bluuebunny/crossref_metadata_2025 huggingface dataset:
Perivascular epithelioid cell tumor (PEComa) of the uterine cervix associated with intraabdominal "PEComatosis": A clinicopathological study with comparative genomic hybridization analysis
Authors: Fadare Oluwole , Parkash Vinita , Yilmaz Yesim , Mariappan M Rajan , Ma Linglei , Hileeto Denise , Qumsiyeh Mazin B , Hui Pei
Published: October 2004

Background

The World Health Organization recently recognized a family of neoplasms showing at least partial morphological or immunohistochemical evidence of a putative perivascular epithelioid cell (PEC) differentiation. These tumors include angiomyolipoma (AML), clear cell "sugar" tumors of the lung (CCST), lymphangioleiomyomatosis (LAM), clear cell myomelanocytic tumors of the falciform ligament and distinctive clear cell tumors at various other anatomic sites.

Case presentation & methods

A 41-year old gravida-1 para-1 with tuberous sclerosis presented with an incidentally identified 2.2 cm mass. The morphology and immunohistochemical profile was consistent with PEComa. Distinct aggregates of HMB-45 epithelioid cells were present in an occasionally distinctive perivascular distribution in the myometrium, small bowel lamina propria and ovarian hila. These distinctive aggregates, for which we propose the designation "PEComatosis" based on their intraabdominal distribution, did not display cytological atypia, mitotic activity or necrosis. CGH and DNA ploidy analysis showed a balanced chromosomal profile and diploid nuclei, respectively. There was no recurrence or metastases at 35 months' follow-up. Fifty-one previously reported cases of non-AML, LAM and CCST PEComas [perivascular epithelioid cell tumors- not otherwise specified (PEComa-NOS)] are reviewed.

Conclusions

The lesions may be a reflection of tumor multicentricity, in which each may be a potential nidus for the development of future more well-developed tumors. Alternatively, they may be a manifestation of a poorly understood "field effect", in which there is an increased propensity to develop tumors of this type throughout the abdomen. Finally, and least likely in our opinion, they may represent tumor spread from its primary site.
Rupture of totally implantable central venous access devices (Intraports) in patients with cancer: report of four cases
Authors: Filippou Dimitrios K , Tsikkinis Christoforos , Filippou Georgios K , Nissiotis Athanasios , Rizos Spiros
Published: October 2004

Background

Totally implantable central venous access devices (intraports) are commonly used in cancer patients to administer chemotherapy or parenteral nutrition. Rupture of intraport is a rare complication.

Patients and methods

During 3 years period, a total of 245 intraports were placed in cancer patients for chemotherapy. Four of these cases (two colon cancer and one each of pancreas and breast cancer) had rupture of the intraport catheter, these forms the basis of present report.

Results

Mean time insitu for intraports was 164∀35 days. Median follow-up time was 290 days and total port time in situ was 40180 days. The incidence of port rupture was 1 per 10,000 port days.

Three of the 4 cases were managed by successful removal of catheters. In two of these the catheter was removed under fluoroscopic control using femoral route, while in the third patient the catheter (partial rupture) was removed surgically. One of the catheters could not be removed and migrated to right ventricle on manipulations.

Conclusion

Port catheter rupture is a rare but dreaded complication associated with subcutaneous port catheter device placement for chemotherapy. In case of such an event the patient should be managed by an experienced vascular surgeon and interventional radiologist, as in most cases the ruptured catheter can be retrieved by non operative interventional measures.
The structure of biodiversity – insights from molecular phylogeography
Authors: Hewitt Godfrey M
Published: October 2004

DNA techniques, analytical methods and palaeoclimatic studies are greatly advancing our knowledge of the global distribution of genetic diversity, and how it evolved. Such phylogeographic studies are reviewed from Arctic, Temperate and Tropical regions, seeking commonalities of cause in the resulting genetic patterns. The genetic diversity is differently patterned within and among regions and biomes, and is related to their histories of climatic changes. This has major implications for conservation science.
Identification of a novel tumor necrosis factor α-responsive region in the NCF2 promoter
Authors: Gauss Katherine A , Bunger Peggy L , Larson Trina C , Young Catherine J , Nelson-Overton Laura K , Siemsen Daniel W , Quinn Mark T
Published: October 2004

The phagocyte reduced nicotinamide adenine dinucleotide phosphate oxidase is a multiprotein enzyme that catalyzes the production of microbicidal oxidants. Although oxidase assembly involves association of several membrane and cytosolic oxidase proteins, one of the cytosolic cofactors, p67phox, appears to play a more prominent role in final activation of the enzyme complex. Based on the importance of p67phox, we investigated transcriptional regulation of the p67phox gene [neutrophil cytosolic factor 2 (NCF2)] and demonstrated previously that activator protein-1 (AP-1) was essential for basal transcriptional activity. As p67phox can be up-regulated by tumor necrosis factor α (TNF-α), which activates AP-1, we hypothesized that TNF-α might regulate NCF2transcription via AP-1. In support of this hypothesis, we show here that NCF2 promoter-reporter constructs are up-regulated by TNF-α but only when AP-1 factors were coexpressed. Consistent with this observation, we also demonstrate that NCF2 mRNA and p67phox protein are up-regulated by TNF-α in various myeloid cell lines as well as in human monocytes. It was surprising that mutagenesis of the AP-1 site in NCF2 promoter constructs did not eliminate TNF-α induction, suggesting additional elements were involved in this response and that AP-1 might play a more indirect role. Indeed, we used NCF2 promoter-deletion constructs to map a novel TNF-α-responsive region (TRR) located between −56 and −16 bp upstream of the translational start site and demonstrated its importance in vivo using transcription factor decoy analysis. Furthermore, DNase footprinting verified specific binding of factor(s) to the TRR with AP-1 binding indirectly to this region. Thus, we have identified a novel NCF2 promoter/enhancer domain, which is essential for TNF-α-induced up-regulation of p67phox.
MUC1 (CD227) interacts with lck tyrosine kinase in Jurkat lymphoma cells and normal T cells
Authors: Mukherjee P , Tinder T L , Basu G D , Gendler S J
Published: October 2004

