bluuebunny/crossref_metadata_2025 huggingface dataset:
Biodiversity and the biogeographic relationships of the Amphipoda: Gammaridea on the French coastline
Authors: Dauvin Jean-Claude , Bellan-Santini Denise
Published: May 2004

A recent inventory of the benthic Gammaridea: Amphipoda species on the French continental coastline catalogued 495 species. An analysis of the biodiversity and the biogeographic relationships that exist between the French Amphipoda: Gammaridea, living on the coastline that extends along 10° latitude range in the temperate region between 41° and 51° North and the other gammaridean faunas living in the north-eastern Atlantic has drawn the pattern of diversity in this marine invertebrate group on a large biogeographical scale. Gammaridean amphipods exhibit a latitudinal gradient over the total number of species, including the continental shelf species and the bathyal species. There are four main fauna groups, which correspond to the biogeographical zones of the north-eastern Atlantic: (1) a cold arctic and cool-temperate Svalbard and Norwegian coastal fauna; (2) a cool-temperate boreal and Boreal–Lusitanian United Kingdom, Irish and English Channel shallow fauna; (3) a warm-temperate Lusitanian Bay of Biscay and subtropical central Atlantic fauna; and (4) a subtropical Mediterranean fauna. The French fauna appears particularly rich, presenting 44% of the 1119 species recorded in the north-eastern Atlantic along the 50° latitude range (30°N–80°N).  

This is obviously due to France's intermediate latitudinal location within the Lusitanian temperate biogeographical zone, which produces a biogeographical cross between the boreal fauna in the north and the warm temperate and sub-tropical fauna in the south.
The localization of LAP2β in bovine oocytes after in vitro activation and fertilization
Authors: Isaji Mamiko , Iwata Hisataka , Harayama Hiroshi , Miyake Masashi
Published: May 2004

The present study was designed to clarify the localization of LAP2β and to compare it with those of lamins A/C and B in bovine oocytes after activation and in vitro fertilization (IVF). After fertilization, LAP2β was not found until telophase II, and was observed around condensed chromatin after the extrusion of the second polar body, but not in activated oocytes. Although the reaction of LAP2β was temporally negative or weak on the membrane of the growing small pronuclei, it became strong on the fully grown pronuclei of both activated and fertilized oocytes. Examination of the timing of DNA synthesis using bromodeoxyuridine revealed that the expression of LAP2β on the pronuclear membrane became strong around the end of the DNA synthesis in both activated and fertilized oocytes. Both male and female pronuclei exhibited the same reactivity to all nuclear proteins examined. It was also shown that LAP2β first assembled around condensed chromatin, followed by the integration of lamins B and A/C as in somatic cells. LAP2β staining was maintained on the nuclear membrane of the embryonic cells at interphase until the later stage of preimplantational development. There were no differences between parthenogenetic and fertilized embryos in the expression and localization of LAP2β from the PN-stage oocyte to the blastocyst. The assembly of LAP2β was observed around the telophase chromatin of both blastocyst and cumulus cells. Thus, it was shown that the timing of the aggregation of LAP2β at the second meiosis was different from that in the mitosis of blastocyst and somatic cells. LAP2β was constantly expressed in the nuclear membrane in in vitro fertilized and parthenogenetic embryos as was lamin B, and lamin A/C was expressed stage-dependently in both types of embryos. Lamin A/C was positive in some inner cell mass cells of parthenogenetic blastocysts, but not those of in vitro fertilized embryos.
The role of calcium in the nuclear maturation of Bufo arenarum oocytes
Authors: Zelarayán Liliana I. , Toranzo Graciela Sánchez , Oterino Julia M. , Bühler Marta I.
Published: May 2004

In Bufo arenarum, progesterone is the physiological maturation inducer. However, in this species, oocytes reinitiate meiosis with no need of an exogenous hormonal stimulus when deprived of their enveloping cell, a phenomenon called spontaneous maturation. We demonstrated that in Bufo arenarum spontaneous maturation occurs only in oocytes obtained during the reproductive period, which can be considered competent to mature spontaneously, in contrast to those in the non-reproductive period, which are incompetent. Interestingly, full-grown Bufo arenarum oocytes always respond to progesterone regardless of the season in which they are obtained. There is a general consensus that both a transient increase in intracellular calcium and a decrease in cAMP-dependent protein kinase activity are the first steps in the mechanisms by which progesterone induces maturation in amphibians. In the present work we analysed the role of calcium in the spontaneous and progesterone-induced maturation of Bufo arenarum oocytes. Results demonstrated that the absence of calcium in the incubation medium or the prevention of Ca2+ influx by channel blockers such as CdCl2 or NiCl2 did not prevent meiosis reinitiation in either type of maturation. The inhibition of the Ca2+-calmodulin complex in no case affected the maturation of the treated oocytes. However, when the oocytes were deprived of calcium by incubation in Ca2+-free AR + A23187, meiosis resumption was inhibited. In brief, we demonstrated that in Bufo arenarum the reinitiation of meiosis is a process independent of extracellular calcium at any period of the year and that oocytes require adequate levels of intracellular calcium for germinal vesicle breakdown to occur.
Overheating is detrimental to meiotic spindles within in vitro matured human oocytes
Authors: Sun Xiao-Fang , Wang Wei-Hua , Keefe David L.
Published: May 2004

