bluuebunny/crossref_metadata_2025 huggingface dataset:
Curcumin in combination with visible light inhibits tumor growth in a xenograft tumor model
Authors: Dujic Jadranka , Kippenberger Stefan , Ramirez‐Bosca Ana , Diaz‐Alperi Joaquin , Bereiter‐Hahn Jürgen , Kaufmann Roland , Bernd August , Hofmann Matthias
Published: September 2008

It is known that curcumin, a dietary pigment from the plant Curcuma longa, inhibits cell proliferation and induces apoptosis in different cell lines; however, the therapeutic benefit is hampered by very low absorption after transdermal or oral application. Recent studies from our laboratory have demonstrated that curcumin at low concentrations (0.2–1 μg/ml) offered the described effects only when applied with UVA or visible light. Nevertheless, the in vivo efficacy of this combination is lacking. In the present study, we used a xenograft tumor model with human epithelial carcinoma A431 cells to test the effect of curcumin and visible light on tumor growth. It was found that tumor growth was significantly inhibited in mice that were i.p. injected with curcumin and consecutively irradiated with visible light. Furthermore, immunohistochemistry showed a reduction of Ki 67 expression, indicating a decrease of cycling cells and induction of apoptotic bodies. The effect on apoptosis was further confirmed by Western blot analysis showing enhanced activation of caspases‐9. Vice versa inhibition of extracellular regulated kinases (ERK) 1/2 and epidermal growth factor receptor (EGF‐R) was observed which may aid inhibition of proliferation and induction of apoptosis. In summary, the present findings suggest a combination of curcumin and light as a new therapeutic concept to increase the efficacy of curcumin in the treatment of cancer. © 2008 Wiley‐Liss, Inc.
Planning water management for secure food production in sub‐Saharan Africa
Authors: Ararso Girma Senbeta , Schultz Bart , Hollanders Peter
Published: September 2008

Sub‐Saharan Africa is a region with a high population density and fast population growth. Low economic status, poverty and food insecurity characterize the region. Most countries are regular food aid recipients. As the population growth rate is higher than the growth in food production, future conditions may become even worse, irrespective of the potential resources within the region. Land and water resources are quite sufficient to support food production. Only 16.8% (which is about 4% of the arable land) of the potentially irrigable land has been developed for irrigated agriculture. Drainage development is almost untouched and involves only 0.4% of the agricultural area.

In order to get an impression of promising options and possible constraints, with the help of the policy dialogue model PODIUM, this paper analyses the development of water management scenarios to improve food production in the region. Six sample countries – Cameroon, Democratic Republic of the Congo, Ethiopia, Nigeria, South Africa and Sudan – were considered for the analysis. Three water management scenarios were considered: focus on rainfed agriculture, focus on irrigated agriculture and a mixed scenario. The results of the analysis show that, with proper water management approaches, food security in the region is achievable. Copyright © 2008 John Wiley & Sons, Ltd.
Reference evapotranspiration estimation using adaptive neuro‐fuzzy inference systems
Authors: Doğan Emrah
Published: September 2008

Evapotranspiration, an important component in terrestrial water balance and net primary productivity models, is difficult to measure and estimate. In this study, the potential of the adaptive neuro‐fuzzy inference system (ANFIS) is investigated in modelling of daily grass crop reference evapotranspiration (ETo) obtained using the Penman–Monteith equation. Various combinations of daily climatic data, namely solar radiation, air temperature, relative humidity and wind speed, are used as inputs to the ANFIS so as to evaluate the degree of effect of each of these variables on daily Penman–Monteith estimated ETo. The results of the ANFIS model are compared with a multiple linear regression model. Mean square error, average absolute relative error and determination coefficient statistics are used as comparison criteria for evaluation of the model performance. The ANFIS technique whose inputs are solar radiation, air temperature, relative humidity and wind speed, gave mean square errors of 0.016, average absolute relative errors of 6.4%, and determination coefficients of 0.996 for Morgan Hill 139 station (San Francisco Bay, USA). Based on the comparisons, it was found that the ANFIS model could be successfully employed in estimating the daily ETo. Copyright © 2008 John Wiley & Sons, Ltd.
Beyond AICA riboside: In search of new specific AMP‐activated protein kinase activators
Authors: Guigas Bruno , Sakamoto Kei , Taleux Nellie , Reyna Sara M. , Musi Nicolas , Viollet Benoit , Hue Louis
Published: September 2008

5‐Aminoimidazole‐4‐carboxamide‐1‐β‐D‐ribofuranoside (AICA riboside) has been extensively used in vitro and in vivo to activate the AMP‐activated protein kinase (AMPK), a metabolic sensor involved in both cellular and whole body energy homeostasis. However, it has been recently highlighted that AICA riboside also exerts AMPK‐independent effects, mainly on AMP‐regulated enzymes and mitochondrial oxidative phosphorylation (OXPHOS), leading to the conclusion that new compounds with reduced off target effects are needed to specifically activate AMPK. Here, we review recent findings on newly discovered AMPK activators, notably on A‐769662, a nonnucleoside compound from the thienopyridone family. We also report that A‐769662 is able to activate AMPK and stimulate glucose uptake in both L6 cells and primary myotubes derived from human satellite cells. In addition, A‐769662 increases AMPK activity and phosphorylation of its main downstream targets in primary cultured rat hepatocytes but, by contrast with AICA riboside, does neither affect mitochondrial OXPHOS nor change cellular AMP:ATP ratio. We conclude that A‐769662 could be one of the new promising chemical agents to activate AMPK with limited AMPK‐independent side effects. © 2008 IUBMB IUBMB Life, 61(1): 18–26, 2009
Effects of choline‐deprivation on paracetamol‐ or phenobarbital‐induced rat liver metabolic response
Authors: Konstandi Maria , Segos Dimitrios , Galanopoulou Panagiota , Theocharis Stamatios , Zarros Apostolos , Lang Matti A. , Marselos Marios , Liapi Charis
Published: September 2008

