bluuebunny/crossref_metadata_2025 huggingface dataset:
Retention of mobile water during dehydration in the desiccation‐tolerant grass Eragrostis nindensis
Authors: Balsamo Ronald A. , Vander Willigen Clare , Boyko Walter , Farrant Jill
Published: August 2005

Leaf tensile strength was measured for the drought‐tolerant grass Eragrostis curvula and the desiccation‐tolerant grass E. nindensis when fully hydrated, partially dehydrated, naturally air‐dried, and flash‐dried. Leaf tensile strength increased in intact, air‐dried leaves of E. curvula but not for similarly treated leaves of E. nindensis. Examination of leaf cross‐sections by light microscopy and histochemical staining for lignins failed to show any significant structural differences between the two species in the hydrated state. When leaves were flash‐dried, the tensile strength of E. curvula remained unchanged from leaves dried naturally, while there was a marked increase in the tensile strength of flash‐dried leaves of E. nindensis. Proton NMR indicated that the desiccation‐tolerant E. nindensis retained mobile water when leaf relative water content was less than 20% if dried naturally but not if flash‐dried, whereas no mobile water was detected in leaves of E. curvula when dried either naturally or with flash‐drying to below 20% relative water content. This behaviour suggests a fundamental difference in strategy for surviving water loss in vegetative tissues between desiccation‐tolerant species and drought‐tolerant species.
Differential photosynthetic compensatory mechanisms exist in the immutans mutant of Arabidopsis thaliana
Authors: Baerr Jillian N. , Thomas Jeremy D. , Taylor Brian G. , Rodermel Steven R. , Gray Gordon R.
Published: August 2005

Variegation in the immutans (im) mutant of Arabidopsis is induced by a nuclear recessive gene. The white leaf sectors of im contain abnormal plastids lacking pigments and organized lamellae, whereas the green leaf sectors possess normal‐appearing chloroplasts. IMMUTANS codes for a thylakoid membrane terminal oxidase that functions as a safety valve to dissipate excess energy. Previous studies have shown that the green sectors of im, regardless of illumination conditions, have anatomical adaptations that are reminiscent of acclimation to high‐light stress. It has been suggested that these adaptations provide a means of enhancing photosynthesis to feed the white sectors and maximize plant growth. We have utilized Chl fluorescence imaging to better understand these compensatory mechanisms using, as our experimental material, im leaves with predominantly green (img) or predominantly white (imw) tissues. The samples were examined under conditions of normal growth or high‐light stress (photoinhibition). Steady‐state fluorescence quenching revealed that the green sectors of the imw leaves had lower levels of 1 − qp than the img leaves, and that this was accompanied by increased electron transport rates. In response to short‐term high‐light exposure, the green sectors of the imw leaves displayed enhanced non‐photochemical quenching (NPQ), which correlated with increased xanthophyll pool sizes and increased amounts of several different Lhcb polypeptides and the PsbS protein. In summary, our data show that, compared with primarily green leaves (img), the green sectors of predominantly white leaves (imw) have elevated rates of electron transport and an enhanced NPQ capacity. We conclude that, in the absence of IM, green sectors develop morphological and biochemical adaptations that allow them to maximize photosynthesis to feed the white sectors, and to protect against photodamage.
The cotton fiber transcriptome
Authors: Wilkins Thea A. , Arpat A. Bulak
Published: August 2005

Among the longest cell types known in plants, cotton fibers are economically important seed trichomes that provide a unique single‐celled model system for studying fundamental biological processes. Functional genomic approaches have served to characterize dynamic changes to the cotton fiber transcriptome in response to developmental signals that control fiber morphogenesis at the level of a single cell. The genetic complexity of the fiber transcriptome is very high and accounts for as much as 45–50% of the genes in the cotton genome. In addition to a large diverse group of constitutively expressed genes, expression profiling of the transcriptome revealed two developmentally regulated stage‐specific expression patterns that define rapid cell elongation during primary cell wall (PCW) synthesis relative to secondary cell wall biogenesis. In developing cotton fibers, many fiber genes involved in PCW synthesis and turgor‐driven cell expansion are differentially expressed in a manner that parallels the growth rate. Characterization of the cotton fiber transcriptome has immediate applications in agricultural biotechnology and molecular breeding programs geared toward the genetic improvement of yield and fiber quality.
Photosynthesis is improved by exogenous glycinebetaine in salt‐stressed maize plants
Authors: Yang Xinghong , Lu Congming
Published: August 2005

The effects of exogenous application of glycinebetaine (GB) (10 mM) on growth, leaf water content, water use efficiency, photosynthetic gas exchange, and photosystem II photochemistry were investigated in maize plants subjected to salt stress (50 and 100 mM NaCl). Salt stress resulted in the decrease in growth and leaf relative water content as well as net photosynthesis and the apparent quantum yield of photosynthesis. Stomatal conductance, evaporation rate, and water use efficiency were decreased in salt‐stressed plants. Salt stress also caused a decrease in the actual efficiency of PSII (ΦPSII), the efficiency of excitation energy capture by open PSII reaction centers (Fv′/Fm′), and the coefficients of photochemical quenching (qP) but caused an increase in non‐photochemical quenching (NPQ). Salt stress showed no effects on the maximal efficiency of PSII photochemistry (Fv/Fm). On the other hand, in salt‐stressed plants, GB application improved growth, leaf water content, net photosynthesis, and the apparent quantum yield of photosynthesis. GB application also increased stomatal conductance, leaf evaporation rate, and water use efficiency. In addition, GB application increased ΦPSII, Fv′/Fm′, and qP but decreased NPQ. However, GB application showed no effects on Fv/Fm. These results suggest that photosynthesis was improved by GB application in salt‐stressed plants and such an improvement was associated with an improvement in stomatal conductance and the actual PSII efficiency.
Sustained accumulation of methyl salicylate alters antioxidant protection and reduces tolerance of holm oak to heat stress
Authors: Llusià Joan , Peñuelas Josep , Munné‐Bosch Sergi
Published: August 2005

