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Selected AbstractsCryopreservation of vascularized ovary: An evaluation of histology and function in ratsMICROSURGERY, Issue 5 2008Shijie Qi M.D. Cryopreservation of organs has been investigated to sustain the reproductive function of patients undergoing sterilizing chemotherapy and radiotherapy or reproductive surgery. A modified protocol for whole organ cryopreservation was described and the outcome of cryopreservative ovaries was evaluated, and apoptosis of cryopreservative cells stored for different time period and the viability of cryopreserved cells stored at different temperature was examined in rats. Lewis rat ovarian grafts were perfused for 30 min at 0.35 ml/min with M2 medium containing 0.1M fructose and increasing concentrations of 0,1.5M dimethylsulfoxide, cooled to ,140°C controlled by a computerized program, and stored in liquid nitrogen (,196°C) for 24 hours. After being thawed, ovaries were transplanted to syngeneic recipients after bilateral oophorectomy. Graft functions were monitored postoperatively. The major findings were that: 1) A 100% survival rate of rat ovaries was achieved in this study. Ovarian hormone secretion recovered in 80% rats which had received cryopreservative ovarian grafts. Postoperative serum estradiol levels in the cryopreservative graft group were lower than in the sham surgery control, but much higher than in the bilateral oophorectomy group. 2) Histological examination of cryopreservative ovarian grafts showed preantral and antral follicles. Two gestations were obtained. 3) Estradiol levels remained low in ovariectomized rats while in the oophorectomized rats given cryopreservative ovarian grafts levels started to rise after 14 ± 3 days. 4) The average viability in the cells from cryopreservative ovary organ (,196°C) was about 71 ± 18% compared to 90 ± 9% of fresh cells. This success should encourage further improvement of cryopreservative techniques for large organs. © 2008 Wiley-Liss, Inc. Microsurgery, 2008. [source] Effect of citric acid and 1,2-dihydroxybenzene 3,5-disulfonic acid on crystallization of calcium sulfate dihydrate under simulated conditions of phosphoric acid productionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005M. M. Rashad Abstract The effect of citric acid and 1,2-dihydroxybenzene 3,5-disulfonic acid (DHBDSA), as additives, on the crystallization of gypsum was studied under simulated conditions of the of phosphoric acid production. Calcium hydrogen phosphate and sulfuric acid were mixed with dilute phosphoric acid at 80 °C, and the turbidity of the reaction mixture was measured at different time periods to calculate the induction time of gypsum crystals formation. Addition of citric acid increased the induction time and decreased the growth efficiency while addition of DHBDSA decreased the induction time and increased the growth efficiency compared with in absence of additives. The crystals mean and median diameters were found to decrease in the presence of citric acid and increased in the presence of DHBDSA. The surface energy decreased with citric acid and increased with DHBDSA compared to the baseline (without additives). Interestingly, the majority of the formed crystals are tabular with DHBDSA and needle-like type with citric acid and baseline [source] Regulation of Homer and group I metabotropic glutamate receptors by nicotineEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2005J. K. Kane Abstract The present study focuses on the nicotine-induced modulation of mRNA and protein expression of a number of genes involved in glutamatergic synaptic transmission in rat brain over different time periods of exposure. A subchronic (3 days) but not the chronic (7 or 14 days) administration of nicotine resulted in the up-regulation of Homer2a/b mRNA in the amygdala while in the ventral tegmental area (VTA) no change in expression of either Homer2a/b or Homer1b/c was observed. Although the increase in Homer2a/b mRNA was not translated into the protein level in the amygdala, a slight but significant up-regulation of Homer1b/c protein was observed in the same region at day 3. Both Homer forms were up-regulated at the protein level in the VTA at day 3. In the nucleus accumbens, 14 days of nicotine treatment up-regulated mRNA of Homer2b/c by 68.2% (P < 0.05), while the short form Homer1a gene was down-regulated by 65.0% at day 3 (P < 0.05). In regard to other components of the glutamatergic signalling, we identified an acute and intermittent increase in the mRNA and protein levels of mGluR1 and mGluR5 in the amygdala. In the VTA, however, the effects of nicotine on mGluR mRNA expression were long-lasting but rather specific to mGluR1. Nevertheless, mGluR1 protein levels in the VTA area were up-regulated only at day 3, as in the amygdala. These data provide further evidence for the involvement of nicotine in the glutamatergic neuronal synaptic activity in vivo, suggesting a role for the newly identified Homer proteins in this paradigm. [source] Spatial clustering of childhood cancer in Great Britain during the period 1969,1993INTERNATIONAL JOURNAL OF CANCER, Issue 4 2009Richard J.Q. McNally Abstract The aetiology of childhood cancer is poorly understood. Both genetic and environmental factors are likely to be involved. The presence of spatial clustering is indicative of a very localized environmental component to aetiology. Spatial clustering is present when there are a small number of areas with greatly increased incidence or a large number of areas with moderately increased incidence. To determine whether localized environmental factors may play a part in childhood cancer aetiology, we analyzed for spatial clustering using a large set