The present study was designed to examine the effects of overheating on meiotic spindle morphology within in vitro matured human oocytes using a polarized light microscope (Polscope). Immature human oocytes at either germinal vesicle or metaphase I stage were cultured in vitro for 24–36 h until they reached metaphase II (M-II) stage. After maturation, oocytes at M-II stage were imaged in the living state with the Polscope at 37, 38, 39 and 40 °C for up to 20 min. After heating, oocytes were returned to 37 °C and then imaged for another 20 min at 37 °C. The microtubules in the spindles were quantified by their maximum retardance, which represents the amount of microtubules. Spindles were intact at 37 °C during 40 min of examination and their maximum retardance (1.72–1.79) did not change significantly during imaging. More microtubules were formed in the spindles heated to 38 °C and the maximum retardance was increased from 1.77 before heating to 1.95 at 20 min after heating. By contrast, spindles started to disassemble when the temperature was increased to 39 °C for 10 min (maximum retardance was reduced from 1.76 to 1.65) or 40 °C for 1 min (maximum retardance was reduced from 1.75 to 1.5). At the end of heating (20 min), fewer microtubules were present in the spindles and the maximum retardance was reduced to 0.8 and 0.78 in the oocytes heated to 39 °C and 40 °C, respectively. Heating to 40 °C also induced spindles to relocate in the cytoplasm in some oocytes. After the temperature was returned to 37 °C, microtubules were repolymerized to form spindles, but the spindles were not reconstituted completely compared with the spindles imaged before heating. These results indicate that spindles in human eggs are sensitive to high temperature. Moreover, maintenance of an in vitro manipulation temperature of 37 °C is crucial for normal spindle morphology.
Effects of oocyte age, cumulus cells and injection methods on in vitro development of intracytoplasmic sperm injection rabbit embryos
Authors: Zheng Yue-Liang , Jiang Man-Xi , Zhang Yan-Ling , Sun Qing-Yuan , Chen Da-Yuan
Published: May 2004

This study assessed the effects of oocyte age, cumulus cells and injection methods on in vitro development of intracytoplasmic sperm injection (ICSI) rabbit embryos. Oocytes were recovered from female rabbits superovulated with PMSG and hCG, and epididymal sperm were collected from a fertile male rabbit. The oocyte was positioned with the first polar body at 12 o'clock position, and a microinjection needle containing a sperm was inserted into the oocyte at 3 o'clock. Oolemma breakage was achieved by aspirating ooplasm, and the aspirated ooplasm and sperm were re-injected into the oocyte. The injected oocytes were cultured in M199 medium containing 10% fetal calf serum at 38 °C with 5% CO2 in air. The results showed that oocytes injected at 1 h post-collection produced a higher (p<0.05) fertilization rate than those injected at 4 or 7 h post-collection. Blastocyst rate in the 1 h group was higher (p<0.05) than in the 7 h group. Denuded oocytes (group A) and oocytes with cumulus cells (group B) were injected, respectively. Rates of fertilization and development of ICSI embryos were not significantly different (p<0.05) between the two groups. Four ICSI methods were applied in this experiment. In methods 1 and 2, the needle tip was pushed across half the diameter of the oocyte, and oolemma breakage was achieved by either a single aspiration (method 1) or repeated aspiration and expulsion (method 2) of ooplasm. In methods 3 and 4, the needle tip was pushed to the oocyte periphery opposite the puncture site, and oolemma breakage was achieved by either a single aspiration (method 3) or repeated aspiration and expulsion (method 4) of ooplasm. Fertilization rate in method 2 was significantly higher (p<0.05) than in methods 1 and 3. Blastocyst rates were not significantly different (p<0.05) among methods 1, 3 and 4, but method 2 produced a higher (p<0.05) blastocyst rate than method 3.
Isolation and culture of pluripotent cells from in vitro produced porcine embryos
Authors: Li Ming , Li Yong-Hai , Hou Yi , Sun Xiao-Fang , Sun Qingyuan , Wang Wei-Hua
Published: May 2004

The present study was designed to examine whether in vitro produced porcine embryos can be used to establish an embryonic stem (ES) cell line. Porcine embryos were produced by in vitro maturation and in vitro fertilization. Embryos at the 4-cell to blastocyst stages were cultured in an ES medium containing 16% fetal bovine serum with mouse embryonic fibroblasts as a feeder layer. It was found that ES-like colonies were derived only from blastocysts. When these ES-like colonies were separated in 0.25% trypsin–0.02% EDTA solution and cultured again, ES-like colonies were further observed in the subsequent culture until the fourth passage. The cells from ES-like colonies showed positive alkaline phosphatase activity. Some cells from the colonies differentiated into several types of cells in vitro when they were cultured in the medium without feeder layers and leukemin inhibitory factor. Embryoid bodies were also formed when the cells were cultured in a suspension status. These results indicate that porcine ES-like cells can be derived from in vitro produced porcine blastocysts and these ES-like cells are pluripotent. The culture system used in the present study is useful to isolate and culture ES cells from in vitro produced porcine embryos.
Prevalence of stimulant use for attentional dysfunction in children with phenylketonuria
Authors: Arnold G. L. , Vladutiu C. J. , Orlowski C. C. , Blakely E. M. , DeLuca J.
Published: May 2004

