bluuebunny/crossref_metadata_2025 huggingface dataset:
Habitat use and trophic position determine mercury concentration in the straight fin barb Barbus paludinosus, a small fish species in Lake Awassa, Ethiopia
Authors: Desta Z. , Borgstrøm R. , Gebremariam Z. , Rosseland B. O.
Published: August 2008

The diet, habitat use and mercury concentration of the small fish species, the straight fin barb Barbus paludinosus, were studied in Lake Awassa, Ethiopia, for a period of 1 year from February 2003 to January 2004. Stable isotope signatures of nitrogen and carbon in different total length (LT) classes were used to determine trophic positions and organic carbon sources, respectively. Barbus paludinosus mainly occupied the protected benthic habitats (littoral and profundal) of the lake. The δ13C values were in the range from −24 to −19‰, indicating that the carbon source for B. paludinosus was benthic, as well. Small individuals (≤ 60 mm LT) mainly preyed upon ostracods, intermediate sizes (60–100 mm) on aquatic insects and gastropods, while a tiny cyprinodont fish Aplocheilichthys antinorii dominated the diet of large individuals (100–160 mm). The progressively increase in δ15N with increasing LT also indicated a diet shift towards piscivory in larger individuals. The mercury concentration ranging from 0·02 to 0·74 mg kg−1 wet mass (wm), was unexpectedly high in this small species, and was significantly positively related to LT, as well as to δ15N. Some large individuals had mercury concentrations < 0·1 mg kg−1 wm, and low δ15N, indicating substantial variations in diet between individuals of same size. The study suggests that other piscivorous species which include B. paludinosus in their diet may have a high mercury intake risk.
Age and growth of the round stingray Urobatis halleri at Seal Beach, California
Authors: Hale L. F. , Lowe C. G.
Published: August 2008

The age and growth of the round stingray Urobatis halleri was determined using vertebral sections from animals collected at Seal Beach, California from 2002 to 2005. Annual periodicity was validated from U. halleri injected with oxytetracycline and maintained in captivity over a 2 year period (n= 7). The coefficients estimated by the von Bertalanffy growth model were the disc width asymptote (WD∞) (286 mm for males and 224 mm for females) and K (0·09 year−1 for males and 0·15 year−1 for females). The age structure of the population consisted of mostly older, mature males and females. Age at maturity was estimated at 3·80 years for females and 3·75 years for males, and the maximum assessed age was 14 years old. Males were more numerous than females throughout the year; however, from May to September, females outnumbered males. The U. halleri age and growth coefficients were comparable to other species in the family Urolophidae. Based on the seasonality and age structure of this population, Seal Beach offers warm‐water refuge for U. halleri of reproductive maturity, and the U. halleri at Seal Beach may garner some behavioural thermoregulation benefit.
Information from a pregnant salmon shark Lamna ditropis in the eastern North Pacific with observations on oophagous reproduction
Authors: Gallucci V. F. , Foy R. J. , O’Brien S. M. , Aires‐da‐Silva A. , Nesse H. , Langseth B. , Vega N. , Taylor I. , Goldman K. J.
Published: August 2008

A pregnant salmon shark Lamna ditropis, captured in Alaska in December 2006, held two male and two female oophagous embryos (two per uterus) nourished by a single large 7·5 kg ovary. This discovery provides new data and insights into reproduction of the species and new perspective on the genus Lamna.
Site fidelity and seasonal changes in activity centre size of female pike Esox lucius in a small lake
Authors: Kobler A. , Klefoth T. , Arlinghaus R.
Published: August 2008

The object of this study was to test site fidelity of female pike Esox lucius and to contrast the activity centre size in summer and winter in a 25 ha lake in north‐eastern Germany using radio telemetry. Weekly 24 h tracking and two 96 h tracking exercises were conducted by boat from June to December 2005 and by walking on surface ice from January to February 2006. Positions of 12 E. lucius [total length (LT) = 450–733 mm] were recorded every 3 h within a 24 h tracking cycle. Site fidelity to individual summer activity centres was tested by translocating eight E. lucius away from their activity centre. All translocated E. lucius returned to their summer activity centre within 6 days, which provided evidence of site fidelity of E. lucius. There was no relation between E. luciusLT or the translocation distance and return time to the activity centre after translocation. In winter, the activity centre size of E. lucius was significantly larger than in summer, but there was considerable overlap between the sites chosen in winter and those in summer. The seasonal variation in activity centre size possibly reflected changes in habitat structure (e.g. collapse of structured vegetated habitats in winter) or prey fish distribution.
Enzymatic and mitochondrial responses to 5 months of aerial exposure in the slender lungfish Protopterus dolloi
Authors: Staples J. F. , Kajimura M. , Wood C. M. , Patel M. , Ip Y. K. , McClelland G. B.
Published: August 2008

