bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective portal clamping to minimize hepatic ischaemia–reperfusion damage and avoid accelerated outgrowth of experimental colorectal liver metastases
Authors: van der Bilt J D W , Kranenburg O , Verheem A , van Hillegersberg R , Borel Rinkes I H M
Published: May 2006

Background

Temporary vascular clamping during local ablation for colorectal liver metastases increases destruction volumes. However, it also causes ischaemia–reperfusion (IR) injury to the liver parenchyma and accelerates the outgrowth of microscopic tumour deposits. The aim of this study was to investigate the effects of selective portal clamping on hepatocellular damage and tumour growth.

Methods

Mice carrying pre-established hepatic colorectal micrometastases underwent either simultaneous clamping of both the portal vein and the hepatic artery or selective clamping of the portal vein to the median and left liver lobes for 45 min. Sham-operated mice served as controls. Hepatic injury and tumour growth were assessed over time.

Results

Standard inflow occlusion resulted in a rise in liver enzymes, a local inflammatory response and hepatocellular necrosis. The outgrowth of pre-established micrometastases was accelerated three- to fourfold in clamped compared with non-clamped liver lobes (27·4 versus 7·8 per cent, P < 0·010). Conversely, selective portal clamping induced minimal liver injury, tissue inflammation or hepatocellular necrosis, and completely stopped the accelerated outgrowth of micrometastases.

Conclusion

Selective portal clamping does not induce liver tissue damage or accelerate micrometastasis outgrowth and may therefore be the preferable clamping method during local ablative treatment of hepatic metastases.
Clinical outcome of high segmental gastrectomy for early gastric cancer in the upper third of the stomach
Authors: Shinohara T , Ohyama S , Muto T , Kato Y , Yanaga K , Yamaguchi T
Published: May 2006

Background

Reflux oesophagitis is commonly encountered in the surgical treatment of cancer of the upper third of the stomach. The aim of this study was to describe a novel surgical technique and evaluate the clinical outcome of high segmental gastrectomy for early-stage proximal gastric cancer.

Methods

Thirty consecutive patients with early gastric cancer located in the upper third of the stomach were included, of whom 12 underwent high segmental gastrectomy and 18 underwent proximal gastrectomy with jejunal interposition. The incidence of reflux oesophagitis and nutritional parameters were compared between the two groups at 1 year after operation.

Results

One patient had mild reflux symptoms and two had endoscopic evidence of oesophagitis 1 year after high segmental gastrectomy. Half of the patients who had proximal gastrectomy had reflux symptoms of varying severity and 14 had endoscopic evidence of oesophageal changes at 1 year after surgery. There were significant differences between groups in the incidence of reflux symptoms (P = 0·016) and endoscopically detected gastro-oesophagitis (P < 0·001). There were no adverse events in either group, and the survival rate after high segmental gastrectomy appeared favourable.

Conclusion

Selected patients with early-stage proximal gastric cancer benefit from high segmental gastrectomy in terms of reduced reflex oesophagitis, without jeopardizing curability.
Increased diagnostic yield of small bowel tumors with capsule endoscopy
Authors: Cobrin Gena M. , Pittman Robert H. , Lewis Blair S.
Published: May 2006

BACKGROUND

It is believed that cancers of the small intestine represent <2% of all malignant tumors of the gastrointestinal tract, although the accuracy of this estimate is unknown, because the current methodologies for examining the small bowel have proved inadequate. Capsule endoscopy allows a more detailed inspection of the small intestine and may improve the ability to diagnose small bowel tumors. The objective of this study was to evaluate the effectiveness of capsule endoscopy in diagnosing small bowel tumors and to help establish the true incidence of tumors in obscure gastrointestinal bleeding.

METHODS

A retrospective analysis of the charts of 562 patients who underwent capsule endoscopy from August 2001 to November 2003 for a variety of indications was performed. The indication for the procedure was bleeding (alone or in addition to another indication, such as abnormal imaging) in 443 patients.

RESULTS

A diagnosis was made by capsule endoscopy in 277 patients (49.3%). Of 562 patients who were included in the study, 50 patients (8.9%) were diagnosed with small bowel tumors. The types of tumor diagnosed by capsule endoscopy included 8 adenocarcinomas (1.4%), 10 carcinoids (1.8%), 4 gastrointestinal stromal tumors (0.7%), 5 lymphomas (0.9%), 3 inflammatory polyps, 1 lymphangioma, 1 lymphangioectasia,1 hemangioma, 1 hamartoma, and 1 tubular adenoma. Of the tumors diagnosed, 48% were malignant. It was observed that 9 of 67 patients (13%) younger than age 50 years who underwent capsule endoscopy for obscure bleeding had small bowel tumors. The pathology results were not available for 10 patients.

CONCLUSIONS

Capsule endoscopy diagnosed small bowel tumors in 8.9% of patients who underwent the procedure for a variety of reasons, establishing it as an effective diagnostic modality. This incidence of small bowel tumors suggests an important role for capsule endoscopy in the algorithm for the diagnostic work‐up of patients with suspected small bowel lesions. Capsule endoscopy may lead to earlier detection and treatment of small bowel tumors and an improved prognosis for patients with these neoplasms. Cancer 2006. © 2006 American Cancer Society.
Distinct subpopulations of cyclic guanosine monophosphate (cGMP) and neuronal nitric oxide synthase (nNOS) containing sympathetic preganglionic neurons in spontaneously hypertensive and Wistar‐Kyoto rats
Authors: Powers‐Martin Kellysan , McKitrick Douglas J. , Arnolda Leonard F. , Phillips Jacqueline K.
Published: May 2006

