bluuebunny/crossref_metadata_2025 huggingface dataset:
Stress‐Specific Opioid Modulation Of Haemodynamic Counter‐Regulation
Authors: Molina Patricia E
Published: March 2003

1. The haemodynamic and cardiovascular responses to stress, in addition to being under control of the autonomic nervous system, are also under opiate modulation. Our studies have provided evidence for activation of the endogenous opioid system in haemorrhagic shock, sepsis and trauma. Furthermore, we have demonstrated that both central and systemic opiate administration to naïve rats result in marked alterations in haemodynamic responses, which are associated with activation of the sympathetic nervous system.

2. Because of the ubiquitous presence of opiate receptors in both the central nervous system and peripheral tissues, as well as their production and release centrally and peripherally, this facilitates an endocrine as well as a paracrine contribution to modulating vascular responses to stress, either directly or indirectly. Results from previous studies suggest that endogenous opioids are not involved in mediating the lipopolysacharide‐induced hypotensive response.

3. In more recent studies, we have examined the role of opiate receptor activation in modulating the haemodynamic and neuroendocrine responses to fixed pressure haemorrhagic shock in conscious unrestrained rats. Using systemic opiate blockade (naltrexone, 15 mg/kg, i.p.) prior to haemorrhage, we have observed that blood loss required to achieve mean arterial blood pressure of 40 mmHg was higher in naltrexone‐treated animals than in time‐matched saline controls. Interestingly, the haemodynamic modulation exerted by naltrexone cannot be attributed to differences in circulating catecholamine levels. Haemorrhage produced an immediate and progressive increase in circulating adrenaline and noradrenaline levels, reaching values that were 50‐ and 20‐fold higher than basal, respectively. Naltrexone pretreatment did not alter the time‐course or magnitude of the rise in circulating levels of catecholamines.

4. These results indicate that endogenous opioid activation contributes to the haemodynamic dishomeostasis associated with blood loss. Our findings suggest stress‐specific roles for opiate‐sensitive haemodynamic counter‐regulatory responses.
Nitric Oxide In Mesenteric Vascular Reactivity: A Comparison Between Rats With Normotension And Hypertension
Authors: Chang Huai‐Ren , Lee Ru Ping , Wu Chia Yen , Chen Hsing I
Published: March 2003

1. Nitric oxide (NO) plays an important role in various physiological functions. The continuous formation of endogenous NO from endothelial cells maintains a vasodilator tone and regulates blood flow and pressure. However, the role of NO in hypertension remains controversial.

2. In the present study, we used an in situ mesenteric perfusion system. The primary objectives of the study were to examine whether or not mesenteric vasoreactivity is changed by alterations in perfusion pressure and to assess the role of NO in changes of vascular reactivity in hypertension.

3. Spontaneously hypertensive rats (SHR; 12–15 weeks of age) and age‐matched normotensive Wistar‐Kyoto (WKY) rats were used as the experimental and control groups, respectively. Endothelium‐dependent and ‐independent vasodilation was detected by acetylcholine (ACh) or NO donors (sodium nitroprusside (SNP) and S‐nitroso‐N‐acetylpenicillamine
(SNAP)). Dose‐dependent reactivity to these agents (10–6 to 10–4
mol/L) was detected by bolus intra‐arterial injections of 10 μL of the
test agents at 5 min intervals. Dose‐dependent responses to vasoconstrictor drugs,
such as noradrenaline (NA) and phenylephrine (PE; 10–6 to 10–4
mol/L) were also observed. The NO synthase inhibitor NG‐nitro‐L‐arginine
methyl ester (L‐NAME; 10 mg/kg) was given to examine the contribution of NO to the vasoreactivity of the mesenteric bed.

4. Acetylcholine, SNP and SNAP produced dose‐dependent vasodilation in both WKY rats and SHR. The magnitude of the vasodilation was significantly greater in SHR than in WKY rats. It was also greater at high than low flow rates in SHR. The increase in mesenteric perfusion pressure following L‐NAME was significantly
higher in SHR than in WKY rats. However, there were no differences in responses to
L‐NAME between low and high flow rates in SHR. Endothelium‐independent vasoconstriction (NA and PE) was dose dependent in both SHR and WKY rats. The magnitude of the endothelium‐independent vasoconstriction was greater in SHR than in WKY rats.

5. The results suggest that endothelium‐dependent or ‐independent mesenteric vasoconstriction and vasodilation is enhanced in SHR compared with WKY rats, supporting the concept of enhancement of NO function in the hypertensive state. Flow‐induced shear stress is also a key factor in the regulation of peripheral resistance depending on NO formation in hypertension.
Weight Reduction Decreases Soluble Cellular Adhesion Molecules In Obese Women
Authors: Ito Hiroyuki , Ohshima Akiko , Inoue Misako , Ohto Naoko , Nakasuga Kazuta , Kaji Yoshikazu , Maruyama Toru , Nishioka Kazuo
Published: March 2003

1. Obesity is known to increase the risk for atherosclerotic diseases. Serum levels of cellular adhesion molecules are reported to be indices of atherosclerosis. The aim of the present study was to assess the effect of weight reduction on soluble intercellular adhesion molecule‐1 (sICAM‐1) and soluble E‐selectin (sE‐selectin).

2. Eighteen non‐diabetic normotensive obese women participated in a 3 month lifestyle‐modification programme (intervention group). The programme consisted of lectures on diet, exercise sessions and behavioural modification by weight charting. Fourteen women who did not enter the programme served as controls. Body fat mass (FM) was measured by dual‐energy X‐ray absorptiometry. Soluble ICAM‐1 and sE‐selectin were measured by ELISA.