Choline is an essential nutrient that seems to be involved in a wide variety of metabolic reactions and functions in both humans and rodents. Various pathophysiological states have been linked to choline deprivation (CD). The aim of the present study was to determine the effect of CD upon biochemical, histological and metabolic alterations induced by drugs that affect hepatic functional integrity and various drug metabolizing systems via distinct mechanisms. For this purpose, paracetamol (ACET) or phenobarbital (PB) were administered to male Wistar rats that were fed with standard rodent chow (normally fed, NF) or underwent dietary CD. The administration of ACET increased the serum aspartate aminotransferase levels in NF rats, while CD restricted this increase. On the other hand, ACET suppressed alkaline phosphatase levels only in CD rats. Moreover, CD prevented the PB‐induced increase of the mitotic activity of hepatocytes. The administration of ACET down‐regulated CYP1A2 and CYP2B1 expression in CD rats, while up‐regulating them in NF rats. The administration of PB suppressed CYP1A2 apoprotein levels in CD rats, whereas the drug had no effect on NF rats. The PB‐induced up‐regulation of CYP2B, CYP2E1 and CYP1A1 isozymes was markedly higher in CD than in NF rats. In addition, PB increased glutathione‐S‐transferase activity only in CD rats. Hepatic glutathione content (GSH) was suppressed by ACET in NF rats, whereas the drug increased GSH in CD rats. Our data suggest that CD has a significant impact on the hepatic metabolic functions, and in particular on those related to drug metabolism. Thus, CD may modify drug effectiveness and toxicity, as well as drug–drug interactions, particularly those related to ACET and PB. Copyright © 2008 John Wiley & Sons, Ltd.
The early phase of programmed cell death in Caco‐2 intestinal cells exposed to PTH
Authors: Calvo Natalia G. , Gentili Claudia R. , de Boland Ana Russo
Published: September 2008

The regulation of apoptosis is critical for ensuring the homeostasis of an organism. As such, the cell has derived various mechanisms to precisely control the balance between survival and apoptotic signaling. Parathyroid hormone (PTH) function as a major mediator of bone remodeling and as an essential regulator of calcium homeostasis. Depending on the cell type involved, PTH also inhibits or promotes the apoptosis. In a previous work we found that PTH promotes the apoptosis of human Caco‐2 intestinal cells. In the current study, we demonstrate, for the first time, that stimulation of Caco‐2 cells with PTH (10−8 M) results in the dephosphorylation and translocation of pro‐apoptotic protein Bad from the cytosol to mitochondria and release of cytochrome c and Smac/Diablo. The hormone also triggers mitochondria cellular distribution to the perinuclear region, morphological features consistent with apoptosis. PTH increases the enzymatic activity of caspase‐3 (48 h) that is also evidenced from the appearance of its cleaved fragments in western blot experiments. Moreover, active caspase‐3 is present in nucleus after PTH treatment. In addition, a caspase‐3 substrate, poly (ADP‐ribose) polymerase (PARP), is degraded by 48 h of PTH treatment. Taken together, our results suggest that, in Caco‐2 cells, the induction of apoptosis in response to PTH is mediated by translocation of mitochondria to the perinuclear region, dephosphorylation of Akt, dephosphorylation of Bad and its movement to the mitochondria and subsequent release of cytochrome c and Smac/Diablo which result in activation of downstream caspase‐3. J. Cell. Biochem. 105: 989–997, 2008. © 2008 Wiley‐Liss, Inc.
The camera perspective bias: a case study
Authors: Landström Sara , Af Hjelmsäter Emma Roos , Granhag Pär Anders
Published: September 2008

In this case study, we examined how variations of the camera perspective affect adults' assessment of veracity in a real‐life high‐stake situation; a masked male confessing to a very serious crime. The interview, conducted by one of Sweden's most awarded journalists, lasted 30 minutes and consisted of over 100 detailed questions about the crime. The interview was videotaped simultaneously by three cameras positioned at different locations, each taking a unique visual perspective. One camera focused on the suspect only, one on the interviewer only, and one equally on the suspect and the interviewer. Each videotape was shown to 32 adult observers (N = 96) who were asked to assess the suspect's veracity and to report subjective cues justifying their veracity assessment. The results confirmed the camera perspective bias, by showing that the observers in the ‘suspect only’ condition assessed the confession as significantly more reliable than did the observers in the ‘interviewer only’ condition. The observers reported that they relied heavily on verbal cues when assessing the confession, and particularly regarding confidence and consistency. Copyright © 2008 John Wiley & Sons, Ltd.
Urnaloricus gadi nov. gen. et nov. sp. (Loricifera, Urnaloricidae nov. fam.), an aberrant Loricifera with a viviparous pedogenetic life cycle
Authors: Heiner Iben , Kristensen Reinhardt Møbjerg
Published: September 2008