The sympathetic preganglionic neurons (SPN) of the intermediolateral cell column (IML) play a critical role in the maintenance of vascular tone. We undertook a comparative neuroanatomical analysis of neuronal nitric oxide synthase (nNOS) expression in the SPN of the mature normotensive Wistar Kyoto (WKY) and spontaneously hypertensive rat (SHR). The anatomical relationship between nNOS and the NO signaling molecule cyclic guanosine monophosphate (cGMP) was also determined. All animals were male, age >6 months. Fluorogold (FG) retrograde labeling of SPN (detected with immunohistochemistry) was combined with NADPH‐diaphorase histochemistry for NOS in the thoracic spinal cord (T1–11, n = 5 WKY, 5 SHR). There was no difference in the total number of FG‐labeled SPN (WKY 6,542 ± 828, SHR 6,091 ± 820), but the proportion of FG‐labeled cells expressing NOS was significantly less in the SHR (WKY 64.4 ± 5.1 vs. SHR 55.6 ± 2.1,P< 0.05). Fluorescence immunohistochemistry for nNOS/cGMP (n = 4 WKY, 4 SHR) was also performed. Confocal microscopy revealed that all nNOS‐positive SPN contain cGMP and confirmed a strain‐specific anatomical arrangement of SPN cell clusters. A novel subpopulation of cGMP‐only cells were also identified. Double labeling for cGMP and choline acetyltransferase (n = 3 WKY, 3 SHR), confirmed these cells as SPN in both WKY and SHR. These results suggest that cGMP is a key signaling molecule in SPN, and that a reduced number of NOS neurons in the SHR may play a role in the increase in sympathetic tone associated with hypertension in these animals. J. Comp. Neurol. 497:566–574, 2006. © 2006 Wiley‐Liss, Inc.
Osteoblast‐like cell attachment to and calcification of novel phosphonate‐containing polymeric substrates
Authors: Gemeinhart Richard A. , Bare Christopher M. , Haasch Richard T. , Gemeinhart Ernest J.
Published: May 2006

In an attempt to interact natural bone and bone cells with biomaterials and to begin to develop modular tissue engineering scaffolds, substrates containing phosphonate groups were identified to mimic mineral–protein and natural polymer–protein interactions. In this study, we investigated poly(vinyl phosphonic acid) copolymer integration with existing materials as a graft‐copolymer surface modification. Phosphonate‐containing copolymer‐modified surfaces were created and shown to have varying phosphate content within different polymeric surfaces. As the phosphonate content in the monomer feed approached 30% vinyl phosphonic acid, increased osteoblast‐like cell adhesion (3‐ to 8‐fold increase in adhesion) and proliferation (2‐ to10‐fold increase in proliferation rate) was observed. Since surfaces modified with 30% vinyl phosphonic acid in the feed exhibited a maximal cell adhesion and proliferation (9.4 × 104 cells/cm2/day), it was hypothesized that this copolymer composition was optimal for protein–polymer interactions. Osteoblast‐like cells formed confluent layers and were able to differentiate on all surfaces that contained vinyl phosphonic acid. Most importantly, cells interacting with these surfaces were able to significantly mineralize the surface. These results suggest that phosphonate‐containing polymers can be used to integrate biomaterials with natural bone and could be used for tissue engineering applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Crystallochemistry, textural properties, and in vitro biocompatibility of different silicon‐doped calcium phosphates
Authors: Arcos D. , Sánchez‐Salcedo S. , Izquierdo‐Barba I. , Ruiz L. , González‐Calbet J. , Vallet‐Regí M.
Published: May 2006

Three silicon‐doped calcium phosphates (Si‐CaPs) were synthesized by heating precipitated silicon‐doped apatite via different thermal treatments. Temperatures of 700°C, 900°C, and 1100°C led to an apatite‐glass biphasic material, nanocrystalline Si‐doped apatite (SiHA), and Si‐doped apatite‐α tricalcium phosphate biphasic material, respectively. Structure, microstructure, textural properties, and chemical differences were determined for the three bioceramics. Biocompatibility tests were carried out by seeding osteblast‐like cells onto the three substrates. Si‐CaP treated at 700°C and 900°C led to Ca decrease in the culture media, partially impeding the cell proliferation over them. However, the proliferation capability is restored when additional culture medium is added. Finally, cytotoxicity results indicated that cell damage is much lower in osteblast‐like cells seeded onto SiHA and SiHA‐α tricalcium phosphate samples than in plastic culture control. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Influence of poly(ethylene glycol)‐α‐cyclodextrin complexes on stabilization and transdermal permeation of ascorbic acid
Authors: Davaran Soodabeh , Hanaee Jalal , Rashidi Mohammad R. , Valiolah Fatemeh , Hashemi Mahdi
Published: May 2006

The present study was conducted to investigate the effect of poly(ethylene glycol)‐α‐cyclodextrin (α‐CD) complexes on stabilization and cutaneous permeation of ascorbic acid from specially prepared transdermal patches. Poly(ethylene glycol) citrate (6‐armPEG) and its inclusion complex with α‐CD were prepared and used for preparation of the transdermal patches. Duro‐Tak 87–2979 was taken as an adhesive matrix in combination with ascorbic acid. A diffusion cell with an artificial membrane was used to evaluate the absorption of ascorbic acid from the patches. The influence of drug release of α‐CD and two types of its PEG complexes (as the novel permeation enhancers) was tested. The 6‐armPEG‐α‐CD complex consisting of a PEG‐citric acid ester at a concentration of 0.08–0.1% (w/v) is a suitable stabilizer for ascorbic acid during UV assay. The release studies showed that the type of enhancer is important in diffusion of the drug across membrane. Furthermore, the diffusion of ascorbic acid was considerably enhanced in the presence of 6‐armPEG‐α‐CD complex. Inclusion complexes of 6‐armPEG with α‐CD at a concentration of 0.08–0.1% (w/v) is a suitable stabilizer for UV method of assay. The present data suggest that 6‐armPEG‐α‐CD complex is also useful in enhancing the release of ascorbic acid from the acrylic type pressure sensitive adhesives. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Butylated hydroxyanisole regulates ARE‐mediated gene expression via Nrf2 coupled with ERK and JNK signaling pathway in HepG2 cells
Authors: Yuan Xiaoling , Xu Changjiang , Pan Zui , Keum Young‐Sam , Kim Jung‐Hwan , Shen Guoxiang , Yu Siwang , Oo Khor Tin , Ma Jianjie , Kong Ah‐Ng Tony
Published: May 2006

