bluuebunny/crossref_metadata_2025_split huggingface dataset:
The functional anatomy of the mantle cavity, kidney and blood system of some pilid gastropods (Prosobranchia)
Authors: Andrews Elizabeth B. 
Published: May 2010

This account is the result of investigations on living and preserved specimens of Pomacea canaliculata as well as preserved specimens of Pila globosa, Turbinicola saxea and Lanistes ovum bangweolicus.Pilids are amphibious prosobranchs with both a lung and a ctenidium in the mantle cavity. The mantle cavity is broad and shallow, and in addition to the normal pallial complex in these there is a highly extensible pallial inhalant siphon on the left of the head, allowing ventilation of the lung under water, and a fold bordering a longitudinal groove to the right of the head, similar to that in viviparids which creates a separate exhalant channel leading to a samll exhalant siphon. the ctenidium is displaced by the lung to the right and its small leaflets are curved so that they overhang the pallial groove. The hypobranchial gland to the right of the ctenidium extends over the wall of the rectum and genital duct along the right side of the groove.Blood is carried to the lung by the extension of the afferent ctenidial vein and drained from it by the efferent ctenidial vein. In Pomacea an additional afferent vein to the floor of the lung is apparently developed by the horizontal division of the efferent ctenidial vein. To maintain an ample supply of blood at high pressure to the respiratory organs the visceral vein leads directly on to the mantle skirt and has lost its connection with the afferent renal vein. This results in a highly vascular mantle skirt so that a large volume of blood would be forced into the heart on retraction of the snail into its shell; to accommodate this a highly extensible ampulla is developed on the anterior aorta within the pericardial cavity.The kidney, like that of other freshwater prosobranchs, is complex and contains an accessory chamber, overlying the posterior part of the mantle cavity, and which appears to be mesodermal in origin. It is much folded and highly vascular, and is supplied by the afferent renal vein and the renal nerve. The epithelium of the chamber excretes some purines other than uric acid as very fine spherules, whereas in the posterior part of the kidney, large concretions containing uric acid are built up. Blood from the anterior chamber drains into the afferent ctenidial vein; the efferent vessel of the posterior chamber is the homologue of the efferent nephridial vein, although the nephridial gland itself is vestigial. The efferent renal vein to the mantle skirt, which is present in other prosobranchs, has lost its connection with the visceral part of the kidney in pilids.
Masticatory function and skull growth
Authors: Moore W. J. 
Published: May 2010

A diminution in function of the masticatory muscles of the rat was produced by feeding upon an abnormally soft diet. As compared with a control group fed on a hard diet, this resulted in a 12% decrease in the mass of the cranium and mandible together with a reduction of some 1 to 2% in the overall dimensions of the cranial and facial skeleton. This contrasted with a decrease of some 4% in the length of the angular process of the mandible which is specifically associated with muscular insertion.The differences in cranial dimensions of the two groups of rats were unlikely to have resulted from differences in overall body weight.
Evidence for the existence of a new subspecies of Chaetogaster limnaei (Oligochaeta), in Britain
Authors: Gruffydd Ll. D. 
Published: May 2010

A study of two distinct forms of Chaetogaster limnaei (Baer) was carried out in a population of Lymnaea pereger. One form inhabits the kidney of freshwater snails and the other lives on the external surface of these molluscs. Various differences between the two forms were studied.The outer form possesses a significantly greater number of setae per bundle than the kidney form and those of the kidney form are also shorter than those of the outer form. The stomach and intestinal epithelia are considerably thicker in the outer form than in the kidney form.The contents of the stomach and intestine of both forms was recorded from samples taken over a period of 12 months. It was seen that whilst the outer form fed on various planktonic organisms, the kidney form fed exclusively on cells derived from the kidney. Kidney forms would not under any of the experimental conditions feed on the planktonic organisms normally taken by the outer form.Both forms were found to be specific in their habitat in that if removed from their host and introduced to another, kidney forms always colonized the kidney and outer forms always remained on the outer surface. Neither lack of planktonic food nor conditions of drought could induce the outer forms to enter the kidney.Both forms showed a positive reaction to the mucus of their host but that of the outer form was by far the most pronounced. It was shown that the mucous trail left by the host snail assisted the outer form in finding a new host in that if the right direction was taken initially it would follow this trail, overhaul the snail and attach itself to it. The outer form also had greater ability to survive free living than the kidney form. Outer forms were kept alive for a maximum of seven weeks and kidney forms for only three weeks.It was suggested that the kidney form be considered a subspecies of Chaetogaster limnaei and that it be known as Chaetogaster limnaei vaghini. A brief description of the new subspecies is given.
On the placentation of Tupaia
Authors: Hill J. P. 
Published: May 2010

