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Remnants
Kinds of Remnants Terms modified by Remnants Selected AbstractsA cranial base of Australopithecus robustus from the hanging remnant of Swartkrans, South AfricaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2006Darryl J. de Ruiter Abstract SKW 18, a partial hominin cranium recovered from the site of Swartkrans, South Africa, in 1968 is described. It is derived from ex situ breccia of the Hanging Remnant of Member 1, dated to approximately 1.5,1.8 Mya. Although partially encased in breccia, it was refit to the facial fragment SK 52 (Clarke 1977 The Cranium of the Swartkrans Hominid SK 847 and Its Relevance to Human Origins, Ph.D. dissertation, University of the Witwatersrand, Johannesburg), producing the composite cranium SKW 18/SK 52. Subsequent preparation revealed the most complete cranial base attributable to the species Australopithecus robustus. SKW 18 suffered weathering and slight postdepositional distortion, but retains considerable anatomical detail. The composite cranium most likely represents a large, subadult male, based on the incomplete fusion of the spheno-occipital synchondrosis; unerupted third molar; pronounced development of muscular insertions; and large teeth. Cranial base measures of SKW 18 expand the range of values previously recorded for A. robustus. SKW 18 provides information on anatomical features not previously visible in this taxon, and expands our knowledge of morphological variability recognizable in the cranial base. Morphological heterogeneity in the development of the prevertebral and nuchal muscular insertions is likely the result of sexual dimorphism in A. robustus, while differences in cranial base angles and the development of the occipital/marginal sinus drainage system cannot be attributed to size dimorphism. Am J Phys Anthropol, 2006. © 2006 Wiley-Liss, Inc. [source] Alternatives for Reintroducing a Rare Ecotone Species: Manually Thinned Forest Edge versus Restored Habitat RemnantRESTORATION ECOLOGY, Issue 5 2009Jennifer Possley Abstract Species native to ecotones are often overlooked in restoration efforts despite the increasing rarity of ecotone habitat. In fragmented, fire-suppressed landscapes, true ecotone may no longer exist. Restoration biologists interested in reintroducing ecotone species must decide whether to plant them in historic ecotones maintained by manual thinning or whether to opt for discrete restoration areas that are easier to maintain. We investigated these two alternatives with Lantana canescens, a rare tropical shrub native to the ecotone between pine and hardwood forests of Miami-Dade County, Florida, U.S.A. Our short-term findings show that after 15 and 18 months, survival of transplants was 69% in a restored site and 65% and 84% in two historic ecotone sites. The restored site had significantly higher photosynthetically active radiation (PAR) (75%) than the historic ecotones (25,39%). Correspondingly, 267 seedlings have recruited at the restored site, whereas only 8 have emerged at both historic ecotone sites. Seedling establishment was associated with higher PAR at the restored site. We found that overall population sustainability was higher at the restored site where there is the additional benefit of less maintenance. Our work suggests that, by reducing succession, a discrete restoration area can approach the historic conditions of hardwood/pine forest ecotone more closely than degraded historic ecotones themselves. We present a viable solution for conserving rare ecotone species when their natural habitat and the processes that maintained it no longer exist. [source] Remnants of the Waikato: Native forest survival in a production landscapeNEW ZEALAND GEOGRAPHER, Issue 1 2005Mairi Jay Abstract:, This paper addresses the issue of conservation of native biodiversity on privately owned farmland in New Zealand. Based on surveys of Waikato dairy farmers as exemplars of intensive agricultural practice, it examines factors that influence the survival of native forest on land with potential for commercial production. Results suggest that a significant proportion of Waikato dairy farmers regard native forest favourably, although the proportion of farmers who actively conserve their forest is small. Factors that assist the persistence of native forest on dairy farms include personal characteristics of the farmer, past accidents of history which have left forest remnants in place, and physical characteristics of the farm such as topography. While the conservation of native biodiversity within this intensively farmed landscape is strongly influenced by political economy pressures that encourage production, non-utilitarian motives such as aesthetic enjoyment and family heritage can serve to counter the production ethic. [source] Remnants of secondarily necrotic cells fuel inflammation in systemic lupus erythematosusARTHRITIS & RHEUMATISM, Issue 6 2009Luis E. Muñoz Objective Patients with systemic lupus erythematosus (SLE) are often characterized by cellular as well as humoral deficiencies in the recognition and phagocytosis of dead and dying cells. The aim of this study was to investigate whether the remnants of apoptotic cells are involved in the induction of inflammatory cytokines in blood-borne phagocytes. Methods We used ex vivo phagocytosis assays comprising cellular and humoral components and phagocytosis assays with isolated granulocytes and monocytes to study the phagocytosis of secondarily necrotic cell,derived material (SNEC). Cytokines were measured by multiplex bead array technology. Results We confirmed the impaired uptake of various particulate targets, including immunoglobulin-opsonized beads, by granulocytes and monocytes from patients with SLE compared with healthy control subjects. Surprisingly, blood-borne phagocytes from two-thirds of the patients with SLE took up SNEC, which was rarely phagocytosed by phagocytes from healthy control subjects or patients with rheumatoid arthritis. Supplementation of healthy donor blood with IgG fractions derived from patients with SLE transferred the capability to take up SNEC to the phagocytes of healthy donors. Phagocytosis-promoting immune globulins also induced secretion of huge amounts of cytokines by blood-borne phagocytes following uptake of SNEC. Conclusion