Methyl salicylate (MeSA) is thought to have a major role in biotic and abiotic stresses by acting as a signal to trigger the oxidative burst, which is needed to activate gene expression in plant stress responses. To assess the potential effects of sustained foliar accumulation of MeSA on plant stress tolerance, the extent of photo‐ and antioxidant protection, lipid peroxidation and visual leaf area damage were evaluated in MeSA‐treated (c. 60 nl l−1 in air) and control holm oak (Quercus ilex L.) plants exposed to heat stress. Control plants showed an increase in foliar MeSA levels up to 1.8 nmol [gDW]−1 as temperature increased and they displayed tolerance to temperatures as high as 45°C, which might be attributed, at least in part, to enhanced xanthophyll de‐epoxidation and increases in ascorbate and α‐tocopherol. MeSA‐treated plants showed a sustained foliar accumulation of this compound, with values ranging from 10 to 23 nmol [gDW]−1 throughout the experiment. These plants showed lower ascorbate and tocopherol levels and higher oxidative damage at 50°C than controls, as indicated by enhanced malondialdehyde levels and leaf area damage and lower maximum efficiency of PSII photochemistry (Fv/Fm ratio). These results demonstrate that a sustained foliar accumulation of MeSA is detrimental to plant function and that it can reduce thermotolerance in holm oak by altering antioxidant defences.
Effect of sucrose on activity of starch synthesis enzymes in rice ears in culture
Authors: Sasaki Haruto , Edo Ei , Uehara Naoko , Ishimaru Tsutomu , Kawamitsu Yoshinobu , Suganuma Shihoko , Ueda Daisuke , Ohsugi Ryu
Published: August 2005

Grain filling of rice (Oryza sativa L.) is thought to be affected not only by the supply of carbohydrate from source organs, but also by sink activity, including the activities of enzymes related in starch synthesis. To examine the effect of translocated carbohydrate on sink activity, we cultured detached ears (cut 7 days after flowering) in a solution containing sucrose at various concentrations, glutamine and vitamins. Grain weights 16 days after the start of ear culture increased with increasing sucrose concentration up to 50–70 g sucrose l−1, but not above this range, probably because of low water potential. Activities of ADP glucose pyrophosphorylase, soluble starch synthase and sucrose synthase rapidly decreased in grains grown without sucrose, but increased with increasing sucrose concentration up to 50–70 g l−1. Expression of mRNAs for these enzymes and for sucrose transporter was also generally increased by sucrose at 50–70 g l−1. Though there was a good correlation between activity and expression of mRNA for sucrose synthase, the correlation for other enzymes was not very good. Thus, we suggested that the sink activity of grains in rice ears, and therefore the grain filling, was affected by the supply of carbohydrate from source organs, and that it was also owing to factors other than transcriptional regulation.
Photosynthetic performance of cold‐sensitive mutants of maize at low temperature
Authors: Pasini Luca , Bruschini Stefania , Bertoli Alessia , Mazza Raffaele , Fracheboud Yvan , Marocco Adriano
Published: August 2005

The virescent character is a genetic variant in pigmentation characterized by a delay in greening. Seedlings of thevirescentmutantsv1,v2,v3,v4,v13,v16,v18,v19 andv26 of maize exhibit chlorosis when grown at low temperature. Chlorotic leaves contain plastids that appear to have been arrested at an early stage of development. The results indicated thatV16,V2,V3 andV4 loci control early stages of chloroplast development whileV1,V13 andV19 may play a role at the end of development. The mutations in theV18 andV26 loci may control an intermediate step. At the pigment level, thevirescentmutants of maize differ widely from analogous mutations existing in other plants. The mutations were characterized by a reduced amount of chlorophyll a and b (up to 100 times inv16) and chlorophyll a/b ratio above normal (up to 13.7 inv16). Lutein content was reduced in all mutants (less than 3% inv16 compared to wild type) butv13, while pigments of the xanthophyll cycle were found at higher levels inv1 andv13 (more than 10 and 90%, respectively). Thev2,v3,v4,v16 andv18 mutants that are most depleted in β‐carotene (36 times less in average than wild type) are also deprived in D1 and D2 polypeptides. Moreover, thev2,v3,v4,v16 andv18 mutants characterized by a lower accumulation in lutein are most depleted of light‐harvesting complex II. All mutants possess a functioning, fully reversible, non‐photochemical quenching mechanism. This is most developed in thev13 andv19 mutants (φn = 0.48 and 0.44, respectively). These two mutants also have a relatively high primary photochemical yield for photosystem II and a functioning photosystem I (φp = 0.23 and 0.39, respectively). The most interesting mutant isv13 that shows severe chlorosis and possesses the most effective non‐photochemical quenching mechanism(s), which is thought to provide protection against excess photon absorption by photosystem II.
Role of transpiration from fruits in phloem transport and fruit growth in tomato fruits
Authors: Kawabata Saneyuki , Sasaki Haruka , Sakiyama Ryozo
Published: August 2005