of national population-based data from Great Britain diagnosed 1969,1993. The Potthoff-Whittinghill method was used to test for extra-Poisson variation (EPV). Thirty-two thousand three hundred and twenty-three cases were allocated to 10,444 wards using diagnosis addresses. Analyses showed statistically significant evidence of clustering for acute lymphoblastic leukaemia (ALL) over the whole age range (estimate of EPV = 0.05, p = 0.002) and for ages 1,4 years (estimate of EPV = 0.03, p = 0.015). Soft-tissue sarcoma (estimate of EPV = 0.03, p = 0.04) and Wilms tumours (estimate of EPV = 0.04, p = 0.007) also showed significant clustering. Clustering tended to persist across different time periods for cases of ALL (estimate of between-time period EPV = 0.04, p =0.003). In conclusion, we observed low level spatial clustering that is attributable to a limited number of cases. This suggests that environmental factors, which in some locations display localized clustering, may be important aetiological agents in these diseases. For ALL and soft tissue sarcoma, but not Wilms tumour, common infectious agents may be likely candidates. © 2008 Wiley-Liss, Inc. [source] Global atmospheric energetics from NCEP,Reanalysis 2 and ECMWF,ERA40 ReanalysisINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2009Carlos A. F. Marques Abstract The global atmospheric energy cycle is estimated on an annual basis using Reanalysis 2 data from the National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR), and ERA 40 Reanalyses from the European Centre for Medium-Range Weather Forecasts (ECMWF) for the period 1979,2001. A formalism to avoid belowground data on pressure levels intercepted by topography is adopted. No appreciable differences were found between the two datasets from the energetics point of view. The so-called ,, and v·grad z formulations were both used for the conversions from zonal available potential energy into zonal kinetic energy (CZ) and from eddy available potential energy into eddy kinetic energy (CE). Results with both formulations are comparable only when using the formalism preventing belowground data to enter into the computations. Atmospheric energetics are also computed using ECMWF Reanalyses for the period 1958,1978. A significant increase was found in the eddy kinetic and eddy available potential energies from the early period to the later period, likely related to the assimilation in the reanalyses of satellite data after 1979. The conversion rate, CZ, was found to change its sign throughout the years. The atmospheric energy cycle using the ECMWF Reanalyses data is compared with five previous estimates. Differences in the direction of the conversion rate, CZ, between the various estimates may be explained by the different time periods chosen for averaging. Owing to the omission of belowground data, the conversion from zonal available potential energy into eddy available potential energy (CA) was somewhat smaller in ECMWF Reanalyses than in the previous estimates. Despite those differences, an overall agreement may be found between the various estimates for the atmospheric energy cycle. Copyright © 2008 Royal Meteorological Society [source] Changes in temperature extremes over Italy in the last 44 yearsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2008Andrea Toreti Abstract Changes in temperature extremes over Italy from 1961 to 2004 were evaluated on the basis of minimum and maximum temperatures measured by 49 synoptic stations uniformly distributed over the country. A set of extreme temperature indices of the Commission for Climatology/Climate Variability and Predictability (CCl/CLIVAR) Working Group on Climate Change Detection was calculated and statistically analysed in order to detect the presence of trends and quantify the variations of the indices for different time periods. Most of the indices, averaged over all stations, show a cooling trend until the end of the 1970s followed by a more pronounced warming trend in the last 25 years. The net variation of the indices reflects an increase in the extremes of the temperature distribution. Among the most significant results, an average increase of 12.3 summer days and 12.4 tropical nights in the overall 44 years are estimated. No significant differences between northern, central and southern Italy are found for most indices, indicating that the trends originate from large-scale climate features; however, the largest increase of tropical nights is observed at coastal stations. Copyright © 2007 Royal Meteorological Society [source] US Outward Foreign Direct Investment in the European Union and the Implementation of the Single Market: Empirical Evidence from a Cohesive FrameworkJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 5 2008FRAGKISKOS FILIPPAIOS In this article we investigate the determinants of US outward Foreign Direct Investment (FDI) in the European Union for the period 1982,2002. The data set allowed us to discern differences in the pattern of US FDI between EU core and EU periphery countries, as well as over different time periods during the last two decades. The results indicate that the US FDI pattern varies among different groups of countries and that there was a restructuring in multinational firms' investment activity after the implementation of the single market plan. Agglomeration factors, market size, qualified and productive labour and cost efficiency of local production seem to dominate in the location choice of US investors. [source] Climate change can alter competitive relationships between resident and migratory birdsJOURNAL OF ANIMAL ECOLOGY, Issue 6 2007MARKUS P. AHOLA Summary 1Climate change could affect resource competition between resident and migratory bird species by changing the interval between their onsets of breeding or by altering their population densities. 