3. After 3 months, sICAM‐1 and sE‐selectin, as well as body FM, decreased in the intervention group (P < 0.001), while no changes were observed in the control group. The baseline sE‐selectin was positively correlated with total body FM, trunk FM and percentage body fat (r = 0.50–0.57; P < 0.01), but not with leg FM. The change in sE‐selectin was also correlated with changes in total body FM and trunk FM (both r = 0.46; P < 0.01). Baseline sICAM‐1 was not significantly correlated with these variables. The associations between changes in sICAM‐1 and changes in total body FM or trunk FM were of borderline significance (both r = 0.34; P = 0.06). Linear regression analysis indicated that the change in sE‐selectin was explained by the change in trunk FM (R2 = 0.18; P < 0.01).

4. Soluble ICAM‐1 and sE‐selectin were positively correlated with obesity, especially with central obesity. Weight reduction resulted in decreases in soluble adhesion molecules, which may suggest a downregulation of endothelial activation.
Mode‐dependent inhibition by quinidine of Na+–Ca2+ exchanger current from guinea‐pig isolated ventricular myocytes
Authors: Zhang YH , Hancox JC
Published: March 2003

1. The aim of the present study was to determine whether or not the class Ia anti‐arrhythmic agent quinidine modulates ionic current (INaCa) generated by the sarcolemmal Na+–Ca2+ exchanger of adult ventricular cardiac myocytes.

2. Selective whole‐cell voltage‐clamp recordings of INaCa were made from guinea‐pig ventricular myocytes, with major interfering currents blocked. The INaCa was measured as the ionic current sensitive to 10 mmol/L external Ni2+ during a descending voltage ramp protocol.

3. The effects of quinidine concentrations in the range 10–100 μmol/L were studied. Quinidine produced a concentration‐dependent partial blockade of outward INaCa, generated by reverse‐mode exchange. At +60 mV, 100 μmol/L quinidine blocked INaCa by 33.0 ± 4.1% (mean±SEM; n = 4). This was the maximal concentration that we were able to test, because concentrations of quinidine higher than 100 μmol/L were found to be toxic to cells under our conditions. The drug did not produce any significant inhibition of inward INaCa (generated by forward‐mode exchange).

4. The Ni2+‐insensitive residual current was not significantly altered by quinidine at any membrane potential, confirming that the inhibitory effects of quinidine we observed could be attributed to an action on the Na+–Ca2+ exchanger.

5. For the purpose of comparison, quinidine was tested against L‐type Ca current (ICa,L). It blocked peak ICa,L at 0 mV, with an IC50 of 14.9 ± 1.5 μmol/L. Thus, quinidine was less potent against the exchanger than against ICa,L.

6. Our data suggest that quinidine preferentially inhibits the Naout/Cain mode of exchanger function. We conclude that this drug is a weak inhibitor of ventricular INaCa and that the inhibitory effect is mode dependent.
Human vascular endothelial growth factor B: Characterization of recombinant isoforms and generation of neutralizing monoclonal antibodies
Authors: Scotney PD , MacKenzie A , Maccarone P , Fabri LJ , Scrofani SDB , Gooley PR , Nash AD
Published: March 2003

1. The vascular endothelial growth factor (VEGF) family is a focus of interest with respect to novel therapies for cardiovascular disease. Members of this family bind differentially to three receptor tyrosine kinases, namely VEGF‐R1, ‐R2 and ‐R3, and to the semaphorin receptors neuropilin 1 and 2. The role of VEGF‐R1 and the factors that interact exclusively with this receptor (VEGF‐B and placenta growth factor) has remained controversial.

2. To further elucidate the role of VEGF‐B in blood vessel formation and function, we have expressed, purified and refolded both naturally occurring VEGF‐B isoforms and a truncated amino acid 10–108 form. All refolded proteins have been demonstrated to bind to VEGF‐R1 with appropriate kinetics in biosensor‐based analysis.

3. Robust cell assays for VEGF‐R1 ligands, such as VEGF‐B, have been problematic. We have developed an assay based on a chimeric receptor consisting of extracellular domains 1–4 of VEGF‐R1 and the transmembrane and intracellular domains of gp130. The cell line expresses luciferase to high levels 24 h after exposure to VEGF‐A and both refolded VEGF‐B167 and the short 10–108 isoform have been demonstrated to be active in this assay.

4. The novel cell‐based assay, in combination with a variety of immunochemical approaches, has been used to identify and characterize monoclonal antibodies that neutralize VEGF‐B activity.
Characterization and expression of embryonic globin in the rainbow trout, Oncorhynchus mykiss: Intra‐embryonic initiation of erythropoiesis
Authors: Maruyama Kouichi , Yasumasu Shigeki , Iuchi Ichiro
Published: March 2003