The placentation of Tupaia is of particular interest for two main reasons, first because of the suggested relationship of the Tree shrews (Tupaiidae) to the Lemuroidae—a relationship which has been much discussed and on which widely divergent views have been expressed—and second because Tupaia is the only mammal so far described in which the foetus is provided with a double (so called bidiscoidal) placenta of the entothelial chorial type.The placental sites are easily recognizable in the virgin uterus as two localized areas of the endometrium, respectively dorsal and ventral, and characterized by the absence of uterine glands. On pregnancy supervening the endometrium of each site undergoes a marked decidual reaction forming the maternal component of (1) a temporary omphalopleural (yolk sac) placenta—the foetal component of which is furnished by the vascular omphalopleure—and of (2) the definitive allantoic placenta. The allantois growing down as a flattened lobe on either side and penetrating between the attached trophoblast of the vascular omphalopleure and its mesodermal and endothelial layers ensuring the replacement of the vitelline vessels of the vascular omphalopleure by the allantoic vessels and thus forming a relatively simple labyrinthine endothelio chorial placenta.
Early development of the head and pharynx ofNeoceratoduswith a consideration of its phylogeny
Authors: Fox Harold 
Published: May 2010

The development of the head and pharynx of larvae ofNeoceratodus(ranging in length from 11.5 to 34. 5 mm) was investigated form microscopic transverse serial sections. The structures studied included the chondrocranium and visceral arches, ossifications, cranial and anterior spinal nerves, musculature and vascular system. These components ofNeoceratodusare compared with similar ones, likewise investigated, inRana temporariaandRana esculenta(33 and 26 mm long, respectively), and in various genera of Urodela, either previously investigated by the author or by reference to the earlier literature.Some new homologues of the various morphological components of the head and pharynx of these groups are suggested.On the basis of the larval structure an assessment is made of the classical view of a close phylogenetic relationship betweenNeoceratodusand the two amphibian groups. it is concluded that they share a common derivation from pro‐dipnoan‐amphibian stock—of crossopterygian ancestry—in the early Devonian: a conclusion which supports an earlier somewhat similar view of Goodrich.It is further considered that there is evidence of a quasi parallel evolution betweenNeoceratodusand Urodela, though some assumed similarities in larval structure are spurious; nevertheless, in some ways, they are more similar than areNeoceratodusand members of the Anura.A common origin ofNeoceratodus(Dipnoi) and the amphibian groups supports the vie of a monophyletic derivation of the Tetrapoda.
The Muridae of Malawi (Africa: Nyasaland)
Authors: Hanney Peter 
Published: May 2010

Information upon the distribution and biology of the Muridae occurring in Nyasaland (now the Malawi Republic) was obtained mainly from collections made between February 1962 through June 1963, when a total of 13,190 trap nights and 4417 trap days were expended. Approximations of relative abundance in various areas were made by using standard trap lines. Species only recorded in areas with mean annual rainfall at least 60 inches were Lophuromys flavopunctatus, Praomys jacksoni and Thamnomys cometes. Mus triton was unrecorded in areas with mean annual rainfall less than 38 inches. The greatest biomass was trapped on high rainfall plateaux where predominant species trapped were campestrial and insectivorous. In other areas, species predominant in traps were mainly fossorial and vegetarian. In 78% of the localities examined, one or two species comprised over 65% of the catch.Some details of the bionomics and breeding biology of the common species were elucidated by regular collections in selected areas throughout the annual cycle. Species studied in detail were found to have a reproductive peak during the wet or the first half of the dry season. Males were consistently larger than females excepting in T. cometes, sexual size differences were statistically significant in several species. Of the 32 species recorded, only four were purely vegetarian while six were mainly insectivorous.
Spatial and temporal variation in population trends in a long‐distance migratory bird
Authors: Morrison Catriona A. , Robinson Robert A. , Clark Jacquie A. , Gill Jennifer A. 
Published: May 2010