A new species of Loricifera, Urnaloricus gadi nov. gen. et nov. sp., is described from the Faroe Bank, located Southwest of the Faroe Islands, North Atlantic. The new species does not fit into any known families of Loricifera and therefore it is grouped into a new family Urnaloricidae nov. fam. The new species is characterized by having a very complicated life cycle that involves a large cyst‐like mega‐larva, two reduced larval instars and the Higgins‐larvae eating their maternal stage from within. An adult stage is missing. This form of reproduction is called viviparous pedogenesis and normally is found only in nematodes and insects. In the life cycle of Urnaloricidae nov. fam., there are two types of free‐living larval stages: a Higgins‐larva and a mega‐larva. The latter is found in two different forms, a pre‐ and a cyst‐forming mega‐larva. Additionally, there are two reduced life history stages, the reduced larval stage (probably a postlarva) and the ghost‐larval stage inside the cyst‐forming mega‐larva. The external morphology of the two forms of mega‐larvae is much reduced, e.g., the introvert has only a few rows of scalids when compared with the Higgins‐larva. The pre mega‐larva is free‐living and can sometimes be covered with coccoliths. Internally, a large ovary with a few oocytes, a digestive system, and an internal armature with retracted scalids are present. The pre mega‐larva presumably molts into a cyst‐forming mega‐larva and thereby the ovary is now seen inside the cyst‐forming mega‐larva. The cyst‐forming mega‐larva has the same structures as in the pre mega‐larva though here the scalids are protruded and there is a gonopore. Inside the cyst‐forming mega‐larva the ovary produces more oocytes and begins to fill out the entire lumen. At this stage the cyst‐forming mega‐larva molts first to the presumed postlarval stage, and then this stage molts to a ghost‐larva. Hence, the ovary now matures inside the ghost‐larva, which is surrounded by both the cuticle of the reduced postlarval stage and the cuticle of the cyst‐forming mega‐larva. The oocytes mature into eggs, and then into embryos and finally into Higgins‐larvae while reabsorbing all the tissue of their maternal stage, the ghost‐larva. During this maturation the cuticle of the cyst‐forming mega‐larva starts to harden and become cyst‐like. The fully developed Higgins‐larvae emerge through the gonopore of the cyst‐forming mega‐larva by penetrating the thin cuticles of the ghost‐larva and the postlarva. The embryos have holoblastic radial cleavage and later a fluid‐filled blastocoel is formed. The eggshells are extremely elastic; hence, they can become very elongated as the embryos mature into Higgins‐larvae. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc.
Enzyme‐ and immunohistochemical aspects of skeletal muscle fibers in brown bear (Ursus arctos)
Authors: Smerdu Vika , Čehovin Tamara , Štrbenc Malan , Fazarinc Gregor
Published: September 2008

To further elucidate the pattern of MHC isoform expression in skeletal muscles of large mammals, in this study the skeletal muscles of brown bear, one of the largest mammalian predators with an extraordinary locomotor capacity, were analyzed. Fiber types in longissimus dorsi, triceps brachii caput longum, and rectus femoris muscles were determined according to the myofibrillar ATPase (mATPase) histochemistry and MHC isoform expression, revealed by a set of antibodies specific to MHC isoforms. The oxidative (SDH) and glycolytic enzyme (α‐GPDH) capacity of fibers was demonstrated as well. By mATPase histochemistry five fiber types, i.e., I, IIC, IIA, IIAX, IIX were distinguished. Analyzing the MHC isoform expression, we assume that MHC‐I, ‐IIa, and ‐IIx are expressed in the muscles of adolescent bears. MHC‐I isoform was expressed in Type‐I fibers and coexpressed with presumably ‐IIa isoform, in Type‐IIC fibers. Surprisingly, two antibodies specific to rat MHC‐IIa stained those fast fibers, that were histochemically and immunohistochemically classified as Type IIX. This assumption was additionally confirmed by complete absence of fiber staining with antibody specific to rat MHC‐IIb and all fast fiber staining with antibody that according to our experience recognizes MHC‐IIa and ‐IIx of rat. Furthermore, quite high‐oxidative capacity of all fast fiber types and their weak glycolytic capacity also imply for MHC‐IIa and ‐IIx isoform expression in fast fibers of bear. However, in adult, full‐grown animal, only MHC‐I and MHC‐IIa isoforms were expressed. The expression of only two fast isoforms in bear, like in many other large mammals (humans, cat, dog, goat, cattle, and horse) obviously meets the weight‐bearing and locomotor demands of these mammals. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc.
Ontogeny of the complex sperm in the macrostomid flatworm Macrostomum lignano (Macrostomorpha, Rhabditophora)
Authors: Willems Maxime , Leroux Frederic , Claeys Myriam , Boone Mieke , Mouton Stijn , Artois Tom , Borgonie Gaëtan
Published: September 2008

Spermiogenesis in Macrostomum lignano (Macrostomorpha, Rhabditophora) is described using light‐ and electron microscopy of the successive stages in sperm development. Ovoid spermatids develop to highly complex, elongated sperm possessing an undulating distal (anterior) process (or “feeler”), bristles, and a proximal (posterior) brush. In particular, we present a detailed account of the morphology and ontogeny of the bristles, describing for the first time the formation of a highly specialized bristle complex consisting of several parts. This complex is ultimately reduced when sperm are mature. The implications of the development of this bristle complex on both sperm maturation and the evolution and function of the bristles are discussed. The assumed homology between bristles and flagellae questioned. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc.
Cadmium modulates proliferation and differentiation of human neuroblasts
Authors: Gulisano Massimo , Pacini Stefania , Punzi Tiziana , Morucci Gabriele , Quagliata Sara , Delfino Giovanni , Sarchielli Erica , Marini Mirca , Vannelli Gabriella B.
Published: September 2008