Opsonization of SNEC by autoantibodies from patients with SLE fosters its uptake by blood-borne monocytes and granulocytes. Autoantibody-mediated phagocytosis of SNEC is accompanied by secretion of inflammatory cytokines, fueling the inflammation that contributes to the perpetuation of autoimmunity in SLE. [source] Culture and Characterization of Human Hepatocytes Obtained after Graft Reduction for Liver Transplantation: A Reliable Source of Cells for a Bioartificial LiverARTIFICIAL ORGANS, Issue 7 2004Mariana Barbich Abstract:, This article describes results obtained when human liver cells obtained from reduced grafts are cultured in a chemically defined medium. Remnants of livers after reduction for pediatric transplantation were processed by a multiple cannulation system through the existing vasculature, which allowed the homogeneous perfusion of collagenase. The graft weight ranged between 55 and 1000 g (median value: 145.6 g). The yield ranged between 0.13 × 106 and 38 × 106 cells/g of tissue (median value 14.73 × 106 cells/g), and the viability was 61.17 ± 27.43%. The total number of cells ranged between 57.6 × 106 and 12 150 × 106 cells (median value: 740 × 106 cells). Cells were cultured for 30 days. Albumin synthesis was observed during the first 2 weeks, with a peak value at day 6 (27.85 ± 1.77 µg/mL). Urea production was detected during the first week (peak value at day 6: 17.12 ± 2.11 mg/dL). Light microscopy showed the presence of cells in a monolayer. Biliary pigments were observed at day 20. By immunohistochemistry, positive cells for albumin, for hepatocyte marker, cytokeratin 19, CD 34, CD 68, and for alpha actin for smooth muscle, were observed. Our results showed that hepatocytes obtained from reduced liver grafts are easily cultured and are able to maintain viability and functionality in vitro. This alternative source of human cells maintained under controlled culture conditions may play an important role in the development of a bioartificial liver. [source] Predicting potential impacts of environmental flows on weedy riparian vegetation of the Hawkesbury,Nepean River, south-eastern AustraliaAUSTRAL ECOLOGY, Issue 5 2000Jocelyn Howell Abstract Remnants of native riparian vegetation on the floodplain of the Hawkesbury,Nepean River near Sydney, have significant conservation value, but contain a large component of weeds (i.e. exotic species that have become naturalized). A proposal for the introduction of environmental flows required an assessment of potential impacts on 242 native and 128 exotic species recorded along 215 km of the river. The likely effects of frequency, season, depth and duration of inundation were considered in relation to habitat, dispersal season and tolerance to waterlogging. Overseas studies provided only limited information applicable to the study area; however, comparisons with similarly highly modified riparian habitats in New Zealand were instructive. Depth and season of inundation appear to be the variables with the greatest potential for differential effects on weeds and native plants. Because of likely spread of propagules and enhancement of growth under the present nutrient-enriched conditions, environmental flows that would cause more frequent flooding to higher levels of the riparian zone were judged to be of more benefit to weed species than native species, unless supported by bushland management including weeding. Predictions were limited by incomplete data on Hawkesbury,Nepean species, but two types of environmental flow were judged to be potentially beneficial for native water-edge plants, and worth testing and monitoring: first, flows that maintain continuous low-level flow in the river, and second, higher level environmental flows restricted to the river-edge habitat in autumn (the season in which a greater proportion of native species than weed species are known to disperse propagules). In summary, the presence of environmental weeds in riparian vegetation constrain the potential for environmental flows to improve river health. However, with ongoing monitoring, careful choice of water level and season of flow may lead to environmental flows that add to our knowledge, and benefit riparian vegetation along with other river system components. [source] Middle Weichselian glacial event in the central part of the Scandinavian Ice Sheet recorded in the Hitura pit, Ostrobothnia, FinlandBOREAS, Issue 1 2008VELI-PEKKA SALONEN The Hitura open pit exposes a sedimentary sequence up to 50 m thick representing Late Saalian to Holocene glacial and non-glacial sediments. The sequence was investigated using sedimentological methods, OSL-dating and pollen and diatom analyses to reconstruct the Middle Weichselian (MWG) glacial event in the central part of the Scandinavian Ice Sheet (SIS). The results indicate that the sediment succession represents two entire glacial advance and retreat cycles. The lowermost deposits are Late Saalian esker and delta sediments overlain by sediments that correlate with the early Eemian lacustrine phase. Remnants of the Eemian soil post-dating the lacustrine phase were also observed. The area was ice-free during the entire Early Weichselian (EWG). The first glacial advance recorded in the sediments is related to the MWG. It started 79 kyr ago, deformed underlying sediments and deposited an immature till, including large detached sediment pods containing remains of organic material, soils and fluvial sediments representing allochthonous material from EWG ice-free stadials and interstadials. The glacial deposits are conformably overlain by glaciolacustrine and littoral accumulations, indicating MWG deglaciation between 62 and 55 kyr ago. Based on the fabric measurements from the till unit overlying the MWG sediments, ice advance during the Late Weichselian (LWG) was initially from the west and later from a north-northwesterly direction. The Hitura strata provide the first dating of the MWG deglaciation (55 to 62 kyr ago) from central parts of the SIS. It can be considered as a key site for studying the growth and decay of SIS during the poorly known early parts of the glaciation. [source] Microtubule sliding movement in tilapia sperm flagella axoneme is regulated by Ca2+/calmodulin-dependent protein phosphorylationCYTOSKELETON, Issue 8 2006Masaya Morita Abstract Demembranated euryhaline