Mitochondrial respiration and activities of key metabolic enzymes from liver and white skeletal muscle were compared between control aquatic slender lungfish Protopterus dolloi, and those exposed to air for 5 months. Activities of citrate synthase, glycogen phosphorylase, phosphofructokinase and pyruvate kinase in liver were not affected by air‐exposure. In muscle, air‐exposure reduced citrate synthase and pyruvate kinase activities (relative to tissue wet mass) by 63 and 50%, respectively. Liver carnitine palmitoyl transferase activity (relative to mitochondrial protein) decreased by half following air‐exposure, but there was no change in muscle. In mitochondria isolated from muscle, state 3 and state 4 respiration were reduced by 74 and 89%, respectively following air‐exposure, but liver mitochondria were not affected. In liver, air‐exposure increased activities of ornithine‐urea cycle enzymes including glutamine synthase, carbamoyl‐phosphate synthase III and arginase, by 1·9‐ to 4·2‐fold. Carbamoyl‐phosphate synthase III activity could not be detected in muscle, indicating that urea is not synthesized in this tissue. These data suggest that skeletal muscle metabolism is downregulated in air‐exposure, conserving energy and protein during a period when the animals cannot forage. In contrast, ATP production capacities in the liver are maintained, and this may permit expensive urea biosynthesis to continue during aerial exposure.
The threadfin bream Nemipterus randalli (Perciformes: Nemipteridae) in the eastern Mediterranean Sea
Authors: Lelli S. , Colloca F. , Carpentieri P. , Russell B. C.
Published: August 2008

A total of 30 specimens (73–95 mm standard length) of Nemipterus randalli were collected along the Lebanon coast. This species, a Lessepsian migrant previously misidentified as Nemipterus japonicus, appears to be well established in the Levantine basin of the Mediterranean Sea. The small size and immature status of the specimens of N. randalli collected from the Lebanon coast indicate recent successful recruitment.
Losing ‘Nemo’: bleaching and collection appear to reduce inshore populations of anemonefishes
Authors: Jones A. M. , Gardner S. , Sinclair W.
Published: August 2008

Surveys of anemonefishes (Amphiprioninae) were conducted on reefs in two regions of the Great Barrier Reef Marine Park with contrasting histories of disturbance to determine the degree to which spatial variation might be explained by bleaching or management status. Densities of anemonefishes were lower on reefs in the bleaching‐impacted Keppel Islands than on reefs in Far North Queensland. No anemonefishes or anemones were found on or near bleached corals in the Keppel Islands. Furthermore, the highest densities of fishes were found on reefs closed to fishing and aquarium collecting in both the Keppel Islands and Far North Queensland, which suggests that collecting is compounding the effects of bleaching. These results emphasize the importance of understanding the interaction between bleaching events and anthropogenic disturbance upon commercially exploited species.
A comparison of nest building by three‐spined sticklebacksGasterosteus aculeatusfrom still and flowing waters
Authors: Rushbrook B. J. , Barber I.
Published: August 2008

The composition of nests, built under standardized, static laboratory conditions by male three‐spined sticklebacksGasterosteus aculeatusfrom two rivers and two lakes in mid‐Wales (U.K.) was quantified. After transfer to nesting tanks, fish from the rivers began building nests more quickly than fish from the lakes. The number of threads used in nest construction and the mass of substrate deposited co‐varied, but there were no consistent population‐ or habitat‐related differences in the aspects of nest composition.
Effects of cadmium chloride on the development of rainbow trout Oncorhynchus mykiss early life stages
Authors: Lizardo‐Daudt H. M. , Kennedy C.
Published: August 2008

The sub‐chronic (28–56 days) effects of exposure to low concentrations of cadmium (Cd; 0·05, 0·25, 0·50 and 2·50 μg l−1) shortly following fertilization on embryos, larvae and juvenile rainbow trout Oncorhynchus mykiss were examined. Premature hatching occurred at lower concentrations (0·05 and 0·25 μg l−1 Cd), however, delayed hatching was seen in the 2·50 μg l−1 Cd group, with >90% of hatching occurring on the last day of the hatching period. Larval growth was negatively affected by Cd exposure in a concentration‐dependent manner. Larvae exposed to 2·50 μg l−1 Cd were 13·9 ± 0·8% shorter in total length (LT) and weighed 22·4 ± 3·5% (mean ±s.e.) less than controls at the end of the exposure period. Plasma sex steroid concentrations (oestradiol in juvenile females and 11‐ketotestosterone in juvenile males) were elevated (four‐ to 10‐fold over controls) in exposed fish in both males and females, following 28 days of exposure to 0·05, 0·25 and 0·50 μg l−1 Cd, respectively. These results suggest that environmentally realistic concentrations (in the μg l−1 range) of Cd can affect the development of O. mykiss impacting embryos, larvae and juvenile fish.
Cd52, known as a major maturation‐associated sperm membrane antigen secreted from the epididymis, is not required for fertilization in the mouse
Authors: Yamaguchi Ryo , Yamagata Kazuo , Hasuwa Hidetoshi , Inano Emiko , Ikawa Masahito , Okabe Masaru
Published: August 2008

CD52 is a glycosylphosphatidylinositol (GPI)‐anchored antigen expressed on lymphocytes and in epididymal epithelial cells. CD52 is also known as “maturation‐associated sperm antigen” but its function is unknown. We therefore generated Cd52 disrupted mice. The resulting Cd52 null mice were healthy, even though Cd52 is expressed on cells of the immune system. We then examined a possible role for CD52 in reproduction. Sperm from Cd52‐deficient males were investigated and the viability, motility, morphology, and incidence of spontaneous acrosome reactions were found to be all similar to values for wild‐type sperm. In in vitro fertilization system, the sperm showed normal fertilizing ability. As CD52 was found to be transferred onto sperm only after they had migrated into the vas deferens, we examined the behavior of sperm from Cd52‐deficient mice in vivo. The mice mated naturally and we observed that a normal number of sperm passed through the uterotubal junction, known to the crucial hurdle for various gene knockouts resulting in infertile sperm. As a consequence, there was no difference in the litter size from the wild‐type and Cd52‐null males. Our results therefore indicate CD52 is not required for fertilization in the mouse either in vivo or in vitro.
Member of the membrane‐bound O‐acyltransferase (MBOAT) family encodes a lysophospholipid acyltransferase with broad substrate specificity
Authors: Matsuda Shinji , Inoue Takao , Lee Hyeon‐Cheol , Kono Nozomu , Tanaka Fumiharu , Gengyo‐Ando Keiko , Mitani Shohei , Arai Hiroyuki
Published: August 2008

