bluuebunny/crossref_metadata_2025 huggingface dataset:
Apotransferrin induces cAMP/CREB pathway and cell cycle exit in immature oligodendroglial cells
Authors: Garcia C. , Paez P. , Davio C. , Soto E.F. , Pasquini J.M.
Published: August 2004

We have demonstrated previously that a single intracranial injection of apotransferrin (aTf) in neonatal rats increases myelination and accelerates differentiation of oligodendroglial cells (OLGc). In addition, we have shown through in vitro experiments that OLGc isolated from 4‐day‐old rats (OLGc‐4) treated with aTf were more differentiated than were controls although aTf had no effect upon OLGc isolated from 10‐day‐old animals (OLGc‐10). In the present work, we analyzed the role of second messengers in the effect of aTf upon the maturation of OLGc at different stages of development. We isolated OLGc‐4 and OLGc‐10 from rat brain using a Percoll density gradient and briefly treated the cells with a pulse of aTf or kept them in culture during 2 days in the presence or absence of aTf. In OLGc‐4, after a short pulse of aTf, there was an increase in the levels of cyclic AMP (cAMP), in the phosphorylation of cAMP response element‐binding protein (CREB) and in the DNA‐binding capacity of cAMP‐responsive transcription factors. Treatment of OLGc‐4 with aTf diminished bromodeoxyuridine (BrdU) incorporation and changed levels of p27 and cyclin D1. This glycoprotein seemed to act on OLGc through the cAMP pathway only at early stages of development and on a certain sensitive cell population, accelerating their differentiation, probably as a consequence of premature withdrawal from the cell cycle. © 2004 Wiley‐Liss, Inc.
Environmental change and cultural response between 8000 and 4000 cal. yr BP in the western Loess Plateau, northwest China
Authors: An ChengBang , Feng Zhaodong , Tang Lingyu
Published: August 2004

Two ancient swamps in the western Loess Plateau, northwest China record the climate history between 8000 and 4000 cal. yr BP. Grain size, CaCO3, organic matter, mollusc fauna and pollen assemblages show that climate was wet between 8300 and 7400 cal. yr BP, distinctly humid and warm between 7400 and 6700 cal. yr BP, semi‐humid from 6700 to 6300 cal. yr BP, and semi‐arid between 6300 and 4000 cal. yr BP. The temporal and spatial distribution of archaeological sites shows that the prosperity of the neolithic cultures in the western part of the Chinese Loess Plateau did not appear until the climate changed to semi‐arid, implying that the semi‐arid climate was more favourable than wet and humid climate to neolithic peoples, whose subsistence was based on cereals adapted to arid environments. Copyright © 2004 John Wiley & Sons, Ltd.
The Upper Pleistocene to Holocene sediments on the Mediterranean island of Lampedusa (Italy)
Authors: Giraudi C.
Published: August 2004

The island of Lampedusa lies on the northern edge of the African continental shelf, but during some Quaternary marine lowstands it was joined to the African continent. The study and dating of the aeolian, alluvial, detrital sediments, calcareous crusts and speleothems have established that the climatic–environmental variations recorded on the island can be related chronologically to those known for northern Libya, Tunisia and the Italian peninsula. During the Last Glacial Maximum, phases of Saharan dust accumulation on Lampedusa occurred, and were coeval with dust accumulation in crater lakes and on high mountains in central‐southern Italy, and with phases of glacial advance in the Apennines and in the Alps. During the late Holocene, accumulation of Saharan dust on Lampedusa occurred but there was little accumulation of dust on the northern side of the Mediterranean Sea. With the new data from Lampedusa, it is possible to envisage two different scenarios of atmospheric circulation relating to the Last Glacial Maximum and to the late Holocene. During the Last Glacial Maximum, southerly atmospheric circulation brought rainfall to the southern slopes of the Alps and to the Apennines. During the late Holocene, a prevalent westerly atmospheric circulation became established in the northern Mediterranean. Copyright © 2004 John Wiley & Sons, Ltd.
Elm bark beetle in Holocene peat deposits and the northwest European elm decline
Authors: Clark Sarah H. E. , Edwards Kevin J.
Published: August 2004

The elm decline of 5000 14C yr ago has been the most widely discussed phenomenon in post‐glacial vegetation history. This pan‐European reduction of elm populations, echoed in the decimation of elmwoods in Europe during the twentieth century, has attracted a series of interrelated hypotheses involving climate change, human activity, disease and soil deterioration. The elm bark beetle (Scolytus scolytus L.) is an essential component of disease explanations. We present evidence for the presence of the beetle over a prolonged period (ca. 7950–4910 yr BP [8800–5660 cal. yr BP]) from a lowland raised mire deposit in northeast Scotland, with its final appearance at this site, and the first and only appearance in another mire of a single scolytid find, around the time of the elm decline. The subfossil S. scolytus finds are not only the first from Scotland, but they also represent the most comprehensive sequence of finds anywhere. Copyright © 2004 John Wiley & Sons, Ltd.
Depositional and post‐depositional history of warm stage deposits at Knocknacran, Co. Monaghan, Ireland: implications for preservation of Irish last interglacial deposits
Authors: Vaughan A. P. M. , Dowling L. A. , Mitchell F. J. G. , Lauritzen S.‐E. , McCabe A. M. , Coxon P.
Published: August 2004

