bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐linear analysis of a collapsed reinforced concrete chimney
Authors: Huang Wei , Gould Phillip L. , Martinez Raul , Johnson Gayle S. 
Published: March 2004

AbstractDuring the Ismit (Kocaeli) earthquake of 17 08 1999, a 115 high reinforced concrete chimney or heater stack, located at the Tüpras Refinery, collapsed. The falling debris cut 63 pipes, which contributed to interrupted production for more than 14 months. This stack was designed and constructed according to international standards and is representative of similar structures at refineries throughout the world, including those in earthquake‐prone regions. It was distinguished from similar stacks at the site by a much larger rectangular opening for the flue duct, circumscribing a horizontal arc of about 50°. The opening was located about 1/3 of the height above the base and appeared to be the region of initiation of the collapse.The investigation is focused on the dynamic response of the stack due to an earthquake motion recorded at a nearby site. In this paper the results of a response spectrum analysis of the Tüpras stack and a generic U.S. stack are summarized. Then, an on‐linear static analysis of the collapsed stack is presented using a demand–collapse comparison. The demand is represented by an acceleration–displacement response spectrum based on the recorded motion as well as some smoothed adaptations typical of design spectra, while the capacities are calculated from pushover curves using a non‐linear reinforced concrete finite element analysis.Results are presented that show the effects of the hole and the orientation of the motion with respect to the hole. Also higher‐mode contributions to the pushover pattern are considered. The results confirm that the stack could readily fail under the considered earthquake and are also consistent with the debris pattern. Copyright © 2003 JohnWiley & Sons, Ltd.
Cumulative damage‐based inelastic cyclic demand spectrum
Authors: Kunnath S. K. , Chai Y. H. 
Published: March 2004

AbstractThe estimation of cyclic deformation demand resulting from earthquake loads is crucial to the core objective of performance‐based design if the damage and residual capacity of the system following a seismic event needs to be evaluated. A simplified procedure to develop the cyclic demand spectrum for use in preliminary seismic evaluation and design is proposed in this paper. The methodology is based on estimating the number of equivalent cycles at a specified ductility. The cyclic demand spectrum is then determined using well‐established relationships between seismic input energy and dissipated hysteretic energy. An interesting feature of the proposed procedure is the incorporation of a design spectrum into the proposed procedure. It is demonstrated that the force–deformation characteristics of the system, the ductility‐based force‐reduction factor Rμ, and the ground motion characteristics play a significant role in the cyclic demand imposed on a structure during severe earthquakes. Current design philosophy which is primarily based on peak response amplitude considers cyclic degradation only in an implicit manner through detailing requirements based on observed experimental testing. Findings from this study indicate that cumulative effects are important for certain structures, classified in this study by the initial fundamental period, and should be incorporated into the design process. Copyright © 2003 John Wiley & Sons, Ltd.
Potassium attenuates zinc‐induced death of cultured cortical astrocytes
Authors: Sheline Christian T. , Takata Toshihiro , Ying Howard , Canzoniero Lorella M.t. , Yang Aizhen , Yu Shan Ping , Choi Dennis W. 
Published: March 2004

AbstractTransient global ischemia induces CA1 hippocampal neuronal death without astrocyte death, perhaps mediated in part by the toxic translocation of zinc from presynaptic terminals to postsynaptic neurons. We tested the hypothesis that cellular depolarization, which occurs in the ischemic brain due to increased extracellular potassium and energy failure, might contribute to astrocyte resistance to zinc‐induced death. We previously reported that neurons in mixed cortical neuronal‐astrocyte cultures were more vulnerable to a 5–15‐min exposure to Zn2+ than astrocytes in the same cultures. In the present report, we show that (1) neurons in isolation or in conjunction with astrocytes were 2–3‐fold more sensitive to a 15‐min nondepolarizing Zn2+ exposure than are glia; (2) KCl‐induced depolarization attenuated glial vulnerability to zinc toxicity but potentiated neuronal vulnerability to zinc toxicity; (3) Zn2+‐induced glial death was attenuated by T‐type Ca2+ channel blockade, as well as compounds that increase NAD+ levels; and (4) both astrocytic 65Zn2+ accumulation and the increase in astrocytic [Zn2+]i induced by Zn2+ exposure were also attenuated by depolarization or T‐type Ca2+ channel blockers. Zn2+‐induced cell death in astrocytes was at least in part apoptotic, as caspase‐3 was activated, and the caspase inhibitor Z‐Val‐Ala‐Asp‐fluoromethylketone partially attenuated Zn2+‐induced death. The levels of peak [Zn2+]i achieved in astrocytes during this toxic nondepolarizing Zn2+ exposure (250 nM) were substantially greater than those achieved in neurons (40 nM). In glia, exposure to 400 μM Zn2+ induced a 13‐mV depolarization, which can activate T‐type Ca2+ channels. This Zn2+‐induced astrocyte death, like neuronal death, was attenuated by the addition of pyruvate or niacinamide to the exposure medium. © 2004 Wiley‐Liss, Inc.
Increased expression of two phospholipase D isoforms during experimentally induced hippocampal mossy fiber outgrowth
Authors: Zhang Yan , Huang Ping , Du Guangwei , Kanaho Yasunori , Frohman Michael A. , Tsirka Stella E. 
Published: March 2004