Sink activity of fruits had been suggested to vary depending on transpiration of fruits. In this study, the effect of transpiration on dry matter accumulation was evaluated in tomato (Lycopersicon esculentum Mill.). Fruits of cv. Saturn at 14 days after anthesis were enclosed in chambers and aerated with dried (<15% RH) or moistened (>90% RH) air. These treatments did not cause any significant differences in fruit fresh weight, dry weight, percentage of dry matter, and concentration of soluble sugars within 5 days of the treatment, or the import of 14C within 18 h after the application of 14CO2 to the source leaves. However, displacement transducer measurement of each fruit showed a 40% reduction in growth rate in response to exchange of moistened air with dried air. When fruits of cv. Momotaro were exposed to transpiration treatments from the beginning of visible fruit enlargement until the ripening stage, the fruits exhibited 20% reduction in growth and lower accumulation of dry matter at harvest following treatment with dried air. These results suggested that higher transpiration reduced both water accumulation and dry matter accumulation. In contrast, when fruit growth was mechanically restricted by enclosing the fruits in a chamber packed with glass beads, and dried or moistened air was passed through the spaces between the glass beads, fruits exhibited higher dry matter accumulation under dried air treatment conditions. The results show that only under artificial conditions would transpiration of fruits potentially drive carbohydrate transport; it does not serve as a limiting step of carbohydrate transport to tomato fruits under normal circumstances.
The Normal Electrocardiogram of the Unanaesthetized Competition ‘Spanish Pouler’ Pigeon (Columba livia gutturosa)
Authors: Lopez Murcia M. M. , Bernal L. J. , Montes A. M. , Garcia Martinez J. D. , Ayala I.
Published: August 2005

This investigation was carried out on 64 healthy adult competition pigeons (Spanish Poulers) to determine reference values of electrocardiographic parameters in standard lead II; a comparative study between males and females was also performed to find changes in the electrocardiographic patterns related to sex. P wave was positive and monophasic; PR segment depression was present in 64% of records; the QRS pattern obtained was in most cases of the rS type, followed by the QS configuration. ST slurring (absence of ST) was observed in 47% of records and the mean electrical axis was in all cases negative. Statistically significant differences related to sex were found for P‐wave, R‐wave and T‐wave amplitudes, showing the males have greater amplitudes than females, associated with the increase of cardiac tissue mass. No sex‐related differences were found in heart rate and mean electrical axis.
Cytologic Features of Testicular Tumours in Dog
Authors: Masserdotti C. , Bonfanti U. , De Lorenzi D. , Tranquillo M. , Zanetti O.
Published: August 2005

In this paper, we report on our experience of cytology of fine needle biopsies performed on 92 dogs with testicular tumours during the period from 1998 to 2002. Cytological diagnosis was consistent with seminoma in 20 cases, sertolioma in 16 cases, Leydig cell tumours in 50 cases and mastocytoma in one case. Five cases could not be diagnosed by cytology. Cytological observations were confirmed after surgery by histopathological examination in 87 cases. Cytology provided a sensitivity of 95% for seminoma, 88% for sertolioma and 96% for Leydig cell tumours. The specificity was 100% for all three tumour types. In our experience cytology of fine needle aspirations of testicular tumours is a very reliable technique.
Persistent Truncus Arteriosus in a 6‐year‐old Cat
Authors: Nicolle A. P. , Tessier‐Vetzel D. , Begon E. , Sampedrano C. Carlos , Pouchelon J.‐L. , Chetboul V.
Published: August 2005

Truncus arteriosus (TA) was diagnosed in a 6‐year‐old neutered female domestic short‐haired cat by two‐dimensional and M‐mode echocardiography, colour flow imaging and spectral Doppler examinations. The lesion was characterized by a single large artery originating from the right ventricle. A single ascending aorta and a single pulmonary trunk arose from the common arterial trunk. The residual pulmonary trunk immediately split into left and right branches. The lesion was identified as a type I (TA). This case is of interest because it is the first reported echo‐Doppler description of such a malformation in felines, and because of the age of the cat at the time of diagnosis.
Characteristics of Acetaminophen Absorption in Healthy Unweaned Calves as an Indirect Measurement of the Oroduodenal Transit Rate of Liquid Meals
Authors: Schaer S. , Herrli‐Gygi M. , Kosmeas N. , Boschung H. , Steiner A.
Published: August 2005