When fractionated by reverse‐phase high performance liquid chromatography (HPLC), the embryonic hemoglobin of the rainbow trout, Oncorhynchus mykiss, consisted of eight globins different from adult globins in terms of retention time. Amino acid sequences of the N‐terminal regions of some globins were determined. In addition, four cDNA clones for embryonic globins from 10‐day embryos were isolated (at 15°C), sequenced and the amino acid sequences predicted. In comparison with the sequences of previously characterized globins, they corresponded to two α‐type and two β‐type globins and therefore were named em.α‐1, em.α‐2, em.β‐1 and em.β‐2. The N‐terminal 36 amino acids of one (E2) of the embryonic globins isolated by HPLC were identical to those of the sequence deduced from a cDNA, em.β‐2. The phylogenetic relationship between the embryonic globins and other globins previously reported was discussed. The present study is the first demonstration of amino acid sequences of embryonic globins in a teleost. To understand the initiation of erythropoiesis in the early development of the rainbow trout, histochemistry using o‐dianisidine/hydrogen peroxide, immunohistochemistry using an antibody against embryonic hemoglobin, and northern blotting and whole embryo in situ hybridization using antisense RNA probe for em.β‐2 were performed. Embryonic globin mRNA, globin and hemoglobin appeared first in the anterior part of the intermediate cell mass (ICM) located in the median line beneath the notochord of embryos 6–7 days after fertilization at 15°C (Vernier’s stages 16–20). Shortly after that, the expression signal extended to the posterior part of the ICM and spread out laterally to blood islands on the posterior yolk sac. Thus, the initiation of erythropoiesis in the early embryo of rainbow trout is intra‐ embryonic.
Rapid and selective removal of larval erythrocytes from systemic circulation during metamorphosis of the bullfrog, Rana catesbeiana
Authors: Hasebe Takashi , Oshima Hiroyuki , Kawamura Kosuke , Kikuyama Sakae
Published: March 2003

Mechanisms of hemoglobin transition during bullfrog metamorphosis were investigated by labeling red blood cells from larvae (L‐RBC) and from froglets (A‐RBC) with a fluorescent dye, PKH26. The life span of the labeled L‐RBC in systemic circulation was significantly shorter when they were injected into the animals at the metamorphic climax, compared to injection into pre‐ or postmetamorphic animals. The A‐RBC had a long life span regardless of the metamorphic stage of the recipient animal. Therefore, L‐RBC were selectively removed from the systemic circulation at the time of metamorphic climax. During climax, the labeled L‐RBC were ingested by hepatic and splenic macrophages, indicating that macrophages are involved in the specific elimination of L‐RBC.
Differentiation of the gonad rudiment into ovary and testis in the solitary ascidian, Ciona intestinalis
Authors: Okada Toshiaki , Yamamoto Masamichi
Published: March 2003

In the early juveniles of Ciona intestinalis, primordial germ cells arise on the degenerated mass of the resorbed tadpole tail, and assemble to form a discrete gonad rudiment. The present study elucidated the morphological sequences during differentiation of the gonad rudiment into the testis and ovary. In 11‐ to 12‐day juveniles, the gonad rudiment, an elongate sac, divided into the testicular and ovarian rudiments. The testicular rudiment separated as a round vesicle from the thickened wall of the elongate sac. The original sac, after separation of the round vesicle, developed into the ovary. In the testicular rudiment, germ cells formed a continuous central mass without association of somatic cells, while in the ovarian rudiment, each germ cell was associated with somatic cells within the epithelium composing the wall of the rudiment. In 13‐ to 15‐day juveniles the testicular rudiment changed into branched tubes ending in club‐shaped follicles. Cells characterized by many flattened cisternae of rough endoplasmic reticulum (distal cells) constituted the distal wall of each follicle. Spermatogenic cells were freely present in the follicular lumen, but the largest spermatogonia were in contact with the distal cells. Both in the testicular and ovarian rudiments, germ cells entered meiosis in 18‐day juveniles. A novel body (periesophageal body) was found just beneath the ventral margin of the esophageal opening. It comprised irregular follicles made up of one cell type whose cytoplasm, filled with round vesicles and Golgi complexes, was suggestive of an endocrine function. Fragments derived from the periesophageal body were present around the developing ovary.
Misexpression of genes in brain vesicles by in ovo electroporation
Authors: Nakamura Harukazu , Watanabe Yuji , Funahashi Jun‐ichi
Published: March 2003

Transfection to living chick embryos in ovo by electroporation has been recently developed. In this mini‐review, misexpression in brain vesicles is introduced. To transfect, expression plasmid is inserted in the brain vesicle, and the square pulse of 25 V, 50 ms was charged five times. The translation product of the transfected gene is detected 2 h after electroporation, and reaches the peak at 24 h after electroporation. Transfection is so effective that this method is contributing greatly to the study of the molecular mechanisms of morphogenesis.
Ectoderm exerts the driving force for gastrulation in the sand dollar Scaphechinus mirabilis
Authors: Takata Hiromi , Kominami Tetsuya
Published: March 2003

How the ectodermal layer relates to the invagination processes was examined in the sand dollar Scaphechinus mirabilis. When the turgor pressure of blastocoele was increased, invagination was completely blocked. In contrast, an increase in turgor pressure did not affect elongation of the gut rudiment in the regular echinoid Hemicentrotus pulcherrimus. Rhodamine–phalloidin staining showed that the distribution of actin filaments was different between two species of embryos. In S. mirabilis gastrulating embryos, abundant actin filaments were seen at the basal cortex of ectoderm in addition to archenteron cells, while the intense signal was restricted to the archenteron in H. pulcherrimus. To investigate whether actin filaments contained in the ectodermal layer exert the force of invagination, a small part of the ectodermal layer was aspirated with a micropipette. If S. mirabilis embryos were aspirated from the onset of gastrulation, invagination did not occur at all, irrespective of the suction site. Even after the archenteron had invaginated to one‐half of its full length, further elongation of the archenteron was severely blocked by suction of the lateral ectoderm. In contrast, suction of the ectodermal layer did not affect the elongation processes in H. pulcherrimus. These results strongly suggest that the ectodermal layer, especially in the vegetal half, exerts the driving force of invagination in S. mirabilis.
Abnormal formation of sarcoplasmic reticulum networks and triads during early development of skeletal muscle cells in mitsugumin29‐deficient mice
Authors: Komazaki Shinji , Nishi Miyuki , Takeshima Hiroshi , Nakamura Hiroaki
Published: March 2003