Cadmium is an environmental pollutant inducing numerous pathological effects, including neurological disorders and brain diseases. However, little is known about the molecular mechanisms of cadmium in affecting neurons and in inducing neurotoxicity in the development of the human brain. We have recently established, cloned, and propagated in vitro a primary long‐term cell culture (FNC‐B4) obtained from the human fetal olfactory neuroepithelium. In the present study, we show that different concentrations of cadmium chloride (CdCl2) induced dose‐dependent biological effects in FNC‐B4 cells. A low concentration (10 μM) of CdCl2 stimulated neuroblast growth, whereas a high concentration (100 μM) inhibited the growth and the viability of neuroblasts inducing morphological and cytoskeletal alterations as well as apoptotic cell death. We also observed that CdCl2 affected, in a dose‐dependent manner, the differentiation of FNC‐B4 neuroblasts, with increased mRNA and protein levels of differentiation markers and decreased expression levels of neuronal stem markers. Furthermore, differentiated cells co‐expressed glial and neuronal markers. We suggest that CdCl2 in FNC‐B4 neuroblasts might represent a selective cue by which, in a heterogeneous primary culture, the more differentiated mature cells die, whereas the undifferentiated cells, at the same time glial and neuronal progenitors, are forced to access a state of differentiation. © 2008 Wiley‐Liss, Inc.
The amino terminus of tau inhibits kinesin‐dependent axonal transport: Implications for filament toxicity
Authors: LaPointe Nichole E. , Morfini Gerardo , Pigino Gustavo , Gaisina Irina N. , Kozikowski Alan P. , Binder Lester I. , Brady Scott T.
Published: September 2008

The neuropathology of Alzheimer's disease (AD) and other tauopathies is characterized by filamentous deposits of the microtubule‐associated protein tau, but the relationship between tau polymerization and neurotoxicity is unknown. Here, we examined effects of filamentous tau on fast axonal transport (FAT) using isolated squid axoplasm. Monomeric and filamentous forms of recombinant human tau were perfused in axoplasm, and their effects on kinesin‐ and dynein‐dependent FAT rates were evaluated by video microscopy. Although perfusion of monomeric tau at physiological concentrations showed no effect, tau filaments at the same concentrations selectively inhibited anterograde (kinesin‐dependent) FAT, triggering the release of conventional kinesin from axoplasmic vesicles. Pharmacological experiments indicated that the effect of tau filaments on FAT is mediated by protein phosphatase 1 (PP1) and glycogen synthase kinase‐3 (GSK‐3) activities. Moreover, deletion analysis suggested that these effects depend on a conserved 18‐amino‐acid sequence at the amino terminus of tau. Interestingly, monomeric tau isoforms lacking the C‐terminal half of the molecule (including the microtubule binding region) recapitulated the effects of full‐length filamentous tau. Our results suggest that pathological tau aggregation contributes to neurodegeneration by altering a regulatory pathway for FAT. © 2008 Wiley‐Liss, Inc.
Laminin peptide YIGSR and its receptor regulate sensory axonal response to the chemoattractive guidance cue in the chick embryo
Authors: Masuda Tomoyuki , Sakuma Chie , Kobayashi Kenta , Kikuchi Kazufumi , Soda Emi , Shiga Takashi , Kobayashi Kazuto , Yaginuma Hiroyuki
Published: September 2008

During early development, centrally projecting dorsal root ganglion (DRG) neurons extend their axons toward the dorsal spinal cord. We previously reported the involvement of dorsal spinal cord‐derived chemoattraction in this projection (Masuda et al. [ 2007] Neuroreport 18:1645–1649). However, the molecular nature of this attraction is not clear. Here we show that laminin‐1 (α1β1γ1) is expressed strongly along the pathway of DRG axons and that its 67‐kDa receptor (67LR) is present on DRG cells. This evidence suggests that laminin‐1‐67LR signaling may be involved in DRG axonal guidance. By employing culture assays, we show that laminin‐1 or the YIGSR peptide, a soluble peptide of the laminin β1 chain, promotes the DRG axonal response to dorsal spinal cord‐derived chemoattraction. By using a function‐blocking antibody against 67LR, we show that the anti‐67LR antibody blocks the modulation of DRG axonal response by the YIGSR peptide in vitro. Furthermore, the in ovo injection of the anti‐67LR antibody inhibits the DRG axonal growth toward the dorsal spinal cord. These results provide evidence that the YIGSR peptide promotes dorsal spinal cord‐derived chemoattraction via 67LR to contribute to the formation of the initial trajectories of developing DRG axons. © 2008 Wiley‐Liss, Inc.
In vitro activity of dalbavancin against enterococci isolates from wild animals, pets, poultry and humans in Portugal
Authors: Poeta Patricia , Radhouani Hajer , Sargo Roberto , Igrejas Gilberto
Published: September 2008

Dalbavancin is a new new semisynthetic teicoplanin‐related lipoglycopeptide with activity against gram‐positive organisms. We investigated the activity of dalbavancin against faecal enterococci isolates from wild animals, pets, poultry and healthy humans in Portugal.