Abomasal emptying plays an important role in the incidence of digestive problems in calves. Our aim was to evaluate the acetaminophen absorption test (APAT) for characterization of the oroduodenal transit (ODT) of liquid meals in unweaned calves. Six healthy, unweaned Simmental × Red Holstein crossbred calves were involved in the project. The study was performed in three blocks at 3, 6 and 9 weeks of the calves’ age. Within blocks, APAT was performed twice at an interval of at least 24 h. Once per each block, liquid transit was carried out with non‐coagulating electrolyte solution (NES). The second test within a block was performed either while atropine sulphate was administered (block I), or by feeding a coagulating milk replacer (block II), or by administration of NES by ruminal tube (block III). Data were compared within and among blocks. Significant differences of several APAT traits were present for the different types of feeding, the different types of meals, the administration of atropine sulphate and the different ages of the calves. The emptying indexTmax/Cmaxwas suggested to be a valuable kinetic parameter for the characterization of ODT in these calves. We conclude that APAT represents a valid technique for characterization of ODT of liquid meals in healthy unweaned calves and may be a valuable tool for the evaluation of the reticular groove mechanism, the abomasal emptying and the absorption capacity of the duodenum.
Electromyographical, Ultrasonographical and Morphological Modifications in Semitendinous Muscle after Transposition as Ventral Perineal Muscle Flap
Authors: Mortari A. C. , Rahal S. C. , Resende L. A. L. , Dal‐pai‐silva M. , Mamprim M. J. , Corrêa M. A. , Antunes S. H. S.
Published: August 2005

The aim of this study was to evaluate modifications occurring in semitendinous muscle after transposition as a ventral perineal muscle flap using electromyography, ultrasonography, and morphological studies. Ten male crossbreed dogs of 3–4 year old were used. The left semitendinous muscle was cut close to the popliteus lymph node, rotated and sutured at the perineal region. The contralateral muscle was considered as control. Motor nerve conduction studies of both sciatic‐tibial nerves, and electromyographic and ultrasonographic examinations of both semitendinous muscles were performed before surgery and 15, 30, 60, and 90 days postoperatively. Semitendinous muscle samples were collected for morphological analysis 90 days after surgery. No alterations were observed in clinical gait examinations, or in goniometrical and electroneuromyographical studies in pelvic limbs after surgery. Electromyography demonstrated that the transposed muscle was able to contract, but atrophy was detected by ultrasonography and morphological analysis.
Short‐term Effects on Pro‐inflammatory Cytokine, Lactoferrin and CD14 mRNA Expression Levels in Bovine Immunoseparated Milk and Blood Cells Treated by LPS
Authors: Prgomet C. , Sarikaya H. , Bruckmaier R. M. , Pfaffl M. W.
Published: August 2005

Leucocytes (WBC) are recruited from peripheral blood into milk as part of the inflammatory response, mediated through cytokines or interleukins (IL) synthesized by mammary tissue and the milk somatic cells (SC). The inflammatory response is related to the concentration of SC and the cytokines produced. To investigate and to compare the kinetics of cytokine production in SC and WBC during inflammation, cell culture models were established, where SC and WBC were cultured in parallel (n = 3). In addition, macrophages or monocytes were isolated from milk and blood with antibody‐coated magnetic beads and cultivated separately. Isolated cells were pure, unaltered and viable. Cultures were activated with 10 μg/ml lipopolysaccharide (LPS). After 0, 1, 2, 3, 4 and 8 h cells were harvested for RNA isolation. Cytokine [tumour necrosis factor alpha (TNFα), IL‐1β, IL‐6] mRNA expression responses and transcriptional activity of CD14 and lactoferrin (LF) were quantified via a one‐step real‐time RT‐PCR. Significant cytokine mRNA increases were found in all four cell culture types and genes, with peaks after 1 and 2 h (TNFα > IL‐6 > IL‐1β). In WBC or monocytes higher LPS responses and longer persistence could be found than in corresponding milk cells (IL‐1β > IL‐6 > TNFα). SC and macrophages are less responsive to LPS stimulation than WBC or monocytes. The strength of the immune response in the blood system is much more prominent than in the mammary gland. This may be ascribed to the role of CD14 on the cytokine production of the investigated cells, or may be caused by the blood‐to‐milk diapedesis. The constitutive transcription of CD14 mRNA in WBC and monocytes was found to be 6 to 15 times higher than in adequate milk cells.
Extracellular Matrix Compositon of the Equine Superficial Digital Flexor Tendon: Relationship with Age and Anatomical Site
Authors: Lin Y. L. , Brama P. A. J. , Kiers G. H. , Van Weeren P. R. , DeGroot J.
Published: August 2005

The objectives of the present study were to test the hypotheses that: (1) the composition of the extracellular matrix of the equine superficial digital flexor tendon (SDFT) shows great functional similarities with articular cartilage, i.e. that significant differences exist in biochemical composition of differently loaded areas (which in the case of tendons may be more apparent as tendon shows more obvious differences than cartilage); and (2) that, as in articular cartilage, no substantial alterations in biochemical composition take place during ageing once adulthood has been attained. Tendon samples were taken from 60 adult slaughter horses from a central area at cross‐section in the mid‐metacarpal region and at the height of the proximal sesamoid bones (sesamoid region) of the SDFT. Contents of collagenous and non‐collagenous components were determined. None of the parameters were correlated with age in either region, except for a significant increase in pentosidine cross‐links with age in the sesamoid region. Between the two anatomical regions, there were significant differences in all variables, except for hydroxylysylpyridinoline cross‐links. It was concluded that in the equine SDFT, similar to articular cartilage, most molecular parameters are not influenced by age in mature horses, indicating a low remodelling rate. Tendon composition is clearly different between regions, apparently reflecting different specific modes of biomechanical loading at the points sampled.
A Clinico‐pathological Study on the Effect of Vincristine on Transmissible Venereal Tumour in Dogs
Authors: Nak D. , Nak Y. , Cangul I. T. , Tuna B.
Published: August 2005