Many natural and synthetic cancer chemopreventive compounds are potent inducers of phase II detoxifying and antioxidant stress responsive genes. The phase II/antioxidant gene expression plays critical role in chemoprevention of carcinogenesis. The antioxidant responsive element (ARE), located on many phase II/antioxidant genes, binds with the transcription factor Nrf2, and is required for the activation of these phase II/antioxidant gene expression induced by many natural and synthetic cancer chemopreventive compounds. In this study, we investigated the potential roles of extracellular signal‐regulated kinase (ERK) and c‐jun N‐terminal kinase (JNK) in the regulation of butylated hydroxyanisole (BHA)‐induced and Nrf2‐dependent ARE transcriptional activity and ARE‐mediated endogenous heme oxygenase‐1 (HO‐1) protein expression in HepG2 cells. ARE transcriptional activity and HO‐1 protein expression were increased dose dependently after treatment with BHA in HepG2 cells. Dose‐response and time‐course experiments showed that BHA increased the accumulation of Nrf2, and concomitantly decreased the protein level of Keap1. We next examined the phosphorylation of the MAPKs, and found that BHA significantly increased the phosphorylation levels of ERK1/2 and JNK1/2. Importantly BHA‐induced ARE transcriptional activity was attenuated by the inhibition of ERK and JNK signaling using biochemical inhibitors and their dominant‐negative mutants. Using confocal microscopy technique, treatment with BHA showed the release of Nrf2 sequestered by Keap1 in the cytosol, and that Nrf2 translocated into the nucleus. Importantly, cDNA transfections of ERK and JNK signaling pathways similarly released Nrf2 from Keap1 cytosolic sequestration and translocating Nrf2 into the nucleus. Taken together, these results strongly suggested that ERK and JNK signaling pathways played important and positive roles in BHA‐induced and Nrf2‐dependent regulation of ARE‐mediated gene expression, as well as the nuclear translocation of Nrf2 in HepG2 cells. © 2006 Wiley‐Liss, Inc.
Review of existing and newly developed approaches to obtain timber embedding strength
Authors: Zhou Tinozivashe , Guan Zhongwei
Published: May 2006

Embedding strength is a key parameter most commonly adopted for designing laterally loaded timber joints fastened with dowel‐type fasteners. This property, however, is non‐unique for any given specimen of timber but is dependent upon several factors. Currently, there is a scarcity of literature that considers some of the major factors as a whole. In this review, an attempt is made to bring some of these factors together and then examine them in the context of historical test results. This is followed by new test results derived from idealized tests for application in designing double‐sided punched metal plate fastened joints. It is shown that changes in combinations of factors can potentially lead to appreciable differences in the values of embedding strength obtained from tests. By accounting for the quantitative effect of some key factors, it is possible to explain differences between theoretically obtained embedding strength values and idealized test results. In addition, the proposed indirect method of obtaining effective embedding strengths for punched metal plate timber joints is validated through correlation of idealized test results with theoretical calculations.
Rechtsseitige Unterbauchschmerzen mit atypischem Befund
Authors: Maier  , Kettelhack  , Adams  , Bongartz  , Sonnet
Published: May 2006

Ein 57-jähriger Patient wurde bei akuten rechtsseitigen Unterbauchschmerzen mit der Verdachtsdiagnose einer akuten Appendizitis hospitalisiert. Im präoperativen Ultraschall zeigte sich im rechten Unterbauch ein atypischer Befund mit einer zystischen Raumforderung mit Sedimentationszeichen. Laparoskopisch zeigte sich eine rupturierte Mukozele mit Schleimauflagerung auf dem Peritoneum. Es wurde eine Ileozökalresektion durchgeführt. Histopathologisch wurde ein infiltrierendes muzinöses Zystadenokarzinom nachgewiesen. Der Patient erhält eine adjuvante intraperitoneale Chemotherapie. Trotz klassischer klinischer Zeichen einer akuten Appendizitis sollte bei atypischem sonographischem Befund einer zystischen Masse im rechten Unterbauch an die Verdachtsdiagnose einer Mukozele mit möglicherweise zugrunde liegendem Malignom gedacht werden.
Ein Kleinkind mit akutem Abdomen und Eisenmangelanämie
Authors: Schlapbach  , Liniger  , Schibli  , Cholewa
Published: May 2006

Über ein 20 Monate altes Mädchen wird berichtet, das wegen Verschlechterung des Allgemeinzustandes im Rahmen einer unblutigen Gastroenteritis zugewiesen wurde. Im Eintrittsstatus fanden sich Zeichen eines akuten Abdomens mit schwerer Dehydratation. Die Laboruntersuchungen belegten erhöhte Infektparameter sowie eine schwere hypochrome, mikrozytäre Anämie ohne Hämolyse, das Abdomenröntgenbild zeigte einen diffusen Meteorismus. Das Kind wurde laparoskopiert. Intraoperativ fand sich ein perforiertes Meckel-Divertikel. Meckel-Divertikel manifestieren sich typischerweise mit akuter unterer gastrointestinaler Blutung oder intestinaler Obstruktion; Darmperforation und chronische Anämie sind seltene Komplikationen. Die Differentialdiagnosen beim Kind mit akutem Abdomen sowie die Klinik des Meckel-Divertikels werden diskutiert.
Lebensqualität älterer pflegender Angehöriger von Demenzkranken
Authors: Winkler Ines , Kilian Reinhold , Matschinger Herbert , Angermeyer Matthias C.
Published: May 2006