Organic‐rich deposits, uncovered during overburden removal from mantled gypsum karst at Knocknacran opencast gypsum mine, Co. Monaghan, are the best candidate to date for a last interglacial record in Ireland. The two till and organic‐rich deposits (preserved at different quarry elevations) were emplaced on to a Tertiary dolerite surface during high‐energy flood events and subsequently folded and faulted by movement towards sinkholes in underlying gypsum. Uranium–thorium disequilibrium dating suggests that the organic‐rich deposits in the upper section were hydrologically isolated at ca. 41 ka and those in the lower section at ca. 86 ka. Interpretation of the pollen content, although tentative because of the depositional and post‐depositional history of the material, suggests that the organic material originated in a warm stage possibly warmer than the post‐Eemian interstadials. The unusual setting of preservation may indicate that in situ, last interglacial deposits have generally been removed by erosion in Ireland. Copyright © 2004 John Wiley & Sons, Ltd.
The Pleistocene Cape Kidnappers section in New Zealand: orbitally forced controls on active margin sedimentation?
Authors: Proust Jean‐Noël , Chanier Frank
Published: August 2004

High sedimentation rates in Pleistocene active margin basins can provide a very detailed record of tectonic and climatic controls on sediment preservation. A 500 m thick, Pleistocene rock section exposed in northeastern North Island of New Zealand (Kidnappers Group), provides the opportunity to discuss these controls. The section is composed of conglomerate, sandstones, siltstones and minor shales, interbedded with tephra layers. The sediments were deposited in alluvial to shallow marine environments and preserved in stacks of depositional units decimetres to hundreds of metres thick as a result of base‐level changes through time. The correlation of base‐level changes in the section with the deep sea oxygen isotope stratigraphy shows that the sequences at 10 m and 80 m scales can correlate, respectively, to the 20 and 100 kyr changes in eustatic sea‐level, but that the 80‐m‐thick sequences correlate also to changes in tectonic uplift rates. A major change in the stratigraphical architecture occurs at the Mid‐Pleistocene Transition (MPT) when the 40 kyr ice volume variations shifted to a dominant 100 kyr variation. This change includes an increase in the amplitude of the shifts in depositional environments and an overall simplification of the stacking pattern of the depositional units through the MPT. This study illustrates that active margin basins can record orbitally forced sedimentary cycles and points to a possible leading influence of eustasy on the pattern of sediment preservation in tectonically active areas. Copyright © 2004 John Wiley & Sons, Ltd.
Heparanase expression in human colorectal cancer and its relationship to tumor angiogenesis, hematogenous metastasis, and prognosis
Authors: Sato Tomohiro , Yamaguchi Akio , Goi Takanori , Hirono Yasuo , Takeuchi Kazuo , Katayama Kanji , Matsukawa Shigeru
Published: August 2004

Background

Heparanase is considered to play an important role in tumor invasion and hematogenous metastasis. The aim of this study was to determine the expression of heparanase in colorectal cancer to evaluate its prognostic value.

Methods

We analyzed heparanase mRNA derived from 130 colorectal cancer patients by reverse transcription polymerase chain reaction (PCR), compared its expression with clinicopathologic factors, and performed statistical analysis. To investigate the relationship between heparanase expression and tumor angiogenesis, 81 primary colorectal tumors were immunostained by use of a monoclonal anti‐CD34 antibody.

Results

Thirty three of 130 cancer tissues overexpressed heparanase. There were significant correlations between heparanase expression and serosal invasion, venous invasion, and liver metastasis. Multivariate analyzes revealed that heparanase mRNA overexpression was a significant independent risk factor for hematogenous metastasis in colorectal cancer. Among 104 patients who underwent curative resection, heparanase expression correlated with a high recurrence. The 5‐year survival rate was 84.6% for patients with heparanase negative tumors, and 47.7% for those with heparanase overexpression; these differences between two groups of patients were significant. In multivariate analysis using the Cox regression model, heparanese expression emerged as an independent prognostic indicator. Moreover, the tumor angiogenesis of heparanase‐positive tumors determined with a monoclonal anti‐CD34 antibody was significantly higher than that of heparanase‐negative tumors.

Conclusions

These results indicated that Heparanase expression may be an important role in invasion and hematogenous metastasis, and may be a biologic marker of prognostic significance in colorectal cancer patients. J. Surg. Oncol. 2004;87:174–181. © 2004 Wiley‐Liss, Inc.
Identification of a single nucleotide polymorphism in the MMP‐1 promoter in chondrosarcoma
Authors: Dickey Ian D. , Scully Sean P.
Published: August 2004

Matrix metalloproteinases (MMPs) are a group of at least 26 enzymes that facilitate cellular invasion via the degradation of the extracellular matrix. Specifically, the ability to degrade collagen types III and I is important in tumor invasion and metastasis. Over expression of the MMP‐1 gene has been shown to correlate with poorer outcome in GI tract and gynecological tumors. This level of expression of this gene has been shown to be significantly increased by the presence of a single nucleotide polymorphism in the MMP‐1 promoter sequence as a result of the creation of an ETS binding site. This SNP results from the addition of a single guanine base at −1,607 bp 24. Two chondrosarcoma cell lines and a series of 10 resected chondrosarcoma specimens underwent DNA extraction, purification, polymerase chain reaction, and sequencing. The presence of the single nucleotide polymorphism at −1,607 bp was confirmed within the promoter region for MMP‐1 in human chondrosarcoma. Because all three genotypes were found in the clinical samples, the SNP may indeed provide a mechanistic explanation for a more aggressive biologic behavior locally and distally for a subset of chondrosarcomas. J. Surg. Oncol. 2004;87:130–133. © 2004 Wiley‐Liss, Inc.
Survival of patients with untreated rectal cancer
Authors: Melissa Solum A. , H. Riffenburgh Robert , A.S. Johnstone Peter
Published: August 2004

Background and Objectives

Untreated rectal cancer is uncommon given modern surgical techniques and chemoradiotherapy. However, neglected cancer may still occur in patients with limited access to medical care or who refuse conventional interventions. Outcome data on such patients is scarce, though valuable in educating patients on their prognosis or to compare with present therapeutic options.