Recently, we detected a novel membrane protein, mitsugumin29 (MG29), in the triads in rabbit skeletal muscle cells and suggested important roles for this membrane protein in the formation of the sarcoplasmic reticulum (SR) networks and triads in muscle cells. In the present study, we examined the development of skeletal muscle cells in MG29‐deficient mice to try to determine the roles played by MG29 in the formation of the SR networks and triads. Ultrastructural observations revealed some morphological abnormalities in these mice, such as incomplete formation of the SR networks, an irregular running of the transverse tubule and a partial defect in the triads at the A‐I junctional region. These ultrastructural abnormalities occurred during early myogenesis and were preserved until the adult stage. The possible roles for MG29 in the formation of SR networks and triads in skeletal muscle cells are discussed in the light of these observations.
Identification and characterization of a unique Xenopus laevis egg envelope component, ZPD
Authors: Lindsay LeAnn L. , Yang Joy C. , Hedrick Jerry L.
Published: March 2003

We report the identification of a previously undetected Xenopus laevis egg envelope component discovered through cloning experiments. A cDNA sequence was found that represented a mature protein of 32 kDa. Peptide antibodies were generated to probe for the protein in egg envelope samples and reactivity was found to a glycoprotein of approximately 80 kDa. When deglycosylated egg envelope samples were probed, a 32 kDa protein was labeled, confirming the size of the translated cDNA sequence. A BLAST analysis showed that it is most closely related (34% amino acid identity) to the ZP domains of mammalian tectorin, uromodulin and ZPA. From a dendrogram of known egg envelope glycoproteins, the new glycoprotein was shown to be unique among egg envelope components and was designated ZPD. A similar glycoprotein was identified by immunocrossreactivity in Xenopus tropicalis and Xenopus borealis egg envelopes.
Nutrient dynamics and lignocellulose degradation in decomposingQuercus serrataleaf litter
Authors: Salamanca Eric F. , Kaneko Nobuhiro , Katagiri Shigeo , Nagayama Yasuhide
Published: March 2003

The litter mass loss, concentration and mass of some major nutrient elements, degradation of lignin and cellulose in decomposingQuercus serrataMurray leaf litter were monitored for 3 years using the litterbag method. The mobility of elements during the course of the study was in the order of: K > P > C > Mg > Ca > N. Three patterns of nutrient dynamics were observed: (i) concentration increased while mass decreased (N, Mg and Ca); (ii) concentration and nutrient mass decreased (K and C); and (iii) both concentration and mass had fluctuated (P). The C to element ratio tended to increase as the element was released, and decreased as the element was retained. Nitrogen mobility in relation to carbon was characterized by three phases: (i) initial release; (ii) accumulation and (iii) final release. The decay rate (k) calculated from 0–6 months period was overestimated for an average annual rate while those of 0–36 months fit the negative single exponential model (Adj.r2 = 0.99) better than shorter periods. For lignin, the concentration had increased then decreased but tended to stabilize after 1 year while the lignin mass had continuously decreased throughout the study period. During the first 9 months, both the concentrations and mass of cellulose had fluctuated but declined thereafter. The amounts of N had initially increased but declined after 1 year; P had fluctuated while K, Ca, Mg and C had decreased throughout the study. N and C/N ratio exerted strong influence on mass loss during the first24 months but the influence of lignin emerged after 24 months.
Satellite tracking of the migration of the red‐crowned crane Grus japonensis
Authors: Higuchi Hiroyoshi , Shibaev Yuri , Minton Jason , Ozaki Kiyoaki , Surmach Sergey , Fujita Go , Momose Kunikazu , Momose Yuria , Ueta Mutsuyuki , Andronov Vladimir , Mita Nagahisa , Kanai Yutaka
Published: March 2003

Autumn migration routes of red‐crowned cranes, Grus japonensis, from two continental east Asian sites were documented in detail by satellite tracking. Two routes were identified: a 2200 km western route from Russia's Khingansky Nature Reserve to coastal Jiangsu Province, China; and a 900 km eastern route from Lake Khanka (Russia) to the Korean Peninsula and the Demilitarized Zone. The most important rest‐sites were identified as Panjin Marsh (China), coastal mudflats south‐east of Tangshan City (China), the Yellow River mouth (China), Tumen River mouth (North Korea/China/Russia), Kumya (North Korea) and Cholwon (Korean DMZ). Movements within the wintering range were also recorded, including complex commuting between sites by individual cranes and patterns of daily movements within sites. These data should prove useful for conservation of the flyway.
Effects of seed aggregation on the removal rates of elaiosome‐bearingChelidonium majusandViola odourataseeds carried byFormica polyctenaants
Authors: Gorb Elena , Gorb Stanislav
Published: March 2003

In a field dominated byFormica polyctenaFoerst. ants, we examined the effect of seed aggregation on the seed‐removal rates of two plant species: a large‐seeded obligate myrmecochoreViola odorataL. and a small‐seeded diplochoreChelidonium majusL., which was autochorous as well as myrmecochorous. The effect was statistically non‐significant inV. odoratabut significant inC. majus, with more closely aggregated seeds having higher removal rates. The large seeds of the obligate myrmecochore were more quickly discovered and repeatedly removed by ant workers than were the small seeds of the diplochore.
Interspecific variation and ontogenetic change in antiherbivore defense in myrmecophytic Macaranga species
Authors: Itino Takao , Itioka Takao
Published: March 2003