MUC1 (CD227) is a large transmembrane epithelial mucin glycoprotein, which is aberrantly overexpressed in most adenocarcinomas and is a target for immune therapy for epithelial tumors. Recently, MUC1 has beendetected in a variety of hematopoietic cell malignancies including T and B cell lymphomas and myelomas; however, its function in these cells is not clearly defined. Using the Jurkat T cell lymphoma cell line and normal human T cells, we demonstrate that MUC1 is not only expressed in these cells but is also phosphorylated upon T cell receptor (TCR) ligation and associates with the Src-related T cell tyrosine kinase, p56lck. Upon TCR-mediated activation of Jurkat cells, MUC1 is found in the low-density membrane fractions, where linker of T cell activation is contained. Abrogation of MUC1 expression in Jurkat cells by MUC1-specific small interfering RNA resulted in defects in TCR-mediated downstream signaling events associated with T cell activation. These include reduction in Ca2+ influx and extracellular signal-regulated kinase 1/2 phosphorylation, leading to a decrease in CD69 expression, proliferation, and interleukin-2 production. These results suggest a regulatory role of MUC1 in modulating proximal signal transduction events through its interaction with proteins of the activation complex.
Proposed Treatment Strategy for Cavernous Sinus Meningiomas: A Prospective Study
Authors: Maruyama Keisuke , Shin Masahiro , Kurita Hiroki , Kawahara Nobutaka , Morita Akio , Kirino Takaaki
Published: October 2004

OBJECTIVE:

To establish a safe and effective treatment strategy for cavernous sinus (CS) meningiomas, we prospectively analyzed the outcome of a treatment protocol combining surgery and radiosurgery during the past 7 years.

METHODS:

Tumors confined to the CS and distant from the optic apparatus and the brainstem were treated with radiosurgery alone. Tumors attached to or compressing the optic apparatus and brainstem and that were larger than 3 cm in mean diameter, extended into the multiple cranial fossae, and were suspected of being malignant were treated with combined nonradical microsurgery and radiosurgery.

RESULTS:

In accordance with this treatment protocol, 40 patients aged 26 to 72 years (median, 51 yr) with primary (n = 27) or recurrent (n = 13) CS meningiomas (volume range, 0.9–39.3 cm3; median volume, 5.4 cm3) were treated with combined surgery and radiosurgery (n = 23) or radiosurgery alone (n = 17). During radiosurgery, 12 to 18 Gy (median, 16 Gy) was delivered to the tumor margin. The follow-up period ranged from 14 to 79 months (median, 47 mo). The actuarial tumor control rate was 94.1% at 5 years. The improvement of cranial nerve function was significantly frequent in patients with primary CS meningiomas (P< 0.05). Permanent cranial nerve dysfunction was significantly frequent in patients with tumors compressing the brainstem or smaller than 10 cm3 (P< 0.05). All 36 patients with a pretreatment Karnofsky Performance Scale score of 90 or more maintained the same range after treatment.

CONCLUSION:

Proper combination of microsurgery and radiosurgery for CS meningiomas provides excellent growth control with favorable functional state. Outcomes were better when this protocol was adopted at the initial diagnosis for patients with smaller tumors that did not compress the brainstem.
Spastic Equinus Foot: Multicenter Study of the Long-term Results of Tibial Neurotomy
Authors: Buffenoir Kevin , Roujeau Thomas , Lapierre Françoise , Menei Philippe , Menegalli-Boggelli Dominique , Mertens Patrick , Decq Philippe
Published: October 2004

OBJECTIVE:

Tibial neurotomy is a surgical technique widely used for the treatment of spastic equinus foot, but it has rarely been evaluated. The primary objective of this prospective study was to provide an objective quantification of the long-term results of tibial neurotomy.

METHODS:

This multicenter prospective study was conducted from 1999 to 2003. Fifty-five patients with spastic equinus foot were treated in five neurosurgical centers. Preoperative and postoperative clinical evaluation comprised description of the foot deformity, study of stretch reflexes, evaluation of the repercussions of the deformity, and gait analysis. Selective neurotomy was performed in all patients.

RESULTS:

No postoperative complications were observed. The mean postoperative follow-up was 10 months. Tibial neurotomy improved the appearance of the foot (equinus and varus deformities, claw toes); the equinus score decreased from 1.54 to 0.273 after the operation. Stretch reflex scores were decreased significantly and for a long term after surgery; the mean triceps surae stretch reflex score decreased from 2.46 to 0.47. The angle of passive dorsiflexion of the ankle increased significantly (from −0.56 degrees to +6.85 degrees). Gait analysis demonstrated a statistically significant increase in the speed of the patient's gait after surgical treatment; the time taken by the patient to walk 10 m at a normal speed in shoes decreased from a mean of 55 seconds to 35.16 seconds. Postoperatively, 92.7% of preoperative objectives had been achieved.