Methods

To identify such data, a review was made of archival literature documenting outcomes in patients with untreated rectal cancer. A review of the Index Medicus and its predecessor volumes and an extensive MEDLINE search led to nine articles that contained relevant age at presentation data of patients with rectal cancer. Six articles also included patient survival data for untreated rectal cancer. Actuarial analysis of the data through 5 years post‐diagnosis was completed.

Results

Symptoms most often presented in the fifth and sixth decades. Median survival of the 1326 patients fell within the second year after presentation of symptoms. Five‐year actuarial survival for these patients was 4.4%. When the data published prior to 1925 were analyzed separately from that published post‐1925, two survival patterns emerged. Median survival of pre‐1925 patients fell within the second year after presentation of symptoms (at 21.5 months by curve fitting) and of post‐1925 patients fell within the first year (10.2 months).

Conclusions

Clearly, advances in antibiotics, surgery, chemoradiotherapy, and supportive care have contributed to increased survival for patients with treated rectal cancer. Recognizing the hazards of generalizing too extremely from the data, they reveal that relatively long survival for patients with untreated lesions is possible. J. Surg. Oncol. 2004;87:157–161. © 2004 Wiley‐Liss, Inc.
Comparison of methylation‐specific polymerase chain reaction (MSP) with reverse transcriptase‐polymerase chain reaction (RT‐PCR) in peripheral blood of gastric cancer patients
Authors: Koike Hiroshi , Ichikawa Daisuke , Ikoma Hisashi , Otsuji Eigo , Kitamura Kazuya , Yamagishi Hisakazu
Published: August 2004

Background and Objectives

To achieve a complete cure in gastric cancer, primary and recurrent tumors must be detected at an early stage. This study was designed to compare carcinoembryonic antigen (CEA)‐specific reverse transcriptase‐polymerase chain reaction (RT‐PCR) and methylation‐specific polymerase chain reaction (MSP) for p16, E‐cadherin, and retinoic acid receptor beta (RARβ) genes using blood samples from gastric cancer patients.

Methods

Preoperative blood samples obtained from 41 patients with gastric cancer, including 9 with early‐stage disease, and were subjected to RT‐PCR and MSP assays.

Results

Ten of 41 (24%) patients exhibited a CEA‐specific signal by RT‐PCR. Positive rates were 11, 13, 50, and 50% in stages I, II, III, and IV, respectively. A significant association was found between RT‐PCR results and stage (P< 0.01). The MSP assay detected hypermethylation of p16 in 9 patients (22%), E‐cadherin in 9 patients (22%), and RARβ in 6 patients (15%). Altogether, 18 patients (44%) showed hypermethylation. The positive rates were 37, 50, 40, and 75% in stages I, II, III, and IV, respectively. A significant association was found between aberrant methylation and venous invasion (P< 0.05). Neither the CEA‐specific signal nor hypermethylation was detected in serum from control volunteers.

Conclusions

The detection rate of MSP was higher than that of RT‐PCR in gastric cancer. Both assays can serve as markers that allow selection of those cases requiring more intensive screening and aggressive postoperative treatment. J. Surg. Oncol. 2004;87:182–186. © 2004 Wiley‐Liss, Inc.
Utility of CEA and CA 19‐9 tumor markers in diagnosis and prognostic assessment of mucinous epithelial cancers of the appendix
Authors: Pablo Carmignani C. , Hampton Regina , E. Sugarbaker Christina , Chang David , H. Sugarbaker Paul
Published: August 2004

Background and Objectives

Tumor markers are a clinical tool frequently used in oncology in association with other clinical and radiologic information. For gastrointestinal cancer, carcinoembryonic antigen (CEA) and carbohydrate antigen 19‐9 (CA 19‐9) tumor markers have found selected clinical application. The use of these tumor markers in mucinous epithelial tumors of the appendix has not been previously determined.

Methods

In patients with peritoneal dissemination of a mucinous epithelial malignancy of the appendix, tumor markers CEA and CA 19‐9 were prospectively recorded preoperatively within 1 week prior to definitive treatment. Also, if the appendiceal tumor recurred, the tumor marker was determined. The accuracy of these two tumor markers in the management of this disease was determined for these two specific clinical situations.

Results

CEA was elevated in 56% of 532 patients and CA 19‐9 was elevated in 67.1% of these patients. Although the absolute level of tumor marker did not correlate with prognosis, a normal value indicated an improved survival. CEA was elevated in 35.2% of 110 patients determined to have recurrent disease; CA 19‐9 was elevated in 62.9% and at least one of the tumor markers was elevated in 68.2% of patients. An elevated CEA tumor marker at the time of recurrence indicated a reduced prognosis.

Conclusions

Both CEA and CA 19‐9 tumor markers were elevated in a majority of these patients and should be a valuable diagnostic tool previously underutilized in this group of patients. These tumor markers were also of benefit in the assessment of prognosis in that a normal level indicated an improved prognosis. At the time of a reoperative procedure, CEA and CA 19‐9 tumor markers gave information regarding the progression of disease. These tumor markers have practical value in the management of epithelial appendiceal malignancy with peritoneal dissemination. J. Surg. Oncol. 2004;87:162–166. © 2004 Wiley‐Liss, Inc.
Risk factors for peritoneal dissemination of colorectal cancer
Authors: Yang Shung‐Haur , Lin Jen‐Kou , Lai Chiung‐Ru , Chen Chien‐Chih , Li A. Fen‐Yau , Liang Wen‐Yih , Jiang Jeng‐Kae
Published: August 2004

Background and Objectives

The aim of this study was to clarify the risk factors associated with positive peritoneal dissemination (PPD) of colorectal cancer (CRC).