Zusammenfassung: Im Rahmen des WHOQOL-OLD-Projektes wurde die Lebensqualität (LQ) sowohl von älteren pflegenden Angehörigen Demenzkranker als auch von nichtpflegenden älteren Menschen (60 Jahre und älter) mit Hilfe des WHOQOL-BREF und WHOQOL-OLD erfasst. Außerdem wurden Komorbidität sowie bei den Pflegenden zusätzliche Informationen zur Pflege erhoben. Es zeigten sich deutliche Unterschiede hinsichtlich der LQ. So bewerteten die pflegenden Angehörigen ihre LQ signifikant schlechter als Personen ihres Alters, die keinen Angehörigen pflegen. Diese deutlich schlechtere Bewertung ihrer LQ kann hauptsächlich auf die im Rahmen der Pflege entstehende Belastung zurückgeführt werden.
Lebensqualität im Alter vor dem Hintergrund knapper Ressourcen im Gesundheitswesen
Authors: Esslinger A.S. , Heppner H.J.
Published: May 2006

Zusammenfassung: Der Erhalt einer möglichst dauerhaft hohen Lebensqualität im Alter ist Ausdruck erfolgreichen Alterns. Der Faktor Gesundheit spielt hierbei eine wesentliche, wenn nicht gar die bedeutendste, Rolle. Um die Gesundheit über die gesamte Lebensspanne aufrecht halten zu können, müssen Maßnahmen im Rahmen der Gesundheitsversorgung erfolgen. Dies bedarf finanzieller Aufwendungen. Da das Gesundheitswesen unter Kostendruck steht, finden Ressourcenallokationen statt. In diesem Zusammenhang ist auch die Altersrationierung zu sehen. Sie tritt in expliziter und impliziter Form auf. Es gilt, aus unterschiedlichen Blickwinkeln heraus zu diskutieren, ob und inwieweit eine solche Rationierung angemessen ist und zur Lösung der Kostenproblematik beiträgt.
Global models of surface wave attenuation
Authors: Dalton Colleen A. , Ekström Göran
Published: May 2006

A large data set of fundamental mode Rayleigh wave amplitudes is analyzed to derive global models of surface wave attenuation (1/Q). The data set consists of measurements of Rayleigh wave amplitude anomalies in the period range 50–250 s for 347 earthquakes observed at 179 seismic stations. The amplitude anomalies are considered to depend on four factors: intrinsic attenuation along the ray path, elastic focusing effects along the ray path, a source factor accounting for uncertainties in the strength of excitation, and a receiver factor accounting for uncertainties in the response at the station. The amplitude data are inverted simultaneously for global maps of attenuation expanded in spherical harmonics up to degree 12, global maps of phase velocity expanded to degree 20, and source and receiver correction factors. All four variable types are shown to be important in explaining the amplitude anomalies. A data set of phase delay measurements provides additional constraints on velocity structure. The maps of attenuation obtained by simultaneous inversion for elastic and anelastic models contain important features that are not robustly imaged when the effect of focusing on wave amplitude is ignored. These include high attenuation along western North America and along the East Pacific Rise and other ridge systems and low attenuation associated with stable continental interiors. The global attenuation maps exhibit a strong correlation with phase velocity maps corrected for the effect of the crust, particularly for periods <200 s. The correlation suggests that the variability in both Q and velocity in the shallow upper mantle is primarily thermal in origin.
GPS constraints on continental deformation in the Africa‐Arabia‐Eurasia continental collision zone and implications for the dynamics of plate interactions
Authors: Reilinger Robert , McClusky Simon , Vernant Philippe , Lawrence Shawn , Ergintav Semih , Cakmak Rahsan , Ozener Haluk , Kadirov Fakhraddin , Guliev Ibrahim , Stepanyan Ruben , Nadariya Merab , Hahubia Galaktion , Mahmoud Salah , Sakr K. , ArRajehi Abdullah , Paradissis Demitris , Al‐Aydrus A. , Prilepin Mikhail , Guseva Tamara , Evren Emre , Dmitrotsa Andriy , Filikov S. V. , Gomez Francisco , Al‐Ghazzi Riad , Karam Gebran
Published: May 2006

The GPS‐derived velocity field (1988–2005) for the zone of interaction of the Arabian, African (Nubian, Somalian), and Eurasian plates indicates counterclockwise rotation of a broad area of the Earth's surface including the Arabian plate, adjacent parts of the Zagros and central Iran, Turkey, and the Aegean/Peloponnesus relative to Eurasia at rates in the range of 20–30 mm/yr. This relatively rapid motion occurs within the framework of the slow‐moving (∼5 mm/yr relative motions) Eurasian, Nubian, and Somalian plates. The circulatory pattern of motion increases in rate toward the Hellenic trench system. We develop an elastic block model to constrain present‐day plate motions (relative Euler vectors), regional deformation within the interplate zone, and slip rates for major faults. Substantial areas of continental lithosphere within the region of plate interaction show coherent motion with internal deformations below ∼1–2 mm/yr, including central and eastern Anatolia (Turkey), the southwestern Aegean/Peloponnesus, the Lesser Caucasus, and Central Iran. Geodetic slip rates for major block‐bounding structures are mostly comparable to geologic rates estimated for the most recent geological period (∼3–5 Myr). We find that the convergence of Arabia with Eurasia is accommodated in large part by lateral transport within the interior part of the collision zone and lithospheric shortening along the Caucasus and Zagros mountain belts around the periphery of the collision zone. In addition, we find that the principal boundary between the westerly moving Anatolian plate and Arabia (East Anatolian fault) is presently characterized by pure left‐lateral strike slip with no fault‐normal convergence. This implies that “extrusion” is not presently inducing westward motion of Anatolia. On the basis of the observed kinematics, we hypothesize that deformation in the Africa‐Arabia‐Eurasia collision zone is driven in large part by rollback of the subducting African lithosphere beneath the Hellenic and Cyprus trenches aided by slab pull on the southeastern side of the subducting Arabian plate along the Makran subduction zone. We further suggest that the separation of Arabia from Africa is a response to plate motions induced by active subduction.
Height and seasonal dependence of aerosol optical properties over southeast Italy
Authors: De Tomasi F. , Tafuro A. M. , Perrone M. R.
Published: May 2006