Glycerophospholipids in biological membranes are metabolically active and participate in a series of deacylation–reacylation reactions, which may lead to accumulation of polyunsaturated fatty acids (PUFAs) at the sn‐2 position of the glycerol backbone. The reacylation reaction is believed to be catalyzed by acyl‐coenzyme A (acyl‐CoA):lysophospholipid acyltransferase. Very recently, we have shown that Caenorhabditis elegans mboa‐7, which belongs to the membrane‐bound O‐acyltransferase (MBOAT) family, encodes lysophosphatidylinositol (LPI)‐specific acyltransferase (LPIAT). In this study, we found that knockdown of another member of the MBOAT family in C. elegans, named mboa‐6, reduced incorporation of exogenous PUFAs into phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylethanolamine (PE) in C. elegans. Knockdown of a human mboa‐6 homologue, referred to as MBOAT5, also impaired the incorporation of PUFAs into PC, PS and PE in HeLa cells. In in vitro assays, lysoPC (LPC), lysoPS (LPS) and lysoPE (LPE) acyltransferase activities using [14C]arachidonoyl‐CoA were significantly reduced in the microsomes of MBOAT5 knockdown cells. Conversely, over‐expression of MBOAT5 in human embryonic kidney (HEK) 293 cells resulted in great increases in LPC, LPS and LPE acyltransferase activities but not in LPIAT or lysophosphatidic acid (LPA) acyltransferase (LPAAT) activities. These results indicate that human MBOAT5 is a lysophospholipid acyltransferase acting preferentially on LPC, LPS and LPE.
Tissue residue depletion of oxytetracycline after repeated intramuscular administration of Oxysentin 100 in sheep
Authors: FLETOURIS D. J. , PAPAPANAGIOTOU E. P.
Published: August 2008

The depletion profile of oxytetracycline was studied in healthy sheep after intramuscular administration of Oxysentin 100, given at a dose of 10 mg oxytetracycline per kg body weight once daily for 5 consecutive days. Five medicated sheep were slaughtered at 0, 2, 4, 6, 9 and 12 days postmedication, and injection site, muscle, fat, liver and kidney tissues were sampled and analysed using a liquid chromatographic method, which was fully validated for oxytetracycline and 4‐epi‐oxytetracycline. At day 0 postmedication, the concentrations of oxytetracycline marker residue (sum of oxytetracycline and 4‐epi‐oxytetracycline) in all tissues examined were at the mg/kg level. At day 2 postmedication, the concentrations of oxytetracycline marker residue in all injection site and kidney samples examined were higher than the corresponding maximum residue limits (MRLs) established by the European Union, while the concentrations in muscle and liver tissues of two and three out of five animals examined, respectively, were below the corresponding MRLs. At days 4 and 6 postmedication, concentrations of oxytetracycline marker residue above the MRLs were found only in the injection site, whereas at day 9 postmedication, all observations were below the corresponding MRLs.
Fast, transient and specific intracellular ROS changes in living root hair cells responding to Nod factors (NFs)
Authors: Cárdenas Luis , Martínez Adán , Sánchez Federico , Quinto Carmen
Published: August 2008

The role of reactive oxygen species (ROS) in root‐nodule development and metabolism has been extensively studied. However, there is limited evidence showing ROS changes during the earliest stages of the interaction between legumes and rhizobia. Herein, using ratio‐imaging analysis, increasing and transient ROS levels were detected at the tips of actively growing root hair cells within seconds after addition of Nod factors (NFs). This transient response (which lasted up to 3 min) was Nod‐factor‐specific, as chitin oligomers (pentamers) failed to induce a similar response. When chitosan, a fungal elicitor, or ATP was used instead, a sustained increasing signal was observed. As ROS levels are transiently elevated after the perception of NFs, we propose that this ROS response is characteristic of the symbiotic interaction. Furthermore, we discuss the remarkable spatial and temporal coincidences between ROS and transiently increased calcium levels observed in root hair cells immediately after the detection of NFs.
Transgressive segregation for phenological traits in barley explained by two major QTL alleles with additivity
Authors: Castro A. J. , Hayes P. , Viega L. , Vales I.
Published: August 2008

Quantitative trait loci (QTL) analysis can contribute to a deeper understanding of crop phenology. The parents of a barley mapping population have similar growth and development profiles, but the progeny show transgressive segregation for phenological traits. These phenotypes were measured in eight field experiments, using different planting dates over 3 years. Five QTL, on four chromosomes, were detected for anthesis date. The four maturity QTL were on the same chromosomes as the anthesis QTL. Five QTL for grain filling were detected on all chromosomes. Three QTL, on chromosomes 1H and 2H, were detected for photoperiod sensitivity. Both parents contributed higher value alleles for all traits, except for photoperiod sensitivity. QTL epistasis was not significant. Two QTL explained most of the phenotypic variation for anthesis and physiological maturity. Non‐parental combinations of alleles at these loci account for the phenotypic transgressive segregation. Candidate genes for these QTL effects are eps2S (2H) and denso (3H). QTL for other traits had smaller effects and were coincident with genes and/or QTL for the same traits reported in other germplasm.
STIM, ORAI AND TRPC CHANNELS IN THE CONTROL OF CALCIUM ENTRY SIGNALS IN SMOOTH MUSCLE
Authors: Wang Youjun , Deng Xiaoxiang , Hewavitharana Thamara , Soboloff Jonathan , Gill Donald L
Published: August 2008

Ca2+ entry signals are crucial in the control of smooth muscle contraction. Smooth muscle cells are unusual in containing plasma membrane (PM) Ca2+ entry channels that respond to voltage changes, receptor activation and Ca2+ store depletion.