Methods

From June 2000 to September 2002, 143 CRC patients who underwent elective curative (79.0%) or non‐curative (21.0%) open laparotomy were prospectively studied. Clinical evaluations including classical factors, colonoscopic evaluation, intraoperative evaluation, and pathological features were recorded. PPD was diagnosed when macro‐ (MAPD) or microscopic peritoneal dissemination (MIPD) was evident. Positive peritoneal cytology from initially existing ascites or washing lavage indicated MIPD. Various factors were analyzed with univariate (Chi‐square test) and then multivariate analyses (logistic regression test) to search for the risk factors of PPD.

Results

Overall, MIPD, MAPD, and PPD were found in 2.8%, 6.3%, and 9.1%, respectively. Univariate analysis identified age ( ≤59 years), CA19‐9 (≥ 34.6 U/ml), poor differentiation, circumferential involvement (≥ 3 quadrants), ascites volume (>80 ml), pN+, and pT4 as risk factors of PPD. PPD did not occur in patients with well‐differentiated tumors, less circumferential involvement (< 2 quadrants), or no lymph node metastasis. After multivariate analysis, CA19‐9 (Odds ratio (95% CI), 8.6 (1.7–43.1)), pT4 (9.0 (1.3–61.0)), and age (5.26 (1.1–25.0)) remained significant risk factors.

Conclusion

CA19‐9 (≥ 34.6 U/ml), pT4, and age ( ≤59 years) were significant risk factors of PPD. J. Surg. Oncol. 2004;87:167–173. © 2004 Wiley‐Liss, Inc.
FAP with concurrent duodenal adenomatous polyposis and carcinoid tumor
Authors: Camp E. Ramsay , Hochwald Steven N. , Liu Chen
Published: August 2004

We report a patient with familial adenomatous polyposis (FAP) who developed duodenal adenomatosis with high‐grade dysplasia and a periampullary carcinoid tumor several years after total colectomy. Only two prior case reports exist revealing carcinoid tumors in association with FAP. No genetic basis exists explaining the link between FAP and carcinoid tumors. However, the presence of two rare entities in the same patient might suggest an association and further research may be indicated. J. Surg. Oncol. 2004;87:187–190. © 2004 Wiley‐Liss, Inc.
Spatio-temporal inhomogeneities of laser induced plasma on surface solutions
Authors: Ben Ahmed J , Ben Lakhdar Z , Taïeb G
Published: August 2004

A transient plasma created by focusing a nanosecond
laser pulse on the surface of ionic solutions of Ca++ and
Mg++ is studied spectroscopically. This kind of plasma has a
properties which vary significantly with time and over its
extended volume. The emissions of ionic and atomic line of calcium
and magnesium are analyzed to get information on the electronic
temperature, the electronic density and on the kinetics of the
population of low atomic and ionic states: 4P1 of CaI,
5S1/2 of CaII, 3P1 of MgII and 3P1/2 of MgII. The
temperature is maximal at the plasma center and it drops at the
edges. The study of the term T(r ≠ 0)/T(r = 0) as a
function of time, where r is the radial position, shows a
continue decreasing with time, which implies that the
inhomogeneity of the temperature develops with time. On the
another side, the electronic density deceases exponentially with
time and does not vary significantly with space. These
measurements allow us to follow the kinetics of the transformation
of calcium (magnesium) from Ca++Mg++ to
Ca+(Mg+) to give at the end Ca (Mg) and to understand
the behavior of self-absorption phenomena which is observed in the
resonance line of CaII at t ≈ 2000 ns to increase with
time. The experimental results are simulated by a kinetics model
of LTE laser induced plasma in its late relaxation period.
Early dental caries detection by fluorescence spectroscopy
Authors: Bakhmutov D , Gonchukov S , Kharchenko O , Nikiforova O , Vdovin Yu
Published: August 2004

In view of its potential for caries diagnostics,
fluorescence spectroscopy in optical range has been the object of
research for the last years. In the frames of this work the
comparative investigations in this direction were accomplished
with the help of fibre optics spectrometer and lasers at the
wavelengths of 473 nm, 532 nm, and 633 nm. Together with
spectroscopic investigations, the element analysis of enamel (of
sound teeth and teeth with caries lesions) was fulfilled with the
help of laser mass-spectrometer.
The effect of indocyanine green pretreatment on the parameters of transscleral diode laser thermotherapy‐induced threshold coagulation of the ciliary body
Authors: Kuo Po‐Cheng , Peyman Gholam A. , Men Gamze , Bezerra Yanno , Torres Franco
Published: August 2004

Background and Objective

To study the effect of indocyanine green (ICG) pretreatment on threshold parameters of transscleral diode laser thermotherapy‐induced threshold coagulation of the ciliary body. The procedure was termed ‘cyclothermotherapy’ based on the long duration (15–60 seconds) of diode laser application.

Study Design/Materials and Methods

The right eyes of nine young adult New Zealand white rabbits underwent transscleral cyclothermotherapy (TCT, Group 1), TCT following ICG pretreatment (Group 2), and external manipulation of the ciliary body alone (Group 3). Rabbits were sacrificed after 24 hours; specimens were evaluated with gross examination and light microscopy.

Results

Thresholds were 30 J/cm2 (TCT) and 4.5 J/cm2 (TCT with ICG). Widespread structural damage was seen in the ciliary processes and the ciliary body in Groups 1 and 2. In Group 3, external manipulation of the ciliary body caused hemorrhage and structural damage confined to the ciliary processes.