AbstractMammalian phospholipase D (PLD), a multifunctional signaling enzyme, has been reported to facilitate neurite outgrowth in cultured neurons. However, two mammalian isoforms have been found, PLD1 and PLD2, and it has not been determined which isoform is involved, or whether this in vitro phenomenon is relevant to neurite extension in vivo. Using confocal microscopy, we demonstrate that the PLDs are expressed by different cell types in the mouse brain: PLD1 by neurons, and PLD2 by astrocytes. Moreover, using a model of experimentally induced hippocampal mossy fiber sprouting, both isoforms were observed to increase dramatically in expression level along tracts of mossy fiber spouting, supporting the proposal that PLD plays a role in this process. Given that the two isoforms undertake unique molecular functions in cultured cells, our findings suggest that in vivo PLD1 and PLD2 may modulate neuronal plasticity via different pathways and cell types. © 2004 Wiley‐Liss, Inc.
Expression profiling in tuberous sclerosis complex (TSC) knockout mouse astrocytes to characterize human TSC brain pathology
Authors: Ess Kevin C. , Uhlmann Erik J. , Li Wen , Li Hongzhen , Declue Jeffrey E. , Crino Peter B. , Gutmann David H. 
Published: March 2004

AbstractIndividuals with tuberous sclerosis complex (TSC) exhibit a variety of neurologic abnormalities, including mental retardation, epilepsy, and autism. Examination of human TSC brains demonstrate dysplastic astrocytes and neurons, areas of abnormal neuronal migration (tubers), and hamartomatous growths, termed subependymal nodules, which can progress to subependymal giant cell astrocytomas (SEGA). Previous studies have suggested that these neuropathologic features may result from abnormal neuroglial cell differentiation. In an effort to provide support for this hypothesis and to identify specific markers of aberrant neuroglial cell differentiation in TSC, we employed gene expression profiling on Tsc1 conditional knockout (Tsc1GFAPCKO) mouse astrocytes. We identified several transcripts implicated in central nervous system development that are differentially expressed in Tsc1−/− astrocytes compared to wild‐type astrocytes. We validated the differential expression of select transcripts on the protein level both in primary cultures of Tsc1−/− astrocytes and in Tsc1GFAPCKO mouse brains. Moreover, we show that these markers are also differentially expressed within cortical tubers, but not in adjacent normal tissue from TSC patient brains. This study provides supportive evidence for a developmental defect in neuroglial cell differentiation relevant to the genesis of TSC nervous system pathology and underscores the utility of mouse modeling for understanding the molecular pathogenesis of human disease. © 2004 Wiley‐Liss, Inc.
Novel metabotropic glutamate receptor negatively coupled to adenylyl cyclase in cultured rat cerebellar astrocytes
Authors: Kanumilli Srinivasan , Toms Nick J. , Roberts Peter J. 
Published: March 2004