CONCLUSION:

Tibial neurotomy ensures long-term functional improvement of patients with spastic equinus foot. It provides a lasting response for these patients compared with other, more transient treatments.
Ulnar Nerve Entrapment Neuropathy at the Elbow: Simple Decompression
Authors: Huang Jason H. , Samadani Uzma , Zager Eric L.
Published: October 2004

ULNAR NERVE ENTRAPMENT neuropathy at the elbow, or the cubital tunnel syndrome, is frequently encountered in neurosurgical practice as the second most common peripheral nerve entrapment after carpal tunnel syndrome. Patients typically present with weakness or atrophy of the hand as well as paresthesias in the ulnar nerve distribution. The diagnosis can be confirmed with a careful clinical examination and electrophysiological studies. Patients who have failed conservative therapy are considered for surgery. Although a number of surgical options are available, simple decompression of the ulnar nerve can achieve satisfactory results with appropriate patient selection. We describe the relevant anatomy and surgical techniques for simple in situ decompression of the ulnar nerve at the elbow.
Progressive Growth of a Giant Dolichoectatic Vertebrobasilar Artery Aneurysm after Complete Hunterian Occlusion of the Posterior Circulation: Case Report
Authors: O'shaughnessy Brian A. , Getch Christopher C. , Bendok Bernard R. , Parkinson Richard J. , Batjer H Hunt
Published: October 2004

OBJECTIVE AND IMPORTANCE:

Dolichoectatic vertebrobasilar artery aneurysms are often extremely difficult, if not impossible, to treat with microneurosurgical clip reconstruction. As such, a Hunterian strategy via vertebral or basilar artery sacrifice is often used. We have encountered a patient in whom deliberate bilateral vertebral artery sacrifice was insufficient to avoid progressive expansion of a giant dolichoectatic vertebrobasilar artery aneurysm. On the basis of a review of the literature, we are unaware of another reported case.

CLINICAL PRESENTATION:

A 60-year-old man presented with signs and symptoms of brainstem compression from a large fusiform aneurysm involving the distal dominant vertebral and proximal basilar arteries. Results of angiographic evaluation were highly characteristic of underlying dolichoectasia.

INTERVENTION:

The patient was treated initially with staged bilateral vertebral artery occlusion and adjunctive posterior circulation revascularization. After this therapy failed, he underwent a trapping procedure and aneurysm deflation.

CONCLUSION:

Unclippable aneurysms of the vertebrobasilar system are formidable lesions. They are not uniformly treatable by direct surgical reconstruction, and their growth is not consistently stabilized by the implementation of a complete Hunterian strategy. Future developments related to the use of endovascular stent technology may offer a more successful treatment approach for patients with these complex cerebrovascular lesions.
Three-dimensionally Reconstructed Magnetic Source Imaging and Neuronavigation in Pediatric Epilepsy: Technical Note
Authors: Holowka Stephanie A. , Otsubo Hiroshi , Iida Koji , Pang Elizabeth , Sharma Rohit , Hunjan Amrita , Xiang Jiang , Snead O Carter , Chuang Nathaniel A. , Chuang Sylvester H. , Rutka James T.
Published: October 2004

OBJECTIVE:

To determine the role of reconstructing three-dimensional magnetic source imaging (MSI) data on cortical resections for children undergoing epilepsy surgery using neuronavigation.

METHODS:

Magnetoencephalographic recordings were analyzed in 16 children under 18 years of age with intractable epilepsy. The data were transferred to the neuronavigation workstation for intraoperative localization of MSI spike sources in selected patients. With the aid of neuronavigation, the MSI spike sources were resected. Intraoperative electrocorticography was then used to survey the surrounding field for residual epileptiform activity.

RESULTS:

MSI spike sources were obtained in 13 of 16 patients. MSI spike sources localized the cortical and subcortical discharges before intraoperative electrocorticography in nine patients and before extraoperative subdural grid electroencephalographic monitoring in four patients. The localization of MSI spikes sources was characterized by clustered spike sources in 10 patients. By use of neuronavigation, the clustered spike sources were correlated to the interictal zone indicated by intraoperative electrocorticography in six patients and to the ictal onset zone shown on extraoperative subdural grid electroencephalography in three patients. Cortical excision of the spike cluster focus was then performed in these six patients. The technique used here to resect MSI spike source clusters that correlate with the ictal onset zone by invasive subdural grid monitoring is illustrated in one patient who underwent cortical resection for epilepsy surgery.

CONCLUSION:

Three-dimensional reconstruction of MSI data linked to neuronavigation is a promising technique to facilitate resections around eloquent cortex in children with epilepsy.
An Anthropomorphic Phantom Study of the Accuracy of CyberKnife Spinal Radiosurgery
Authors: Yu Cheng , Main William , Taylor David , Kuduvalli Gopinath , Apuzzo Michael L.J. , Adler John R. , Wang Michael Y.
Published: October 2004

OBJECTIVE:

Stereotactic radiosurgery requires the highest degree of accuracy in target identification and localization. When targeting paraspinal lesions, the CyberKnife radiosurgical system (Accuray, Inc., Sunnyvale, CA) uses implanted stainless steel fiducials. The purpose of this study was to evaluate the total system for clinically relevant accuracy of this approach.

METHODS:

The clinically relevant accuracy of the CyberKnife depends on 1) the accuracy of beam delivery, which in turn represents a compilation of robot and camera image-tracking errors, and 2) the inherent accuracy of target localization that stems from computed tomographic imaging and treatment planning. The clinically relevant accuracy was measured at three different CyberKnife facilities using head and torso phantoms loaded with packs of radiochromic film and expressed as a displacement of the dose contours from the treatment planning.