Sumary: Recent data suggest that children with phenylketonuria (PKU) and poor metabolic control may have an increased prevalence of attentional dysfunction. However, few formal studies have addressed this topic in detail. We reviewed the medical records of 38 school‐aged children with early and continuously treated PKU to determine the prevalence of stimulant use for attentional dysfunction, and to determine the relationship between metabolic control and attentional symptoms. Twenty‐six per cent of the PKU children used a stimulant medication for attentional dysfunction. This is significantly higher than in an age‐ and sex‐matched control group consisting of children with type I diabetes mellitus (6.5%,p<0.006), and also considerably higher than population norms for attention deficit hyperactivity disorder (ADHD) (5%). We also found a significant relationship between phenylalanine levels and stimulant use or attentional symptoms. Mean plasma phenylalanine concentration was 486 µmol/L in the non‐stimulant‐using group and 792 µmol/L in the stimulant‐using group (p<0.02). Mean phenylalanine concentration was 462 µmol/L in the group not reporting attentional symptoms, and was 702 µmol/L in the symptomatic group (p<0.05). Parents of the stimulant‐using children felt that the stimulants were efficacious in treating their child's attentional symptoms. Stimulant use and parent reports of attentional dysfunction are quite common in our PKU patients and appear to be strongly related to higher phenylalanine concentrations.
Living‐donor liver transplantation for propionic acidaemia
Authors: Yorifuji T. , Kawai M. , Mamada M. , Kurokawa K. , Egawa H. , Shigematsu Y. , Kohno Y. , Tanaka K. , Nakahata T.
Published: May 2004

Summary: Three patients with the severe form of propionic acidaemia were treated with living‐donor liver transplantation (LDLT). The procedure was successful for all patients and the incidence of metabolic decompensation was reduced dramatically even without protein restriction. Biochemically, however, the improvement was not significant and the patients continued to excrete large amounts of propionic acid metabolites. One of the patients experienced a severe acidaemic episode 3 years after transplantation. LDLT has a beneficial effect on the care of severely affected patients since it reduces the risk of metabolic decompensation and improves the quality of life with less strict dietary control. Adequate protein restriction and medication need to be maintained even after successful transplantation.
Executive function impairment in early‐treated PKU subjects with normal mental development
Authors: Leuzzi V. , Pansini M. , Sechi E. , Chiarotti F. , Carducci Cl. , Levi G. , Antonozzi I.
Published: May 2004

Summary: Executive functions were studied in 14 early and continuously treated PKU subjects (age 10.8 years, range 8–13) in comparison with controls matched for IQ, sex, age and socioeconomic status. Brain MRI examination was normal in all PKU patients. Neuropsychological evaluation included Wisconsin Card Sorting Test, Rey‐Osterreith Complex Figure Test, Elithorn's Perceptual Maze Test, Weigl's Sorting Test, Tower of London, Visual Search and Motor Motor Learning Test. Whatever the IQ, PKU subjects performed worse than controls in tests exploring executive functions. Subgrouping the PKU subjects according to the quality of dietary control for the entire follow‐up period (using 400 µmol/L as cut‐off value for blood phenylalanine (Phe) concentration) showed that patients with worse dietary control performed more poorly than both the PKU group with the best dietary control and the control group. However, a mild impairment of executive functions was still found in PKU patients with a good dietary control (Phe<400 µmol/L) compared to controls. Concerning the PKU group as a whole, no linear correlation was found between neuropsychological performance and historical and concurrent biochemical parameters. We conclude that (a) PKU patients, even when treated early, rigorously and continuously, show an impairment of frontal lobe functions; (b) a protracted exposure to moderately high levels of Phe can affect frontal lobe functions independently of the possible effect of the same exposure on IQ; (c) in order to reduce the risk of frontal lobe dysfunction, the target of dietary therapy should be to maintain blood Phe concentration below 400 µmol/L.
Carrier screening for Canavan disease in Australia
Authors: Howell V. M. , Proos A. L. , LaRue D. , Jensen C. H. , Beach F. , Burnett L.
Published: May 2004

Summary: This study reports, for the first time, the carrier frequency of Canavan disease in the Ashkenazi Jewish population in Australia, and the identification of a novel mutation in the ASPA gene.
A Japanese case with inosine triphosphate pyrophosphohydrolase deficiency attributable to an enzymatic defect in white blood cells
Authors: Sumi S. , Ueta A. , Maeda T. , Ito T. , Ohkubo Y. , Togari H.
Published: May 2004

Summary: Inosine triphosphate pyrophosphohydrolase (ITPase) deficiency is characterized by abnormal accumulation of inosine triphosphate. We describe the first Japanese case with ITPase deficiency and demonstrate that the deficiency of ITPase activity is not only found in erythrocytes but also in white blood cells.
Acute metabolic crisis with extreme deficiency of glutathione in combination with decreased CSF levels of leukotriene C4 in a patient with glutathione synthetase deficiency
Authors: Mayatepek E. , Meissner T. , Gröbe H.
Published: May 2004

Summary: A 32‐year‐old man with glutathione synthetase deficiency developing an acute metabolic crisis is described. During this acute episode, intracellular glutathione content in erythrocytes was below the detection limit (<0.3 mmol/L). Leukotriene C4 in CSF and urinary leukotriene E4 were massively decreased, indicating an impaired synthesis of cysteinyl leukotrienes. Clinical recovery after one week was accompanied by a clear improvement of these biochemical parameters. The highly disturbed glutathione synthesis is postulated to be the reason for a deficient synthesis of cysteinyl leukotrienes, which may at least in part be responsible for the severe clinical symptoms.
Häufigkeit psychischer Auffälligkeiten und Begleitsymptome bei drei- bis sechsjährigen Kindern: Ergebnisse der Braunschweiger Kindergartenstudie
Authors: Kuschel A. , Lübke A. , Köppe E. , Miller Y. , Hahlweg K. , Sanders M. R.
Published: May 2004