The in vitro activity of dalbavancin was determined by the microbroth dilution method according to the Clinical Laboratory Standards Institute (CLSI) guidelines in 589 enterococci of different species and origins. All vancomycin‐susceptible Enterococcus spp. were inhibited by ≤0.25 mg/l dalbavancin. Although vancomycin‐resistant‐enterococci (VRE) showed higher dalbavancin MIC values (16 mg/l), the isolates that exhibited the VanC resistance phenotype were inhibited at dalbavancin concentrations ≤0.125 mg/l. Only van A isolates were not inhibited by low concentrations of dalbavancin since van A strains showed higher dalbavancin MIC values (16 mg/l). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation and characterization of phenol degrading yeast
Authors: Patel Riddhi , Rajkumar Shalini
Published: September 2008

A phenol degrading yeast isolate was identified and characterized from the soil sample collected from a landfill site, in Ahmedabad, India, by plating the soil dilutions on Sabouraud's Dextrose Agar. The microscopic studies and biochemical tests indicated the isolate to be Saccharomyces cerevisiae. The phenol degrading potential of the isolate was measured by inoculation of pure culture in the mineral medium containing various phenol concentrations ranging from 100 to 800 mg l–1 and monitoring phenol disappearance rate at regular intervals of time. Growth of the isolate in mineral medium with various phenol concentrations was monitored by measuring the turbidity (OD600 nm). The results showed that the isolated yeast was tolerant to phenol up to 800 mg–1. The phenol degradation ranged from 8.57 to 100% for the concentration of phenol from 800 mg l–1 to 200 mg l–1, respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of the Penicillium chrysogenum antifungal protein (PAF) on barley powdery mildew and wheat leaf rust pathogens
Authors: Barna Balázs , Leiter Éva , Hegedűs Nikoletta , Bíró Tamás , Pócsi István
Published: September 2008

The small molecular mass antifungal protein of Penicillium chrysogenum (PAF) inhibited the growths of two obligate biotrophic fungal pathogens, Blumeria graminis f. sp. hordei and Puccinia recondita f.sp. tritici and, hence, mitigated the symptoms of barley powdery mildew and wheat leaf rust infections, respectively. PAF also affected adversely the germination of B. graminis conidia and P. recondita uredospores causing degenerative branching of germ tubes. Since powdery mildews and rusts cause serious economic losses the potential applicability of PAF to control these plant diseases is promising. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A high‐resolution pollen and geochemical analysis of late Holocene human impact and vegetation history in southern Cumbria, England
Authors: Coombes Paul M. V. , Chiverrell Richard C. , Barber Keith E.
Published: September 2008

The historic era, which in Cumbria begins with the Roman invasion of AD 71, is a frequently neglected period in palaeoecological research, but its study can bring benefits in improving knowledge of landscape history and in understanding the significance and limitations of palaeoecological records. Pollen and geochemical data are presented for late Holocene records from Deer Dyke and Hulleter Mosses in southern Cumbria. The records show initially low levels of anthropogenic impact, followed by a phase of forest clearance and mixed agriculture from the 7th to 11th centuries AD. The timing of these clearances suggests that they were initially Anglo‐Saxon in origin, rather than Norse. Further clearances in the 16th century AD are interpreted as a response to monastic dissolution and late Tudor population pressures; the landscapes reached their contemporary form following extensive clearances in the 17th century AD. Silicon and titanium concentrations at Deer Dyke Moss were used to reconstruct past levels of atmospheric dust loading, which is broadly related to soil erosion. Geochemical influx was found to peak during periods of landscape transition rather than from established land use. This relationship with pollen data is thought to reflect the predominantly low levels of anthropogenic impact in the region, which changes as substantial woodland clearances during the 16th century AD and continuous land use pressure since then have greatly increased the supply of airborne dust. Copyright © 2008 John Wiley & Sons, Ltd.
Performance comparison of free and immobilised chicken liver esterase inhibited by four different pesticides
Authors: Xu Fei , Yu Wei‐Jing , Sun Da‐Wen , Xu Xue‐Qin , Hua Tse‐Chao
Published: September 2008

BACKGROUND: In enzyme inhibition‐based biosensors for the detection of organophosphate and carbamate pesticides, the biological element is the immobilised esterase which is inhibited selectively by the pesticides. The free chicken liver esterase, which possesses comparable inhibition response to the pesticides as AChE, has been reported. However, the responses to the pesticides are different between the free and immobilised enzyme due to the diffusion limitation. Therefore, in this study four typical pesticides were selected to compare the ability of free and (ion exchange) immobilised chicken enzyme for pesticide detection and reasons for the difference were investigated.

RESULTS: For dichlorvos and malathion at a concentration of 0.1 mg L−1, the inhibition of the immobilised enzyme was 26.98% and 48.72%, respectively, higher than that for the free enzyme, while the percentage inhibition of free and immobilised enzyme differed very little for trichlorfon at 0.1 mg L−1. In the meantime, carbaryl at a concentration of 2.5 mg L−1 showed a 17.72% inhibition for immobilised enzyme which was 13.64% higher than that for the free enzyme. The Michaelis constant of immobilised enzyme was lower than that of the free one and suitable pH values for the free and immobilised enzyme were 7.5 and 8.0, respectively.