Activation of these channel subtypes is highly coordinated. The TRPC6 channel, widely expressed in most smooth muscle cell types, is largely non‐selective to cations and is activated by diacylglycerol arising from receptor‐induced phosholipase C activation.

Receptor activation results largely in Na+ ion movement through TRPC6 channels, depolarization and subsequent activation of voltage‐dependent L‐type Ca2+ channels. The TRPC6 channels also appear to be activated by mechanical stretch, resulting again in depolarization and L‐type Ca2+ channel activation. Such a coupling may be crucial in mediating the myogenic tone response in vascular smooth muscle.

The emptying of stores mediated by inositol 1,4,5‐trisphosphate receptors triggers the endoplasmic reticulum (ER) Ca2+ sensing protein stromal‐interacting molecule (STIM) 1 to translocate into defined ER–PM junctional areas in which coupling occurs to Orai proteins, which serve as highly Ca2+‐selective low‐conductance Ca2+ entry channels.

These ER‐PM junctional domains may serve as crucial sites of interaction and integration between the function of store‐operated, receptor‐operated and voltage‐operated Ca2+ channels. The STIM, Orai and TRPC channels represent highly promising new pharmacological targets through which such control may be induced.
Effect of initial shock wave voltage on shock wave lithotripsy‐induced lesion size during step‐wise voltage ramping
Authors: Connors Bret A. , Evan Andrew P. , Blomgren Philip M. , Handa Rajash K. , Willis Lynn R. , Gao Sujuan
Published: August 2008

OBJECTIVE

To determine if the starting voltage in a step‐wise ramping protocol for extracorporeal shock wave lithotripsy (SWL) alters the size of the renal lesion caused by the SWs.

MATERIALS AND METHODS

To address this question, one kidney from 19 juvenile pigs (aged 7–8 weeks) was treated in an unmodified Dornier HM‐3 lithotripter (Dornier Medical Systems, Kennesaw, GA, USA) with either 2000 SWs at 24 kV (standard clinical treatment, 120 SWs/min), 100 SWs at 18 kV followed by 2000 SWs at 24 kV or 100 SWs at 24 kV followed by 2000 SWs at 24 kV. The latter protocols included a 3–4 min interval, between the 100 SWs and the 2000 SWs, used to check the targeting of the focal zone. The kidneys were removed at the end of the experiment so that lesion size could be determined by sectioning the entire kidney and quantifying the amount of haemorrhage in each slice. The average parenchymal lesion for each pig was then determined and a group mean was calculated.

RESULTS

Kidneys that received the standard clinical treatment had a mean (sem) lesion size of 3.93 (1.29)% functional renal volume (FRV). The mean lesion size for the 18 kV ramping group was 0.09 (0.01)% FRV, while lesion size for the 24 kV ramping group was 0.51 (0.14)% FRV. The lesion size for both of these groups was significantly smaller than the lesion size in the standard clinical treatment group.

CONCLUSIONS

The data suggest that initial voltage in a voltage‐ramping protocol does not correlate with renal damage. While voltage ramping does reduce injury when compared with SWL with no voltage ramping, starting at low or high voltage produces lesions of the same approximate size. Our findings also suggest that the interval between the initial shocks and the clinical dose of SWs, in our one‐step ramping protocol, is important for protecting the kidney against injury.
Upper Estimates for a Moving Boundary Problem for Resonant Nonlinear Schrödinger Equations
Authors: Flavin J. N. , Rogers C.
Published: August 2008

Pointwise bounds are obtained for the solution of an initial boundary value problem for the resonant nonlinear Schrödinger equations. The context is that of a straight‐line region with prescribed moving boundaries, expanding or noncontracting, upon which zero (Dirichlet) conditions are imposed.
STRATEGIC INVESTMENT IN A NEW MIXED MARKET WITH LABOR‐MANAGED AND PROFIT‐MAXIMIZING FIRMS
Authors: Ohnishi Kazuhiro
Published: August 2008

This paper examines a continuous‐time mixed model of the strategic investment decisions of a labor‐managed income‐per‐worker‐maximizing firm and a profit‐maximizing firm in a new mixed market and constructs a set of perfect equilibria of the continuous‐time mixed model. The paper shows that there exists a particular equilibrium in which neither firm invests to its steady‐state reaction curve. The paper also finds that the existence of the particular equilibrium depends on each firm's being able to respond quickly to its rival's investment and that the particular equilibrium is profitable for each firm.
Clinical supervision: a means of promoting reciprocity between practitioners and academics
Authors: Pettifer Annie , Clouder Lynn
Published: August 2008

This paper explores the potential of adopting an alternative approach to the facilitation of clinical supervision in a practice context by focusing on the experiences of academic staff of facilitating clinical supervision for clinical colleagues. The exploratory study, which forms the basis for ideas generated, was very small and hence it might be better conceptualized as an analysis of conversations about practice understandings rather than research per se, and certainly, we make no claims of any possibility of generalizability. Nonetheless, we anticipate that our findings will be of interest to a wide audience involved in clinical supervision given that the supervision by academic staff of colleagues in practice is an unusual and unconventional departure from the norm.