AbstractSeveral excitatory amino acid ligands were found potently to inhibit forskolin‐stimulated cAMP accumulation in rat cultured cerebellar astrocytes: L‐cysteine sulfinic acid (L‐CSA) = L‐aspartate > L‐glutamate ≥ the glutamate uptake inhibitor, L‐PDC. This property did not reflect activation of conventional glutamate receptors, since the selective ionotropic glutamate receptor agonists NMDA, AMPA, and kainate, as well as several mGlu receptor agonists [(1S,3R)‐ACPD, (S)‐DHPG, DCG‐IV, L‐AP4, L‐quisqualate, and L‐CCG‐I], were without activity. In addition, the mGlu receptor antagonists, L‐AP3, (S)‐4CPG, Eglu, LY341495, (RS)‐CPPG, and (S)‐MCPG failed to reverse 30 μM glutamate‐mediated inhibitory responses. L‐PDC‐mediated inhibition was abolished by the addition of the enzyme glutamate‐pyruvate transaminase. This finding suggests that the effect of L‐PDC is indirect and that it is mediated through endogenously released L‐glutamate. Interestingly, L‐glutamate‐mediated inhibitory responses were resistant to pertussis toxin, suggesting that Gi/Go type G proteins were not involved. However, inhibition of protein kinase C (PKC, either via the selective PKC inhibitor GF109203X or chronic PMA treatment) augmented glutamate‐mediated inhibitory responses. Although mGlu3 receptors (which are negatively coupled to adenylyl cyclase) are expressed in astrocyte populations, in our study Western blot analysis indicated that this receptor type was not expressed in cerebellar astrocytes. We therefore suggest that cerebellar astrocytes express a novel mGlu receptor, which is negatively coupled to adenylyl cyclase, and possesses an atypical pharmacological profile. © 2003 Wiley‐Liss, Inc.
Induction of glial L‐CCR mRNA expression in spinal cord and brain in experimental autoimmune encephalomyelitis
Authors: Brouwer N. , Zuurman M.W. , Wei T. , Ransohoff R.M. , Boddeke H.W.G.M. , Biber K. 
Published: March 2004

AbstractChemokines and chemokine receptors are important regulators of leukocyte trafficking and immune response. It is well established that chemokines and their receptors are also expressed in the central nervous system (CNS), where their expression has been associated with various neuroinflammatory diseases, such as multiple sclerosis (MS). One of the most important chemokines involved in MS pathology is CCL2 (previously known as MCP‐1). CCL2, released by glial cells, activates the chemokine receptor CCR2, causing the infiltration of blood monocytes in tissues affected by MS. There is evidence, however, that CCL2 also has local effects on CNS cells, including induction or modulation of cytokine release and synthesis of matrix metalloproteinases, that might contribute to CNS pathology. These effects are most likely independent of CCR2, since CCR2 expression in glial cells is rarely observed. We have recently provided evidence for the presence of an alternative CCL2 receptor in glial cells called L‐CCR and have investigated the expression of L‐CCR mRNA in a murine EAE model. It is shown that L‐CCR mRNA is expressed in infiltrating macrophages during EAE, but not in infiltrating T cells. Prominent expression of L‐CCR mRNA was detected in astrocytes and microglia already at early time points throughout the brain and spinal cord supporting the hypothesis that L‐CCR expression in glial cells is related to CNS inflammation. © 2004 Wiley‐Liss, Inc.
Targeted sensory restoration to the upper aerodigestive tract with physiologic implications
Authors: Urken Mark L. 
Published: March 2004

AbstractBackground.Sensory restoration through sensate flaps placed into critical areas of the upper aerodigestive tract is an attractive reconstructive goal to achieve optimal post‐therapy function. The question that has remained unanswered is whether sensory recovery takes place through the newly established neural pathway or through ingrowth of sensory nerves from the periphery of the defect.Methods.Three patients with squamous cell cancer underwent resection and primary reconstruction of the laryngopharynx with a sensate radial forearm flap. The flaps were designed with a smaller, proximal paddle to serve as a monitor. Reneurotization of the flaps was carried out to the superior laryngeal nerve.Results.All three patients were followed for a minimum of 12 months. Each of these patients reported the development of a cough that resulted from stimulation of the external monitor. This phenomenon was easily duplicated by light stimulation of the monitor, which not only produced the cough but was consistently perceived by the patient as arising from inside their throat.Conclusions.This series conclusively demonstrates that sensory feedback can be restored in a targeted fashion through neural anastomoses and that a physiologic response that helps in airway protection can be produced through the use of sensate flaps with a strategically selected recipient nerve. © 2004 Wiley Periodicals, Inc. Head Neck 26: 287–293, 2004
Bilateral vocal fold paresis after endoscopic stapling diverticulotomy for zenker's diverticulum
Authors: Thorne Marc , Harris Philip , Marcus Keith , Teknos Theodoros N. 
Published: March 2004