tilapia Oreochromis mossambicus sperm were reactivated in the presence of concentrations in excess of 10,6 M Ca2+. Motility features changed when Ca2+ concentrations were increased from 10,6 to 10,5 M. Although the beat frequency did not increase, the shear angle and wave amplitude of flagellar beating increased, suggesting that the sliding velocity of microtubules in the axoneme, which represents dynein activity, rises with an increase in Ca2+. Thus, it is possible that Ca2+ binds to flagellar proteins to activate flagellar motility as a result of the enhanced dynein activity. One Ca2+ -binding protein (18 kDa, pI 4.0), calmodulin (CaM), was detected by 45Ca overlay assay and immunologically. A CaM antagonist, W-7, suppressed the reactivation ratio and swimming speed, suggesting that the 18 kDa Ca2+ -binding protein is CaM and that CaM regulates flagellar motility. CaMKIV was detected immunologically as a single 48 kDa band in both the fraction of low ion extract of the axoneme and the remnant of the axoneme, suggesting that CaMKIV binds to distinct positions in the axoneme. It is possible that CaMKIV phosphorylates the axonemal proteins in a Ca2+/CaM-dependent manner for regulating the dynein activity. A 32P-uptake in the axoneme showed that 48, 75, 120, 200, 250, 380, and 400 kDa proteins were phosphorylated in a Ca2+/CaM kinase-dependent manner. Proteins (380 kDa) were phosphorylated in the presence of 10,5 M Ca2+. It is possible that an increase in Ca2+ induces Ca2+/CaM kinase-dependent regulation, including protein phosphorylation for activation/regulation of dynein activity in flagellar axoneme. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Evaluation of tooth-fragment reattachment: a clinical and laboratory studyDENTAL TRAUMATOLOGY, Issue 4 2010Yucel Yilmaz Materials and Methods:, The clinical study was conducted on 43 fractured incisors: 22 uncomplicated crown fractures (Group A) and 21 complicated crown fractures (Group B). The 43 incisal fragments: 23 were kept dry for 47 h and 20 were kept wet for 24 h by the patients before they were reattached. The fragments were kept in 0.9% saline solution for 30 min before reattachment. The fragments in Group A were reattached using a dentin bonding agent, a flowable and a hybrid resin composite, whereas the fragments in Group B were reattached to the tooth remnant after a pulpotomy was performed. The laboratory study was conducted on 56 extracted incisors. Teeth were divided equally into four groups: Group I , Uncomplicated crown fracture + wet medium; Group II , Uncomplicated crown fracture + dry medium; Group III , Complicated crown fracture + wet medium, and Group IV , Complicated crown fracture + dry medium. The fragments were then reattached in a manner that was similar to that used in the clinical study. The restored teeth were then re-fractured. All data were analyzed statistically. Results: In the clinical study, the restored teeth were followed up for 2 years. Neither the type of trauma nor the storage medium had any significant effect on the survival, color, and bond strength of the restored teeth when assessed in the clinical and laboratory study. The color disharmony that was encountered initially in restored teeth resolved significantly on its own accord within 12 months after reattachment of the fragment. Conclusion: Fragment reattachment can be used to treat fractured teeth successfully in children and adolescents. [source] Developmental changes in the modulation of respiratory rhythm generation by extracellular K+ in the isolated bullfrog brainstemDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2003Rachel E. Winmill Abstract This study tested the hypothesis that voltage-dependent, respiratory-related activity in vitro, inferred from changes in [K+]o, changes during development in the amphibian brainstem. Respiratory-related neural activity was recorded from cranial nerve roots in isolated brainstem,spinal cord preparations from 7 premetamorphic tadpoles and 10 adults. Changes in fictive gill/lung activity in tadpoles and buccal/lung activity in adults were examined during superfusion with artificial CSF (aCSF) with [K+]o ranging from 1 to 12 mM (4 mM control). In tadpoles, both fictive gill burst frequency (fgill) and lung burst frequency (flung) were significantly dependent upon [K+]o (r2 > 0.75; p < 0.001) from 1 to 10 mM K+, and there was a strong correlation between fgill and flung (r2 = 0.65; p < 0.001). When [K+]o was raised to 12 mM, there was a reversible abolition of fictive breathing. In adults, fictive buccal frequency (fbuccal), was significantly dependent on [K+]o (r2 = 0.47; p < 0.001), but [K+]o had no effect on flung (p > 0.2), and there was no significant correlation between fbuccal and flung. These data suggest that the neural networks driving gill and lung burst activity in tadpoles may be strongly voltage modulated. In adults, buccal activity, the proposed remnant of gill ventilation in adults, also appears to be voltage dependent, but is not correlated with lung burst activity. These results suggest that lung burst activity in amphibians may shift from a "voltage-dependent" state to a "voltage-independent" state during development. This is consistent with the hypothesis that the fundamental mechanisms generating respiratory rhythm in the amphibian brainstem change during development. We hypothesize that lung respiratory rhythm generation in amphibians undergoes a developmental change from a pacemaker to network-driven process. © 2003 Wiley Periodicals, Inc. J Neurobiol 55: 278,287, 2003 [source] ENDOSCOPIC OCCLUSION OF CYSTIC DUCT USING N -BUTYL CYANOACRYLATE FOR POSTOPERATIVE BILE LEAKAGEDIGESTIVE ENDOSCOPY, Issue 4 2010Eric K. Ganguly Bile leak after cholecystectomy is well described, with the cystic duct remnant the site of the leak in the majority of cases. Endoscopic retrograde cholangiopancreatography (ERCP) with biliary stent placement has a high success rate in such cases. When ERCP fails, options include surgery, and percutaneous and endoscopic transcatheter occlusion of the site of bile leak. Here, we describe a case of endoscopic transcatheter occlusion of a persistent cystic duct bile leak after cholecystectomy using N -butyl cyanoacrylate glue. A 51-year-old man had persistent pain and bilious drainage following a laparoscopic