Zusammenfassung: Fragestellung: Im Rahmen der Braunschweiger Kindergartenstudie wurde die Häufigkeit psychischer Auffälligkeiten und Begleitsymptome bei Kindern im Alter zwischen 3 und 6 Jahren untersucht. Methode: Die Untersuchung wurde im November 1998 in allen städtischen Kindertagesstätten Braunschweigs mit einer leicht modifizierten Version des Elternfragebogens über das Verhalten von Kindern und Jugendlichen/CBCL 4-18 durchgeführt. Von N = 809 Kindern liegen Elterneinschätzungen vor. Ergebnisse: Die Prävalenzraten für psychische Störungen bei Kindergartenkindern liegen zwischen 0,5% und 5,0%, wobei in dieser Altersgruppe Aggressives Verhalten, Aufmerksamkeitsprobleme und Soziale Probleme am häufigsten auftreten. Es werden außerdem Komorbiditätsraten für die einzelnen Syndromskalenpaare der CBCL berichtet. Diskussion: Abschließend werden die vorliegenden Ergebnisse mit anderen Untersuchungen verglichen und Implikationen vor allem für die Prävention kindlicher Verhaltensauffälligkeiten diskutiert.
Geometrical optics phase matching of radio occultation signals
Authors: Jensen Arne Skov , Lohmann Martin S. , Nielsen Alan Steen , Benzon Hans‐Henrik
Published: May 2004

Remote measurements of the atmospheric state can be performed by radio occultation between satellites, a GPS satellite transmitting a radio signal to a receiving low Earth orbit (LEO) satellite, or between LEO satellites. The bending angle of the traversing optical ray can be measured by detecting the Doppler shift of radio signals. The bending angle is an integrated measure of the refractive index in the atmosphere traversed by the optical ray. With a time series (profile) of the bending angle, it is possible to perform an inversion to obtain the refractive index. Various techniques for the retrieval of the bending profile already exist. The most recent methods have solved the problem of multipath, i.e., when the atmosphere allows several rays to exist simultaneously. The paper presents a new method for the reconstruction of bending angle as a single‐valued function of impact parameter from complex radio occultation signal under multipath propagation conditions. The method utilizes the assumption of spherical symmetry of refractivity, i.e., n() = n(r), and the principle of synthetic aperture, thus allowing sub‐Fresnel resolution. A distinctive feature of the method, as compared to previously known methods, is direct applicability for arbitrary orbits of transmitting and receiving satellites, without intermediate propagation of complex electromagnetic field to circle or straight line. This comes at the expense of impossibility to reduce the method to a FFT. The method can be useful for inverting radio occultation signals and for validation of other radio holographic methods.
Why have some countries on international rivers been successful negotiating treaties? A global perspective
Authors: Song Jennifer , Whittington Dale
Published: May 2004

This paper presents a typology of international rivers based on asymmetries in economic and political power among riparian states. This typology is then used, along with other factors such as the spatial location of riparians on the river, to explore the question of why some riparians on international rivers have been able to successfully negotiate treaties and others have not. The findings lend support to both economic and political economy explanations of cooperative action on international rivers. International rivers with riparians with countervailing economic and political power are far more likely to have negotiated treaties than other river types. Riparian states on international rivers sharing a “western civilization” were much more likely to have concluded treaties than riparian states on rivers in other civilizations. Somewhat surprisingly, rivers that cross “civilization boundaries” appear no less likely to have treaties than international rivers than run entirely through riparian states that share a single civilization. Adjacent upstream/downstream or “side‐by‐side” riparians were less likely to have concluded treaties than “country pairs” with other spatial relationships.
Evaluation of tropical cirrus cloud properties derived from ECMWF model output and ground based measurements over Nauru Island
Authors: Comstock Jennifer M. , Jakob Christian
Published: May 2004

Cirrus clouds play an important role both radiatively and dynamically in the tropics. Understanding the mechanisms responsible for the formation and persistence of tropical cirrus is an important step in accurately predicting cirrus in forecast and climate models. In this study, we compare ground‐based measurements of cloud properties with those predicted by the ECMWF model at a location in the tropical western Pacific. Our comparisons of cloud height and optical depth over an 8 month time period indicate that the model and measurements agree well. The ECMWF model predicts cirrus anvils associated with deep convection during convectively active periods, and also isolated cirrus events that are influenced by large‐scale vertical ascent. We also show through examination of an upper tropospheric cirrus case that the model produces tropospheric waves that appear to influence the morphology and maintenance of the cirrus layer.
Validation of the self‐consistency of GOMOS NO3, NO2 and O3 data using chemical data assimilation
Authors: Marchand Marion , Bekki Slimane , Hauchecorne Alain , Bertaux Jean‐Loup
Published: May 2004