Conclusion

ICG pretreatment reduced the energy necessary to cause a threshold lesion with TCT in nonpigmented rabbits. Lasers Surg. Med. 35:157–162, 2004. © 2004 Wiley‐Liss, Inc.
Pulpal safety of 9.6 μm TEA CO2 laser used for caries prevention
Authors: Goodis Harold E. , Fried Daniel , Gansky Stuart , Rechmann Peter , Featherstone John D.B.
Published: August 2004

Background and Objectives

Lasers are used for several procedures involving hard and soft tissues of the oral cavity. A potential future application is the use of the CO2 laser to alter the surface structure of tooth enamel to render it more resistant to caries. A new 9.6 μm wavelength transverse excited atmospheric pressure (TEA) CO2 laser (Argus Photonics, Jupiter, FL) has been investigated as a device that can be used for this purpose without harming the dental pulp.

Study Design/Materials and Methods

Erupted caries‐ and restoration‐free third molars (n = 24 participants; 74 teeth) were used in the study. Teeth were irradiated at an incident fluence of 1.5 J/cm2, a repetition rate of 10 Hz and a spot size 1 mm in diameter. At the low and high settings, 200–400 pulses at 5–8 microseconds pulse duration were delivered at 12 mJ per pulse for a total energy of 2.4 or 4.8 J delivered for 20 or 40 seconds, respectively. Other teeth were subjected to a sham dental procedure (positive control) or no procedure (negative control). Prior to testing, radiographs were taken of all teeth, and they were assessed pulpally using heat, cold, and electricity to determine vitality. The teeth were removed either immediately or at 1 week or 1 month after testing.

Results

Teeth were bioprepared and examined histologically for signs of inflammation. Only one tooth developed symptoms of sensitivity to cold for 10 days following exposure to the high power level. The sensitivity was of fleeting duration and was judged to be reversible pulpitis. All teeth tested responded normally at pre‐testing and pre‐extraction time periods. Histological examination of all teeth disclosed no indication of an inflammatory response in the pulp tissue at any time point. All sections appeared normal with no changes seen in the normal pulpal morphology.

Conclusions

We conclude that the 9.6 μm wavelength laser causes no permanent/serious pulpal damage at the energy levels used and can be used safely for caries prevention treatments in humans. Lasers Surg. Med. 35:104–110, 2004. © 2004 Wiley‐Liss, Inc.
Lasers in pediatric airway surgery: Current and future clinical applications
Authors: Karamzadeh Amir M. , Wong Brian J.F. , Crumley Roger L. , Ahuja Gurpreet
Published: August 2004

Background and Objectives

The smaller anatomy and limited access to instrumentation pose a challenge to the pediatric airway surgeon. The enhanced precision and ability to photocoagulate tissue while operating with the laser enhances the surgeon's ability to successfully treat unique pediatric conditions.

Study Design/Materials and Methods

A comprehensive literature review was performed using the Medline (1995–2004) database.

Results

Due to its shallow tissue penetration and thermal effect, the carbon dioxide (CO2) laser is generally considered the laser of choice for pediatric airway applications. The potential for increased scarring and damage to underlying tissue caused by the greater penetration depth and thermal effect of the Nd:YAG and potassium‐titanyl‐phosphate (KTP) lasers preclude their widespread use in this population.

Conclusions

In this review, we will discuss the clinical applications of lasers in pediatric airway surgery, the current state of the art, where the current technology is deficient, and the potential applications of novel laser systems. Lasers Surg. Med. 35:128–134, 2004. © 2004 Wiley‐Liss, Inc.
Clinical application of Nd:YAG laser for the treatment of small hepatocellular carcinoma with new shaped laser probe
Authors: Ishikawa Tomohisa , Zeniya Mikio , Fujise Kiyotaka , Hokari Astushi , Toda Gotaro
Published: August 2004

Background and Objectives

Surgical resection of hepatocellular carcinoma (HCC) is not always regarded as the first choice of treatment, because most HCCs develop in cirrhotic liver. It becomes adaptation of minimally invasive treatments for HCC. In animal experiments, we previously reported that our newly developed neodymium:yttrium aluminum garnet (Nd:YAG) laser system could ablate liver tissue in short periods.

Study Design/Patients and Methods

Six HCC cases (mean diameter; 16.3 ± 3.50 mm) were enrolled. The Nd:YAG laser generator with a wavelength of 1,064 nm at 10 W of power emitted the laser in a forward fashion and in all patients the laser beam safely irradiated the target lesion.

Results

There was no recurrence of HCC in the laser‐ablated area in six patients for duration of 21.8± 4.35 months. A local recurrence was found in only one patient.

Conclusions

This study showed the clinical usefulness of laser ablation in the treatment of HCC. Lasers Surg. Med. 35:135–139, 2004. © 2004 Wiley‐Liss, Inc.
Feasibility study of normal and septic tracheal imaging using optical coherence tomography
Authors: Jung Woonggyu , Zhang Jun , Mina‐Araghi Reza , Hanna Nevine , Brenner Matthew , Nelson J. Stuart , Chen Zhongping
Published: August 2004

Background and Objectives

Optical coherence tomography (OCT) is an imaging technology that may be adapted for use with flexible fiberoptic bronchoscopy, potentially allowing it to play an important role in pulmonary diagnostics. The goal of this study was to evaluate the feasibility of OCT to image tracheal pathology.

Study Design/Materials and Methods

Tracheas were harvested from normal and septic New Zealand White rabbits and imaged using OCT. Two delivery devices were employed. One was a moving stage with an objective lens and collimator, the other a linear scanning flexible fiberoptic catheter using a GRIN lens and prism for endoscopic OCT. After OCT images were obtained from normal and septic tracheas, the excised tissues were prepared for standard histologic examination. Areas imaged by OCT were compared with corresponding histology slides.