RESULTS:

The mean clinically relevant error, as measured at three different CyberKnife facilities, was determined to be 0.7 ± 0.3 mm, which did not vary with computed tomographic slice thickness in a range of 0.625 to 1.5 mm. The average treatment delivery precision was 0.3 ± 0.1 mm. Fiducial tracking error was less than 0.3 mm for radial translations up to 14 mm and less than 0.7 mm for rotations up to 4.5 degrees.

CONCLUSION:

For the treatment of relatively stationary spinal lesions targeted with fiducial tracking, the CyberKnife system is capable of submillimeter accuracy.
Pseudotumor Cerebri Patients with Shunts from the Cisterna Magna: Clinical Course and Telemetric Intracranial Pressure Data
Authors: Lee Max C. , Yamini Bakhtiar , Frim David M.
Published: October 2004

OBJECTIVE:

Shunting of cerebrospinal fluid (CSF) to an extracranial site is the mainstay of treatment of absorptive hydrocephalus and pseudotumor cerebri. On occasion, both lateral ventricles and the lumbar space become unsuitable for placement of a functioning CSF drainage catheter. We have encountered several such patients and describe our strategy of shunting from the cisterna magna to the pleural space or cardiac atrium.

METHODS:

We report a retrospective review of the clinical course of five patients with cisternal shunts and intracranial pressure telemonitoring devices.

RESULTS:

Cisternal shunting was able to successfully drain CSF to a normal pressure in all five patients. CSF pressure data collected from those patients indicate that the CSF pressure dynamics in cisternal shunts is similar to that of ventricular shunts. However, the cisternal shunting and subsequent high revision rate did result in a significant number of complications and two shunt infections.

CONCLUSION:

Shunting CSF from the cisterna magna in the absence of another suitable drainage site does result in acceptable reduction of elevated intracranial pressure. However, the technique is associated with a high complication rate that may reflect the population of patients in whom this technique is required.
Missile-caused Ulnar Nerve Injuries: Outcomes of 128 Repairs
Authors: Roganovic Zoran
Published: October 2004

OBJECTIVE:

This prospective study presents repair results after missile-caused ulnar nerve ruptures as well as factors influencing the outcomes.

METHODS:

Between 1991 and 1994, 128 casualties with missile-caused complete ulnar nerve injury were managed surgically in the Neurosurgical Department of the Belgrade Military Medical Academy. At least 4 years after surgery, we scored sensorimotor recovery, neurophysiological recovery, and patient judgment of the outcome. On the basis of the total score, we defined the final outcome as poor, insufficient, good, or excellent. The last two outcomes were considered to be successful.

RESULTS:

A successful outcome was obtained in 0% of high-level, 33.8% of intermediate-level, and 77.3% of low-level repairs (P< 0.001). On average, the nerve defect, preoperative interval, and patient age were lower for patients with a successful outcome than for those with an unsuccessful outcome (P= 0.004, P= 0.032, and P= 0.003, respectively). Worsening of the outcome was related to nerve defect longer than 4.5 cm, preoperative interval longer than 5.5 months, and age older than 23 years (P= 0.002, P= 0.034, and P= 0.023, respectively). A successful outcome occurred in 48.8% of patients repaired with direct suture and in 41.2% of patients repaired with a nerve graft (P> 0.05). A successful outcome also occurred 22.2% of combined ulnar-median nerve repairs and in 49.5% of isolated ulnar nerve repairs (P= 0.011). Repair level (P< 0.001), preoperative interval (P= 0.001), length of the nerve defect (P< 0.001), and associated median nerve rupture (P= 0.028) were independent predictors of a successful outcome.

CONCLUSION:

The outcome of ulnar nerve repair depends significantly on the repair level, preoperative interval, associated median nerve injury, length of the nerve defect, and age of the patient. High-level ulnar nerve repair is probably useless if performed in the classic manner.
Plasma F2-Isoprostanes and Coronary Artery Calcification: The CARDIA Study
Authors: Gross Myron , Steffes Michael , Jacobs David R , Yu Xinhua , Lewis Linda , Lewis Cora E , Loria Catherine M
Published: October 2004

Background: Oxidation of lipids in lipoproteins and cells may initiate and enhance the early development of cardiovascular disease.

Method and Results: We assayed F2-isoprostanes, oxidation products of arachidonic acid, by gas chromatography–mass spectrometry in a biracial cohort of 2850 young healthy adult men and women. Coronary artery calcification (CAC), a component of coronary artery atherosclerosis, was detectable in 10% of the cohort and appeared to be in its initial stages (Agatston scores <20 in 47% and <100 in 83% of CAC-positive participants). After adjusting for sex, clinical site, age, and race, the presence of any CAC was 24% more likely among those with high vs low concentrations of F2-isoprostanes [odds ratio (OR) = 1.24 per 92.2 pmol/L (32.7 ng/L; 1 SD of F2-isoprostanes); 95% confidence interval (CI), 1.09–1.41]. The OR was only slightly attenuated [1.18 per 92.2 pmol/L (32.7 ng/L); CI, 1.02–1.38] after further adjustment for body mass index, smoking, serum lipids, C-reactive protein, antioxidant supplementation use, diabetes, and blood pressure. As a continuous variable, the Agatston score increased by 6.9% per 92.2 pmol/L (32.7 ng/L) of F2-isoprostane concentration (P <0.01). Whereas CAC prevalence was lower in women than men, mean (SD), F2-isoprostanes were higher in women {190 (108.9) pmol/L [67.4 (38.6) ng/L]} than in men {140.4 (55.6) pmol/L [49.8 (19.7) ng/L]}. Nevertheless, F2-isoprostanes were associated with an increased risk of CAC in both sexes.