The NO3 measurement by the GOMOS instrument on board the ENVISAT platform is the first satellite measurements of this species. The simultaneous measurements of O3 and NO2, which are strongly coupled chemically to NO3, allow us to test the self‐consistency of the GOMOS measurements of the different species. In this paper, the self‐consistency of the nighttime measurements by GOMOS of O3, NO2 and NO3 are tested using chemical data assimilation. Measurements obtained between 25 and 55 km during two distinct periods are assimilated. Analyzed NO3 (i.e., NO3 calculated by the model after assimilation of GOMOS O3 and NO2 data) are then compared to corresponding GOMOS NO3 measurements in correlation plots (GOMOS NO3 versus analyzed NO3). Overall, the differences between the NO3 measurements and corresponding analyzed NO3 are found to be small, about 10% on average. The linear regressions for both periods are also found to be close to the 1‐to‐1 line with small standard errors. This agreement indicates that O3, NO2 and NO3 GOMOS measurements are self consistent chemically and that there is no substantial bias in GOMOS NO3 data. It also suggests that the nighttime NO3 chemistry is well understood.
The Right Tool for the Job? Modeling, Spatial Relationships, and Styles of Scientific Practice in the UK Foot and Mouth Crisis
Authors: Bickerstaff Karen , Simmons Peter
Published: May 2004

In this paper we explore the expert controversy over the management of a major rural risk issue, the foot and mouth disease (FMD) outbreak that affected the United Kingdom in 2001, and in particular the role of predictive epidemiological modeling in the decisionmaking process. We pose the questions of why this technique was identified as the right tool for the job by government and why, at the same time, its use was so fiercely contested by other experts in animal health. To set our analysis in context we outline briefly the causes, characteristics, and consequences of FMD together with its history in the United Kingdom. We then provide an account of the 2001 FMD outbreak and the policies that were employed to control the epidemic. In the main discussion we integrate the geographical concept of spatial practices with the concept, drawn from the sociology of scientific knowledge, of styles of scientific practice and apply this to the analysis of the knowledge practices and arguments of the scientific groups that advised on controlling the epidemic. We analyse the key differences between expert groups and their policy recommendations in terms of their different styles of scientific spatial practice. In the rhetorical boundary work of the opposing scientific groups we see these differences in ‘style’ being invoked to delineate the boundaries of ‘sound science’ and thereby legitimate their respective policy prescriptions. We conclude by discussing the relationship between styles of scientific spatial practice and recent trends in government policy style and its implications for future risk policy.
The Leeuwin Current, eddies and sub-Antarctic waters off south-western Australia
Authors: Cresswell G. R. , Griffin D. A.
Published: May 2004

Data from a research vessel cruise in late 1994 and several years of satellite observations revealed complex interactions of ocean features off south-western Australia. The ship measurements showed that the Leeuwin Current (LC) commonly ran at 0.5 m s–1 above the upper continental slope and extended down to approximately 250 m. South of the continent, a 200-km diameter anticyclonic eddy depressed the ocean structure in the upper 1000 m. The eddy showed influences of the LC, deep mixing in winter and summer heating. The sub-Antarctic water around the eddy was cooler, fresher and richer in nutrients and oxygen than both the eddy and the LC. Satellite thermal and topographic measurements showed that cyclonic eddies accelerated the LC along the southern upper continental slope, whereas anticyclonic eddies diverted it out to sea and then back again. The images suggested that weak eddies originating east of the Great Australian Bight migrate westward, first encountering the continental slope off the Recherche Archipelago. There, the anticyclonic eddies take on warm water from the LC and strengthen. Several anticyclonic eddies were followed westward beyond the archipelago for 18 months as they drifted at up to 5 km day–1 and interacted with the LC and with one another.
Expression of neuropeptide Y is increased in murine endometrial epithelium during the peri-implantation period under regulation by sex steroids
Authors: Yonaha Hitoshi , Minoura Hiroyuki , Yoshida Toshimichi , Takeuchi Shigeto , Noda Naomi , Tanaka Keisuke , Nishiura Rika , Kawato Hiroaki , Toyoda Nagayasu
Published: May 2004

Oligopeptide hormones are involved in cell–cell interaction during embryonal implantation and neuropeptide Y (NPY) is expressed in the human placenta and decidual cells in the third trimester of pregnancy. However, there is no report regarding the intrauterine localisation and the functions of NPY during the peri-implantation period. In the present study, the spatiotemporal changes in NPY expression in the murine uterus during the peri-implantation period were investigated using reverse transcription–polymerase chain reaction (RT-PCR), quantitative RT-PCR and immunohistochemical techniques, as were the effects of sex steroids on NPY mRNA expression in primary cultured murine uterine epithelial cells. Neuropeptide Y mRNA was increased in the pregnant murine uterus, as well as in the pseudopregnant murine uterus, during the peri-implantation period. Immunohistochemical analysis revealed increases in NPY expression in luminal and glandular epithelial cells and decidualised stromal cells. Neuropeptide Y mRNA expression was strongly induced in cultured epithelial cells in response to sex steroids. The data suggest that NPY is involved in cell–cell interactions during embryonic implantation.
Modulatory effect of leptin on nitric oxide production and lipid metabolism in term placental tissues from control and streptozotocin-induced diabetic rats
Authors: White Verónica , González Elida , Capobianco Evangelina , Pustovrh Carolina , Soñez Carlos , Romanini María Cristina , Jawerbaum Alicia
Published: May 2004