CONCLUSIONS: The sensitivity of chicken liver esterase to the pesticide inhibition could be improved by immobilisation. Smaller Km and a lower pH for the micro‐environment of immobilised enzyme should result in higher percentage inhibition compared with that of the free enzyme. Copyright © 2008 Society of Chemical Industry
Determination of short‐chain branching content in polyethylene by pyrolysis comprehensive multidimensional gas chromatography using low thermal mass column technology
Authors: Eckerle Patric , Pursch Matthias , Cortes Hernan J. , Sun Kefu , Winniford Bill , Luong Jim
Published: September 2008

A research effort was undertaken to utilize the pyrolysis process to create fragments of polyethylene that could be indicative of branching, and allow quantitiation of said short‐chain branches by pyrolysis comprehensive 2‐D GC (Py‐GC×GC). Several strategies for sample introduction and pyrolysis such as the in‐column pyrolysis device and the programmed temperature vaporizer (PTV) were studied. The chromatographic separations were executed using low‐thermal mass (LTM) comprehensive 2‐D GC (GC×GC). A series of polyethylene‐co‐hexene samples were analyzed and a linear correlation of 1‐hexene content with branching peak ratio was found. Correlation coefficients were determined as 0.97 for the measurements performed.
Analysis of aldehydes via headspace SPME with on‐fiber derivatization to their O‐(2,3,4,5,6‐pentafluorobenzyl)oxime derivatives and comprehensive 2D‐GC‐MS
Authors: Schmarr Hans‐Georg , Sang Wei , Ganß Sebastian , Fischer Ulrich , Köpp Benedikt , Schulz Carsten , Potouridis Theodoros
Published: September 2008

A method for the analysis of the homologous series of alkanals, (E)‐2‐alkenals, and (E,E)‐2,4‐alkadienals is described utilizing a headspace solid‐phase microextraction (HS‐SPME) step and on‐fiber derivatization with O‐(2,3,4,5,6‐pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Oxime derivatives formed on the fiber are desorbed in the gas chromatographic injector and analyzed by comprehensive 2‐D GC coupled to quadrupole MS (GC×GC‐qMS). Selecting specific fragment ions within the electron impact mass spectra of the oxime derivatives provides a suitable method for the target analysis of these aldehyde classes, which furthermore benefits from the increased separation efficiency by GC×GC. The analysis of higher molecular weight aldehydes is described in wine and grape seed oil as examples. Quantification of the aldehydes utilizes a stable isotope dilution analysis (SIDA) assay with octan‐d16‐al as isotopomeric internal standard. Besides the selectivity and sensitivity of aldehyde analysis using PFBHA derivatives, critical aspects on background level contamination and repeatability of the sample preparation method are discussed. Optimization of GC×GC‐qMS parameters allowed a considerable saving of the cryogenic medium, involving additional (unmodulated) conditioning runs, rendering the method more amenable to routine analysis.
Viability of human septal cartilage after 1.45 µm diode laser irradiation
Authors: Choi Ick‐Soo , Chae Yong‐Seok , Zemek Allison , Protsenko Dmitry E. , Wong Brian
Published: September 2008

Background and Objectives

Chondrocyte viability following laser irradiation and reshaping has not been established for human nasal septal cartilage. Knowledge of the relationship between thermal injury and laser dosimetry is needed in order to optimize septal laser cartilage reshaping. The objective of this study was to determine the depth and width of thermal injury in human septal cartilage following laser irradiation.

Study Design/Materials and Methods

Excess fresh nasal septal cartilage sections from rhinoplasty or septoplasty operations were irradiated using a 1.45 µm diode laser 1.25–3.6 W (2.8 mm spot diameter) with 1 second fixed exposure time, and then at exposure times of 1–4 seconds for a fixed power of 1.25 W. An infrared camera recorded surface temperature profiles during irradiation, and the temperature data were incorporated into a rate process model to numerically estimate thermal damage. Calcein AM and ethidium homodimer‐1 fluorescent dyes combined with confocal laser microscopy (CLM) were used to measure thermal damage.

Results

CLM demonstrated clear demarcation between dead and living cells following irradiation. The extent of non‐viable chondrocyte distributions increased with power and exposure time. The maximum depths of injury were 1,012 and 1,372 µm after 3.6 W 1 second and 1.25 W 4 seconds irradiation respectively. The damage predictions made by the rate process model underestimated thermal injury when compared with CLM measurements.

Conclusions

The assay system identified regions of non‐viable chondrocytes in human septal cartilage and defined how thermal injury varies with dosimetry when using a 1.45 µm diode laser. Lesers Surg. Med. 40:562–569, 2008. © 2008 Wiley‐Liss, Inc.
Evaluation of laser beam profile in soft tissue due to compression, glycerol, and micro‐needling
Authors: Kang Heesung , Son Taeyoon , Yoon Jinhee , Kwon Kiwoon , Nelson J. Stuart , Jung Byungjo
Published: September 2008

Background and Objectives

Various methods have been suggested to enhance photon density in biological tissues in an attempt to maximize the efficacy of laser therapy. In this study, the effects of tissue compression, glycerol, and micro‐needling methods on the laser beam profile (LBP) were investigated by quantitatively evaluating the spatial distribution of subsurface tissue photon density.

Study Design/Materials and Methods

The LBP in tissue was obtained by imaging the laser beam transmitted through ex vivo porcine skin samples. The independent and combinational effects of tissue compression, glycerol, and micro‐needling methods on the LBP were evaluated by quantitatively analyzing the full width at half‐maximum (FWHM), maximum intensity, and total intensity at FWHM.

Results

Experimental results indicate the enhancement of the quality of Gaussian beam profile in ex vivo porcine skin. Glycerol and tissue compression resulted in an increase of maximum and total intensity and a decrease of FWHM. Tissue compression in conjunction with glycerol was determined to be the most effective method for enhancing the LBP. The topical application of glycerol in conjunction with micro‐needling reduced the time period to optically clear tissue, which resulted in a further increase of subsurface tissue photon density.