cholecystectomy. The bile leak persisted after endoscopic placement of a biliary stent for a confirmed cystic duct leak. A repeat ERCP was carried out and the cystic duct was occluded with a combination of angiographic coils and N -butyl cyanoacrylate glue. The patient's pain and bilious drainage resolved. A follow-up cholangiogram confirmed complete resolution of the cystic duct leak and a patent common bile duct. [source] Successful Endoscopic Band Ligation for Treatment of Postpolypectomy HemorrhageDIGESTIVE ENDOSCOPY, Issue 4 2000Yohei Mizuta We describe a case of large pedunculated tubulovillous adenoma of the stomach associated with postpolypectomy hemorrhage, which was successfully treated by endoscopic band ligation. The case study involved a 60-year-old Japanese woman with a pedunculated polyp with a slightly lobular surface, measuring 25 mm in diameter. It was detected on the posterior wall of the middle body of the gastric remnant. The lesion was diagnosed as a tubulovillous adenoma by a biopsy specimen and treated by endoscopic polypectomy using the detachable snare to prevent postpolypectomy hemorrhage. There was no episode of immediate postpolypectomy hemorrhage, but hematemesis occured 18 h after the excision. Endoscopic examination of the stomach showed the mark left by bleeding on the cutting surface and the absence of the detachable snare. Endoscopic intervention by rubber band ligation was performed to prevent the recurrent bleeding. Complete hemostasis was obtained and no serious complications occured. [source] Competitive relationships of Andropogon gerardii (Big Bluestem) from remnant and restored native populations and select cultivated varietiesFUNCTIONAL ECOLOGY, Issue 3 2004D. J. GUSTAFSON Summary 1Although genetic differentiation among plant populations is well known, its relevance for preserving the integrity of native ecosystems has received little attention. In a series of competition experiments with Andropogon gerardii Vitman, a dominant species of the North American Tallgrass Prairie, plant performance was related to seed provenance and restoration activities. 2Glasshouse experiments showed plant performance to be a function of seed source. Differential target plant performance relative to competitor identity was observed when plant performance was assessed across a range of competitor densities. Local and non-local plants were larger when competing against non-local plants relative to the local and cultivar plants, while cultivar plants were consistently larger than local and non-local plants regardless of competitor identity or density. The consistency of cultivar performance could reflect directional selection during cultivar development for consistently high fecundity, vigorous vegetative growth and resistance to pathogens. 3In a field experiment, non-local plants were half the size of local and cultivar plants, supporting recognition of seed provenances of A. gerardii based on differences in plant performance among source populations observed in the glasshouse study, and previous genetic analyses of the same populations. 4This study establishes that seed provenance and restoration activities influence the competitive ability of a dominant species which, in turn, may affect plant community structure and potential ecosystem function. [source] Nectar ,theft' by hummingbird flower mites and its consequences for seed set in Moussonia deppeanaFUNCTIONAL ECOLOGY, Issue 1 2001Lara C. Summary 1,Mites (Acari: Mesostigmata: Ascidae) that live and feed in the flowers of about 100 plant species are transported in the nares of hummingbirds (Trochilidae). Mites may compete with hummingbirds for nectar secreted by the host plants, and this could affect the dynamics and reproductive outcomes of the mutualism between plants and their pollinating hummingbirds. 2,Here we combined field observations and experimental manipulations to assess the role of hummingbird flower mites (Tropicoseius sp. nov.) on nectar secretion and reproductive output of protandrous Moussonia deppeana (Schlecht. & Cham.) Hanst. (Gesneriaceae) during their flowering period in a cloud forest remnant. 3,During the 4 days that the flowers of M. deppeana last, flowers were visited exclusively by hummingbirds (Lampornis amethystinus). Bud production per inflorescence peaked in December. There were few open flowers per inflorescence in November, but numbers increased as the flowering season progressed (December and January). 4,The availability of each flower phase differed over the flowering season. Staminate-phase flowers were more abundant over the flowering season than pistillate-phase flowers. These differences were statistically significant over time. 5,Nectar availability was reduced by up to 50% in the presence of hummingbird flower mites. Over the 4 days of observation, significantly more nectar was secreted to flowers from which mites were excluded than to flowers with no mite exclusion. The same effect was observed during flowering, but mites consumed a greater percentage of the total nectar secreted in December. 6,Significantly more nectar was secreted during the staminate phase than in the pistillate phase, independent of time and treatment. 7,A manual pollination experiment suggested that mites act like secondary pollinators in this self-compatible, non-autogamous plant, at least in flowers that were not pollinated manually and had no access to pollinating hummingbirds. 