The experiences of six academic staff from one higher education institution who were brought together to form a focus group provide the basis for discussion. Analysis of the structured discussion led to emergence of four major themes which are presented in an order that moves from the individuals’ experiences and perceptions of themselves in the process, to explore the relational nature of clinical supervision. The first theme highlights issues of professional identity or academics’ sense of themselves as health professionals and/or academics. This leads to the second theme that explores the tangible benefits identified by participants of providing clinical supervision as academics. The third theme about the perceived contribution that academics make to supervision, links, finally, to the perceived reciprocity that springs from clinical supervision relationships between academics providing supervision in practice, and clinicians. Our findings, based on this modest inquiry, suggest that this model of clinical supervision has potential to prove highly fruitful for both academic staff and their clinical colleagues.
Characterization of the Drosophila Gene‐Switch system in aging studies: a cautionary tale
Authors: Poirier Luc , Shane Amanda , Zheng Jie , Seroude Laurent
Published: August 2008

Genetic studies have shown that in many model organisms, single gene mutations can dramatically influence aging. Systems that allow researchers to control a gene's temporal and spatial expression pattern, known as inducible gene‐expression systems, are a valuable asset for the study of the influence of single genes on aging. One inducible gene‐expression system reported to allow temporal and tissue‐specific control of gene expression in Drosophila is the Gene‐Switch system. However, this system has not been extensively characterized in the context of aging research. This report uses six Gene‐Switch strains to examine the tissue localization and amount of expression achievable in the major tissue types of the fly. The quantitative analysis of adult flies fed with inducer through life reveals that the levels of expression are influenced by both the inducer concentration and the age of the animal in a strain‐specific manner. Furthermore, the relationship between inducer concentration and expression level is unique to each strain and, in some cases, to each gender. The analysis of the spatial expression patterns in several strains revealed expression in more tissue types than previously assumed. Finally, most Gene‐Switch strains display expression in the absence of inducer during development and/or during adulthood. These findings have important implications that may reconcile contradictions reported in studies investigating the effects of dFOXO on longevity. This study is an important guide to the design and interpretation of aging studies based on the Gene‐Switch system.
p16INK4a‐induced senescence is disabled by melanoma‐associated mutations
Authors: Haferkamp Sebastian , Becker Therese M. , Scurr Lyndee L. , Kefford Richard F. , Rizos Helen
Published: August 2008

The p16INK4a‐Rb tumour suppressor pathway is required for the initiation and maintenance of cellular senescence, a state of permanent growth arrest that acts as a natural barrier against cancer progression. Senescence can be overcome if the pathway is not fully engaged, and this may occur when p16INK4a is inactivated. p16INK4a is frequently altered in human cancer and germline mutations affecting p16INK4a have been linked to melanoma susceptibility. To characterize the functions of melanoma‐associated p16INK4a mutations, in terms of promoting proliferative arrest and initiating senescence, we utilized an inducible expression system in a melanoma cell model. We show that wild‐type p16INK4a promotes rapid cell cycle arrest that leads to a senescence programme characterized by the appearance of chromatin foci, activation of acidic β‐galactosidase activity, p53 independence and Rb dependence. Accumulation of wild‐type p16INK4a also promoted cell enlargement and extensive vacuolization independent of Rb status. In contrast, the highly penetrant p16INK4a variants, R24P and A36P failed to arrest cell proliferation and did not initiate senescence. We also show that overexpression of CDK4, or its homologue CDK6, but not the downstream kinase, CDK2, inhibited the ability of wild‐type p16INK4a to promote cell cycle arrest and senescence. Our data provide the first evidence that p16INK4a can initiate a CDK4/6‐dependent autonomous senescence programme that is disabled by inherited melanoma‐associated mutations.
The quantal theory of immunity and the interleukin‐2‐dependent negative feedback regulation of the immune response
Authors: Smith Kendall A. , Popmihajlov Zoran
Published: August 2008

Summary: The regulation of the tempo, magnitude, and duration of the immune response has been thought to reside solely with antigen for the past 50 years. However, with the discovery of the interleukins (ILs) 30 years ago, it became evident that these endogenous ‘lymphocytotrophic hormones’ provide the molecular mechanisms via classic hormone–receptor interactions. However, lacking in the hormonal regulatory capacity of the ILs were negative feedback mechanisms that functioned to switch off the positive driving force of the immune response, whether after antigen was cleared or when antigen persists, as with auto‐antigens, tumor antigens, persistent infections, or allografts. Our recent experimental data, reviewed herein, exploring the T‐cell antigen receptor (TCR) induction of the negative transcriptional regulator, forkhead box protein 3 (FOXP3), indicate that its expression is signaled by the T‐cell growth factor IL‐2. Once expressed, FOXP3 functions to restrict IL‐2 expression in reaction to continued TCR stimulation. Thus, IL‐2 regulates it own levels via a FOXP3‐mediated negative feedback loop. In contrast, we found no evidence that FOXP3+ cells actively suppress IL‐2 expression, thereby failing to support the notion that such cells regulate potential effector cells.
Congenital deformities and developmental abnormalities of the mandibular condyle in the temporomandibular joint
Authors: Kaneyama Keiseki , Segami Natsuki , Hatta Toshihisa
Published: August 2008