Conclusion: This association between increased concentrations of circulating F2-isoprostanes and CAC in young healthy adults supports the hypothesis that oxidative damage is involved in the early development of atherosclerosis.
Liver Dysfunction and Steatosis in Familial Hypobetalipoproteinemia
Authors: Whitfield Amanda J , Barrett P Hugh R , Robertson Ken , Havlat Marek F , van Bockxmeer Frank M , Burnett John R
Published: October 2004

A 32-year-old man presented with increases in serum alanine aminotransferase activity, iron concentration, and transferrin saturation, suggestive of hepatic dysfunction and iron overload. In addition, he had unusually low plasma concentrations of LDL-cholesterol and apolipoprotein (apo) B. Hepatic ultrasonography was consistent with fatty liver. On liver biopsy, marked steatosis and moderate to marked iron deposition were observed. The patient was found to carry the HFE C282Y and H63D mutations, which are associated with hereditary hemochromatosis, and the α1-antitrypsin PiZ variant. An immunoblot of plasma for apoB showed the presence of a truncated apoB species, indicative of familial hypobetalipoproteinemia. DNA sequence analysis revealed that the patient was heterozygous for the apoB-80.5 (c.11040T>G) mutation. This unique case shows an unusual combination of underlying disorders that could all be contributing to liver dysfunction and fatty liver.
Panel of Genes Transcriptionally Up-regulated in Squamous Cell Carcinoma of the Cervix Identified by Representational Difference Analysis, Confirmed by Macroarray, and Validated by Real-Time Quantitative Reverse Transcription-PCR
Authors: Sgarlato Gregory D , Eastman Catharine L , Sussman Howard H
Published: October 2004

Background: The Pap smear is currently the most widely used method of screening for squamous cell carcinoma of the cervix (SCCC). Because it is based on cell morphology, it is subject to variability in interpretation. Sensitive molecular markers capable of differentiating cancerous samples from noncancerous ones would be beneficial in this regard.

Methods: We performed representational difference analysis (RDA) using paired, noncancerous (normal) and cancerous (disease) tissues taken from the same specimen obtained from a single patient with a confirmed diagnosis of SCCC. Linearly amplified cDNA from normal and diseased tissues of the original patient and seven others were hybridized to DNA macroarrays containing the candidate gene transcript fragments. Real-time quantitative reverse transcription-PCR was used to validate the macroarray results.

Results: RDA identified a candidate pool of 65 transcript fragments up-regulated in diseased tissue compared with normal tissue. Forty-one transcripts were found to be up-regulated in diseased compared with normal tissue in at least one half the patients by macroarray hybridization. Eleven of those genes were selected for real-time quantitative reverse transcription-PCR analysis, and all were confirmed as transcriptionally up-regulated in cancer compared with normal tissue in at least one half the patients.

Conclusions: RDA using tissues from a single patient identified gene fragments confirmed to be transcriptionally up-regulated in SCCC both in the original patient and in seven others. The confirmed genes have a variety of functions and also have the potential to serve as diagnostic or prognostic markers.
Modellierung und Zustandsbeobachtung von Simulated-Moving-Bed Prozessen (Modelling and State Observation of Simulated Moving Bed Processes)
Authors: Kleinert Tobias , Lunze Jan
Published: October 2004

Dieser Beitrag stellt einen neuen Ansatz zur Modellierung und Zustandsbeobachtung von chromatographischen Simulated-Moving-Bed (SMB) Prozessen vor. Ziel ist es, die aktuelle Form, Position und Bewegung der Konzentrationsprofile des SMB-Prozesses aus wenigen Konzentrationsmessungen zu bestimmen. Ausgehend von der stationären Lösung des Modells des wahren Gegenstroms wird ein Formansatz zur Modellierung der Wellenfronten vorgestellt. Die Parameter der Wellenfronten werden als Zustandsvariable interpretiert, für die ein zeitdiskretes Zustandsraummodell abgeleitet wird. Es wird ein Beobachter vorgeschlagen, der diese Parameter aus den verfügbaren Messwerten bestimmt. Simulationsergebnisse zeigen die Güte des Beobachtungsergebnisses.
Iterativ lernende Regelungen für Semi-Batchprozesse (Iterative Learning Control Algorithms for Semi Batch Processes)
Authors: Hengen Heiko , Breitel Torsten , Pandit Madhukar
Published: October 2004

Iterativ lernende Regelungen eignen sich zur Beherrschung zyklischer Prozesse mit nichtverschwindenden Zwischenzyklenzeiten. Bei den Semibatch- bzw. Semibatch-Mehrstoff-Prozessen liegt ein Prozess vor, der sich im Ablauf zwar wiederholt, jedoch mit unterschiedlichen Ausgangsstoffen arbeitet. Im Unterschied zum reinen Batch-Prozess werden Edukte auch während der laufenden Reaktion zugegeben. Speziell bei chemischen Semibatchprozessen kommt noch hinzu, dass der verwendete Reaktor nicht notwendigerweise nach jedem Batch gereingt werden kann, sodass sich bestimmte Reaktorparameter von Zyklus zu Zyklus ändern. Der im vorliegenden Aufsatz dargestellte ILR-Ansatz behandelt genau diese Schwierigkeiten durch Einführung eines speziellen Speichers, der abhängig vom gefahrenen Produkt und Verschmutzungsgrad des Reaktors arbeitet. Das dargestellte Regelverfahren wurde als Referenz anhand des Chylla-Haase-Modells erprobt.
Regelung eines hybriden Positioniersystems (Control of a Hybrid Positioning System)
Authors: Denkena Berend , Imiela Joachim , Kallage Franz
Published: October 2004