8,Although seed production was not reduced significantly by flower mites, our results suggest that the presence of floral mites can affect pollen transmission, as the amount of nectar available to hummingbirds was reduced drastically. This can directly affect hummingbird foraging patterns and reduce the fitness of the host plants. [source] The bright spot in the West Carpathian upper mantle: a trace of the Tertiary plate collision,and a caveat for a seismologistGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2010Piotr SUMMARY The 2-D full waveform modelling of the mantle arrivals from the CELEBRATION 2000 profiles crossing the Carpathian orogen suggests two possible tectonic models for the collision of ALCAPA (Alpine-Carpathian-Pannonian) and the European Plate in the West Carpathians in southern Poland and Slovakia. Due to an oblique (NE-SW) convergence of plates, the character of the collision may change along the zone of contact of the plates: in the western part of the area an earlier collision might have caused substantial crustal shortening and formation of a crocodile-type structure, with the delaminated lower crust of ,100 km length acting as a north-dipping reflecting discontinuity in the uppermost mantle. In the eastern part, a less advanced collision only involved the verticalization of the subducted slab remnant after a slab break-off. The lower crustal remnant of ,10 km size in the uppermost mantle acts as a pseudo-diffractor generating observable mantle arrivals. Due to the similarity of synthetic data generated by both models, the question of the non-uniqueness of seismic data interpretation, that may lead to disparate tectonic inferences, is also discussed. [source] Comparison of structure and biodiversity in the Rajhenav virgin forest remnant and managed forest in the Dinaric region of SloveniaGLOBAL ECOLOGY, Issue 3 2000Andrej Boncina Abstract Comparisons are made between a virgin forest remnant (primeval forest) and a lightly managed (near-to-nature) forest with regard to horizontal forest structures, the structure of forest stands, and the diversity of plant and bird species. In the virgin forest remnant the proportion of canopy gaps is smaller, there are no stands in the developmental phase of a pole stand (10 < cm d.b.h. < 30 cm), and both the growing stock and the proportion of less vigorous trees are considerably greater. In addition, there is a higher percentage of dead trees, a smaller proportion of minor tree species and a considerably lower diversity of plants. The diversity of bird species is similar for each forest type, but rare bird species are confined to the virgin forest remnant. The biological differences between the two types of forest have led to changes in the physical site conditions. The results of the research are valuable in assessing the consequences of near-to-nature forest management. [source] Subsurface Transfer of Chloride After a Lake Retreat in the Central AndesGROUND WATER, Issue 5 2001Anne Coudrain The area under study covers 3500 km2 in the upstream part of the closed catchment basin of the salt crust of Uyuni. This crust is a remnant of the saline Lake Tauca, which covered the area about 15,000 years ago. In the downstream part of the aquifer, the Cl concentration of ground water and Cl content in the unsaturated zone exceed 20 meq/L and 18 kg/m2, respectively. With the present hydrological conditions under semiarid conditions, the ground water residence time in the study area exceeds 3000 years. Transient simulations over 11,000 years were made using initial conditions as the retreat of Lake Tauca and taking into account a low recharge during the arid mid-Holocene period. The modeling simulates ground water flow, Cl transport, and ground water residence time. It includes the evaporation from the aquifer that leads to the accumulation of chloride in the unsaturated zone. Results of the modeling are consistent with the observations if it is assumed that the Cl previously accumulated in the unsaturated zone was flushed back into the aquifer around 2000 years B.P., contemporaneously with the end of the arid period. [source] Current status of ectopic varices in Japan: Results of a survey by the Japan Society for Portal HypertensionHEPATOLOGY RESEARCH, Issue 8 2010Norihito Watanabe Aim:, The Clinical Research Committee of the Japan Society for Portal Hypertension has conducted a nationwide questionnaire survey to clarify the current status of ectopic varices in Japan. Methods:, A total of 173 cases of ectopic varices were collected. Results:, Duodenal varices were found in 57 cases, and most of them were located in the descending to transverse parts. There were 11 cases of small intestinal varices and 6 cases of colonic varices, whereas 77 patients had rectal varices, accounting for the greatest proportion (44.5%). Other sites of varices were the biliary tract, anastomotic sites, the stoma, and the diaphragm. Liver cirrhosis was the most frequent diseases (80.3%) underlying ectopic varices. It was noted that patients with rectal varices frequently had a history of esophageal varices (94.8%) and received endoscopic treatment (87.0%). The treatments for ectopic varices were as an emergency in 46.5%, elective in 35.4% and prophylactic in 18.2%. In emergency cases, endoscopic therapy was most frequent (67.4%), followed by interventional radiology (IVR; 15.2%), and endoscopy-IVR combination (6.5%). Elective treatment was performed by endoscopy in 34.3%, IVR in 28.6%, combined endoscopy-IVR in 5.7%, and surgical operation in 25.7%. The prophylactic treatment was endoscopic in 50.0%, IVR in 33.3%, combined treatments in 11.1%, and prophylactic surgery in none. The change of ectopic varices after treatment was disappearance in 54.9%, remnant in 35.4% and recurrence in 9.7%. The rate of disappearance was significantly lower in rectal varices (40.8%) than in duodenal varices (73.4%). The patient outcome did not differ among the various sites of the lesion. Conslusions:, Current status of ectopic varices in Japan has been clarified by a nationwide questionnaire survey. The authors expect that the pathophysiology of ectopic varices will be further elucidated, and that improved diagnostic modalities and treatment methods are established in the future. [source] Cholangiocarcinoma: preoperative biliary drainage (Con)HPB, Issue 2 2008A. LAURENT Aim. In patients with malignant hilar obstruction, liver resection is associated with an increased risk of postoperative liver failure attributed to the need for major liver resection in a context of obstructive jaundice. To overcome this issue, most authors recommend preoperative biliary drainage (PBD). However, PBD carries risks of its own, including, primarily, sepsis and, more rarely, tumor seeding, bile peritonitis, and hemobilia. We, unlike most authors, have not used routine PBD before liver resection in jaundiced patients. Material and methods. Our series includes 62 patients who underwent major liver resection for cholangiocarcinoma; 33 of these had elevated bilurubin (60,470 µmol/l) and were operated without PBD. There were 43 extended right hepatectomies and 18 extended left hepatectomies. Results. Hospital deaths occurred in 5 patients (8%) including 3 of 33 jaundiced patients (9%, ns). All deaths occurred after extended right hepatectomy (12%), including 3 patients with a serum bilirubin level above 300 µmol/l and 2 with normal bilirubin. There were no deaths after left-sided resections, whatever the level of bilirubin. Conclusions. PBD can be omitted in the following situations: recent onset jaundice (<2,3 weeks), total bilirubin <200 µmol/l, no previous endoscopic or transhepatic cholangiography, absence of sepsis, future liver remnant >40%. These criteria include most patients requiring left-sided resections and selected patients requiring right-sided resections. In other cases, PBD is required, associated with portal vein embolization in the event of a small future liver remnant. [source] Hilar cholangiocarcinoma: diagnosis and stagingHPB, Issue 4 2005William Jarnagin Cancer arising from the proximal biliary tree, or hilar cholangiocarcinoma, remains a difficult clinical problem. Significant experience with these uncommon tumors has been limited to a small number of centers, which has greatly hindered progress. Complete resection of hilar cholangiocarcinoma is the most effective and only potentially curative therapy, and it now clear that concomitant hepatic resection is required in most cases. Simply stated, long-term survival is generally possible only with an en bloc resection of the liver with the extrahepatic biliary apparatus, leaving behind a well perfused liver remnant with adequate biliary-enteric drainage. Preoperative imaging studies should aim to assess this possibility and must evaluate a number of tumor-related factors that influence resectability. Advances in imaging technology have improved patient selection, but a large proportion of patients are found to have unresectable disease only at the time of exploration. Staging laparoscopy and 13fluoro-deoxyglucose positron emission tomography (FDG-PET) may help to identify some patients with advanced disease; however, local tumor extent, an equally critical determinant of resectability, may be underestimated on preoperative studies. This paper reviews issues pertaining to diagnosis and preoperative evaluation of patients with hilar biliary obstruction. Knowledge of the imaging features of hilar tumors, particularly as they pertain to resectability, is of obvious importance for clinicians managing these patients. [source] Preoperative optimization of the liver for resection in patients with hilar cholangiocarcinomaHPB, Issue 4 2005Jacques Belghiti Optimal preoperative preparation is required to reduce operative risk of major hepatectomy in jaundiced patients. The role of percutaneous preoperative biliary drainage (PTBD) is, apart from assessment of intraductal extent of the tumour, to allow contralateral hypertrophy if portal vein embolization (PVE) is performed. The increased use of PTBD over a 10-year period was associated with increased resectability rate in this study, while PTBD-related complications decreased. Efficient hypertrophy of the future liver remnant (FLR) requires biliary drainage to reduce the risk of postoperative liver dysfunction. Preoperative staging laparoscopy avoided unnecessary surgical exploration in 20% of patients previously considered resectable. [source] Effect of Temperature on Fecundity, Life Span and Morphology of Long- and Short-Spined Clones of Brachionus caudatus f. apsteini (Rotifera)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 6 2008Sujiporn Athibai Abstract We investigated the effect of temperature (20, 25 and 30 °C) on fecundity, life span and morphology of the rotifer Brachionus caudatus f. apsteini. For each temperature, short posterior-spined and long posterior-spined clones of B. caudatus f. apsteini were individually cultured for up to six generations. The rotifers were fed Chlorella sp. at a density of 1 × 106 cells ml,1. Morphometric data (body size and spine length) were collected. Total number of offspring producing by a single female per life cycle at high temperature was higher than at low temperature. The duration of juvenile period, reproductive period, post-reproductive period and life span of both clones of B. caudatus f. apsteini decreased with increasing temperature. All offspring of short posterior-spined clone produce posterior spines at 20 and 25 °C, with an average length of 19.8 ± 6.6 and 11.9 ± 2.6 ,m, respectively. In contrast, they cannot develop posterior spines at 30 °C, at which the average length of the posterior spine remnant was 6.4 ± 1.3 ,m. On the other hand, all offspring of long posterior-spined clone have long posterior spines with average lengths of 36.8 ± 6.1, 36.3 ± 5.2 and 36.6 ± 6.2 ,m at 20, 25 and 30 °C, respectively. This study indicated that the production of posterior spines can be induced by low temperature and that short posterior-spined and long posterior-spined clones are genetically different. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Paraspermatogenesis in Littoraria (Palustorina) articulata, with reference to other Littorinidae (Littorinoidea, Caenogastropoda)INVERTEBRATE BIOLOGY, Issue 3 2000John A. Buckland-Nicks Abstract. The ultrastructure of paraspermatogenesis is examined in the littorinid subfamily Littorininae, with special emphasis on Littoraria (Palustorina) articulata (PHILIPPI 1846). In particular the study focuses on the fate of the nucleus and origin of the rod bodies during parasperm development. Parasperm of the Littorininae are rounded or oblong cells, which undergo an abortive meiosis and eliminate part of the nucleus but often retain a nuclear remnant. The cytoplasm is filled with numerous spherical vesicles in all Littorininae, but in Littoraria (and in certain species of Nodilittorina, Tectarius and Cenchritis) dense ,rod-bodies' also occur. Littoraria (Palustorina) are unique in possessing a flagellum-like structure termed the ,pseudotrich", which lacks an axoneme but contains microtubules during its development. Paraspermatogonia differ from euspermatogonia in the structure of the nucleus and in the extensive rough endoplasmic reticulum (RER) and swollen cytoplasm. Two types of secretions develop in Littoraria: (1) numerous, spherical granules (composed of putative glycoprotein, also seen in other Littorininae) and (2) rhomboid granules (composition uncertain but reacting positively