Results

OCT images demonstrated in detail tracheal sub‐surface structures such as the epithelium, lamina propria, submucosa, and cartilage. The appearance of structures imaged by OCT corresponded very well with histologic pictures obtained by light microscopy. The OCT images from septic tracheas showed marked swelling of the mucosal and submucosal layers. Such pathology was equally imaged by either the moving stage or fiberoptic catheter for endoscopic OCT.

Conclusions

OCT images of the trachea can distinguish many sub‐surface structural features usually requiring biopsy and light microscopy for visualization. Marked differences between normal and septic trachea were apparent in OCT images. In the future, OCT may be a valuable tool for evaluating tracheal pathology in situ with high image resolution. Lasers Surg. Med. 35:121–127, 2004. © 2004 Wiley‐Liss, Inc.
Effects of low‐intensity laser therapy on the orthodontic movement velocity of human teeth: A preliminary study
Authors: Cruz Delma R. , Kohara Eduardo K. , Ribeiro Martha S. , Wetter Niklaus U.
Published: August 2004

Background and Objectives

Low‐intensity laser therapy (LILT) has been studied in many fields of dentistry, but to our knowledge, this is the first time that its effects on orthodontic movement velocity in humans are investigated.

Study Design/Patients and Methods

Eleven patients were recruited for this 2‐month study. One half of the upper arcade was considered control group (CG) and received mechanical activation of the canine teeth every 30 days. The opposite half received the same mechanical activation and was also irradiated with a diode laser emitting light at 780 nm, during 10 seconds at 20 mW, 5 J/cm2, on 4 days of each month. Data of the biometrical progress of both groups were statistically compared.

Results

All patients showed significant higher acceleration of the retraction of canines on the side treated with LILT when compared to the control.

Conclusions

Our findings suggest that LILT does accelerate human teeth movement and could therefore considerably shorten the whole treatment duration. Lasers Surg. Med. 35:117–120, 2004. © 2004 Wiley‐Liss, Inc.
Repetitive Er:YAG laser irradiation of human skin: A histological evaluation
Authors: Drnovšek‐Olup Brigita , Beltram Matej , Pižem Jože
Published: August 2004

Background and Objective

Deep coagulation of skin collagen by Er:YAG laser repetitive pulses has been predicted by previous theoretical models and later demonstrated on animal skin. The goal of this study was to determine the effect of repetitive Er:YAG laser pulses on human skin and its response to this treatment.

Study Design/Materials and Methods

Lid skin of six female volunteers with blepharochalasis has been treated with laser at day 0, 7, and 21 before elective surgery—blepharoplasty. The treated skin was excised as part of the procedure and prepared for further histological examination. We used a 2,940 nm Er:YAG laser (Fidelis M320A by Fotona) with ‘smooth’ mode parameters: fluence from 0.50 to 2.00 J/cm2; six pulses per packet; 550 μsecond/pulse, 250 millisecond/packet; single pass, no overlapping; spot size 5 mm; repetition rate 20 Hz.

Results

We observed deep collagen denaturation at laser fluences of 1.25 J/cm2 and over; epidermal damage was proportional to fluence with total coagulation of the epidermal layer at fluences of 1.75 J/cm2 and over. At day 7 after laser treatment we observed a complete regeneration of the epidermal layer and a regeneration zone within the dermis with prominent infiltration of CD68+ monocytes/macrophages. At day 21 after laser treatment we observed collagen remodeling and (myo‐)fibroblast proliferation at tissue depths of up to 240 μm.

Conclusions

Repetitive Er:YAG laser irradiation is effective in deep denaturation and remodeling of human skin collagen in vivo, with less epidermal damage compared to standard Er:YAG laser skin resurfacing. Lasers Surg. Med. 35:146–151, 2004. © 2004 Wiley‐Liss, Inc.
Albumin–genipin solder for laser tissue repair
Authors: Lauto A. , Foster L.J.R. , Ferris L. , Avolio A. , Zwaneveld N. , Poole‐Warren L.A.
Published: August 2004

Background

Laser tissue soldering (LTS) is an alternative technique to suturing for tissue repair that avoids foreign body reaction and provides immediate sealing of the wound. One of the major drawbacks of LTS, however, is the weak tensile strength of the solder welds when compared to sutures. In this study, a crosslinking agent of low cytotoxicity was investigated for its ability to enhance the bond strength of albumin solders with sheep intestine.

Study Design/Materials and Methods

Solder strips were welded onto rectangular sections of sheep small intestine using a diode laser. The laser delivered in continuous mode a power of 170 ± 10 mW at λ = 808 nm, through a multimode optical fiber (core size = 200 μm) to achieve a dose of 10.8 ± 0.5 J/mg. The solder thickness and surface area were kept constant throughout the experiment (thickness = 0.15 ± 0.01 mm, area = 12 ± 1.2 mm2). The solder was composed of 62% bovine serum albumin (BSA), 0.38% genipin, 0.25% indocyanin green dye (IG), and water. Tissue welding was also performed with a BSA solder without genipin, as a control group. The repaired tissue was tested for tensile strength by a calibrated tensiometer. Murine fibroblasts were also cultured in extracted media from heat‐denatured genipin solder to assess cell growth inhibition in a 48 hours period.

Results

The tensile strength of the genipin solder was doubled that of the BSA solder (0.21 ± 0.04 N and 0.11 ± 0.04 N, respectively; P = 10−15 unpaired t‐test, N = 30). Media extracted from crosslinked genipin solder showed negligible toxicity to fibroblast cells under the culture conditions examined here.