Transmissible venereal tumour (TVT) is a coitally transmitted neoplasm of dogs and is common among sexually active dogs, where sexual behaviour is not under control. Several treatment options are available for the treatment of the tumour, with chemotherapy being the most commonly employed. In this study, we investigated the clinical and cytological changes after weekly vincristine sulphate administration in 38 cases of naturally occurring TVT. Tumours totally regressed in 31 dogs after two to seven doses (mean 3.54 ± 1.01) of vincristine. One dog died after the fifth dose of vincristine, and in six dogs, an additional treatment with doxorubicin was needed. Masses were still present in four dogs and the histopathological examination revealed small nodules of granulation tissue in two dogs, while viable tumour cells were identified in the remaining two cases. No recurrences were observed in a follow‐up period of 7–49 months (mean 13.64 ± 9.66); in one dog, granulation tissue was detected in the surgery site after 2 months. Treatment success could easily be followed by the cytological changes. In conclusion, vincristine was found to be effective chemotherapeutic agent.
Pharmacokinetics, Urinary and Mammary Excretion of Ceftriaxone in Lactating Goats
Authors: Ismail M. M.
Published: August 2005

The pharmacokinetic properties of ceftriaxone were investigated in 10 goats following a single intravenous (i.v.) and intramuscular (i.m.) administration of 20 mg kg−1 body weight. After i.v. injection, ceftriaxone serum concentration–time curves were characteristic of a two‐compartment open model. The distribution and elimination half‐lives (t1/2α, t1/2β) were 0.12 and 1.44 h respectively. Following i.m. injection, peak serum concentration (Cmax) of 23.6 μg ml−1 was attained at 0.70 h. The absorption and elimination half‐lives (t1/2ab, t1/2el) were 0.138 and 1.65 h respectively. The systemic bioavailability of the i.m. administration (F %) was 85%. Following i.v. and i.m. administration, the drug was excreted in high concentrations in urine for 24 h post‐administration. The drug was detected at low concentrations in milk of lactating goats. A recommended dosage of 20 mg kg−1 injected i.m. every 12 h could be expected to provide a therapeutic serum concentration exceeding the minimal inhibitory concentrations for different susceptible pathogens.
Early Enteral Nutrition in Young Dogs Suffering from Haemorrhagic Gastroenteritis
Authors: Will K. , Nolte I. , Zentek J.
Published: August 2005

The purpose of this study was to investigate clinical and metabolic effects of combined parenteral and oral nutrition compared with parenteral nutrition in young dogs with haemorrhagic gastroenteritis in a prospective clinical study. Dogs with acute gastroenteritis received either parenteral nutrition (group PN,n = 9) or combined parenteral and early enteral nutrition (group EN,n = 10). Infusions were compounded from amino acids, lipids, glucose and electrolyte/glucose solutions [149 g/l glucose, 20 g/l triglycerides, 40 g/l amino acids and 4009 kJ metabolizable energy/l (957 kcal ME/l)], and supplemented with potassium, phosphate and trace elements. Group EN received additionally a hydrolysed diet (74 kJ/kg BW0.75on day 2 and 148 kJ/kg BW0.75on days 3 and 4). Glucose, triglycerides, protein, albumin, fibrinogen, urea, creatinine, alkaline phosphatase, glutamate dehydrogenase and glutamate pyruvate transaminase were measured before and during the infusions, haematological traits only before the infusions. Statistics included two‐factorialanovaand subsequentt‐test or Wilcoxon test (P < 0.05). All dogs of group EN survived compared with seven of nine patients in group PN. Most dogs in the EN group vomited within half an hour after introduction of oral feeding on day 2 but tolerance for food increased on days 3 and 4. The general health status and faecal and blood parameters of the surviving dogs were similar (P > 0.05) between the groups. In all dogs leucocytes increased during the treatment period, haematocrit and haemoglobin levels declined. Infusions increased blood glucose and triglycerides (P < 0.05); however, no adverse signs were observed. Early enteral nutrition was possible after a short period of adaptation, however, vomiting can be a severe problem. The evaluation of clinical benefits of early enteral nutrition in young dogs with haemorrhagic gastroenteritis requires further investigations.
The MAP kinase pathway mediates transcytosis induced by TNF‐α in anin vitroblood–brain barrier model
Authors: Miller Florence , Fenart Laurence , Landry Valérie , Coisne Caroline , Cecchelli Roméo , Dehouck Marie‐Pierre , Buée‐Scherrer Valérie
Published: August 2005

Cerebral capillary endothelial cells constitute the blood–brain barrier (BBB). In these highly specialized cells, transcellular transports rarely occur, and the presence of tight junctions between them leads to a low paracellular permeability. In order to understand the functions of this barrier, anin vitromodel of the BBB has been developed and consists in a co‐culture of primary cerebral capillary endothelial cells and glial cells. When these endothelial cells are subjected to an inflammatory agent, such as tumor necrosis factor‐alpha (TNF‐α),in vitroBBB permeability is increased, as indicated by the increase in holotransferrin transcytosis. However, no significant change in the paracellular permeability is observed. In order to understand the molecular mechanisms that underlie these transcytosis processes, we investigated the implication of the mitogen‐activated protein kinase (MAPK) signalling pathway, as TNF‐α is known to activate this kinase family. In the present study, an increase in the activation of p42–44 MAPK is observed after TNF‐α treatment. Holotransferrin transcytosis as well as p42–44 MAPK activation are inhibited after addition of a p42–44 MAPK pathway inhibitor (UO126) during TNF‐α challenge. These data suggest that the MAPK pathway is involved in the transcytosis regulation in endothelial cells from anin vitroBBB model.
Maximizing plant species inventory efficiency by means of remotely sensed spectral distances
Authors: Rocchini Duccio , Andreini Butini Sergio , Chiarucci Alessandro
Published: August 2005

Aim  Inventorying plant species in an area based on randomly placed quadrats can be quite inefficient. The aim of this paper is to test whether plant species richness can be inventoried more efficiently by means of a spectrally‐based ordering of sites to be sampled.