AbstractBackground.Zenker's diverticulum may be treated with a variety of surgical techniques. Endoscopic methods, specifically endoscopic stapling diverticulotomy, have gained increasing acceptance because of shorter operative times, decreased morbidity, with shorter hospital stays and time to resumption of oral feedings.Methods and Results.We report the occurrence of bilateral vocal fold paresis after endoscopic stapling diverticulotomy for Zenker's diverticulum, previously unreported in the literature. This complication likely resulted from traction on the recurrent laryngeal nerves secondary to unfavorable patient anatomy.Conclusions.Endoscopic stapling diverticulotomy is a safe and effective treatment method for Zenker's diverticulum and remains our procedure of choice for most patients. However, inability to safely expose the diverticulum endoscopically results in a significant abandonment rate for attempted procedures and may result in significant postoperative complications.© 2004 Wiley Periodicals, Inc. Head Neck 26: 294–297, 2004
Surgical management of maxillectomy defects based on the concept of buttress reconstruction
Authors: Yamamoto Yuhei , Kawashima Kunihiro , Sugihara Tsuneki , Nohira Kunihiko , Furuta Yasushi , Fukuda Satoshi 
Published: March 2004

AbstractBackground.Few published large series have described a surgical approach to maxillary skeletal reconstruction on the basis of the extent of maxillectomy.Methods.We have reviewed a 10‐year experience with 38 consecutive maxillary reconstructions with respect to maxillectomy defects, reconstructive procedures, reconstructed buttresses, and functional and aesthetic outcomes.Results.Maxillectomy defects were classified into three categories on the basis of the buttress concept. Buttress reconstruction was most frequently performed in category III maxillary defects (56%), followed by category I (50%) and category II (20%). The vascularized composite autograft included the rectus abdominis myocutaneous free flap combined with costal cartilage, and the latissimus dorsi myocutaneous free flap combined with the V‐shaped scapula is an effective method for reliable reconstruction of both skeletal and soft tissues.Conclusions.A critical assessment for skeletal defects and associated soft tissue defects is essential for an adequate approach to solve complex problems in maxillary reconstruction. On the basis of retrospective analysis of this series, a reconstructive algorithm for surgical management of maxillectomy defects is proposed. © 2004 Wiley Periodicals, Inc. Head Neck 26: 247–256, 2004
Comparing cancer patients who enroll in a smoking cessation program at a comprehensive cancer center with those who decline enrollment
Authors: Schnoll Robert A. , Rothman Randi L. , Lerman Caryn , Miller Suzanne M. , Newman Holly , Movsas Benjamin , Sherman Eric , Ridge John A. , Unger Michael , Langer Corey , Goldberg Melvyn , Scott Walter , Cheng Jonathan 
Published: March 2004

AbstractBackground.Despite the availability of smoking interventions for cancer patients, many eligible patients decline enrollment into such programs. We examined reasons patients provide for declining smoking treatment and compared treatment decliners to enrollees.Methods.Eligible cancer patients (N = 231) were offered smoking cessation treatment. During recruitment, demographic, medical (eg, cancer stage), and smoking‐related behavioral (eg, readiness to quit) data were collected, and decliners stated a reason for refusal. Patients who enrolled in the cessation program (N = 109) were compared with those who declined (N = 122) in terms of recruitment data, and reasons for declining were compiled.Results.Decliners were significantly more likely to: (1) have head and neck cancer (vs lung cancer); (2) exhibit fewer physical symptoms (eg, shortness of breath); (3) report a lower readiness to quit smoking; (4) indicate no intention to quit smoking; and (5) smoke fewer cigarettes. A preference to quit without professional assistance was the most common reason for declining treatment.Conclusions.Our findings highlight important differences between patients who enroll in a smoking cessation program and those who decline and underscore the need for motivational interventions to facilitate enrollment into smoking interventions for cancer patients. © 2004 Wiley Periodicals, Inc. Head Neck 26: 278–286, 2004
Genetically targeted radiotherapy of head and neck squamous cell carcinoma using the sodium‐iodide symporter (NIS)
Authors: Gaut Andrew W. , Niu Gang , Krager Kimberly J. , Graham Michael M. , Trask Douglas K. , Domann Frederick E. 
Published: March 2004

AbstractBackground.Gene therapy that uses delivery of the sodium‐iodide symporter (NIS) gene followed by radioiodide administration has been proposed as a novel form of radiotherapy for nonthyroidal cancers.Methods.In vitro [125I] iodide accumulation and efflux from cells was determined after treatment with an NIS‐expressing adenovirus (Ad‐NIS). A clonogenic survival assay and tumor growth experiment that used athymic mice were used to demonstrate the in vitro and in vivo cytotoxicity of Ad‐NIS treatment and [131I] iodide delivery.Results.Head and neck squamous cell carcinoma (HNSCC) cell lines treated with Ad‐NIS exhibit significant amounts of radioiodide accumulation and retention. In vitro HNSCC cell survival was significantly diminished after NIS gene delivery followed by administration of [131I] iodide. Moreover, NIS gene transfer/[131I] iodide administration dramatically attenuated HNSCC tumor formation in athymic mice.Conclusions.Our data demonstrate the feasibility of genetically targeted radiotherapy by use of the NIS gene as a possible therapeutic intervention in head and neck cancer. © 2004 Wiley Periodicals, Inc. Head Neck 26: 265–271, 2004
mTHPC‐mediated photodynamic therapy in patients with advanced, incurable head and neck cancer: a multicenter study of 128 patients
Authors: D'Cruz Anil K. , Robinson Martin H. , Biel Merrill A. 
Published: March 2004