The present study examined whether or not coexisting congeneric plant species have different defense strategies against herbivores, and the intensity of defense changes ontogenetically. We focused on nine myrmecophytic Macaranga species and estimated the intensity of non‐biotic and biotic defense by the degree of leaf damage in ant‐free and ant‐occupied plants, respectively. Ant colonization of myrmecophytic Macaranga species occurred in the early stage of plant development (5–50 cm‐tall seedlings). Following the colonization, damage by leaf eaters was minimized and stable during the ontogenetic development of the host plants due to protection by ants. In ant‐free trees, however, herbivore damage was immense in seedlings and decreased as trees grew. Interspecific comparison of leaf damage and herbivore fauna supported that coexisting congeneric plants differ in their types of non‐biotic (chemical/structural) defense: without ant protection, Macaranga beccariana, for example, was somewhat resistant to leaf eaters but susceptible to gall‐makers, Macaranga trachyphylla was heavily infested by generalist leaf eaters, and Macaranga winkleri was exploited by ant‐predatory birds. Despite these variations in chemical/structural defense, ant‐colonized plants were generally well defended by ants against all kinds of herbivores. This suggests that the individual host‐specific ant mutualists are well adapted to deter the chemically or structurally adapted herbivores. These results imply that in the history of diversification in the Macaranga–ant–herbivore system, a sequence of mutual counter adaptation took place not only between plants and herbivores but also between ants and herbivores.
Regional differences in the morphology of a shrub Damnacanthus indicus: An induced resistance to deer herbivory?
Authors: Takada Mayura , Asada Masahiko , Miyashita Tadashi
Published: March 2003

We report here the possibility of an induced resistance of a spiny shrub Damnacanthus indicus against deer herbivory. Six characters of D. indicus were compared between regions with and without deer herbivory on the Boso Peninsula. We found that D. indicus in browsed areas produced smaller leaves, thicker spines, and shorter internode distances between spines than those in unbrowsed areas whereas the length of spines and the angle of a pair of spines did not differ significantly. It is likely that D. indicus shows an induced resistance by producing smaller leaves, and by increasing stoutness of spines and spine density.
Characteristics of insect populations on habitat fragments: A mini review
Authors: Tscharntke Teja , Steffan‐Dewenter Ingolf , Kruess Andreas , Thies Carsten
Published: March 2003

Modern human‐dominated landscapes are typically characterized by intensive land‐use and high levels of habitat destruction, often resulting in sharply contrasted habitat mosaics. Fragmentation of remaining habitat is a major threat to biodiversity. In the present paper, we focus on the different features of habitat fragmentation. First we discuss the importance of pure habitat loss, fragment size, fragment isolation and quality, edge effects, and the importance of landscape structure. Second, we characterize life‐history features of fragmentation‐sensitive species, showing that rare, specialized, little dispersing species are most affected, as well as species characterized by high population variability and a high trophic position, while the effect of body size is unclear. Third, we discuss the conservation value of habitat fragments. The question arises how to relate studies on population survival to those of community structure and studies on biodiversity to those on ecologicalal functions. Despite the general superiority of large to small reserves, only small or medium‐sized reserves are available in many human‐dominated landscapes. A great number of small habitats covering a wide range of geographic area should maximize beta diversity and spreading of risk and may be very important for the regional conservation of biodiversity, in contrast to the prevailing arguments in favor of large habitats. Finally, landscape context influences community structure of fragments, and communities are composed of species that experience the landscape on a broad range of spatial scales. Spatial arrangement of habitat fragments in a landscape appears to be important only in simple, not complex landscapes.
Photosynthesis–nitrogen relationships in species at different altitudes on Mount Kinabalu, Malaysia
Authors: Hikosaka Kouki , Nagamatsu Dai , Ishii Hiroshi S. , Hirose Tadaki
Published: March 2003

In situ photosynthetic nitrogen‐use efficiency (PNUE, photosynthetic capacity per unit leaf nitrogen) was investigated in species that commonly distributed at different altitudes (600–3700 m above sea level) on Mount Kinabalu. Photosynthetic nitrogen‐use efficiency was lower in species at higher altitudes, with a mean PNUE at 3700 m being one‐third as large as that at 600 m. This difference in PNUE was larger than that explained by the biochemical response to lower air pressures only. Across altitudes a negative correlation between 13C abundance (δ13C) and PNUE was found. Species at higher altitudes tended to have higher δ13C, suggesting that they had a lower conductance for CO2 diffusion from the air to chloroplasts. The lower conductance might be responsible for the lower PNUE in species at higher altitudes. Although leaf nitrogen content per unit area tended to be higher at higher altitudes, it did not seem to contribute to increasing photosynthetic rates. Thus, the idea that a higher nitrogen content at higher altitudes is a compensation for a lower PNUE was not supported. In contrast to the large difference in PNUE among altitudes, PNUE tended to converge within a narrow range among species growing at the same altitude.
Splash seed dispersal by raindrops
Authors: Nakanishi Hiroki
Published: March 2003