Im Bereich des “High Speed Machining” werden verstärkt hochdynamische Lineardirektantriebe eingesetzt. Neuartige Maschinenkonzepte stoßen jedoch an die Grenzen der dynamischen Bandbreite dieses Antriebskonzeptes. Die Erhöhung der dynamischen Positioniergenauigkeit des Linearantriebs wird mit der Verwendung von Zusatzaktoren in einem Hybridantrieb ermöglicht. In diesem Beitrag werden der Aufbau, die Regelung und die Möglichkeiten eines redundanten Antriebskonzeptes, bestehend aus einem Lineardirektantrieb und einem Magnetaktor, dargestellt.
Mandibular Widening by Distraction Osteogenesis in the Treatment of a Constricted Mandible and Telescopic Bite
Authors: Kita Hiroki , Kochi Shoko , Yamada Atsushi , Imai Yoshimichi , Konno Noriaki , Saitou Chihiro , Mitani Hideo
Published: October 2004

Objective

Documentation of the application of mandibular widening by distraction osteogenesis and orthodontics.

Patients

Three patients with telescopic bite resulting from an extremely constricted mandible related to hypoglossia-hypodactyly syndrome.

Intervention

Mandibular widening by distraction osteogenesis using an extraoral device and subsequent orthodontic treatment.

Results

The extremely constricted mandible and telescopic bite were dramatically improved by mandibular widening using distraction osteogenesis and subsequent orthodontics. Two of the three patients had transient complications; one reported temporomandibular joint pain and the other showed evidence of periodontal damage.

Conclusion

Mandibular widening by distraction osteogenesis is an effective technique for the treatment of telescopic bite resulting from an extremely constricted mandible.
Dental Maturation in Children with Shunt-Treated Hydrocephalus
Authors: Pirttiniemi P. , Poikela A. , Huggare J. , Löppönen T.
Published: October 2004

Objective

The aim of this study was to examine the relationship between dental maturation and somatic development and to discover their possible deviations in children with shunt-treated hydrocephalus.

Design

Radiographs (orthopantomogram and hand-wrist radiograph) from children with shunt-treated hydrocephalus were analyzed with respect to the dental maturation and compared with values of an age- and sex-matched control group and population standards.

Patients

Forty-one children with shunt-treated hydrocephalus (27 boys and 14 girls) aged from 5 to 16 years (median age 11.0 years).

Results

The mean deviation of dental age from chronological age was significantly greater in the hydrocephalic group than in the control group. The mean value of dental age deviation was advanced in early pubertal stages but reduced in later pubertal stages.

Conclusions

These findings can be explained by changes in the endocrinological conditions, which are due to disturbed pituitary secretion. The present results could also partly reflect an adaptable developmental pathway in an otherwise strictly genetically determined process.
Three-Dimensional Facial Characteristics of Caucasian Infants without Cleft and Correlation with Body Measurements
Authors: White Jill E. , Ayoub Ashraf F. , Hosey Marie-Therese , Bock Mitchum , Bowman Adrian , Bowman Janet , Siebert J. Paul , Ray Arup
Published: October 2004

Objective

The aim of this study was to characterize the soft tissue facial features of infants without cleft and to report on the correlation between these with weight, length, and head circumference.

Design

This was a prospective study using a noninvasive three-dimensional (3D) stereophotogrammetry (C3D) system to capture the images of the participants. Landmarks were identified on the 3D facial images. Means and SDs were derived for facial distances and angles. A facial asymmetry score was calculated for each image. Two sample Student's t tests, Pearson's correlation coefficients and analysis of covariance were used to ascertain any gender differences and determine whether these could be explained by weight differences.

Participants

Eighty-three infants, 41 boys and 42 girls, were captured at rest with their lips apart, at approximately 3 months of age.

Results

Significant sex differences, of 1 to 2 mm, were found in several facial dimensions, such as face height and nose width. The larger facial measurements correlated significantly with body measurements. Analysis of variance confirmed these differences could be explained by differences in weight. There were no sex differences in the nose/mouth width ratios or in any of the angles measured, suggesting that there may be little sex difference in shape. A slight degree of asymmetry in the faces of infants without cleft was detected.

Conclusions

Comparisons between noncleft controls and infants with cleft should take cognizance of normal age and sex variations in height and weight that occur among infants.
Descriptive Epidemiology of Oral Clefts in a Multiethnic Population, Hawaii, 1986–2000
Authors: Forrester Mathias B. , Merz Ruth D.
Published: October 2004

Objective

To describe the relationship between oral clefts and demographic and clinical factors in Hawaii.

Methods

Data were obtained from a birth defects registry and included all infants and fetuses with oral clefts delivered during 1986 through 2000. Subjects were categorized as total, isolated, and nonisolated cleft lip with or without cleft palate (CL±P) or cleft palate without cleft lip (CP).