Leptin production by placental tissues contributes to its circulating levels and functions. The diabetic pathology induces alterations in leptin levels. In the present study, leptin levels were evaluated in placental tissue from control and neonatal streptozotocin-induced (n-STZ) diabetic rats during late gestation. The effects of leptin levels on the generation of nitric oxide (NO), prostaglandin (PG) E2 production and lipid metabolism were examined. Leptin levels were diminished in placentas from n-STZ diabetic rats compared with controls (P < 0.01). These differences were also evident when leptin was evaluated immunohistochemically. Addition of leptin (1 nm) in vitro enhanced NO production in control (66%) and diabetic placentas (134%) by stimulating NO synthase activity (by 38% and 54%, respectively). The addition of leptin increased PGE2 production in placentas from control (173%) and diabetic rats (83%) and produced a 50% decrease in placental lipid levels (phospholipids, triacylglycerides, cholesterol and cholesteryl ester) without involving a reduction in de novo lipid synthesis. These data indicate that leptin enhances the production of placental NO and PGE2, vasoactive agents that modify placental blood flow, and that leptin stimulates placental lipid metabolism, probably generating more lipids for transfer to the fetus. In the diabetic rat, placental leptin was reduced, probably as a response to the maternal environment to locally regulate the transfer of nutrients to the developing fetus.
Genome multiplication is a generalised phenomenon in placentomal and interplacentomal trophoblast giant cells in cattle
Authors: Klisch Karl , Thomsen Preben D. , Dantzer Vibeke , Leiser Rudolf
Published: May 2004

The frequency of polyploidisation in bovine binucleate trophoblast giant cells (TGC) from placentomes (PL) and the interplacentomal allantochorion (AL) of six male fetuses with a crown–rump length between 3.5 and 103 cm was determined by in situ hybridisation with a chromosome-7-specific probe, using a probe specific for the Y chromosome to distinguish between maternal and fetal nuclei. The results showed that polyploid nuclei were essentially always of fetal origin. The frequency of tetraploid nuclei varied between 3% and 15% in both the placentomal and interplacentomal samples, with mean frequencies of 8.8% and 10.0% respectively. Octoploid nuclei were observed with a mean frequency of 1.1% in the interplacentomal samples, but were absent in samples from placentomes. Subsequent determination of nuclear DNA content by cytophotometric measurement of Feulgen-stained nuclei revealed that the frequency of nuclei with an 8C DNA content was several fold higher (AL 5.4%; PL 7.8%) than the frequency of octoploidy, suggesting that tetraploid TGC cells are arrested in the G2 phase of the cell cycle.
Lysine fortification reduces anxiety and lessens stress in family members in economically weak communities in Northwest Syria
Authors: Smriga Miro , Ghosh Shibani , Mouneimne Youssef , Pellett Peter L. , Scrimshaw Nevin S.
Published: May 2004

Lysine is a limiting amino acid in diets based on wheat as the staple. In experimental animals, prolonged dietary lysine inadequacy increases stress-induced anxiety. If observed in humans, such a result would have a strong implication for the relationship between nutrition and communal quality of life and mental health. As part of a 3-month randomized double-blind study, we tested whether lysine fortification of wheat reduces anxiety and stress response in family members in poor Syrian communities consuming wheat as a staple food. In the lysine-fortified group, the plasma cortisol response to the blood drawing as a cause of stress was reduced in females, as was sympathetic arousal in males as measured by skin conductance. Lysine fortification also significantly reduced chronic anxiety as measured by the trait anxiety inventory in males. These results suggest that some stress responses in economically weak populations consuming cereal-based diets can be improved with lysine fortification.
An actin-like gene can determine cell polarity in bacteria
Authors: Gitai Zemer , Dye Natalie , Shapiro Lucy
Published: May 2004

Achieving proper polarity is essential for cellular function. In bacteria, cell polarity has been observed by using both morphological and molecular markers; however, no general regulators of bacterial cell polarity have been identified. Here we investigate the effect on cell polarity of two cytoskeletal elements previously implicated in cell shape determination. We find that the actin-like MreB protein mediates global cell polarity inCaulobacter crescentus, although the intermediate filament-like CreS protein influences cell shape without affecting cell polarity. MreB is organized in an axial spiral that is dynamically rearranged during the cell cycle, and MreB dynamics may be critical for the determination of cell polarity. By examining depletion and overexpression strains, we demonstrate that MreB is required both for the polar localization of the chromosomal origin sequence and the dynamic localization of regulatory proteins to the correct cell pole. We propose that the molecular polarity inherent in an actin-like filament is translated into a mechanism for directing global cell polarity.
Gene knockout of glycine transporter 1: Characterization of the behavioral phenotype
Authors: Tsai Guochuan , Ralph-Williams Rebecca J. , Martina Marzia , Bergeron Richard , Berger-Sweeney Joanne , Dunham Kevin S. , Jiang Zhichun , Caine S. Barak , Coyle Joseph T.
Published: May 2004