Location  The study area was a complex wetland ecosystem, the Lake Montepulciano Nature Reserve, central Italy. This is one of the most important wetland areas of central Italy because of the diverse plant communities and the seasonal avifauna.

Methods  Field sampling, based on a random stratified sampling design, was performed in June 2002. Plant species composition was recorded within sampling units of 100 m2 (plots) and 1 ha (macroplots). A QuickBird multispectral image of the same date was acquired and corrected both geometrically and radiometrically. Species accumulation curves based on spectral information were obtained by ordering sites to be sampled according to a maximum spectral distance criterion (i.e. by ordering sampling units based on the maximum distances among them in a four‐dimensional spectral space derived from the remotely sensed data). Different distance measures based on mean and maximum spectral distances among sampling units were tested. The performance of the species accumulation curve derived by the spectrally‐based ordering of sampling units was tested against a rarefaction curve obtained from the mean of 10,000 accumulation curves based on randomly ordered sampling units.

Results  The spectrally‐derived curve based on the maximum spectral distance among sampling units showed the most rapid accumulation of species, well above the rarefaction curve, at both the plot and the macroplot scales. Other ordering criteria of sampling units captured less richness over most of the species accumulation curves at both the spatial scales. The accumulation curves based on other measurements of distance were much closer to the random curve and did not show differences with respect to the species rarefaction curve based on random ordering of sampling units.

Main conclusions  The present investigation demonstrated that spectral‐based ordering of sites to be sampled can lead to the maximization of the efficiency of plant species inventories, an activity usually driven by the ‘botanist's internal algorithm’ (intuition), without any formalized rule to drive field sampling. The proposed approach can reduce costs of plant species inventorying through a more efficient allotment of time and sampling.
Working towards a European food information resource – EuroFIR
Authors: McKevith B.
Published: August 2005

Summary  Food information resources (food composition tables and electronic databases) are used by a range of different people including dietitians and other health professionals, food manufacturers and producers, and epidemiologists and other researchers.
New results from stable isotope studies show that folic acid should not be used as a reference folate for estimating relative absorptions of natural food folates
Authors: Wright A. J. A. , Finglas P. M.
Published: August 2005

Summary  An adequate supply of folate minimises the risk of neural tube defects, vascular disease (CHD, stroke) and possible cancers. Whilst the USA, Canada and Chile have a policy of mandatory fortification of white flour with folic acid, most countries of the EU do not permit the fortification of foodstuffs with folic acid. The UK allows folic acid fortification and in practice this has been mainly limited to some breakfast cereals and breads. Governments can only assess whether an optimal folate intake can be achieved through food sources alone if the proportion of food folate actually absorbed can be accurately established. Our recent use of stable‐isotope‐labelled folates has now questioned the reliability of experimental methods used for the past four decades to estimate the ‘relative absorption’ of food folates. Historically, the plasma 5‐methyltetrahydrofolic acid response to oral test doses of food folates are compared to the plasma response induced by a similar sized ‘reference’ dose of folic acid. We have found that a significant part of the plasma response does not actually originate from the test dose, and the accepted understanding of the initial site of biotransformation of folic acid upon which the experimental approach depends may be incorrect.
Dietary silicon and bone health
Authors: Sripanyakorn Supannee , Jugdaohsingh Ravin , Thompson Richard P. H. , Powell Jonathan J.
Published: August 2005

Summary  Silicon (Si) is the third most abundant trace element of the human body and is especially associated with connective tissues such as in bone, skin and blood vessels. Dietary Si is predominately derived from plant‐foods and, generally, is readily broken down and absorbed in the gastrointestinal tract in the form of orthosilicic acid. Cereals and cereal products (especially beer), green beans and some mineral water are examples of major dietary sources of Si. The majority of absorbed Si is then excreted in urine although some is taken up into tissues. Average Si intakes are around 25 mg/day in the Western World. In this review, dietary sources of Si, its metabolism and evidence for its biological role in bone health are presented.
Coeliac disease: an overview of the diagnosis, treatment and management
Authors: Mendoza N.
Published: August 2005