Conclusion

Tissue compression, glycerol, and micro‐needling methods might be used independently or in combination to effectively enhance the photon density delivered to target chromophores in subsurface tissue, thus improving the LBP quality. Lesers Surg. Med. 40:570–575, 2008. © 2008 Wiley‐Liss, Inc.
Effects of 808 nm low‐power laser irradiation on the muscle contraction of frog gastrocnemius
Authors: Komatsu Mitsuaki , Kubo Tomihiro , Kogure Shinichi , Matsuda Yoshiki , Watanabe Kazuhiro
Published: September 2008

Background and objectives

The efficacy of low‐power laser irradiation (LLI) on muscle fibers remains unclear; therefore, we examined the effect of LLI (808 nm: 60 or 100 mW) on muscle contraction and conducted waveform analyses of the twitch curve, including alterations in the peak amplitudes of tension (AMP), latency (LAT), contraction period (CP), and relaxation period (RP).

Study design/materials and methods

The sciatic nerve‐gastrocnemius muscles of 35 frogs (Xenopus laevis) were prepared. In Experiment 1, continuous stimulation for gastrocnemius contraction was delivered to the sciatic nerve (10 minutes); the experimental group simultaneously received LLI. In Experiment 2, two sets of stimulation and cessation (2 minutes each) were repeated after the initial stimulation period (2 minutes); the experimental group received LLI during the resting period.

Results and conclusions

In Experiment 1, 60 mW LLI significantly facilitated an attenuation of AMP and maintained a smaller prolongation of CP (P<0.05), whereas 100 mW LLI significantly influenced a retardation of AMP attenuation and LAT prolongation (P<0.05). In Experiment 2, 100 mW LLI significantly influenced AMP attenuation and LAT prolongation by retardation (P<0.05); almost no effects were obtained in the case of 60 mW LLI. These results suggest that 808 nm LLI influences both synaptic signal transmission at the neuromuscular junction and excitation–contraction coupling in the muscle fibers, but not the relaxation process. We conclude that LLI at relatively high doses can influence muscle by retarding AMP attenuation and LAT prolongation. Lesers Surg. Med. 40:576–583, 2008. © 2008 Wiley‐Liss, Inc.
Thermoforming of tracheal cartilage: Viability, shape change, and mechanical behavior
Authors: Chae Yongseok , Protsenko Dmitriy , Holden Paul K. , Chlebicki Cara , Wong Brian J.F.
Published: September 2008

Background and Objectives

Trauma, emergent tracheostomy, and prolonged intubation are common causes of severe deformation and narrowing of the trachea. Laser technology may be used to reshape tracheal cartilage using minimally invasive methods. The objectives of this study were to determine: (1) the dependence of tracheal cartilage shape change on temperature and laser dosimetry using heated saline bath immersion and laser irradiation, respectively, (2) the effect of temperature on the mechanical behavior of cartilage, and (3) tissue viability as a function of laser dosimetry.

Materials and Methods

Ex vivo rabbit trachea cartilage specimens were bent and secured around a cylinder (6 mm), and then immersed in a saline bath (45 and 72°C) for 5–100 seconds. In separate experiments, tracheal specimens were irradiated with a diode laser (λ = 1.45 µm, 220–400 J/cm2). Mechanical analysis was then used to determine the elastic modulus in tension after irradiation. Fluorescent viability assays combined with laser scanning confocal microscopy (LSCM) were employed to image and identify thermal injury regions.

Results

Shape change transition zones, between 62 and 66°C in the saline heating bath and above power densities of 350 J/cm2(peak temperatures 65±10°C) for laser irradiation were identified. Above these zones, the elastic moduli were higher (8.2±4 MPa) than at lower temperatures (4.5±3 MPa). LSCM identified significant loss of viable chondrocytes within the laser‐irradiation zones.

Conclusion

Our results indicate a change in mechanical properties occurs with laser irradiation and further demonstrates that significant thermal damage is concurrent with clinically relevant shape change in the elastic cartilage tissues of the rabbit trachea using the present laser and dosimetry parameters. Lesers Surg. Med. 40:550–561, 2008. © 2008 Wiley‐Liss, Inc.
Disruption of the blood–brain barrier following ALA‐mediated photodynamic therapy
Authors: Hirschberg Henry , Uzal Francisco A. , Chighvinadze David , Zhang Michelle J. , Peng Qian , Madsen Steen J.
Published: September 2008

Background and Objective

Photodynamic therapy (PDT) is a local antineoplastic treatment with the potential for tumor cell specificity. PDT using either hematoporphyrin derivatives or 5‐aminolevulinic acid (ALA) has been reported to induce brain edema indicating disruption of the blood–brain barrier (BBB). We have evaluated the ability of ALA‐mediated PDT to open the BBB in rats. This will permit access of chemotherapeutic agents to brain tumor cells remaining in the resection cavity wall, but limit their penetration into normal brain remote from the site of illumination.

Study Design/Materials and Methods

ALA‐PDT was performed on non‐tumor bearing inbred Fischer rats at increasing fluence levels. Contrast T1‐weighted high field (3 T) magnetic resonance imaging (MRI) scans were used to monitor the degree of BBB disruption which could be inferred from the intensity and volume of the contrast agent visualized.

Results

PDT at increasing fluence levels between 9 and 26 J demonstrated an increasing contrast flow rate. A similar increased contrast volume was observed with increasing fluence rates. The BBB was found to be disrupted 2 hours following PDT and 80–100% restored 72 hours later at the lowest fluence level. No effect on the BBB was observed if 26 J of light was given in the absence of ALA.