Systematic Raman lidar measurements performed from May 2000 to August 2002 in the framework of the European Aerosol Research Lidar Network are analyzed and discussed. Main results on height dependence and seasonal cycle of extinction α(z) and backscatter β(z) coefficients, aerosol optical depths AOD(z), and lidar ratios S(z) are presented. Yearly‐averaged vertical profiles of extinction and backscatter coefficients reveal that both α(z) and β(z) decrease more than 75% within the lowermost 2 km. Yearly‐averaged lidar ratios increase from about 42–48 sr in the lowermost 2 km to between 67–72 sr in the air masses above 2 km. The changes in lidar ratios are indicative of changes in the physical characteristics of the monitored aerosols and suggest that over the monitoring site, the lowermost air masses (z < 2 km) are on average characterized by a larger concentration of particles leading to S values typical of marine aerosols, while the elevated air masses (z > 2 km) are characterized by lidar ratios typical of continental aerosol type. The seasonal cycle analysis reveals that the average maximum height zM at which aerosols are detected by the lidar that is about 5 km in spring‐summer, and decreases up to about 3 km in autumn‐winter. Monthly AODs span the 0.16–0.26 range in autumn‐winter and the 0.26–0.4 range in spring‐summer. The scarce renovation of air masses, occurring in spring‐summer as a consequence of the weather stability, favours the accumulation of the atmospheric aerosol particles and may account for the larger AODs and zM values.
Three-dimensional horizontal circular spiral photonic crystals with stop gaps below 1μm
Authors: Seet Kock Khuen , Mizeikis Vygantas , Juodkazis Saulius , Misawa Hiroaki
Published: May 2006

Three-dimensional photonic crystals with a circular spiral architecture were fabricated by direct laser writing (DLW) in a photoresist. DLW was performed with a laser beam having the direction of propagation and elongation of the ellipsoidal focal region perpendicular to the spirals’ orientation. This allowed the reduction of the turning period of the spirals while avoiding the overlap between their adjacent turns. Consequently, optical transmission and reflection spectra of the fabricated samples revealed multiple photonic stop gaps whose shortest wavelength was 0.88μm, the lowest observed so far in spiral structures. These results were qualitatively reproduced by finite-difference time-domain simulations. This fabrication scheme can be useful for DLW of structures where photonic stop gaps along particular directions, rather than complete photonic band gaps, are required.
Demonstration of optical microfiber knot resonators
Authors: Jiang Xiaoshun , Tong Limin , Vienne Guillaume , Guo Xin , Tsao Albert , Yang Qing , Yang Deren
Published: May 2006

We demonstrate optical resonance from microfiber knots obtained by manipulating freestanding silica microfibers. Q factors as high as 57 000 with finesse of 22 are observed in knots with sizes less than 1mm. The free spectral range of the resonator can be easily tuned by tightening the knot structure in air. The knot resonators are highly stable in water with Q factors up to 31 000 and finesse of 13. The possibility of supporting the knot resonator with a solid MgF2 substrate is also demonstrated.
Photothermal operation of high frequency nanoelectromechanical systems
Authors: Sampathkumar A. , Murray T. W. , Ekinci K. L.
Published: May 2006

We describe photothermal operation of nanoelectromechanical systems (NEMS) in ambient atmosphere. Using a tightly focused modulated laser source, we have actuated the out-of-plane flexural resonances of bilayered doubly clamped beams. The optically detected displacement profiles in these beams are consistent with a model where the absorbed laser power results in a local temperature rise and a subsequent thermally induced bending moment. The described technique allows probing and actuation of NEMS with exquisite spatial and temporal resolution. From a device perspective, the technique offers immense frequency tunability and may enable future NEMS that can be remotely accessed without electronic coupling.
Relationships between prescribed burning and wildfire occurrence and intensity in pine - hardwood forests in north Mississippi, USA
Authors: Brewer Stephen , Rogers Corey
Published: May 2006

Using Geographic Information Systems and US Forest Service data, we examined relationships between prescribed burning (from 1979 to 2000) and the incidence, size, and intensity of wildfires (from 1995 to 2000) in a landscape containing formerly fire-suppressed, closed-canopy hardwood and pine–hardwood forests. Results of hazard (failure) analyses did not show an increased likelihood of large, small, or intense wildfires with an increase in the number of years since the last prescribed fire. Wildfires of various sizes and intensities were more likely to occur in years with lower than average precipitation, regardless of when these areas were last burned. Calculations of expected lightning-fire potential based on weather patterns predicted a peak in lightning-started fires in the early to late summer. Lightning fires were rare, however, and wildfire activity was greatest in the spring and fall. We hypothesize that the ineffectiveness of prescribed burning in reducing wildfire hazard and the low incidence of wildfires in the midsummer in north Mississippi are both artifacts of fire suppression in the past, which converted open oak–pine woodlands with persistent pyrogenic surface fuels that accumulated over time to closed-canopy forests that lack such fuels. We suggest that open canopies and grass-based surface fuels must first be restored before prescribed burning will achieve most desirable management goals in this region, including hazard reduction and ecological restoration of natural fire regimes.
Multiple and time-scheduled
in situ
DNA delivery mediated by β-cyclodextrin embedded in a polyelectrolyte multilayer
Authors: Jessel N. , Oulad-Abdelghani M. , Meyer F. , Lavalle P. , Haîkel Y. , Schaaf P. , Voegel J.-C.
Published: May 2006