Summary  Coeliac disease is a common chronic disease in the UK and across Europe, affecting 1% of the population. Similar prevalence rates have also been reported elsewhere where cereals containing gluten are a staple in the diet. The symptoms are diverse and affect many organ systems of the body, not just the gastrointestinal tract. Blood tests have been developed to screen for coeliac disease but a small intestinal biopsy is required to confirm the diagnosis. Both tests require the patient to be following a gluten‐containing diet. Once diagnosed with coeliac disease the treatment is the gluten‐free diet, which must be adhered to for life, and involves removal of wheat, rye, barley (and derivatives of these cereals) from the diet. Some people with coeliac disease also avoid oats. Undiagnosed coeliac disease can increasee the risk of both malignant and non‐malignant complications, with gut lymphoma and osteoporosis being two of the most common complications; the risk of both is reduced by early diagnosis and strict adherence to the gluten‐free diet.
The Role of Competition in Determining Corporate Governance Outcomes: Lessons from Australia's Corporate Governance System
Authors: Dignam Alan
Published: August 2005

Successive waves of corporate collapse in every decade of Australia's history suggest that there is a significant unresolved corporate governance problem in Australia. Corporate collapse has been followed by reform but with little effect on the overall pattern of collapse and reform every decade. This article suggests that one of the elements which entrenches corporate governance problems in Australia is the competitive environment in which companies operate, which currently is not regulating management. It is argued that this anti‐competitive environment has two significant effects. First, key shareholders have retained controlling blocks of shares as the benefits of control and the costs of unconstrained management are high in such distorted markets. Secondly, management skills have stagnated, so that bad management and regular management failure have become features of the corporate governance system.
Regional Cerebral Hemodynamics During Migraine and Cluster Headaches Measured by the 133Xe Inhalation Method
Authors: Sakai Fumihiko , Meyer John Stirling
Published: August 2005

SYNOPSIS

Measurements of noninvasive regional cerebral blood flow (rCBF) were made by the 133Xe inhalation method in 71 patients with different types of headache and 32 age matched normal controls. Flow gray (Fg) was calculated by two compartmental analysis from the x‐ray subtracted gamma curves, and extracerebral flow indices (EFI) were calculated as an estimate of the percentage contribution by extracerebral tissues.During the headache phase, mean Fg in a group (N = 13) with classic and common migraine was significantly higher compared to a comparable group (N = 12) measured in the headache‐free interval. Serial measurement made during progression in the severity of the migraine headaches showed accompanying increases in the mean Fg as the headache worsened. In 24 patients with severe migraine studied 2‐48 hours after the headache subsided, the mean Fg values remained significantly increased during this immediate post‐headache interval compared with patients who were headache‐free for six days or longer. Serial measurements made during and after the headache showed progressive reduction of mean Fg values to normal within six days after the headache subsided. Marked cerebral dysauto‐regulation was present during the migraine headache and showed progressive recovery as the headache subsided. Reduction of the head pain by administration of codeine decreased hemispheric Fg values but did not change the high flows in the basilar artery territory. Conversely, administration of ergotamine did not change hemispheric Fg values but reduced rCBF in brain stem‐cerebellar regions. Significant regional reductions of Fg correlating with the neurological deficit was measured during the prodrome of classic migraine and during the headache and post‐headache intervals of complicated migraine. During cluster headaches, mean Fg values were also significantly increased and the extracerebral flow indices showed marked increases with highest values recorded at the site of the headache. It was concluded that cerebral hyperperfusion during migraine headaches is mainly due to post‐ischemic reactive hyperemia but may be compounded by functional hyperemia due to the head pain itself.
Systemic Non‐Organic Central Pain: A New Syndrome with Decentralization Supersensitivity
Authors: Sicuteri F. , Anselmi B. , Del Bianco P.L.
Published: August 2005

SYNOPSIS

Some systemic painful syndromes are often unclassifiable because of their unconvincing clinical features and often labelled as hysterical, psychogenic or atypical manifestations of fibrositis or rheumatism. Some of these are grouped in a new syndrome called systemic "non‐organic central pain (NOCP)". The most salient features of systemic NOCP are: a) diffused pain subsequent to and accompanying idiopathic headache, b) characteristics of pain similar to, if less pronounced, than organic central pain of the thalamic syndrome and c) decentralization supersensitivity to monamines. Systemic NOCP was diagnosed in 14 patients admitted to the hospital for serious disabling systemic pains. In 7 of these, an impressive increase of vein sensitivity to noradrenaline, dopamine, tyramine, and even more so to 5‐HT (up to 1000 times), was detected. Because this supersensitivity involves different monamines, it should be considered a decentralization process. This decentralization supersensitivity is related to the mechanism of pain and is hypothesized as a non‐organic, biochemical, usually genetic impairment of the antinociceptive system. Migraine, tensional and other idiopathic headaches are more commonly considered expressions of NOCP. The clinical importance of NOCP is emphasized by its high neuroticizing capacity as is commonly seen in other chronic, recurrent pain disorders.
An Epidemiological Study of Headache In an Urban and a Rural Population In Northern Finland
Authors: Nikiforow Rita , Hokkanen E.
Published: August 2005