N
-methyl-
d
-aspartate receptor (NMDAR) activation requires both the binding of glutamate to its recognition site and occupancy of the strychnine insensitive glycine modulatory site (GMS). Pharmacological studies suggest that the glycine transporter, GlyT1, maintains subsaturating concentrations of glycine at synaptic NMDARs. To characterize further the role of GlyT1, we generated mice in which the gene encoding GlyT1 was inactivated by homologous recombination through insertion of a PGK-Neo cassette in place of exons 2 and 3. Real-time quantitative PCR revealed no transcripts in newborn homozygous [GlyT1(-/-)] mice and a 50% reduction in heterozygous (HZ) [GlyT1(+/-)] mice as compared with WT littermates. The activity of Na
+
-dependent glycine transport in forebrain homogenates was similarly affected. Homozygous mice died within 12 h of birth. In acute hippocampal slices, exogenous glycine or
d
-serine (10 μM) enhanced NMDAR currents with Schaffer collateral stimulation in WT mice but not HZ mice, suggesting that the GMS was more occupied in the latter. The NMDAR/α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor ratio of the excitatory postsynaptic currents was significantly increased in the HZ mice. In the water maze, the HZ mice exhibited better spatial retention. Furthermore, HZ mice were less sensitive to an amphetamine disruption of prepulse inhibition than WT mice but were more sensitive to the effects of MK-801. Thus, reduced expression of GlyT1 enhances hippocampal NMDAR function and memory retention and protects against an amphetamine disruption of sensory gating, suggesting that drugs which inhibit GlyT1 might have both cognitive enhancing and antipsychotic effects.
Structural basis for the attachment of a paramyxoviral polymerase to its template
Authors: Kingston Richard L. , Hamel Damon J. , Gay Leslie S. , Dahlquist Frederick W. , Matthews Brian W.
Published: May 2004

The nucleocapsid of measles virus is the template for viral RNA synthesis and is generated through packaging of the genomic RNA by the nucleocapsid protein (N). The viral polymerase associates with the nucleocapsid through a small, trihelical binding domain at the carboxyl terminus of the phosphoprotein (P). Translocation of the polymerase along the nucleocapsid during RNA synthesis is thought to involve the repeated attachment and release of the binding domain. We have investigated the interaction between the binding domain from measles P (amino acids 457–507) and the sequence it recognizes within measles N (amino acids 477–505). By using both solution NMR spectroscopy and x-ray crystallography, we show that N
487–503
binds as a helix to the surface created by the second (α2) and third (α3) helices of P
457–507
, in an orientation parallel to the helix α3, creating a four-helix bundle. The binding interface is tightly packed and dominated by hydrophobic amino acids. Binding and folding of N
487–503
are coupled. However, when not bound to P, N
487–503
does not resemble a statistical random coil but instead exists in a loosely structured state that mimics the bound conformation. We propose that before diffusional encounter, the ensemble of accessible conformations for N
487–503
is biased toward structures capable of binding P, facilitating rapid association of the two proteins. This study provides a structural analysis of polymerase–template interactions in a paramyxovirus and presents an example of a protein–protein interaction that must be only transiently maintained as part of its normal function.
High level HPV‐16 E7 oncoprotein expression correlates with reduced pRb‐levels in cervical biopsies
Authors: Fiedler Marc , Müller‐Holzner Elisabeth , Viertler Hans‐Peter , Widschwendter Andreas , Laich Andreas , Pfister Gerald , Spoden Gilles A. , Jansen‐Dürr Pidder , Zwerschke Werner
Published: May 2004

High‐risk human papillomaviruses (HPVs) are major etiological agents of cervical cancer. Despite excellent epidemiological evidence for a direct role of HPV‐16 in cervical carcinogenesis, molecular pathways underlying carcinogenesis in vivo remain obscure. The E7 gene is required for immortalization and maintenance of the transformed phenotype in vitro; however, little is known about its role for tumorigenesis in vivo. The E7 gene codes for an unstable protein the abundance of which in cervical biopsies is unknown. We show here that E7 protein levels strongly increase during cervical carcinogenesis, underlining its fundamental role in cervical cancer. The E7 protein was found predominantly in the nucleus and to a minor extent in the cytoplasm in the cervical cancer cell line Ca Ski in vitro and in invasive cervical carcinoma in situ, suggesting that nuclear resident E7 plays a major role in cervical carcinogenesis in humans. The retinoblastoma protein (pRb) is a major E7‐target in vitro. We show here that pRb expression is initially upregulated in LSIL and disappears in later stages concomitant with increased E7 levels, suggesting that E7‐driven degradation of pRb is involved in cervical tumorigenesis in humans.
A Pilot Study of Quantitative Aspiration in Patients with Symptoms of Obstructive Sleep Apnea: Comparison to a Historic Control Group
Authors: Beal Michael , Chesson Andrew , Garcia Thomas , Caldito Gloria , Stucker Fred , Nathan Cherie‐Ann
Published: May 2004

Objective: It has been shown that many healthy people aspirate secretions at night. Patients with obstructive sleep apnea (OSA) have frequent episodes of gasping at night that may predispose them to aspiration. The purpose of this study was to determine whether patients with symptoms of OSA are predisposed to pharyngeal aspiration.

Study Design: A prospective study in which patients with symptoms of OSA were compared with a historic group of normal controls by using the same methodology.

Methods: The study was offered to patients with symptoms of OSA undergoing a sleep study. The radiotracer Technicium99 was infused through a plastic tube placed in the nasopharynx after the patient achieved stage II sleep. A chest radionuclide scan determined the amount of material aspirated. The Wilcoxon‐rank sum test was used to compare the mean amount aspirated between the experimental and historic control groups.

Results: Fourteen patients successfully completed the study. One normal volunteer in our study aspirated a quantity similar to the historic normal control group. The amount of aspirated material in the study group ranged from 0.152 to 3.648 mL, with a mean of 1.24 mL ± 0.905 (SD). When compared with the historic normal control group, the patients with symptoms of OSA aspirated significantly more radio‐tracer (P <.01). There was a lack of association between respiratory disturbance index and amount aspirated.