AbstractBackground.The aim of this multicenter study was to assess tumor response, clinical quality‐of‐life benefit, survival, and safety after treatment with mTHPC in patients with recurrent/refractory squamous cell carcinoma of the head and neck unsuccessfully treated or unsuitable for treatment with conventional modalities.Methods.One hundred twenty‐eight patients were treated with mTHPC followed, 96 hours later, by illumination of the tumor surface with 652‐nm laser light. Tumor response was assessed with WHO criteria and tumor mass reduction from baseline. Clinical quality‐of‐life benefit was based on the University of Washington Quality‐of‐Life questionnaire.Results.By use of WHO criteria, 38% of evaluable patients achieved an overall tumor response, and 16% achieved a complete tumor response. Forty‐three percent of assessable lesions achieved 100% tumor mass reduction, and 58% achieved 50% or greater tumor mass reduction. Fifty‐three percent of evaluable patients experienced significant clinical quality‐of‐life benefit. Subset analyses revealed two subgroups in which significantly better responses were seen in patients with tumors 10 mm or less in depth and patients with fully illuminated lesions. In patients fulfilling both categories, overall tumor response was 54%, complete tumor response was 30%, and 61% demonstrated significant clinical quality‐of‐life benefit. Median survival was significantly better in responders. No major toxicities were detected.Conclusions.Patients with advanced cancer of the head and neck, who have exhausted other treatment options, can achieve significant clinical benefit and improvement in quality of life with mTHPC. © 2004 Wiley Periodicals, Inc. Head Neck 26: 232–240, 2004
Postoperative brachytherapy alone and combined postoperative radiotherapy and brachytherapy boost for squamous cell carcinoma of the oral cavity, with positive or close margins
Authors: Lapeyre Michel , Bollet Marc A. , Racadot Severine , Geoffrois Lionnel , Kaminsky Marie‐Christine , Hoffstetter Sylvette , Dolivet Gilles , Toussaint Bruno , Luporsi Elisabeth , Peiffert Didier 
Published: March 2004

AbstractBackground.Postoperative radiotherapy is necessary for squamous cell carcinoma (SCC) of the oral cavity with positive or close margins. The aim of the study is to define the indications of postoperative brachytherapy (BRT).Methods.From 1979 to 1993, 82 patients with positive or close margins had postoperative BRT (58 T1–2, 24 T3–4, 45 mobile tongue, 37 floor of mouth). Forty‐six patients had combined radiotherapy (RT) with a mean dose of 48 Gy, and BRT boost with a mean dose of 24 Gy. Thirty‐six patients had BRT alone with a mean dose of 60 Gy. BRT was performed with interstitial low dose rate Iridium 192.Results.Overall survival (OS), cause‐specific survival (CSS), and local control (LC) at 5 years were, respectively, for T1–2/N0N− with BRT, 75%, 85%, and 88%,and with RT‐BRT 70%, 92%, and 92%; for T1–2/N+ with RT‐BRT, 44%, 67%, and 78%; for T3–4/N− with RT‐BRT, 42%, 90%, and 80%; and for T3–4/N+ with RT‐BRT, 22%, 43%, and 57%. Prognostic factors for OS, CSS, and LC were N+ (p ≤ .009), extracapsular spread (ECS+;p ≤ .000001), and T stage for LC only (p = .02). Prognostic factors for complications were a high number of wires with a cutoff at five wires (p = .008), a high dose rate with a cutoff at 0.57 Gy/hr (p = .01), and a high total dose (BRT + RT) with a cutoff at 71 Gy (p = .07).Conclusions.BRT alone for SCC T1–2/N0N− is better than RT‐BRT because, with equivalent results, it avoids the adverse events of postoperative RT (xerostomia) and permits the treatment of a second head and neck primary in nonirradiated tissue. The results for the T3–4/N− are acceptable with this approach (ie, RT‐BRT) but may be improved for N+. © 2004 Wiley Periodicals, Inc. Head Neck 26: 216–223, 2004