ABSTRACT  The temporomandibular joint (TMJ) consists of the mandibular condyle and the articular eminence of the temporal bone. The morphological development of the TMJ during prenatal life lags behind other joints in terms of both the timing of its appearance and its progress. At birth, the joint is still largely underdeveloped. There are many causes of the various growth disturbances and abnormalities of the mandibular condyle and related structures. Growth disturbances in the development of the mandibular condyle may occur in utero late in the first trimester and may result in disorders such as aplasia or hypoplasia of the mandibular condyle. Meanwhile, hyperplasia of the mandibular condyle is not visible at birth and seems to be gradually acquired during growth. In the present review article, the congenital abnormalities of the mandibular condyle are classified morphologically into three major groups and two subgroups from a clinical standpoint: (1) hypoplasia or aplasia of the mandibular condyle, including (i) primary condylar aplasia and hypoplasia, (ii) secondary condylar hypoplasia; (2) hyperplasia; and (3) bifidity. In addition, the molecular‐based etiology of anomalies of the mandibular condyle is also discussed.
Birth outcomes of cases with unclassified multiple congenital abnormalities and pregnancy complications in their mothers depending on the number of component defects. Population‐based case‐control study
Authors: Puhó Erzsébet H. , Czeizel Andrew E. , Ács Nándor , Bánhidy Ferenc
Published: August 2008

ABSTRACT  Multiple congenital abnormalities (MCA) represent the most severe category of structural birth defects, (i.e. congenital abnormalities [CA]). Unfortunately, most MCA are not recognized and/or identified as MCA syndromes or MCA associations in the clinical practice. The term unclassified MCA (UMCA) is used for this category of MCA. We decided to evaluate the component CA of UMCA cases. The population‐based large dataset of the Hungarian Case‐Control Surveillance of Congenital Abnormalities (1980–1996) was evaluated. ‘False’ MCA, such as complex CA, polytopic field defects and sequences were excluded from the category of MCA. In addition, MCA syndromes caused by chromosomal aberrations and major mutant genes with preconceptional origin were excluded from the dataset of the Surveillance. MCA syndromes caused by teratogens and MCA associations with well‐defined component CA were also excluded in the study. Thus, only UMCA cases (i) without the recognition of previously delineated MCA syndromes (ii) and/or without the identification of new MCA syndromes or (iii) caused by random combination of CA were included in the study. We compared data from 1349 cases with UMCA, 2405 matched population controls without any CA, and 21 494 malformed controls with isolated CA. There was a higher rate of stillbirth and a moderate male excess in UMCA cases, a somewhat shorter gestational age at delivery and an obvious reduction in birthweight. The intrauterine fetal growth retardation and rate of low‐birthweight newborns showed an association with the number of component CA in UMCA cases. A similar association was not found with gestational age and the rate of preterm birth. UMCA represent one of the most severe categories of CA. The degree of intrauterine fetal growth retardation depends on number of component CA in UMCA cases.
Rare case of fetal gastroschisis with aplasia of the foot and external genital organs
Authors: Rao Suresh Rangoji , Rao T. Ramesh , Gajula Somu Sekhar , Rao A.V.C.
Published: August 2008

ABSTRACT  Gastroschisis is a rare anomaly and is usually not associated with any other congenital anomalies. The embryology of gastroschisis and omphalocele remains a matter of speculation. Incidences of gastroschisis are particularly high among pregnancies in very young women. The present case is reported because of its rare association with the condition of gastroschisis, disrupted omphalocele, with aplasia of the foot and external genital organs, as well as imperforate anus with distal rectal atresia.
TNF, IFNG, IL6, IL10 and TGFB1 gene polymorphisms in South and Southeast Brazil
Authors: Visentainer Jeane Eliete Laguila , Sell Ana Maria , Da Silva Gisele Cristina , Cavichioli Ariza Danussa Gonçalves , Franceschi Danilo Santana Alessio , Lieber Sofia Rocha , De Souza Cármino Antonio
Published: August 2008

This study attempted to establish single nucleotide polymorphism frequencies of TNF, IL6, IFNG, IL10 and TGFB1 genes among healthy individuals from South and Southeast Brazil. The sample included 108 healthy individuals from South and 106 from Southeast Brazil. Polymerase chain reaction using sequence‐specific primers genotyping was performed for these gene cytokines with Cytokine Genotyping Primers (One Lambda, Canoga Park, CA, USA). Differences in genotypic and allelic frequencies between the populations were assessed by chi‐square with either Yates’ correction or Fisher's exact test. Our investigations showed that there were not any significant differences between these two Brazilian populations for these polymorphisms. A statistically significant difference in the distribution of alleles and genotypes for both IL6 and IL10 genes was observed between the Brazilian population and the African‐derived populations. IL6‐174GG genotype and allele G and IL10‐819CT/‐592CA genotypes are more frequent in African‐derived populations than in this mixed Brazilian population, while IL10‐1082GG genotype is more frequent in our population. This mixed Brazilian population is closer to those of Joinville's, Santa Catarina, and Rio de Janeiro's, Rio de Janeiro (RJ), Euro‐Brazilian populations than to those of Salvador's, Bahia, and Rio de Janeiro's, RJ, African‐Brazilian populations. These findings have an enormous importance for experimental design and empowering future linkage and association mapping studies of the role of cytokines in human diseases and allotransplantation outcome in Brazil.
Localization and Dynamic Change of Saikosaponin in Root of Bupleurum chinense
Authors: Tan Ling‐Ling , Cai Xia , Hu Zheng‐Hai , Ni Xi‐Lu
Published: August 2008