Conclusions: The results suggest there is an apparent risk of increased pharyngeal aspiration in patients with symptoms of OSA.
Impact of Pneumococcal Polysaccharide Vaccine (Prevnar) on Middle Ear Fluid in Children Undergoing Tympanostomy Tube Insertion
Authors: Caspary Hans , Welch J. Camille , Lawson Louise , Darrow David , Buescher Stephen , Shahab Sohrab , Derkay Craig S.
Published: May 2004

Objectives: The purpose of this study was to describe the bacteriology of middle ear effusions in children who have received the pneumococcal polysaccharide vaccine (Prevnar) compared with unvaccinated children.

Methods: A prospective review of medical records from July 2001 to July 2002 was conducted on children with middle ear effusion at time of tympanostomy tube insertion. Middle ear fluid was plated onto culture media immediately after acquisition, and antimicrobial resistance of cultured organisms along with serotyping of Streptococcus pneumoniae was examined. Vaccination status, demographics, and risk factors were determined from patients' medical records, parent interviews, or contact with their primary care physicians.

Results: After adjusting for age and number of previous infections, children vaccinated with Prevnar are two times less likely to have non‐S. pneumoniae pathogenic bacteria isolated than children not vaccinated. Of those with growth, vaccinated children were almost three times more likely than nonvaccinated children to have the presence of H. influenzae. Vaccinated children with H. influenzae were 7.5 times less likely to have β‐lactamase producing H. influenzae than nonvaccinated children with H. influenzae.

Conclusion: Because the incidence of S. pneumoniae was low, no inference could be made whether Prevnar decreased otitis media with effusion or recurrent acute otitis caused by the S. pneumoniae serotypes covered by the vaccine. However, vaccinated children did appear to have the unexpected benefit of having a certain level of protection to growth of typical acute otitis media pathogens.
Analysis of Chromosomes 8 and 17 Aneuploidies in Laryngeal Squamous Cell Carcinoma by Fluorescence In Situ Hybridization
Authors: Öztürk Kayhan , Acar Hasan , Durmuş Ercan , Öztürk Adnan , Mutlu Necip
Published: May 2004

Objectives/Hypothesis: The objectives were to investigate chromosomes 8 and 17 numerical aberrations by using fluorescence in situ hybridization in laryngeal squamous cell carcinoma and also to determine whether there is any association between chromosomes 8 and 17 aneuploidies and TNM classification and subgroups of laryngeal squamous cell carcinomas.

Study Design: Descriptive study.

Methods: Tumor and control samples were taken from 23 patients with LSCC by surgical operation. Fluorescence in situ hybridization analysis with chromosomes 8‐ and 17‐specific α‐satellite DNA probes was performed on the interphase nuclei.

Results: The percentages for chromosomes 8 and 17 aneuploidies were 33% (SD = 25.7%) (median value, 26.2%; range, 3.5%–81.8%) and 19.2% (SD = 15.8%) (median value, 9.8%; range, 3.6%–63.7%), respectively. There was a significant difference between stage 2 and stage 3 (P < .05) and between stage 2 and stage 4 for chromosome 8 aneuploidy (P < .05) but not for chromosome 17 aneuploidy (P > .05). There was also a significant difference for the T classification for chromosome 8 aneuploidy (P < .05) but not for chromosome 17 (P > .05).

Conclusion: Chromosome 8 aneuploidy may be related to stage and T classification of laryngeal squamous cell carcinoma and its progression.
Epstein‐Barr Virus in Head and Neck Cancer Assessed by Quantitative Polymerase Chain Reaction
Authors: Goldenberg David , Benoit Nicole E. , Begum Shahnaz , Westra William H. , Cohen Yoram , Koch Wayne M. , Sidransky David , Califano Joseph A.
Published: May 2004

Objectives/Hypothesis: Epstein‐Barr virus (EBV) has classically been associated with nasopharyngeal carcinoma and Burkitt's lymphoma. Recently, multiple studies have been published linking EBV with oral squamous cell carcinoma and, to a lesser extent, hypopharyngeal and laryngeal tumors. Using a sensitive method of detection, the authors sought to analyze the presence and quantity of EBV DNA in a large cohort of head and neck cancers.

Study Design: Retrospective cohort study.

Methods: Three hundred head and neck cancer samples exclusive of nasopharyngeal carcinoma were examined for the presence of EBV using quantitative polymerase chain reaction. Eighty‐four tumor samples from the larynx, 30 from the hypopharynx, 73 from the oropharynx, and 113 from the oral cavity were analyzed for EBV quantity, which was expressed as the number of viral copies per cell genome. Representative samples, which contained the highest EBV DNA levels, were examined using in situ hybridization. Results were correlated with tumor grade and site and tobacco and alcohol exposure.

Results: Three of 300 (1%) tumor samples were overtly positive for EBV DNA (defined as >0.1 copies of viral DNA/cell genome). Five of 300 (2%) tumor samples showed low levels (defined as >0.01 and <0.1 copies of viral DNA/cell genome), and 68 of 300 tumor samples (23%) showed trace levels (defined as < 0.01 copies of viral DNA/cell genome) of EBV DNA. No correlation was found between EBV positivity and tobacco exposure, alcohol exposure, or tumor grade.

Conclusion: In the overwhelming majority of head and neck cancers in this North American cohort, EBV did not appear to contribute to growth of a dominant clonal population with integrated EBV genome and was unlikely to be a genetic etiological agent in tumor development. The low quantities of EBV detected in a minority of head and neck cancers may be related to the presence of EBV genome in rare lymphoid or epithelial cells adjacent to the primary head and neck cancer.