SYNOPSIS

Information on the prevalence of headache and its characteristic features and the factor provoking it was collected using a questionnaire similar to that introduced by Waters. The questionnaire was posted to every inhabitant over 15 years of age in a defined urban and a defined rural area in northern Finland. The reliability of the questionnaire was tested by neurological examination of a random sample of 200 persons. The response rate was 74.0% in the urban and 79.5% in the rural area, a total of 3067 questionnaires being returned. The prevalence of headache in the year preceeding the survey was 73.1% in women and 57.6% in men. This difference was significant. At the same time the prevalence was slightly higher in the urban than in the rural area. The percentage with headache was highest between 15 and 64 years of age in both the urban and the rural men and women, and declined sharply after 65 years of age. Only in men aged 15‐24 years was it significantly more common in the urban area. Education, social class and mode of employment did not influence the prevalence of headache once pensioners were excluded. Headache was slightly more common in urban self‐employed people and in urban employees, but equally common in urban and rural students, housewives and pensioners. It was significantly more common in married men and women. The percentage of women with headaches related to the menstrual period was low. The most common provoking factor was stress, the sauna‐bath ranking second. No correlation was found between smoking habits and headache in this survey.
Headache and Sex Hormone Therapy
Authors: Dennerstein Lorraine , Laby Betty , Burrows Graham D. , Hyman Graeme J.
Published: August 2005

SYNOPSIS

A review of the literature suggested that falling levels of estrogen may trigger headaches for many women. A double blind controlled cross‐over study was carried out on 49 women, all of whom had undergone a surgical menopause. During the study each woman was randomly allocated each of the following drugs daily for three months: ethinyl estradiol 50 μg; d norgestrel 250 μg; combination of ethinyl estradiol 50 μg and d norgestrel 250 μg; and placebo. Women who reported they were headache free sufferers in the past had higher neuroticism and lower extraversion scores than others. Women who suffered headaches during a hormone free time interval had significantly higher plasma testosterone levels. An increase in the frequency of headaches occurred in association with a fall in estrogen content of the medication.
Vascular Headaches in Mixed Connective Tissue Disease
Authors: Bronshvag Michael M. , Prystowsky Stephen D. , Traviesa Daniel C.
Published: August 2005

SYNOPSIS

A prospective study of 46 patients with mixed connective tissue disease (MCTD) revealed that 16 (35%) had recurrent, vascular headaches. Detailed neurologic evaluation of 12 headache patients available for further study revealed the following: 3 had lateralized, throbbing headaches; 9 had bilateral headaches; 8 patients experienced prodromal symptoms (7 had visual auras); and 3 experienced nausea or vomiting. Only 1 patient described headache as interfering with daily activities, and no patients were prostrated. Only 1 patient had frequently required narcotic (codeine) therapy, and none were employing ergot. Headache symptoms have persisted in 8 patients; 5 of these 8 suffer at least 1 headache per week. It appears that frequent vascular headache of mild to moderate severity is a relatively common symptom in MCTD.
Levotryptophan Treatment in Migraine
Authors: Kangasniemi P. , Falck B. , Långvik Vivi‐Ann , Hyyppä M.T.
Published: August 2005

SYNOPSIS

In order to assess whether an increased brain serotonin tone prevents migraine symptoms, eight migraine patients were treated with levotryptophan in the controlled trial. Plasma and lumbar CSF were collected approximately one hour after the last dose of amino acid on the second week during the headache‐free interval. Samples were also taken 4 hours after the onset of the headache attack. Visual evoked cortical potentials were recorded one hour after the ingestion of 500 mg of levotryptophan.In four of the eight migraine patients, headache indices were markedly lower during typptophan treatment than during placebo (levoleucine) treatment. Levotryptophan caused an elevation of plasma free and total tryptophan, and CSF‐tryptophan from their basal values obtained during placebo treatment. Therefore levotryptophan may be a worthwhile alternative for a selective and still incompletely characterized group of migraine patients.
Specific and Non‐specific Effects of Skin Temperature Control in Migraine Management
Authors: Largen John W. , Mathew Roy J. , Dobbins Ken , Claghorn James L.
Published: August 2005

SYNOPSIS

Skin temperature self‐regulation has been demonstrated to be an efficacious behavioral technique in the management of migraine headache. However, a controversy has arisen over the particular significance of the skin temperature factor per se. The present pilot study represents an attempt to evaluate the relative contributions of specific and non‐specific effects of thermal biofeedback in migraine therapy. Thirteen female migraine patients were randomly assigned to either a “hand‐warming”or a “hand‐cooling” treatment condition. The pretreatment baseline was compared to the post‐training follow‐up period along seven indices of headache activity. Results indicated that primarily non‐specific factors and to a lesser extent, specific temperature factors contribute to the therapeutic gains observed in migraine therapy.
A Double‐blind Study of Zomepirac Sodium and Placebo in the Treatment of Muscle Contraction Headache
Authors: Diamond Seymour , Medina Jose L.
Published: August 2005

SYNOPSIS

In a double‐blind parallel study zomepirac sodium was compared with placebo in the treatment of muscle‐contraction headache. Eighty patients with histories of recurrent muscle‐contraction headaches were given either zomepirac 100 mg, zomepirac 50 mg, or placebo. Patients submitted evaluations for pain relief and analgesic acceptability over a range of four headache episodes. In addition, global evaluations were made by the patients and by the investigator.

In the first headache episode zomepirac sodium 100 mg was significantly superior to placebo in pain relief (p = 0.030), and in analgesic acceptability (p = 0.006). Average values across all episodes indicated a significant linear dose response for zomepirac in analgesic acceptability (p<0.05). Global evaluations showed zomepirac sodium 100 mg to be significantly superior to placebo (p<0.05). The incidence of adverse effects did not vary significantly among treatment groups.

Results of the study suggest that zomepirac sodium will be a useful non‐narcotic agent in the treatment of recurrent muscle‐contraction headaches requiring the use of a prescription analgesic.