Conclusion

Addition of a chemical crosslinking agent, such as genipin, significantly increased the tensile strength of adhesive‐tissue bonds. A proposed mechanism for this enhanced bond strength is the synergistic action of mechanical adhesion with chemical crosslinking by genipin. Lasers Surg. Med. 35:140–145, 2004. © 2004 Wiley‐Liss, Inc.
How social influence affects consumption trends in emerging markets: An empirical investigation of the consumption convergence hypothesis
Authors: Dholakia Utpal M. , Talukdar Debabrata
Published: August 2004

The authors empirically test the veracity of the consumption convergence hypothesis for emerging markets (EMs): the hypothesis that through social influences on individual consumers resulting from global integration, and exposure to the United States (U.S.), consumption levels in EMs converge toward U.S. consumption levels. Drawing upon psychological theories of social influence, and using national per capita consumption data from 22 major EMs and the U.S., the authors find strong empirical support for consumption convergence for both, the aggregate consumption level of EMs, as well as for soft‐drink consumption therein. After controlling for income and price levels, the results show that global integration and exposure to the U.S. each increase the EM's consumption convergence. The authors also find that degree of global integration interacts with specific exposure to the U.S., accelerating consumption convergence of EMs. Theoretical and practical implications of the results are considered, and future research opportunities are discussed. © 2004 Wiley Periodicals, Inc.
Role of tumor cell immune escape mechanisms in cytomegalovirus‐mediated oncomodulation
Authors: Cinatl Jindrich , Scholz Martin , Doerr Hans Wilhelm
Published: August 2004

It has been known for a long time that cytomegalovirus (CMV) has evolved mechanisms that allow the escape from the host immune surveillance. In the past, many efforts have been done to elucidate the molecular mechanisms underlying this virus‐mediated immune escape and thus virus persistence. However, it is unknown, whether CMV may also impair immune responses directed against tumor cells. This might have severe consequences on tumor progression and may explain the growing evidence for CMV‐mediated oncomodulation. This review summarizes recent work on CMV‐mediated immune escape mechanisms of tumor cells and oncomodulation and proposes novel aspects that may be important for understanding the CMV‐associated tumor progression. © 2004 Wiley Periodicals, Inc.
31P MAS‐NMR of human erythrocytes: Independence of cell volume from angular velocity
Authors: Kuchel P.W. , Bubb W.A. , Ramadan S. , Chapman B.E. , Philp D.J. , Coen M. , Gready J.E. , Harvey P.J. , McLean A.J. , Hook J.
Published: August 2004

31P magic angle spinning NMR (MAS‐NMR) spectra were obtained from suspensions of human red blood cells (RBCs) that contained the cell‐volume‐sensitive probe molecule, dimethyl methylphosphonate (DMMP). A mathematical representation of the spectral‐peak shape, including the separation and width‐at‐half‐height in the 31P NMR spectra, as a function of rotor speed, enabled us to explore the extent to which a change in cell volume would be reflected in the spectra if it occurred. We concluded that a fractional volume change in excess of 3% would have been detected by our experiments. Thus, the experiments indicated that the mean cell volume did not change by this amount even at the highest spinning rate of 7 kHz. The mean cell volume and intracellular 31P line‐width were independent of the packing density of the cells and of the initial cell volume. The relationship of these conclusions to other non‐NMR studies of pressure effects on cells is noted. Magn Reson Med 52:663–668, 2004. © 2004 Wiley‐Liss, Inc.
Analysis of noise effects on DTI‐based tractography using the brute‐force and multi‐ROI approach
Authors: Huang Hao , Zhang Jiangyang , van Zijl Peter C.M. , Mori Susumu
Published: August 2004

Diffusion tensor tractography based on line propagation is a promising and widely used technique, but it is known to be sensitive to noise and the size and location of the seed regions of interest (ROIs). The effects of these parameters on the tractography results were analyzed quantitatively using high‐resolution diffusion tensor imaging (DTI) with a high signal‐to‐noise ratio (SNR) on a fixed mouse brain. The anterior commissure (AC), as judged from a T2‐weighted image, was used as an anatomical reference within which the tracts could be located. Monte Carlo simulation was performed by adding Gaussian noise to the time domain data and repeating the tractography. Deviations of the tracking results were measured as a function of SNR. Such noise effects were evaluated for a simple one‐ROI approach and a combined two‐ROI and brute‐force (BF) approach. The influence of ROI size and location for the two‐ROI + BF approach was also analyzed. The results confirmed the hypothesis that one can increase the validity of DTI‐based tractography by adopting the BF and multi‐ROI approach, with respect to the simple one‐ROI approach. Magn Reson Med 52:559–565, 2004. © 2004 Wiley‐Liss, Inc.
Comparison between 2D and 3D gradient‐echo sequences for MRI of human lung ventilation with hyperpolarized 3He
Authors: Wild Jim M. , Woodhouse Neil , Paley Martyn N.J. , Fichele Stan , Said Zead , Kasuboski Larry , van Beek Edwin J.R.
Published: August 2004