Splash seed dispersal by raindrops was investigated for plants in southern Japan. Nine families, 10 genera and 19 species were confirmed as raindrop‐dispersed plants. The 10 genera were Gentiana, Gratiola, Chrysosplenium, Mazus, Mitella, Ophiorrhiza, Sagina, Sedum, Trigonotis and Veronica. The method of splash rain dispersal in these species was clarified. Raindrop‐dispersed species were all small herbaceous plants with a vertical pedicel and an apically opening fresh capsule when the seeds mature. Open capsules were cup‐shaped or boat‐shaped and can accommodate raindrops easily. The raindrops splashed the seeds from the capsule. In general, the seeds weighed very little, but they were heavier than powder or dust seeds dispersed by wind. A strong negative correlation was found between seed weight and the number of seeds per capsule. In the case of Trigonotis brevipes (Maxim.) Maxim., raindrops were received into the cup‐shaped calyx‐tube and dispersed the fruitlets. Some species, such as Gentiana thunbergii (G. Don) Griseb., Gentiana zollingeri Fawcett and Ophiorrhiza japonica Blume, had hydroscopic movement capsules that opened widely only when wet. Raindrop‐dispersed plants were found in various habitats. For example, some plants grew together on rocks along the mountain torrents where splash water could easily be caught. The results of the laboratory and field experiments indicated that the dispersal distance of seeds by raindrops was 1 m or less. For small herbaceous plants, splash dispersal by rain might be an effective and advantageous method of seed dispersal because dispersal is not affected by plant height.
Prehibernal insemination and short dispersal of Ceratina flavipes (Hymenoptera: Anthophidae) in northernmost Japan
Authors: KIDOKORO MIDORI , KIKUCHI TOMONORI , HIRATA MASANORI
Published: March 2003

Although females of Ceratina flavipes are believed to be inseminated in spring on Honshu Island, Japan, 100% of the females were inseminated before hibernation on Ishikari Coast, northernmost Japan. Because most, if not all, of the males also overwintered with the females, this prehibernal insemination may be a local event. In the hibernal season, females were more frequently alone in nests than males, whereas the sex ratio in their main habitat was almost 1:1, suggesting that prehibernal dispersal is more frequent in females, but that the dispersal distance is shorter than previously reported.
Of mites and bees: A review of mite–bee associations in Australia and a revision of Raymentia Womersley (Acari: Mesostigmata: Laelapidae), with the description of two new species of mites from Lasioglossum (Parasphecodes) spp. (Hymenoptera: Halictidae)
Authors: Walter David Evans , Beard Jennifer J , Walker Ken L , Sparks Kathryn
Published: March 2003

Social bees have a diverse fauna of symbiotic mesostigmatic mites, including highly pathogenic parasites of the honeybee, but there are few reports of Mesostigmata phoretic on or inhabiting the nests of solitary or communal, ground‐nesting bees. In south‐eastern Australia, however, native bees in the family Halictidae carry what appears to be a substantial radiation of host‐specific mesostigmatans in the family Laelapidae. Herein, we redescribe the obscure genus Raymentia, associated with Lasioglossum
(Parasphecodes) spp. bees (Halictidae) and describe two new species, R.
eickwortiana from L. lacthium (Smith) and R. walkeriana from L.
atronitens (Cockerell). The type species, R. anomala Womersley, is associated
with L. altichum (Smith). In addition, we review the mites known to be associated
with Australian bees, provide a key to differentiate them, and describe and illustrate
acarinaria of the Halictinae. We also report on the first occurrences in Australia
of the genera Trochometridium Cross (Heterostigmata: Trochometridiidae), from
L. eremaean Walker (Halictidae), and Cheletophyes Oudemans (Prostigmata:
Cheyletidae) from Xylocopa Latreille (Xylocopinae), and on the previously
unknown association between a Neocypholaelaps Vitzthum (Mesostigmata: Ameroseiidae)
and Lipotriches tomentifera (Friese) (Halictidae).
The toxicity of antidepressant poisoning: Is it changing? A comparative study of cyclic and newer serotonin‐specific antidepressants
Authors: Graudins Andis , Dowsett Robert P , Liddle Christopher
Published: March 2003

Aim: To compare the clinical features of cyclic antidepressant and newer, non‐cyclic, serotonin‐specific antidepressant poisoning.

Methods: Comparitive, descriptive study of all antidepressant overdose patients admitted to a hospital toxicology service from February 1997 to April 2001. Patient data were entered prospectively into a dedicated toxicology database for subsequent analysis.

Results: There were 256 admissions for antidepressant poisoning (17.5% of all poisoning admissions). Cyclic antidepressant poisoning comprised 43% of antidepressant admissions. Statistically significant differences between the two groups included: cyclic antidepressant group had longer median length of stay (23.1 vs 15.9 h, P = 0.0008), greater need for endotracheal intubation (31%vs 4%, OR = 11.5, P < 0.0001) and higher incidence of seizures (7.2%vs 0.7%, OR = 10.4, P = 0.01), faster median pulse rate, longer QRS‐interval on admission, and longer intensive care unit stays. However, non‐cyclic, serotonin‐specific antidepressant poisonings involved larger doses of antidepressants and were more likely to ingest other medications along with these. Serotonin syndrome was only seen in non‐cyclic, serotonin‐specific poisoning (10.3%, OR = 26.6, P = 0.0002). Patients with serotonin syndrome had a longer median hospital stay (46 vs 16 h, P < 0.0002) compared to other non‐cyclic, serotonin‐specific patients. There were no deaths during the study period.

Conclusions: Cyclic antidepressants still comprise a significant proportion of antidepressant poisoning and result in more significant morbidity than non‐cyclic, serotonin‐specific poisoning. Clinicians should also be aware that non‐cyclic, serotonin‐specific poisoning may result in the development of serotonin syndrome. This was the most significant toxic effect noted following non‐cyclic, serotonin‐specific poisoning in this study.
Buffering the pain of local anaesthetics: A systematic review
Authors: Davies Robert John
Published: March 2003

Objective: To review the evidence that buffering of local anaesthetics with sodium bicarbonate reduces the pain of injection whilst not affecting efficacy.