The basic premise of gene therapy is that genes can be used to produce
in situ
therapeutic proteins. The controlled delivery of DNA complexes from biomaterials offers the potential to enhance gene transfer by maintaining an elevated concentration of DNA within the cellular microenvironment. Immobilization of the DNA to the substrate to which cells adhere maintains the DNA in the cell microenvironment for subsequent cellular internalization. Here, layer-by-layer (LBL) films made from poly(
l
-glutamic acid) (PLGA) and poly(
l
-lysine) (PLL) containing DNA were built in the presence of charged cyclodextrins. The biological activities of these polyelectrolyte films were tested by means of induced production of a specific protein in the nucleus or in the cytoplasm by cells in contact with the films. This type of coating offers the possibility for either simultaneous or sequential interfacial delivery of different DNA molecules aimed at cell transfection. These results open the route to numerous potential applications in patch vaccination, for example.
Precraniate origin of cranial motoneurons
Authors: Dufour Héloïse D. , Chettouh Zoubida , Deyts Carole , de Rosa Renaud , Goridis Christo , Joly Jean-Stéphane , Brunet Jean-François
Published: May 2006

The craniate head is innervated by cranial sensory and motor neurons. Cranial sensory neurons stem from the neurogenic placodes and neural crest and are seen as evolutionary innovations crucial in fulfilling the feeding and respiratory needs of the craniate “new head.” In contrast, cranial motoneurons that are located in the hindbrain and motorize the head have an unclear phylogenetic status. Here we show that these motoneurons are in fact homologous to the motoneurons of the sessile postmetamorphic form of ascidians. The motoneurons of adult
Ciona intestinalis
, located in the cerebral ganglion and innervating muscles associated with the huge “branchial basket,” express the transcription factors CiPhox2 and CiTbx20, whose vertebrate orthologues collectively define cranial motoneurons of the branchiovisceral class. Moreover,
Ciona
's postmetamorphic motoneurons arise from a hindbrain set aside during larval life and defined as such by its position (caudal to the prosensephalic sensory vesicle) and coexpression of
CiPhox2
and
CiHox1
, whose orthologues collectively mark the vertebrate hindbrain. These data unveil that the postmetamorphic ascidian brain, assumed to be a derived feature, in fact corresponds to the vertebrate hindbrain and push back the evolutionary origin of cranial nerves to before the origin of craniates.
MATERNAL AND EMBRYONIC CONTRIBUTIONS TO THE FUNCTIONAL MESSENGER RNA OF EARLY DEVELOPMENT
Authors: Crippa Marco , Gross Paul R.
Published: May 2006

Some of the DNA-like RNA synthesized during oögenesis remains available up to early blastula (stage 7). This RNA then begins to disappear from the embryo, so that by early gastrulation half of its sequences have been lost. Total maternal RNA of embryos represents more sequences than can be recovered at early stages from polyribosomes. Some of it must therefore reside in cytoplasmic fractions that do not cosediment with polyribosomes. Most of the maternal DNA-like RNA is eventually translated before it is lost. Messenger RNA transcribed on the embryonic genomes appears very early on polyribosomes and is translated there along with maternal RNA.
CHROMOSOMAL RECEPTOR FOR A VITAMIN D METABOLITE
Authors: Haussler Mark R. , Norman Anthony W.
Published: May 2006

Evidence has been presented for the existence of an acidic protein(s) or protein portion of a more complex molecule which has a high affinity for binding noncovalently a biologically active metabolite of vitamin D. This molecule could be solubilized from the residual chromatin via treatment with either 0.3
M
KCl or high pH and has been purified 167-fold over the crude mucosa homogenate. Characterization of the still crude receptor fraction showed that it contains significant amounts of RNA and that it may exist in multiple forms, i.e., a 50,000-70,000 and a >200,000 molecular weight species. The binding capacity of the receptor fraction for the metabolite is saturated after administration of a physiological dose of the parent vitamin D.
SYNTHESIS AND INDUCTION OF TYROSINE AMINOTRANSFERASE IN SYNCHRONIZED HEPATOMA CELLS IN CULTURE
Authors: Martin David , Tomkins Gordon M. , Granner Daryl
Published: May 2006

The generation cycle of an established line of rat hepatoma cells (HTC cells) was studied using synchronized cell techniques. Dexamethasone phosphate (Dex), a synthetic adrenal corticosteriod which induces tyrosine aminotransferase (TAT) in HTC cells randomly distributed in the cell generation cycle, did not affect the durations of the various phases of the cycle. The activities of TAT and several dehydrogenases, and the rates of general protein and RNA synthesis, were studied throughout the cycle.

Dex, at 10
-5
M
, when added to a synchronized cell population in the latter two thirds of G1 phase or anywhere in the S phase, induces TAT. During the period made up of G2, M, and early G1, Dex does not induce TAT. However, radioisotope incorporation into specifically immunoprecipitated TAT continues during mitosis, when general protein and RNA synthesis are decreased.
A NEW CHROOCOCCACEAN ALGA FROM THE PROTEROZOIC OF QUEENSLAND
Authors: Licari Gerald R. , Cloud Preston E. , Smith W. D.
Published: May 2006

Nannofossils§ here described are from the middle Proterozoic Paradise Creek Formation, along Paradise Creek in northwestern Queensland, Australia. These fossils, in chert blebs associated with branched stromatolites, comprise cubic colonies analogous to living
Eucapsis
, a member of the blue-green algal family Chroococcaceae. The age of the enclosing rocks, bracketed by the ages of older and younger granitic events, is about 1.6 × 10
9
years. We record, therefore, a new chronological and biological datum in the currently accumulating sequence of pre-Paleozoic microbiotas.
LINKAGE AND SELECTION: NEW EQUILIBRIUM PROPERTIES OF THE TWO-LOCUS SYMMETRIC VIABILITY MODEL
Authors: Karlin Samuel , Feldman Marcus W.
Published: May 2006

In the two-locus symmetric viability model with recombination, conditions for the existence and stability of a new class of polymorphic equilibria are given. These „unsymmetric” equilibria, which exist for relatively loose linkage, can be explicitly obtained, in contrast to the previously known symmetric equilibria which are generally given by the solutions of a cubic equation.