to RNA stains; these granules arising within RER cisternae close to the nucleus). As the rhomboid granules fuse to form the larger, rod-bodies (polygonal in cross section), the RER membrane enclosing the rod-bodies becomes confluent with the outer nuclear membrane, thereby forming a common compartment. Results of this study clearly show that the rod-bodies are secretions of the RER cisternae and not, as claimed in some light microscopic accounts, the product of fusion of eusperm nuclei which have entered the parasperm cytoplasm (either by active eusperm penetration or by phagocytosis). Developmental characteristics of littorinid parasperm show differences between species and may, in some cases, provide characters diagnostic of subgenera. [source] Explaining bird species composition and richness in eucalypt-dominated remnants in subhumid TasmaniaJOURNAL OF BIOGEOGRAPHY, Issue 9 2003Michael A. MacDonald Abstract Aim To determine the factors influencing the distribution of birds in remnants in a fragmented agricultural landscape. Location Forty-seven eucalypt remnants and six sites in continuous forest in the subhumid Midlands region of Tasmania, Australia. Methods Sites were censused over a two-year period, and environmental data were collected for remnants. The avifauna of the sites was classified and ordinated. The abundances of bird species, and bird species composition, richness, abundance and diversity were related to environmental variables, using simple correlation and modelling. Results There were two distinct groups of sample sites, which sharply differed in species composition, richness, diversity and bird abundance, separated on the presence/absence of noisy miner (Manorina melanocephala Latham) colonies, remnant size, vegetation structural attributes and variables that reflected disturbance history. The approximate remnant size threshold for the change from one group to another was 20,30 ha. Remnant species richness and diversity were most strongly explained by remnant area and noisy miner abundance, with contributions from structural and isolation attributes in the second case. Segment richness was explained by precipitation, logging history and noisy miner abundance. Bird abundance was positively related to precipitation and negatively related to tree dieback. The 28 individual bird species models were highly individualistic, with vegetation structural variables, noisy miner abundance, climatic variables, variables related to isolation, area, variables related to floristics, disturbance variables, the nature of the matrix and remnant shape all being components in declining order of incidence. Age of the remnant did not relate to any of the dependent variables. Main conclusions Degraded and small remnants may have become more distinct in their avifaunal characteristics than might otherwise be the case, as a result of the establishment of colonies of an aggressive native bird, the noisy miner. The area, isolation and shape of remnants directly relate to the abundance of relatively few species, compared to vegetation attributes, climate and the abundance of the noisy miner. The nature of the matrix is important in the response of some species to fragmentation. [source] Can invasion patches of Acacia mearnsii serve as colonizing sites for native plant species on Réunion (Mascarene archipelago)?AFRICAN JOURNAL OF ECOLOGY, Issue 3 2009J. Tassin Abstract There is need for documenting the long-term effects of plant invasions at the landscape scale. We investigated the possible catalytic effect of invasive Acacia mearnsii De Wild. on the colonization of rural landscapes by native plant species on Réunion Island (Mascarene Archipelago, Indian Ocean). Data were recorded from 182 circular plots of 50 m2 within a set of 48 large invasion patches, aged from 1 to 48+ years. Only eighteen native plant species were present in the invaded patches and these in only 21 of the 48 patches. The Acacia invasion patches colonized by native flora were older and closer to the closest forest remnant. Most invasion patches colonized by native species were located <200 m from forest remnants. Results are consistent with studies on colonization rates of nonindigenous forest plantations, which increase with age and decrease with distance to seeds sources. Yet, the rate of Acacia invasion patches colonized by native flora remained very low compared to studies on the colonization of exotic plantations in other tropical countries. We conclude that invasion patches of Acacia mearnsii are poor colonizing sites for native plant species. Allelopathy is suspected as one of the strongest factors, which prevent this colonization. Résumé Il est nécessaire de documenter les effets à long terme des invasions de plantes à l'échelle du paysage. Nous avons étudié l'effet potentiellement catalyseur de la plante invasive Acacia mearnsii De Wild. sur la colonisation de paysages ruraux par des espèces végétales natives sur l'île de la Réunion (archipel des Mascareignes, océan Indien). On a récolté des données sur 182 parcelles circulaires de 50 m2 dans un ensemble de 48 grandes zones envahies âgées de un à plus de 48 ans. Il n'y avait que 18 espèces végétales natives dans les endroits envahis, et celles-là ne se trouvaient que dans 21 des 48 zones. Les zones envahies par les Acacia qui étaient colonisées par des espèces natives étaient plus âgées et se situaient plus près des reliquats forestiers les plus fermés. La plupart des zones envahies colonisées par des espèces natives étaient situées à moins de 200 m de forêts relictuelles. Les résultats sont cohérents avec des études sur les taux de colonisation de plantations forestières non indigènes, qui augmentent avec l'âge et diminuent avec la distance de la source des semences. Ceci dit, le taux de zones envahies par les acacias qui sont colonisées par la flore indigène reste très faible en comparaison avec les études sur la colonisation de plantations exotiques dans d'autres pays tropicaux. Nous concluons que les zones d'invasion d'Acacia mearnsii sont des sites de colonisation médiocre pour les espèces végétales indigènes. On suspecte que l'allélopathie est un des facteurs les plus actifs dans la prévention de cette colonisation. [source] Age and size compositions, growth and reproductive biology of the breaksea cod Epinephelides