Methods: Medline search from 1966 to December 2001. Articles in all languages were included. Bibliographies were examined for papers.

Results: The search identified 63 publications. All were retrieved. Of these, 22 were human prospective randomized controlled trials directly assessing the pain of infiltration. Three papers were based on observations. No case series, case reports, or retrospective studies were identified. One animal study was found.

Conclusion: The evidence is that buffering with sodium bicarbonate significantly reduces the pain of local anaesthetic injection. The buffered solutions retain the efficacy of local anaesthetics and are stable in the mixtures used in the trials. Adrenaline‐containing buffered solutions need refrigeration in closed containers for storage. Buffering will be particularly useful where pain of local anaesthetic injection may not be well tolerated such as in large areas of infiltration, sensitive areas such as the face and in children. It is recommended that sodium bicarbonate and tables of stable dilutions are readily available in the emergency department to facilitate this.
Comparative seed ecology of the endangered shrub,Pimelea spicataand a threatening weed, Bridal Creeper: Smoke, heat and other fire‐related germination cues
Authors: Willis Anthony J. , McKay Rachel , Vranjic John A. , Kilby Marion J. , Groves Richard H.
Published: March 2003

SummaryPimelea spicataR. Br. is a nationally listed endangered Australian shrub threatened with extinction by habitat fragmentation and environmental weed invasion. Bridal Creeper (Asparagus asparagoidesL. W. Wight) is the primary weed threat to the largest remaining populations ofP. spicatain the Cumberland Plain. Fire, as part of an integrated pest management program, offers the potential to stimulateP. spicatapopulations while controlling Bridal Creeper. It is important, therefore, to understand how the components of fire affect the germination and growth of both species. Using laboratory experiments we investigated the effects of smoke, heat, ash and/or light on the germination ofP. spicataand Bridal Creeper. We found a significant promotive effect of smoke and indication of an inhibitory heat shock (90°C for 10 min) effect on the germination ofP. spicataseeds. The response of Bridal Creeper seeds to the same factors was complex; while the results of one experiment suggested an inhibitory effect of smoke and a promotive effect of heat, subsequent trials were contradictory, implying that Bridal Creeper, like many weeds, is able to germinate under a wide range of environmental conditions. Other experiments investigated the optimal germination temperature and innate dormancy ofP. spicatain the absence of fire‐related germination cues. Of the incubation temperatures investigated, the optimal diurnally fluctuating regime forP. spicatagerminations was 10°C and 20°C in the night and day, respectively. The innate dormancy of freshly produced seeds disappeared after 3 months. In contrast to Bridal Creeper, we found a persistent germinable seed bank of about 97P. spicataseeds/m2located in the top 5 cm of the soil profile. While fire alone is unlikely to kill Bridal Creeper plants, fire may help to manage local infestations of the weed by limiting germination and providing opportunity for herbicide treatment of regrowth.
Pro‐inflammatory cytokine/chemokine gene expression in human corneal epithelial cells colonized by Pseudomonas aeruginosa
Authors: Xue Ml , Thakur A , Lutze‐Mann L , Willcox Mdp
Published: March 2003

Pro‐inflammatory cytokines interleukin‐6 (IL‐6), interleukin‐1β (IL‐1β), tumour necrosis factor‐α (TNF‐α) and chemokine interleukin‐8 (IL‐8) may play a significant role in the regulation of bacterial corneal infection. The aim of this study was to investigate the gene expression of these four mediators in a human corneal epithelial cell line challenged with Pseudomonas aeruginosa within 12 h. Human corneal epithelial monolayers were colonized with P. aeruginosa strains Paer1, 6206 and 6294. Expression of IL‐6, IL‐8, IL‐1β and TNF‐α was analysed using semi‐quantitative reverse transcription–polymerase chain reaction. Results showed that both IL‐6 and IL‐8 mRNA were expressed very early (4 h) during bacterial colonization and remained at high levels until the end of the experiment. Expression of IL‐1β and TNF‐α mRNA appeared at 8 h after bacterial stimulation. No expression of IL‐8, IL‐1β and TNF‐α mRNA was observed in unstimulated cells. Interleukin‐6 mRNA was expressed at low levels in unstimulated cells. In conclusion, bacterial colonization of human corneal epithelial cells induced expression of IL‐6 and IL‐8 mRNA earlier and at higher levels than IL‐1β and TNF‐α mRNA.
Changes in attitudes and practices of optometrists in their management of diabetic retinopathy after the release of NHMRC guidelines
Authors: Wright Suzie E , McKay Rob , Taylor Kathryn I , Keeffe Jill E , McCarty Catherine A ,   Working Group for the Evaluation of Nhmrc Retinopathy Guideline Distribution
Published: March 2003