AbstractAim  Over the past three decades, evidence has been growing that many Afro‐Palaearctic migratory bird populations have suffered sustained and severe declines. As causes of these declines exist across both the breeding and non‐breeding season, identifying potential drivers of population change is complex. In order to explore the roles of changes in regional and local environmental conditions on population change, we examine spatial and temporal variation in population trajectories of one of Europe’s most abundant Afro‐Palaearctic summer migrants, the willow warbler, Phylloscopus trochilus.Location  Britain and Ireland.Methods  We use national survey data from Britain and Ireland (BBS: BTO/RSPB/JNCC Breeding Bird Survey and CBS: BWI/NPWS/Heritage Council Countryside Breeding Survey) from 1994 to 2006 to model the spatial and temporal variation in willow warbler population trends.Results  Across Britain and Ireland, population trends follow a gradient from sharp declines in the south and east of England to shallow declines and/or slight increases in parts of north and west England, across Scotland and Ireland. Decreasing the spatial scale of analysis reveals variation in both the rate and spatial extent of population change within central England and the majority of Scotland. The rates of population change also vary temporally; declines in the south of England are shallower now than at the start of the time series, whereas populations further north in Britain have undergone periods of increase and decline.Main conclusion  These patterns suggest that regional‐scale drivers, such as changing climatic conditions, and local‐scale processes, such as habitat change, are interacting to produce spatially variable population trends. We discuss the potential mechanisms underlying these interactions and the challenges in addressing such changes at scales relevant to migratory species.
Elusive equilibrium: the challenge of interpreting receptor pharmacology using calcium assays
Authors: Charlton Steven J , Vauquelin Georges 
Published: May 2010

Calcium is a key intracellular signal that controls manifold cellular processes over a wide temporal range. The development of calcium‐sensitive fluorescent dyes and proteins revolutionized our ability to visualize this important second messenger and its complex signalling characteristics. The subsequent advent of high throughput plate‐based fluorescence readers has resulted in the calcium assay becoming the most widely utilized assay system for the characterization of novel receptor ligands. In this review we discuss common approaches to calcium assays, paying particular attention to the potential issues associated with interpretation of receptor pharmacology using this system. Topics covered include dye saturation and forced‐coupling of receptors to the calcium pathway, but special consideration is given to the influence of non‐equilibrium conditions in this rapid signalling system. Modelling the calcium transient in a kinetic mode allows the influence of ligand kinetics, receptor reserve and read time to be explored. This demonstrates that observed ligand pharmacology at very early time points can be quite different to that determined after longer incubations, even resulting in reversal of agonist potency orders that may be misinterpreted as agonist biased signalling. It also shows that estimates of antagonist affinity, whether by Schild analysis or inhibition curves, are similarly affected by hemi‐equilibrium conditions. Finally we end with a discussion on practical approaches to accurately estimate the affinity of insurmountable antagonists using calcium assays.LINKED ARTICLESThis article is part of a themed section on Analytical Receptor Pharmacology in Drug Discovery. To view the other articles in this section visithttp://dx.doi.org/10.1111/bph.2010.161.issue‐6
Cost‐effectiveness of Endoscopic Surveillance for Gastric Intestinal Metaplasia
Authors: Hassan Cesare , Zullo Angelo , Di Giulio Emilio , Annibale Bruno , Lahner Edith , De Francesco Vincenzo , Ierardi Enzo 
Published: May 2010