armatus, a gonochoristic serranidJOURNAL OF FISH BIOLOGY, Issue 5 2007S. E Moore Details of the reproductive biology, size and age compositions and growth of the breaksea cod Epinephelides armatus, the sole representative of Epinephelides, were obtained by collecting monthly samples of a wide total length (LT) range of individuals from coastal marine waters at 31,32° S on the lower west coast of Australia. Although the modal LT class of females (250,299 mm) was markedly less than that of males (400,449 mm), the modal ages of the two sexes were similar, i.e. 4 v. 5 years, respectively. The similarity in the age compositions and the histological demonstration that the gonads of all E. armatus consist solely of either ovarian or testicular tissues demonstrate that this species is gonochoristic, which is highly unusual for an anthiinine serranid. The absence of a central, membrane-lined ,ovarian' lumen in the testes of juveniles would account for adult testes containing neither this ovarian remnant nor the peripherally located sperm sinuses that are found in the mature testes of almost all other serranids. The results demonstrate that E. armatus exhibits a very unusual pattern of sexual development for a serranid. The spawning period of E. armatus lasts for c. 9 months, which is long for a species in temperate Western Australian waters, but comparable with that of many other relatively small serranids elsewhere. Females grow slower than males, attaining LT at 3, 5 and 10 years of c. 200, 285 and 420 mm, respectively, compared with c. 215, 315 and 450 mm, respectively. Females, however, attain maturity at a greater LT and older age than males. [source] Risk of gastric cancer is not increased after partial gastrectomyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7 2000R Bassily Abstract Background: It has been suggested that there is an increased risk of gastric cancer following partial gastrectomy. This question has not been studied in an Australian population. Methods: The records of a total of 569 patients who had a partial gastrectomy for peptic ulcer disease at Repatriation General Hospital, Heidelberg, between 1957 and 1976 were reviewed. All were followed to date of death or 31 December 1996. The expected rate of gastric cancer for this population was estimated from published Australian age-and sex-specific gastric cancer mortality rates over this period, and a standardized incidence ratio was calculated. Results: The mean age at surgery was 53.5 years (range 27,83 years). There were 547 male (96.4%) and 22 female (3.6%) patients. Five hundred and seven (83.5%) had a Billroth II procedure. Thirty-eight patients (6.3%) were lost to follow up and were not included in the analysis. From the records of the Department of Veterans' Affairs, it was established that 125 (20.6%) were alive in December 1996, a mean survival after surgery of 18.8 years. The mean documented duration of follow up was 17.3 years (range 1,41 years). Nine patients developed cancer in the gastric remnant. The expected number of cancers in this population was 6.5. Assuming all survivors were free of gastric cancer, the standardized incidence ratio was 1.39 (95% confidence intervals 0.64,2.65, P = 0.313). Conclusion: The risk of gastric cancer was not increased after partial gastrectomy in this Australian population. [source] MRA of intracranial aneurysms embolized with platinum coils: A vascular phantom study at 1.5T and 3TJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Shingo Kakeda Abstract Purpose To analyze the influence of matrix and echo time (TE) of three-dimensional time-of-flight (3D TOF) magnetic resonance angiography (MRA) on the depiction of residual flow in aneurysms embolized with platinum coils at 1.5T and 3T. Materials and Methods A simulated intracranial aneurysm of the vascular phantom was loosely packed to maintain the patency of some residual aneurysmal lumen with platinum coils and connected to an electromagnetic flow pump with pulsatile flow. MRAs were obtained altering the matrix and TE of 3D TOF sequences at 1.5T and 3T. Results The increased spatial resolution and the shorter TE offered better image quality at 3T. For the depiction of an aneurysm remnant, the high-spatial-resolution 3T MRA (matrix size of 384 × 224 and 512 × 256) with a short TE of ,3.3 msec were superior to the 1.5T MRA obtained with any sequences. Conclusion 3T MRA is superior to 1.5T MRA for the assessment of aneurysms embolized with platinum coils; the combination of the 512 × 256 matrix and short TE (3.3 msec or less) seems feasible at 3T. J. Magn. Reson. Imaging 2008;28:13,20. © 2008 Wiley-Liss, Inc. [source] Mineralized dermal layer of the Brazilian tree-frog Corythomantis greeningiJOURNAL OF MORPHOLOGY, Issue 1 2001E. Katchburian Abstract Some species of anuran amphibians possess a calcified dermal layer (the Eberth-Kastschenko layer) located between the "stratum spongiosum" and the "stratum compactum." This layer consists of calcium phosphate deposits, proteoglycans, and glycosaminoglycans. Although regarded as a protective layer against desiccation, a calcium reservoir, or possibly a remnant of a dermal skeleton present in anuran ancestors, very little is known about its origin, structure, and function. Thus, we studied the structure and composition of the mineralized dermal layer of Corythomantis greeningi, a peculiar hylid from the Brazilian semiarid region (caatinga), using conventional and cryosubstitution methods combined with transmission, scanning, and analytical electron microscopy. Results show that the dermal layer consists of dense, closely juxtaposed, globular structures. Although the electron opacity of the globules was variable, depending on the type of preparation, crystal-like inclusions were present in all of them, as confirmed by dark field microscopy. Electron probe X-ray microanalysis showed calcium, phosphorus, and oxygen, and electron diffraction revealed a crystalline structure comparable to that of a hydroxyapatite. J. Morphol. 248:56,63, 2001. © 2001 Wiley-Liss, Inc. [source] Primary reconstruction of small mandibular defects by using mandibular remnant,JOURNAL OF SURGICAL ONCOLOGY, Issue 7 2006FRCS(Glasg), FRCSEd, Kumar Alok Pathak MS, MNAMS No abstract is available for this article. [source] | |||||||||||||||||||||||||||||||||||||||||||