For sufficiently tight linkage, there is always at least one stable symmetric equilibrium. Seven is the precise maximum for the number of interior equilibria. The qualitative consequences of these results are briefly examined. In particular it is pointed out that since for some linkage values no stable polymorphic equilibria exist, there is no „overdominance theorem” comparable to the single-locus case.
FEEDBACK INHIBITION OF THE DEVELOPMENT OF MACROPHAGE AND GRANULOCYTE COLONIES, II. INHIBITION BY GRANULOCYTES
Authors: Paran Michael , Ichikawa Yasuo , Sachs Leo
Published: May 2006

It has been shown that mature normal rat granulocytes produce a substance that inhibits the activity of the inducer required for the development of macrophages (M) and granulocyte (G) colonies from normal hematopoietic cells seeded in soft agar. The granulocyte inhibitor inhibited the activity of the inducer when tested with normal hematopoietic cells from embryonic or adult organs. The inhibitor was not dialyzable, and was obtained in an active form in granulocyte-conditioned medium. The results indicate that the control mechanism that regulates the growth and development of normal macrophages and granulocytes includes a feedback inhibition of the activity of the inducer by inhibitors produced by mature granulocytes and macrophages, presumably at the end of their differentiation process. The inhibition of both M and G colonies by the feedback inhibitors produced by macrophages and granulocytes suggests that both types of colonies may be derived from a common stem cell. A line of primitive myeloid leukemia did not inhibit the activity of the inducer, and the cells of this line were not inhibited by the feedback inhibitors produced by normal granulocytes and macrophages.
RESONANCE STABILIZATION OF CYCLE GROUPS OF HYDROGEN-BONDED WATER MOLECULES
Authors: Bass G. E.
Published: May 2006

A quantum-mechanical resonance effect can be associated with cyclic groups of hydrogen-bonded water molecules and, conceivably, might influence the structure of liquid water (M. Ageno, these PROCEEDINGS, 57, 567 (1967)). However, from the calculations presented here, this resonance stabilization appears to be too small (<0.1 kcal/mole) to over come the thermal motion of the water molecules and consequently cannot significantly influence the liquid water structure. The model developed here permits the estimation of an upper limit to the stabilization. The bridge protons are imagined to be simultaneously tunneling through the barriers of equivalent symmetric double-well potentials, and the resulting energy-level splittings are related to the resonance stabilization.
STUDIES ON THE DISTRIBUTION AND PROPERTIES OF A NEW CLASS OF CELL DIVISION-PROMOTING SUBSTANCES FROM HIGHER PLANT SPECIES
Authors: Wood Henry N. , Braun Armin C. , Brandes Hans , Kende Hans
Published: May 2006

One member of a new class of cell division-promoting substances, which are nicotinamide derivatives, has been found to be present in dividing cells of tobacco and cactus. These plants are taxonomically far removed from one another and from
Vinca rosea
L., the plant species from which the new substances were first isolated. Because of their apparent wide distribution among dicotyledonous plant species, the question is raised as to whether the nicotinamide derivatives rather than the purine cytokinins may not, in fact, be the naturally occurring cell division factors that are directly involved in promoting cytokinesis in higher plant species. Unequivocal evidence is presented to show that the nicotinamide derivatives do not owe their biological activity to contamination by 6-substituted purine cytokinins.
SERUM-MEDIATED PROTECTION OF NEOPLASTIC CELLS FROM INHIBITION BY LYMPHOCYTES IMMUNE TO THEIR TUMOR-SPECIFIC ANTIGENS
Authors: Hellström Ingegerd , Hellström Karl Erik , Evans Charles A. , Heppner Gloria H. , Pierce George E. , Yang James P. S.
Published: May 2006

The combined effect of immune lymphocytes (lymphnode cells or blood lymphocytes) and serum from tumor-bearing donors was assessed in four tumor systems with the use of the colony inhibition assay: (
a
) Moloney virus-induced sarcomas in mice, (
b
) Shope papillomas in rabbits, (
c
) spontaneous mammary carcinomas in mice, and (
d
) two adenocarcinomas of the colon and two adenocarcinomas of the lung in humans. The neoplasms studied had previously been shown to possess tumor-specific antigens, against which cellular immunity could be detected
in vitro
. In all four systems, it was found that sera from hosts with progressively growing neoplasms could abrogate the inhibitory effect of lymphocytes which were immune to the specific antigens of the corresponding tumor type. Studies with Moloney sarcomas, in particular, showed that the serum effect had at least some degree of specificity.
THE MOLECULAR ORIGIN OF LAMBDA PROPHAGE MRNA
Authors: Bear P. D. , Skalka A.
Published: May 2006

Lambda-specific RNA extracted from lysogenic bacteria hybridizes specifically with fragments of λ DNA containing 43 per cent GC (guanine plus cytosine). Therefore genes known to function in the prophage state (
c
I
and
rex
) lie 0.38 ± 0.08 fractional molecular length from the right end of the λ DNA molecule, according to the compositional map of Skalka, Burgi, and Hershey.
A SPECIFIC ANTI-PROINSULIN SERUM AND THE PRESENCE OF PROINSULIN IN CALF SERUM
Authors: Yip C. C. , Logothetopoulos J.
Published: May 2006

A specific antibody against proinsulin has been obtained by adsorbing the original anti-proinsulin guinea pig serum with a solid immunosorbent of Sephadex-insulin. The specificity of the antibody against antigenic determinants of proinsulin was established by radioimmunoassay and by passive cutaneous anaphylaxis (PCA) tests. The presence of proinsulin in calf serum has been demonstrated by (
a
) gel filtration of an acid alcohol extract of the serum followed by immunoassays of the fractions using anti-insulin or the specific anti-proinsulin serum, and (
b
) direct assay of calf serum with the specific anti-proinsulin serum.
THE ROLES OF SYNTHESIS AND DEGRADATION IN DETERMINING TISSUE CONCENTRATIONS OF LACTATE DEHYDROGENASE-5
Authors: Fritz Paul J. , Vesell Elliot S. , White E. Lucile , Pruitt Kenneth M.
Published: May 2006