AbstractBackground:  Patients with intestinal metaplasia (IM) are at increased risk for gastric cancer. Endoscopic surveillance has been shown to anticipate cancer diagnosis in an earlier stage. Cost‐effectiveness of endoscopic surveillance in IM patients is unknown. To assess the efficacy and cost‐effectiveness of an yearly endoscopic surveillance in patients with IM.Methods:  A decision analysis model was constructed in order to compare a strategy of performing an EGD every year for a 10‐year period (surveillance strategy) following a new diagnosis of IM to a policy of nonsurveillance in a simulated cohort of 10,000 American patients. A 1.8% 10‐year cumulative incidence of gastric cancer in IM patients was estimated from the literature. Endoscopic surveillance was simulated to downstage the detected cancers by 58–84%. Costs of EGD and cancer care were estimated from Medicare reimbursement data. The main outcome measurement was the incremental cost‐effectiveness ratio.Results:  The number of EGDs required to detect one cancer and to prevent one gastric cancer‐related death in the surveillance arm were 556 and 3738, respectively. The incremental cost‐effectiveness ratio of endoscopic surveillance as compared to a nonsurveillance policy was $72,519 per life‐year gained (5–95% percentiles Monte Carlo analysis: $54,843–$98,853). At sensitivity analysis, cancer incidence and the rate of downstaging were the most important variables.Conclusions:  According to our simulation, the relatively high risk of cancer in patients with IM and the substantial efficacy of endoscopic surveillance in reducing cancer‐related mortality would support the cost‐effectiveness of an endoscopic surveillance program in patients with IM. Further research is needed before implementing it in the clinical practice.
Time Trends of Helicobacter pylori Resistance to Antibiotics in Children Living in Vienna, Austria
Authors: Vécsei Andreas , Kipet Andrea , Innerhofer Albina , Graf Ulrike , Binder Christa , Gizci Heidemarie , Hammer Karin , Bruckdorfer Andrea , Huber Wolf‐Dietrich , Hirschl Alexander M. , Makristathis Athanasios 
Published: May 2010

AbstractBackground:  Increase of antibiotic resistance is a worldwide problem. Within the 4 years before the turn of the millennium Helicobacter pylori strains isolated in children living in Vienna, Austria, showed a primary clarithromycin and metronidazole resistance of 20% and 16%, respectively. The aim of this retrospective follow‐up survey was to assess the further development and current antimicrobial resistance status.Methods:  Children having undergone upper endoscopy between March 2002 and March 2008 at the same two co‐operating pediatric gastroenterology units which had also been collaborating on the prior assessment were included. H. pylori infection was diagnosed by rapid urease test, histology, and culture. If the latter was positive, susceptibility testing to amoxicillin, clarithromycin and metronidazole by E‐test followed. From March 2004 onwards, susceptibility to levofloxacin, tetracycline and rifampin was additionally assessed.Results:  Out of 897 children, 153 had a proven infection with H. pylori and no history of prior eradication treatment. Their median age was 11.5 years (range 0.5–20.9 years). Primary resistance to clarithromycin and metronidazole were 34% and 22.9%, respectively; dual resistance was found in 9.8% of the strains; 0.9% was resistant to tetracycline and rifampin, respectively. No case of amoxicillin resistance was detected. The only independent risk factor for clarithromycin resistance turned out to be the origin of a child from Austrian parents.Conclusions:  In the last decade, the rate of primary resistance of H. pylori to clarithromycin continued to rise. No significant change was found regarding primary resistance to metronidazole or dual resistance to metronidazole and clarithromycin, respectively.
Development of Immunoreagents for Diagnostics of CagA‐Positive Helicobacter pylori Infections
Authors: Klimovich Alexander V. , Samoylovich Marina P. , Gryazeva Irina V. , Terekhina Lidiya A. , Suvorov Alexander N. , Klimovich Vladimir B. 
Published: May 2010