The purpose of this study was to document attitudes and practices of Australian optometrists in their management of diabetic retinopathy prior to the release of the National Health and Medical Research Council (NHMRC) Clinical Practice Guidelines for the Management of Diabetic Retinopathy and at two time points following their release. A self‐ administered questionnaire was mailed to a stratified random sample of 500 Australian optometrists at the three time points. The same sample was used for the first two surveys and a new random sample was drawn for the second follow‐up survey. The response to the three questionnaires was 86%, 80% and 84%, respectively. More than 90% of optometrists reported receiving a copy of the guidelines and 82% reported receiving the supplementary Retinopathy Chart. Fifty‐seven per cent reported having read the guidelines at least once in entirety and 65% reported that they refer to the Retinopathy Chart at least monthly in their clinical practice. There was a significant decrease in the number of optometrists who reported that patient unwillingness to be dilated and their fear of precipitating angle closure glaucoma were moderate or major barriers to performing dilated ophthalmoscopy. Concomitantly, the percentage of optometrists who reported that they often or always perform dilated ophthalmoscopy on new patients with diabetes increased significantly from 74.5% (95% confidence limit = 70.2, 78.8) to 81.5% (95% confidence limit = 77.5, 85.5). There have been some significant changes in the self‐reported management practices of optometrists in relation to diabetic retinopathy since the release of the NHMRC guidelines and Retinopathy Chart.
Acquired hyperopia with choroidal folds
Authors: Murdoch David , Merriman Michael
Published: March 2003

Acquired hyperopia with choroidal folds is an uncommon but well recognized condition that is often benign and classically shows flattening of the posterior pole of the affected eye, variable enlargement of the optic nerve complex, and a space between the optic nerve and its sheath. A case is presented that shows the perineural space is best seen on magnetic resonance imaging. Lumbar puncture to exclude increased intracranial pressure should be performed even in the absence of papilloedema.
Serpiginous choroidopathy: an unusual association with Crohn's disease
Authors: Ugarte Marta , Wearne I Michael J
Published: March 2003

Serpiginous choroidopathy, an inflammatory chorioretino­pathy characterized by areas of choroidal atrophy and scarring, has previously been described in association with various systemic granulomatous disorders, but has not been linked to Crohn's disease. There are reports of ocular posterior segment abnormalities in patients with this chronic, granulomatous, inflammatory bowel disease, but these have not included serpiginous choroidopathy. This is the first report suggesting a link between serpiginous choroidopathy and Crohn's disease. A 22‐year‐old woman presented with serpiginous choroidopathy in whom Crohn's disease was diagnosed soon after. After starting treatment with oral prednisolone, no further visual loss or progression of the chorioretinal lesions occurred. The T‐cell mediated nature of both inflammatory disorders and the temporal association in their onset suggests a possible link between serpiginous choroidopathy and Crohn's disease.
Three‐Dimensional Reconstruction of the Mucosa from Sequential Sections of Biopsy Specimens for Understanding Disease Progress in Ulcerative Colitis
Authors: Furukawa Hiroo , Asai Satoshi , Moriyasu Takayuki , Ono Hisako , Saiga Tatsuyoshi
Published: March 2003

Background: This paper describes the creation of 3‐D computer graphic images of the mucosal crypt of ulcerative colitis (UC) and the resulting observations, which may have great significance to our understanding of the mechanisms involved in the progress of this disease.

Methods: Endoscopic biopsy specimens of normal, diseased and transitional (the border area between normal and diseased) zones of the mucosa were taken from five different patients of various ages and at various periods in the progress of their diseases. Three‐dimensional reconstruction of these specimens was perfomed using TRI for Windows (RATOC System Tokyo, Japan) as software.

Results: Clear stereographic images exhibiting the structures of crypts, the effects and the progress of UC were obtained. It was seen that, (i) moving from normal to transitional and to diseased zones, the value for crypt volume and crypt surface area increased, but at a far lower rate than those representing the lumen volume and surface area, (ii) the numbers of crypts and crypt lumina decreased as inflammation became more severe and (iii) it is likely that there is a specific point (the intermediate portion of the crypt) which is attacked by inflammation in ulcerative colitis.

Conclusion: This method, of stereographic analysis by computer, has opened a new door to the study of a whole range of inflammatory bowel diseases.
Clinical evaluation of double stenting for duodenal and biliary obstructions caused by pancreatic head carcinoma using covered self‐expandable metallic stents
Authors: Hayashi Kazuki , Okayama Yasutaka , Hirai Masaaki , Kitajima Yasuhiro , Imai Hideto , Okamoto Tetsu , Akita Shinji , Gotoh Kazuo , Sano Hitoshi , Ohara Hirotaka , Nomura Tomoyuki , Joh Takashi , Yokoyama Yoshifumi , Itoh Makoto
Published: March 2003

Five patients with non‐resectable pancreatic head carcinoma complicated by duodenal and biliary obstructions were successfully treated by double stenting with covered self‐expandable metallic stents (EMS). Diamond (Boston Scientific, Natick City, MA, USA) stents covered with a polyurethane membrane were used to treat biliary obstructions, whereas covered Ultraflex (Boston Scientific) stents for esophageal stenting were used to treat duodenal obstructions. That is, Diamond stents were initially placed in the biliary tract percutaneously in one patient and endoscopically in the remaining four patients. Subsequently, covered Ultraflex stents were placed in the duodenum. Double stenting with EMS was successfully performed in all five patients without inducing early technical complications. All patients were able to take a liquid diet orally at a mean 1.6 days after the double stenting procedure and were able to eat solid foods thereafter. Sludge‐induced biliary obstructions were detected in two patients 3 and 6 months after the placement of EMS. However, recurrent biliary obstruction was not noted in the remaining three patients. The EMS left in the duodenum were not obstructed during the observation period. The survival period of the patients ranged from 86 to 363 days (mean 172 days). There have not been any reports evaluating the usefulness of double stenting using covered EMS for duodenal and biliary obstructions. Because favorable results were obtained by double stenting in our patients, stenting for duodenal and biliary obstructions caused by non‐resectable pancreatic head carcinoma may become a useful treatment modality substituting for bypass surgery.