Images of hyperpolarized 3He were acquired during breath‐hold in four healthy volunteers with the use of an optimized 3D gradient‐echo sequence. The images were compared with existing 2D gradient‐echo methods. The average SNR from a 13‐mm‐thick slice in the peripheral lung was 1.4 times greater with 3D. In the airways the average SNR was 1.7 times greater with 3D. The higher SNR of 3D was particularly evident when regions of unimpeded gas diffusion, such as the major airways, were imaged with thin slices. This is because diffusion dephasing due to the slice‐encoding gradient is minimized with a 3D sequence. The in vivo experimental findings were substantiated with experiments on phantoms of free gas, which showed more than four times the SNR with 3D compared to 2D. Theoretical simulations of the 2D and 3D k‐space filters were also performed to predict the SNR and spatial resolution observed in the experimental images. Magn Reson Med 52:673–678, 2004. © 2004 Wiley‐Liss, Inc.
Variable‐rate selective excitation for rapid MRI sequences
Authors: Hargreaves Brian A. , Cunningham Charles H. , Nishimura Dwight G. , Conolly Steven M.
Published: August 2004

Balanced steady‐state free precession (SSFP) imaging sequences require short repetition times (TRs) to avoid off‐resonance artifacts. The use of slab‐selective excitations is common, as this can improve imaging speed by limiting the field of view (FOV). However, the necessarily short‐duration excitations have poor slab profiles. This results in unusable slices at the slab edge due to significant flip‐angle variations or aliasing in the slab direction. Variable‐rate selective excitation (VERSE) is a technique by which a time‐varying gradient waveform is combined with a modified RF waveform to provide the same excitation profile with different RF power and duration characteristics. With the use of VERSE, it is possible to design short‐duration pulses with dramatically improved slab profiles. These pulses achieve high flip angles with only minor off‐resonance sensitivity, while meeting SAR limits at 1.5 T. The improved slab profiles will enable more rapid 3D imaging of limited volumes, with more consistent image contrast across the excited slab. Magn Reson Med 52:590–597, 2004. © 2004 Wiley‐Liss, Inc.
Assessing DTI data quality using bootstrap analysis
Authors: Heim S. , Hahn K. , Sämann P.G. , Fahrmeir L. , Auer D.P.
Published: August 2004

Diffusion tensor imaging (DTI) is an established method for characterizing and quantifying ultrastructural brain tissue properties. However, DTI‐derived variables are affected by various sources of signal uncertainty. The goal of this study was to establish an objective quality measure for DTI based on the nonparametric bootstrap methodology. The confidence intervals (CIs) of white matter (WM) fractional anisotropy (FA) and Clinear were determined by bootstrap analysis and submitted to histogram analysis. The effects of artificial noising and edge‐preserving smoothing, as well as enhanced and reduced motion were studied in healthy volunteers. Gender and age effects on data quality as potential confounds in group comparison studies were analyzed. Additional noising showed a detrimental effect on the mean, peak position, and height of the respective CIs at 10% of the original background noise. Inverse changes reflected data improvement induced by edge‐preserving smoothing. Motion‐dependent impairment was also well depicted by bootstrap‐derived parameters. Moreover, there was a significant gender effect, with females displaying less dispersion (attributable to elevated SNR). In conclusion, the bootstrap procedure is a useful tool for assessing DTI data quality. It is sensitive to both noise and motion effects, and may help to exclude confounding effects in group comparisons. Magn Reson Med 52:582–589, 2004. © 2004 Wiley‐Liss, Inc.
Semiquantitative fast flow velocity measurements using catheter coils with a limited sensitivity profile
Authors: Volz Steffen , Zuehlsdorff Sven , Umathum Reiner , Hallscheidt Peter , Fink Christian , Semmler Wolfhard , Bock Michael
Published: August 2004

Flow measurements can be used to quantify blood flow during MR‐guided intravascular interventional procedures. In this study, a fast flow measurement technique is proposed that quantifies flow velocities in the vicinity of a small RF coil attached to an intravascular catheter. Since the small RF coil receives signal from only a limited volume around the catheter, a spatially nonselective signal reception is employed. To enhance signal from flowing blood, and suppress unwanted signal contributions from static material, a slice‐selective RF excitation is used. At a velocity sensitivity of 150 cm/s, a temporal resolution of 2 × TR = 10.2 ms can be achieved. The flow measurement is combined with an automatic slice positioning to facilitate measurements during interventional procedures. The influence of the catheter position in the blood vessel on the velocity measurement was analyzed in simulations. For blood vessels with laminar flow, the simulation showed a systematic deviation between catheter measurement and true flow between −15% and 80%. In four animal experiments, the catheter velocity measurement was compared with results from a conventional ECG‐triggered 2D phase‐contrast (PC) technique. The shapes of the velocity time curves in the abdominal aorta were nearly identical to the conventional measurements. A relative scaling factor of 0.69–1.19 was found between the catheter velocity measurement and the reference measurement, which could be partly explained by the simulation results. Magn Reson Med 52:575–581, 2004. © 2004 Wiley‐Liss, Inc.
Shim design using a linear programming algorithm
Authors: Ungersma Sharon E. , Xu Hao , Chronik Blaine A. , Scott Greig C. , Macovski Al , Conolly Steven M.
Published: August 2004

The advent of open magnetic resonance imaging (MRI) scanners and dedicated MRI scanners tailored to specific body parts has led to an increasing number of noncylindrical MRI scanner geometries, for which noncylindrical gradients and shims are needed. These new scanner geometries are driving the need for fast, flexible shim design methods that can design shim coils for any geometry. A linear programming (LP) algorithm was developed to design minimum‐power resistive shim coils on an arbitrary surface. These coils can be designed to produce any order shim field over an arbitrarily shaped target region, which can be placed anywhere within the coil. The resulting designs are relatively sparse and can be readily constructed. This algorithm was used to design and construct a seven‐coil cylindrical shim set for a knee imaging magnet with a cylindrical homogeneous region. The algorithm was then used to design shim coils for a biradial head imager with an asymmetrically located spherical target region for brain imaging. Magn Reson Med 52:619–627, 2004. © 2004 Wiley‐Liss, Inc.