AbstractBackground:  Helicobacter pylori strains expressing cytotoxic CagA protein are more likely to provoke severe gastric mucosal pathology and cause adenocarcinoma development than that lacking CagA. Determination of the CagA‐status of a pathogen, therefore, is regarded as informative approach in H. pylori infection diagnostics and disease risk prediction.Materials and Methods:  Molecular cloning, recombinant protein expression in Escherichia coli, affinity chromatography, electrophoresis and commonly used techniques of hybridoma production and screening were used as well as different immunosorbent assays and Western blot procedures.Results:  Four overlapping N‐terminally His6‐tagged recombinant fragments of CagA that covered the entire CagA sequence were produced and purified. An ELISA for specific anti‐CagA serum antibodies detection was developed and evaluated. Utilizing recombinant fragments, the first set of monoclonal antibodies against CagA‐antigen was produced and characterized. Three antibodies recognized distinct linear epitopes inside conserved regions of the cytotoxin whereas the epitope of the forth antibody was mapped in the variable area of CagA. The monoclonal antibodies allowed discriminating CagA‐positive and CagA‐negative H. pylori strains by means of Western blot and immunosorbent assays.Conclusions:  The use of recombinant protein technology allowed obtaining pure CagA antigen, thus providing new perspectives for development of immunodiagnostic reagents. The set of monoclonal antibodies is a valuable tool for determination of CagA‐status of H. pylori infection and for the investigation of cytotoxin molecule as well.
Profile of Expression of Helicobacter pyloriγ‐Glutamyltranspeptidase
Authors: Wachino Jun‐Ichi , Shibayama Keigo , Suzuki Satowa , Yamane Kunikazu , Mori Shigetarou , Arakawa Yoshichika 
Published: May 2010

AbstractBackground:  Helicobacter pylori produces γ‐glutamyltranspeptidase (GGT), a potential virulence factor involved in induction of host cell apoptosis. Regulation of the production of this protein is not known.Methods:  The transcription start sites were determined by primer extension analysis. Transcription level of the GGT gene was examined by measuring the mRNA by RT‐PCR and expression level of GGT protein was examined by Western blot analysis under different conditions.Results:  Two transcription start sites were identified; thymine at 78‐bp upstream and adenine at 79‐bp upstream from the ATG codon of the GGT gene. There was a possible ‐10 consensus promoter sequence (ATTAAT), but no apparent ‐35 consensus sequence was found. The transcription of the mRNA and the expression of the protein were at almost constant level during the course of culture. The mRNA level increased by exposure to low pH; however, the actual protein expression level remained almost constant. Addition of glutamine or glutamate did not affect the mRNA level and the protein expression level to a remarkable degree, nor did co‐culture with AGS cells affect the GGT activity level.Conclusion:  It was suggested that H. pylori GGT is constitutively expressed under various conditions.
Endoscopic Tests for the Diagnosis of Helicobacter pylori Infection in Children: Validation of Rapid Urease Test
Authors: Roma‐Giannikou Eleftheria , Roubani Alkaterini , Sgouras Dionyssios N. , Panayiotou Joanna , Van‐Vliet Catherine , Polyzos Alexandros , Roka Kleoniki , Daikos George 
Published: May 2010

AbstractBackground:  Rapid urease test (CLO‐test) is an inexpensive and quick method for diagnosis of Helicobacter pylori infection with controversial results in children. We evaluated the performance of CLO‐test in relation to endoscopic and histological findings in children with H. pylori infection.Materials and methods:  We studied the medical records of children with H. pylori infection who were diagnosed between 1989 and 2009. Noninfected children were used as controls. H. pylori infection was defined by positive culture or by two other positive tests (histology and CLO‐test, or urea breath test when a single test was positive). All children had histology together with CLO‐test. Tissue culture was performed whenever possible.Results:  Five hundred thirty infected children (10.4 ± 3.0 years) and 1060 controls (7.3 ± 4.4 years) were studied. Sensitivity of CLO‐test was 83.4% (95% CI, 79.9–86.3%), of culture 84.6% (95% CI, 78.7–89.1%), of histology 93.2% (95% CI, 90.7–95.1%), and specificity 99% (95% CI, 98.2–99.4%), 100%, and 100% respectively. CLO‐test positivity was correlated with higher bacterial density (p < .001), activity (p < .001) and severity of gastritis (p < .01), older age (p < .01), and the presence of antral nodularity (p < .001). When CLO‐test was positive, the concordance with histology and culture was high (95.5 and 89.2% respectively), whereas low concordance was observed when CLO‐test was negative (17.05 and 45.83% respectively).Conclusions:  CLO‐test had lower sensitivity and comparable specificity with histology. Both tests should be performed concurrently to accurately diagnose H. pylori infection in children.