Results

There were 352 total subjects of CL±P and 192 total subjects of CP with corresponding rates per 10,000 live births of 12.5 for CL±P and 6.8 for CP. Total, isolated, and nonisolated CL±P rates demonstrated no clear pattern by maternal age. The total and nonisolated CP rates tended to be higher among older maternal age groups. The total CL±P rate was higher among Far East Asians, Pacific Islanders, and Filipinos than among whites. The total CP rate was higher among Far East Asians and Pacific Islanders than among whites, whereas the rate for Filipinos was lower than for whites. The total CL±P rate was substantially lower among females (rate ratio 0.62, 95% confidence interval [CI] = 0.49 to 0.77) and the total CP rate substantially higher among females (rate ratio 1.52, 95% CI = 1.13 to 2.06). Both CL±P and CP were more common with lower birth weight and gestational age among the total, isolated, and nonisolated groups.

Conclusions

Oral cleft risk was associated with maternal race/ethnicity, sex, birth weight, and gestational age. Although some of the observed associations were consistent with the literature, others were not.
Photographs of Study Casts: An Alternative Medium for Rating Dental Arch Relationships in Unilateral Cleft Lip and Palate
Authors: Nollet Pieter J. P. M. , Katsaros Christos , van 't Hof Martin A. , Bongaarts Catharina A. M. , Semb Gunvor , Shaw William C. , Kuijpers-Jagtman Anne Marie
Published: October 2004

Objective

To investigate the reliability of using photographs of study casts as an alternative to casts for rating dental arch relationships.

Design

Repeated-measures study.

Setting

Cleft Palate Center of the University Medical Center Nijmegen, Nijmegen, The Netherlands.

Patients

Records of children with complete unilateral cleft lip and palate (UCLP) (n = 49) at the age of 9 years were included.

Mean Outcome Measure(s)

Statistics of intra- and interexaminer agreement.

Results

No significant differences were found between the rating of dental casts and photographs of dental casts, using the Goslon Yardstick.

Conclusions

Photographs of dental casts provide a consistent, reproducible method for rating dental arch relationships in patients with UCLP at the age of 9 years and provide a reliable alternative to the application of the Goslon Yardstick on dental casts.
Seesaw Modification of the Lateral Orbital Wall in Le Fort III Osteotomy
Authors: Mavili M. Emin , Tunçbilek Gökhan
Published: October 2004

Objective

The traditional treatment for patients with syndromic craniosynostosis and midfacial retrusion has consisted of Le Fort III osteotomy and advancement. Distraction with rigid external systems allows advancement of the midface segment much more than the conventional methods. This excessive advancement resulted in the superiormost margin of the advancement segment becoming prominent. It can be felt easily with palpation and may influence the appearance of the patient negatively. This article presents a procedure osteotomy designed to modify the osteotomy lines at the lateral orbital rims and smooth the step deformity at the lateral canthal region.

Results

The seesaw osteotomy produced a smooth contour at the lateral orbital rim. Planned advancement was achieved without difficulty and without adverse long-term effects.
Effects of anti‐myosin drugs on anaphase chromosome movement and cytokinesis in crane‐fly primary spermatocytes
Authors: Silverman‐Gavrila Rosalind V. , Forer A.
Published: October 2004

To investigate whether myosin is involved in crane‐fly primary spermatocyte division, we studied the effects of myosin inhibitors on chromosome movement and on cytokinesis. With respect to chromosome movement, the myosin ATPase inhibitor 2,3‐butanedione 2‐monoxime (BDM) added during autosomal anaphase reversibly perturbed the movements of all autosomes: autosomes stopped, slowed, or moved backwards during treatment. BDM added before anaphase onset altered chromosome movement less than when BDM was added during anaphase: chromosome movements only rarely were stopped. They often were normal initially and then, if altered at all, were slowed. To confirm that the effects of BDM were due to myosin inhibition, we treated cells with ML‐7, a drug that inhibits myosin light chain kinase (MLCK), an enzyme necessary to activate myosin. ML‐7 affected anaphase movement only when added in early prometaphase: this treatment prevented chromosome attachment to the spindle. We treated cells with H‐7 as a control for possible non‐myosin effects of ML‐7. H‐7, which has a lower affinity than ML‐7 for MLCK but a higher affinity than ML‐7 for other potential targets, had no effect. These data confirm that the BDM effect is on myosin and indicate that the myosin used for chromosome movement is activated near the start of prometaphase. With respect to cytokinesis, BDM did not block furrow initiation but did block subsequent contraction of the contractile ring. When BDM was added after initiation of the furrow, the contractile ring either stalled or relaxed. ML‐7 blocked contractile ring contraction when added at all stages after autosomal anaphase onset, including when added during cytokinesis. H‐7 had no effect. These results confirm that the effects of BDM are on myosin and indicate that the myosin used for cytokinesis is activated starting from autosomal anaphase and continuing throughout cytokinesis. Cell Motil. Cytoskeleton 50:180–197, 2001. © 2001 Wiley‐Liss, Inc.
Calyculin‐A, an inhibitor for protein phosphatases, induces cortical contraction in unfertilized sea urchin eggs
Authors: Asano Yukako , Mabuchi Issei
Published: October 2004