Anatomical, histochemical and phytochemical methods were used to investigate the structure, the localization and content changes of total saikosaponin and saikosaponin‐a of the roots of Bupleurum chinense DC. at different developmental stages. Results showed that saikosaponin was mainly distributed in pericycle and primary phloem in the young root; but in the mature root, it was mainly distributed in vascular cambium and secondary phloem. During the whole growth period from the pre‐blossom, blossom, fruit, and fruit mature periods until the pre‐withering period, it was in the fruit mature period that both the total saikosaponin content and the saikosaponin‐a content reached the highest level. So the last 20 d of October was considered as the right collecting season for the drug of B. chinense. In addition, the quality of 1‐year‐old drug was better than that of 2‐year‐old drug due to its higher saikosaponin content. On the other hand, judging from the external characteristics of the drug, the one with an acerose taproot and more lateral roots was of better quality. The results offered theoretical bases for selecting medicinal material of high quality and determining the most appropriate harvesting stage and part of B. chinense.
Nicotine Concentration in Leaves of Flue‐cured Tobacco Plants as Affected by Removal of the Shoot Apex and Lateral Buds
Authors: Wang Shu‐Sheng , Shi Qiu‐Mei , Li Wen‐Qing , Niu Jun‐Fang , Li Chun‐Jian , Zhang Fu‐Suo
Published: August 2008

It is believed that the nicotine concentration in tobacco is closely correlated with the amount of nitrogen (N) supplied. On the other hand, N uptake mainly occurs at the early growth stage, whereas nicotine concentration increases at the late growth stage, especially after removing the shoot apex. To identify the causes of the increased nicotine concentration in tobacco plants, and to compare the effects of different ways of mechanical wounding on nicotine concentration, field experiments were carried out in Fuzhou, Fujian Province in 2003 and 2004. Excision of the shoot apex had almost no influence on N content in the plant; however, it caused dramatic increases in nicotine concentration in leaves, especially in the middle and upper leaves. An additional increase of the nicotine concentration was obtained by removal of axillary buds. The wounding caused by routine leaf harvests, however, did not change the leaf nicotine concentration, and neither did reducing leaf harvest times. The present results revealed no direct relationship between N supply and nicotine concentration in tobacco leaves, and indicate that not all kinds of mechanical wounding were capable of stimulating nicotine synthesis in tobacco plants. Since nicotine production is highly dependent on the removal of apical meristems and hence on the major sources of auxin in the plant, and application of 1‐naphthylacetic acid onto the cut surface of the stem after removing the shoot apex markedly decreased the nicotine concentration in different leaves and the total nicotine content in the plant, the results suggest that decreased auxin supply caused by removal of the shoot apex as a kind of mechanical wounding might regulate nicotine synthesis in the roots of tobacco plants.
Monoclonal Antibody‐Based Enzyme Linked Immunosorbent Assay for the Analysis of Jasmonates in Plants
Authors: Deng Aixing , Tan Weiming , He Suping , Liu Wei , Nan Tiegui , Li Zhaohu , Wang Baomin , Li Qing X.
Published: August 2008

Methyl jasmonate (MeJA) and its free‐acid form, jasmonic acid (JA) are naturally occurring plant growth regulators widely distributed in higher plants. In order to improve the sensitivity for the analysis of MeJA at low levels in small amounts of plant samples, a monoclonal antibody (MAb) (designated as MAb 3E5D7C4B6) against MeJA was derived from a JA‐bovine serum albumin (BSA) conjugate as an immunogen. The antibody belongs to the IgG1 subclass with a κ type light chain and has a dissociation constant of approximately 6.07 × 10−9 M. MAb3E5D7C4B6 is very specific to MeJA. It was used to develop a direct competitive enzyme‐linked immunosorbent assay (dcELISA), conventional and simplified indirect competitive ELISAs (icELISA). JA was derivatized into MeJA for the ELISA analysis. The IC50 value and detection range for MeJA were, respectively, 34 and 4–257 ng/mL by the conventional icELISA, 21 and 3–226 ng/mL by the simplified icELISA and 5.0 and 0.7–97.0 ng/mL by the dcELISA. The dcELISA was more sensitive than either the conventional or simplified icELISA. The assays were used to measure the content of jasmonates as MeJA in tobacco leaves under drought stress or inoculated with tobacco mosaic virus and tomato leaves inoculated with tomato mosaic virus or Lirioinyza sativae Blanchard as compared with the corresponding healthy leaves. The increased jasmonates content indicated its role in response to the drought stress and pathogens.
Host preference of the bean weevil Zabrotes subfasciatus
Authors: Teixeira Isabel Ribeiro do Valle , Barchuk Angel Roberto , Zucoloto Fernando Sérgio
Published: August 2008