C
14
-labeled amino acids were incorporated
in vivo
into LDH-5 of rat tissues. Different amounts of LDH-5 in liver, heart muscle, and skeletal muscle resulted from differences in rates of both intracellular degradation and synthesis. Rate constants for LDH-5 synthesis were 65, 2, and 5 picomoles per day per gram in rat liver, heart muscle, and skeletal muscle, respectively; rate constants for degradation were 0.041, 0.399, and 0.018 reciprocal days, respectively. The corresponding half-lives for LDH-5 in these tissues were 16, 1.6, and 31 days.

Markedly divergent rates of LDH-5 catabolism in various tissues suggest the possibility that one isozyme with a slow rate of destruction may serve to maintain critical enzymatic activity in a tissue where rapid degradation of another isozyme occurs.
STUDIES ON THE FORMATION OF TOBACCO MOSAIC VIRUS RIBONUCLEIC ACID, VIII. FATE OF PARENTAL VIRAL RNA IN THE HOST CELL
Authors: Reddi K. K.
Published: May 2006

Fate of parental viral RNA in the host cell was determined with the use of P
32
-labeled tobacco mosaic virus (TMV)-RNA as inoculum. There was a wide variation in the retention of TMV-RNA that was rubbed on the tobacco leaf surface. On the average, about 0.73 μg of viral RNA was retained by tobacco leaf. About 63 per cent of the retained RNA was degraded in the leaf cells. On the average, about 0.27 μg of TMV-RNA was conserved in a tobacco leaf.

The conserved parental TMV-RNA was remarkably stable and was located in the nuclear fraction of leaf homogenate. It could be isolated in an undegraded form and was RNase-sensitive, presumably single-stranded. About 2 per cent of it was associated with progeny TMV.
THE DIFFERENTIABILITY OF THE RIEMANN FUNCTION AT CERTAIN RATIONAL MULTIPLES OF π
Authors: Gerver Joseph
Published: May 2006

It is shown that a continuous function which Riemann is said to have believed to be nowhere differentiable is in fact differentiable at certain points.
SELECTIVE DESTRUCTION OF ADRENAL CORTEX BY PULSE DOSES OF DERIVATIVES OF 12-METHYLBENZ(a)ANTHRACENE
Authors: Huggins Charles , Morii Sotokichi , Pataki John
Published: May 2006

Pulse doses of emulsions of ten polynuclear aromatic hydrocarbons were found to destroy the adrenal cortex selectively.

The corticolytic hydrocarbons are derivatives of 12-methylbenz(a)anthracene which possess at position 7 an alkyl, methoxymethyl, formyl, or hydroxyalkyl group. It would appear that the active corticolytic agent is 7-hydroxyalkyl-12-methylbenz(a)anthracene, of chemical source or generated in metabolism.
RELEASE OF NEWLY SYNTHESIZED DOPAMINE FROM DOPAMINE-CONTAINING TERMINALS IN THE STRIATUM OF THE RAT
Authors: Besson M. J. , Cheramy A. , Feltz P. , Glowinski J.
Published: May 2006

The extraneuronal spontaneous efflux of
3
H-dopamine synthesized endogenously in dopamine terminals has been demonstrated
in vitro
, by collecting the
3
H amine in superfusates of isolated striatum of the rat previously incubated with
3
H-tyrosine. The
3
H-dopamine newly synthesized appears to be preferentially released. Furthermore, amphetamine and a monoamine oxidase inhibitor (Carton) markedly increased the release of
3
H-dopamine. This effect was also observed with substances normally contained in some striatal neurons: acetylcholine and 5-hydroxytryptamine.
D-AMINO ACID OXIDASE IN LEUKOCYTES: A POSSIBLE D-AMINO-ACID-LINKED ANTIMICROBIAL SYSTEM
Authors: Cline Martin J. , Lehrer Robert I.
Published: May 2006

D-Amino acid oxidase has been identified within the granule fraction of human neutrophilic leukocytes. Leukocyte homogenates and purified kidney D-amino acid oxidase can utilize either isolated D-amino acids or some species of bacteria as substrates for the generation of hydrogen peroxide. When linked to leukocyte myeloperoxidase
in vitro
, purified D-amino acid oxidase constitutes a system lethal for certain bacteria. It is proposed that leukocyte D-amino acid oxidase and myeloperoxidase constitute a biochemically specific system for the recognition and killing of certain microorganisms.
GENIC VARIATION IN A NATURAL POPULATION OF
Drosophila persimilis
Authors: Prakash Satya
Published: May 2006

The understanding of the speciation process can best be achieved by a knowledge of the genic differences between two closely related species and the correlation of such differences with the characteristics which demarcate the two species.
D. persimilis
and
D. pseudoobscura
are two sibling species differing from each other in morphology, ecological preferences, and behavior, and no hybrids exist in nature. I have compared the genetic changes in 24 loci of 25 strains of
D. persimilis
from Mather, California, with those in
D. pseudoobscura
by the method of acrylamide gel electrophoresis. The proportion of the genome heterozygous in individual
D. persimilis
is 10.5 per cent, which is comparable to the heterogeneity found in similar
D. pseudoobscura
populations. I did not find any locus which is monomorphic or polymorphic for entirely different allele(s) than in
D. pseudoobscura
. The different frequencies of shared alleles in the two species can only be explained by selection acting differentially in these species, since the frequencies of different alleles at various loci in several populations of
D. pseudoobscura
are very similar or show a very stable pattern of association with the third chromosome gene arrangements.