When an unfertilized sea urchin egg was exposed to calyculin‐A (CL‐A), an inhibitor of protein phosphatases, for a short period and then lysed, the cortex contracted to exclude cytoplasm and became a cup‐shaped mass. We call the contracted cortex “actin cup” since actin filaments were major structural components. Electron microscopic observation revealed that the cup consisted of inner electron‐dense layer, middle microfilamentous layer, and outermost granular region. Microfilaments were heavily accumulated in the inner electron‐dense layer. The middle layer also contained numerous microfilaments, which were determined to be actin filaments by myosin S1 decoration, and they were aligned so that their barbed ends directed toward the outermost region. Myosin II, Arp2, Arp3, and spectrin were concentrated in the actin cup. Immuno‐electron microscopy revealed that myosin II was localized to the electron‐dense layer. We further found that the cortical tension of the egg increased just after application of CL‐A and reached maximum within 10 min. Cytochalasin B or butanedione monoxime blocked the contraction, which suggested that both actin filaments and myosin ATPase activity were required for the contraction. Myosin regulatory light chain (MRLC) in the actin cup was shown to be phosphorylated at the activation sites Ser‐19 and Thr‐18, by immunoblotting with anti‐phosphoepitope antibodies. The phosphorylation of MRLC was also confirmed by a 32P in vivo labeling experiment. The CL‐A‐induced cortical contraction may be a good model system for studying the mechanism of cytokinesis. Cell Motil. Cytoskeleton 48:245–261, 2001. © 2001 Wiley‐Liss, Inc.
Cardiac patterning and morphogenesis in zebrafish
Authors: Yelon Deborah
Published: October 2004

Development of the embryonic vertebrate heart requires the precise coordination of pattern formation and cell movement. Taking advantage of the availability of zebrafish mutations that disrupt cardiogenesis, several groups have identified key regulators of specific aspects of cardiac patterning and morphogenesis. Several genes, including gata5, fgf8, bmp2b, one‐eyed pinhead, and hand2, have been shown to be relevant to the patterning events that regulate myocardial differentiation. Studies of mutants with morphogenetic defects have indicated at least six genes that are essential for cardiac fusion and heart tube assembly, including casanova, bonnie and clyde, gata5, one‐eyed pinhead, hand2, miles apart, and heart and soul. Furthermore, analysis of the jekyll gene has indicated its important role during the morphogenesis of the atrioventricular valve. Altogether, these data provide a substantial foundation for future investigations of cardiac patterning, cardiac morphogenesis, and the relationship between these processes. © 2001 Wiley‐Liss, Inc.
The neuron–glia signal β‐neuregulin promotes Schwann cell motility via the MAPK pathway
Authors: Meintanis Stathis , Thomaidou Dimitra , Jessen Kristjan R. , Mirsky Rhona , Matsas Rebecca
Published: October 2004

Neuregulins constitute a family of related growth factors that play important roles in Schwann cell development and maturation. We investigated the involvement of β‐neuregulin in Schwann cell migration, using a simple in vitro bioassay. Pure Schwann cells were prepared from the sciatic nerves of 5‐day‐old rats and were grown in defined medium, with or without serum, until a monolayer of confluent cells was formed. A cell‐free area was then generated by inflicting a scratch resulting in a 1‐mm‐wide gap. Schwann cell migration within the gap was monitored microscopically at given time intervals and was quantified using an image analysis system. The extent of cell proliferation was estimated by BrdU incorporation, and cell migration was quantified both in the absence and presence of cytosine arabinoside. We found that, in the absence of serum, β‐neuregulin at a dose submaximal for proliferation increased the rate of Schwann cell migration by 84%. A more moderate effect was observed when β‐neuregulin was applied in the presence of serum which, however, is by itself responsible for increased Schwann cell motility. To assess the signal transduction pathways involved in this procedure we used one inhibitor of MAPK, PD098059, two inhibitors of PI‐3‐kinase, wortmannin, and LY0294002, and three different PKC inhibitors. Of these PD098059 inhibited the neuregulin‐induced enhancement in Schwann cell migration by 40%, the two PI‐3‐kinase inhibitors yielded an approximately 20% inhibition while the PKC inhibitors were ineffective. Our data indicate that the action of β‐neuregulin on Schwann cell motility is primarily mediated via the MAPK pathway. GLIA 34:39–51, 2001. © 2001 Wiley‐Liss, Inc.
Isolated human astrocytes are not susceptible to infection by M‐ and T‐tropic HIV‐1 strains despite functional expression of the chemokine receptors CCR5 and CXCR4
Authors: Boutet Agnès , Salim Hassan , Taoufik Yassine , Lledo Pierre‐Marie , Vincent Jean‐Didier , Delfraissy Jean‐François , Tardieu Marc
Published: October 2004

Within the brain, HIV‐1 targets the microglia and astrocytes. Previous studies have reported that viral entry into astrocytes is independent of CD4, in contrast to microglia. We aimed to determine whether chemokine receptors play a role in mediating CD4‐independent HIV‐1 entry into astrocytes. We found that embryonic astrocytes and microglial cells express CCR5, CCR3, and CXCR4 transcripts. Intracellular calcium levels in astrocytes were found to increase following application of RANTES, MIP‐1β (CCR5‐agonist), SDF‐1α (CXCR4‐agonist), but not eotaxin (CCR3‐agonist). In microglial cells, eotaxin was also able to modulate internal calcium homeostasis. CD4 was not present at the cell surface of purified astrocytes but CD4 mRNA could be detected by RT‐PCR. Neither HIV‐19533 (R5 isolate) nor HIV‐1LAI (X4 isolate) penetrated into purified astrocytes. In contrast, mixed CNS cell cultures were infected by HIV‐19533 and this was inhibited by anti‐CD4 mAb in 4/4 tested cultures and by anti‐CCR5 mAb in 2/4. Thus, the HIV‐1 R5 strain requires CD4 to penetrate into brain cells, suggesting that CCR5 cannot be used as the primary receptor for M‐tropic HIV‐1 strains in astrocytes. Moreover, inconstant inhibition of HIV‐1 entry by anti‐CCR5 mAb supports the existence of alternative coreceptors for penetration of M‐tropic isolates into brain cells. GLIA 34:165–177, 2001. © 2001 Wiley‐Liss, Inc.