It is largely known that the range of an insect diet is mostly determined by oviposition behavior, mainly in species with endophytic larvae such as Zabrotes subfasciatus. However, the proximate factors determining host choice and the subsequent steps leading to the expansion or reduction of the host number and occasional host shifts are largely unknown. We analyzed various factors determining host preference of Z. subfasciatus through the evaluation of: (i) oviposition preference of a wild population of Z. subfasciatus on the usual host (bean) and unusual hosts (lentil, chickpea and soy), and the performance of the offspring; (ii) artificial selection for increasing preference for hosts initially less frequently chosen; (iii) comparison of oviposition behavior between two different populations (reared for ∼30 generations in beans or chickpeas, respectively); (iv) oviposition timing on usual and unusual hosts; and (v) identification of preference hierarchies. We found that when using unusual hosts, there is no correlation between performance and preference and that the preference hierarchy changes only slightly when the population passes through several generations on the less frequently accepted host. We also found a positive response to artificial selection for increasing oviposition on the less preferred host; however, when the host‐choice experiment involved two varieties of the usual host, the response was faster than when the choice involved usual and unusual hosts. Finally, beetles reared on an unusual host (chickpea) for 26 generations showed similar good fitness on both usual and unusual hosts, indicating that the use of a new host does not necessarily result in the loss of performance on the original host. Nevertheless, this population showed lower fitness on the usual host than that of the original population, suggesting an underlying partial trade‐off phenomenon which may contribute to a broadening of diet of this insect species.
Effect of temperature on the demography of Galerucella birmanica (Coleoptera: Chrysomelidae)
Authors: Zheng Fu‐Shan , Du Yu‐Zhou , Wang Zhi‐Jie , Xu Jia‐Jun
Published: August 2008

Studies on the effect of temperature on the development of the water chestnut beetle, Galerucella birmanica Jacoby were carried out in the laboratory at seven different temperatures: 16 °C, 19 °C, 22 °C, 25 °C, 28 °C, 31 °C and 34 °C. The developmental time decreased with increase in temperature. The developmental time at 16 °C, 19 °C, 22 °C, 25 °C, 28 °C, 31 °C and 34 °C was 96.60, 80.68, 58.96, 43.48, 35.03, 30.08 and 28.02 days for the period from egg hatching to adult emergence, respectively. The developmental threshold estimated for a generation by linear regression was 10.36 °C. The fecundity per female at 22 °C, 25 °C, 28 °C, 31 °C and 34 °C was 102.3, 134.5, 141.2, 130.1 and 116.2 eggs, respectively. Oviposition period ranged from 15.6 days at 22 °C to 8.6 days at 34 °C. Hatchability of eggs was highest at 31 °C with 76.9% and lowest at 34 °C with 57.1%. The highest generation survival rate was 65.3% at 31 °C, and the intrinsic rate of natural increase (rm) for G. birmanica was the highest at 34 °C.
SENSORY QUALITY PERFORMANCE OF TWO NECTARINE FLESH TYPOLOGIES EXPOSED TO DISTANT MARKET CONDITIONS
Authors: INFANTE RODRIGO , MENESES CLAUDIO , PREDIERI STEFANO
Published: August 2008

The objective of this research was to evaluate the shelf life of two nectarine flesh typologies in order to determine the exporting potential of fresh nectarines to distant markets. “Maria Dolce” (subacid fruit type) and “Venus” (normal fruit type) nectarines were harvested at two maturity stages, based on fruit ground color. Fruits were stored at 0C and 90% R.H. for 14 or 42 days, simulating storage duration aimed respectively to shipping to close or distant marketplaces. Nectarines were evaluated after a period of ripening at 20C, when flesh firmness reached 9.8–19.6 N. Visual appearance, color, aroma, flesh texture, sweetness, sourness, juiciness, flavor and acceptability were evaluated. Both varieties presented a better eating quality when harvest was delayed. “Maria Dolce” presented high storage ability, reaching even at 42 days the same acceptability of fruit not subjected to cold storage. “Venus” showed a significant decrease in acceptability, indicating a not sufficient tolerance to long storage.

PRACTICAL APPLICATIONS

The poor eating quality of fresh nectarines destined to distant markets is one of the main problems that are facing some countries as Chile, which is a conspicuous exporter of off‐season stone fruits to the Northern Hemisphere and Latin America. This research is focused on the comparison of quality of a normal fruit type nectarine, which is one of the most cultivated in Chile, and of a subacid nectarine; experimental design simulated two exportation regimes for close or distant marketplaces. Subacid types have been recently available in the world variety assortment system and the sensorial quality performance has yet not been tested after long postharvest storage.
The Birth of the CAP Die Geburt der GAP La naissance de la PAC
Authors: Stead David R.
Published: August 2008

The Birth of the CAP

Fifty years ago, a Conference was held at Stresa which could be said to be the single event that most appropriately marks the birth of the CAP. Although five policy objectives had been written into the 1957 Treaty of Rome, these have been widely criticised for being vague and contradictory, and the Treaty contained very few stipulations on the specific policy instruments to be adopted. The Stresa Conference made important, but incomplete, progress towards finalising the policy framework. Most notably, it was generally agreed to avoid a level of price support that created unwanted commodity surpluses and inhibited structural adjustment. But these good intentions, and the positive ‘European spirit’ of the Conference, began to unravel as soon as the fraught decisions were taken on the details of unifying the protectionist agricultural policies of six different countries. In particular, the decision to fix the initial level of common cereals prices at the upper end of the national spread set an unsatisfactory reference point for other support prices; and an attempt to introduce a genuine common structural policy was rejected. At the turn of the 1970s, the CAP was clearly unbalanced and protectionist, but the Community’s first fully‐fledged common policy had been constructed.