Conclusion

ALA‐PDT was highly effective in opening the BBB in a localized region of the brain. The degradation of the BBB was temporary in nature at fluence levels of 9 J, opening rapidly following treatment and significantly restored during the next 72 hours. No signs of tissue damage were seen on histological sections at this fluence level. However, higher fluences did demonstrate permanent tissue changes localized in the immediate vicinity of the light source. Lesers Surg. Med. 40:535–542, 2008. © 2008 Wiley‐Liss, Inc.
Temporary hair removal by low fluence photoepilation: Histological study on biopsies and cultured human hair follicles
Authors: Roosen Guido F. , Westgate Gillian E. , Philpott Mike , Berretty Paul J.M. , Nuijs Tom (A.M.) , Bjerring Peter
Published: September 2008

Background and Objectives

We have recently shown that repeated low fluence photoepilation (LFP) with intense pulsed light (IPL) leads to effective hair removal, which is fully reversible. Contrary to permanent hair removal treatments, LFP does not induce severe damage to the hair follicle. The purpose of the current study is to investigate the impact of LFP on the structure and the physiology of the hair follicle.

Study Design/Materials and Methods

Single pulses of IPL with a fluence of 9 J/cm2 and duration of 15 milliseconds were applied to one lower leg of 12 female subjects, followed by taking a single biopsy per person, either immediately, or after 3 or 7 days. Additionally, we present a novel approach to examine the effects of LFP, in which ex vivo hairy human scalp skin was exposed to IPL pulses with the same parameters as above, followed by isolation and culturing of the hair follicles over several days. Samples were examined histologically and morphologically.

Results

The majority of the cultured follicles that had been exposed to LFP treatment showed a marked treatment effect. The melanin containing part of the hair follicle bulb was the target and a catagen‐like transformation was observed demonstrating that hair formation had ceased. The other follicles that had been exposed to LFP showed a less strong or no response. The skin biopsies also revealed that the melanin‐rich region of the hair follicle bulb matrix was targeted; other parts of the follicle and the skin remained unaffected. Catagen/telogen hair follicles were visible with unusual melanin clumping, indicating this cycle phase was induced by the IPL treatment.

Conclusions

Low fluence photoepilation targets the pigmented matrix area of the anagen hair follicle bulb, causing a highly localized but mild trauma that interrupts the hair cycle, induces a catagen‐like state and eventually leads to temporary loss of the hair. Lesers Surg. Med. 40:520–528, 2008. © 2008 Wiley‐Liss, Inc.
Oncogenic and ligand‐dependent activation of KIT/PDGFRA in surgical samples of imatinib‐treated gastrointestinal stromal tumours (GISTs)
Authors: Negri T , Bozzi F , Conca E , Brich S , Gronchi A , Bertulli R , Fumagalli E , Pierotti MA , Tamborini E , Pilotti S
Published: September 2008

As the range of receptor tyrosine kinase (RTK) inhibitors widens, a detailed understanding of the activating mechanisms of KIT/platelet‐derived growth factor receptor (PDGFR)A and the related downstream pathways involved in the development and maintenance of GISTs is becoming increasingly important. We analysed areas with different histological response ratios in surgical specimens taken from imatinib‐treated and untreated GIST patients in order to investigate KIT and PDGFRA expression/activation, the presence of their cognate ligands and the activation of downstream signalling, by means of biochemistry, immunohistochemistry and flow cytometry. All of the cases showed KIT and PDGFRA co‐expression. In addition to the oncogenic activation of mutated receptors, activation of wild‐type KIT and wild‐type PDGFRA, sustained by heterodimerization and an autocrine–paracrine loop, was demonstrated by the presence of their specific ligands, stem cell factor (SCF) and PDGFA. To confirm RTK activation further, all of the samples (including those with the highest regression ratios) were investigated for downstream effectors, and all proved to have activated downstream signalling. The results show that after the mutated receptors are switched off, heterologous wild‐type receptors become important in imatinib‐treated GISTs as a means of maintaining signalling activation. Taken together, our findings suggest that drugs targeting wild‐type receptors should be tested in imatinib‐treated GIST patients. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
E2Fs mediate a fundamental cell‐cycle deregulation in high‐grade serous ovarian carcinomas
Authors: De Meyer T , Bijsmans ITGW , Van de Vijver KK , Bekaert S , Oosting J , Van Criekinge W , van Engeland M , Sieben NLG
Published: September 2008

Several studies described a role for the E2F/Rb pathway in ovarian serous carcinomas (SCAs). Since E2F/Rb pathway deregulation is a general hallmark of human cancer, it remains unclear whether this deregulation is of particular importance in SCAs or whether it reflects a common oncological feature. Here, we have clarified this issue by the examination of microarray expression profiles of SCAs and particularly by the comparison with another, less malignant, ovarian cancer type, serous borderline tumours (SBTs). Results were validated by quantitative RT‐PCR, both on the microarray samples and on an independent panel, and TP53 mutation analysis was performed. This integrated analysis revealed a significant increase in the expression of the transcription factors E2F1 and E2F3 in SCAs, when compared to SBTs. This was associated with vast overexpression of E2F target genes in SCAs compared to SBTs. High‐grade SCAs in particular exhibited a major deregulated E2F target expression pattern. Generally, overexpression of E2F targets in SCAs appeared to be well structured since those targets considered negative regulators of the cell cycle or promoters of apoptosis were usually not overexpressed in SCAs. Similar to E2F target deregulation, TP53 mutations were identified in SCA3s, to a lesser extent in SCA1s, and not in SBTs. These results suggest that a structured, generally up‐regulated E2F transcription factor activity is associated with a global cell‐cycle disturbance in high‐grade SCAs and exceeds typical E2F/Rb pathway disruption in tumours, at least compared with SBTs. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.