2We studied interspecific nest-hole competition between resident great tits and migrant pied flycatchers in South-Western Finland over the past five decades (1953,2005). 3We found that appearance of fatal take-over trials, the cases where a pied flycatcher tried to take over a great tit nest but was killed by the tit, increased with a reduced interspecific laying date interval and with increasing densities of both tits and flycatchers. The probability of pied flycatchers taking over great tit nests increased with the density of pied flycatchers. 4Laying dates of the great tit and pied flycatcher are affected by the temperatures of different time periods, and divergent changes in these temperatures could consequently modify their competitive interactions. Densities are a result of reproductive success and survival, which can be affected by separate climatic factors in the resident great tit and trans-Saharan migrant pied flycatcher. 5On these bases we conclude that climate change has a great potential to alter the competitive balance between these two species. [source] Wildfires and the expansion of threatened farmland birds: the ortolan bunting Emberiza hortulana in Mediterranean landscapesJOURNAL OF APPLIED ECOLOGY, Issue 4 2008Lluís Brotons Summary 1It has been argued that wildfires are one of the major agents involved in landscape transformation in many European regions and their impact is expected to increase in the near future. Despite the recognized impact of fire on wildlife at a local scale, we lack information on the species responses to fire at larger spatial scales. 2In this study, we used the ortolan bunting Emberiza hortulana to evaluate the potential effects of wildfires on open-habitat species distribution. In contrast to most European countries, this farmland species has experienced a consistent range expansion during the last decades in Catalonia (northeast Iberian peninsula). Distribution data of the species collected at different time periods allowed us to test the role of fires in determining range expansions at a regional scale, and to evaluate the importance of dispersal constraints on distribution changes. 3Analyses of distribution data from 1975,1983 and 1999,2002 showed a consistent expansion of the ortolan bunting in Catalonia. After correcting for differences in sampling effort, changes in distribution showed a strong spatial pattern with colonization and stability, but not local extinction, being clumped in space. Patterns of change were also strongly and significantly associated with the amount of shrubland burnt between the two time periods, since areas that experienced a larger impact of fires in terms of burnt area showed a much higher probability of maintaining species presence or of being colonized. Colonization events appeared to be more likely in areas affected by fire especially when surrounding areas had already been colonized by the species. 4Synthesis and applications. Overall, our results support the hypothesis that wildfires, especially those affecting open woodlands or shrubby areas, play a critical role in the ecology of the ortolan bunting and have contributed to the recent expansion of the species in Catalonia. Furthermore, we have shown that colonization appears to be limited, not only by the availability of new burnt habitat but also by specific dispersal constraints. We suggest that, for several European threatened species associated with open habitats, burnt areas may partially compensate for the widespread loss and deterioration of farmland habitat, opening new management opportunities for their conservation. [source] Estimated migration rates under scenarios of global climate changeJOURNAL OF BIOGEOGRAPHY, Issue 7 2002Jay R. Malcolm Aim Greenhouse-induced warming and resulting shifts in climatic zones may exceed the migration capabilities of some species. We used fourteen combinations of General Circulation Models (GCMs) and Global Vegetation Models (GVMs) to investigate possible migration rates required under CO2 -doubled climatic forcing. Location Global. Methods Migration distances were calculated between grid cells of future biome type x and nearest same-biome-type cells in the current climate. In `base-case' calculations, we assumed that 2 × CO2 climate forcing would occur in 100 years, we used ten biome types and we measured migration distances as straight-line distances ignoring water barriers and human development. In sensitivity analyses, we investigated different time periods of 2 × CO2 climate forcing, more narrowly defined biomes and barriers because of water bodies and human development. Results In the base-case calculations, average migration rates varied significantly according to the GVM used (BIOME3 vs. MAPSS), the age of the GCM (older- vs. newer-generation GCMs), and whether or not GCMs included sulphate cooling or CO2 fertilization effects. However, high migration rates (, 1000 m year,1) were relatively common in all models, consisting on average of 17% grid cells for BIOME3 and 21% for MAPSS. Migration rates were much higher in boreal and temperate biomes than in tropical biomes. Doubling of the time period of 2 × CO2 forcing reduced these areas of high migration rates to c. 12% of grid cells for both BIOME3 and MAPSS. However, to obtain migration rates in the Boreal biome that were similar in magnitude to those observed for spruce when it followed the retreating North American Glacier, a radical increase in the period of warming was required, from 100 to >1000 years. A reduction in biome area by an order of magnitude increased migration rates by one to three orders of magnitude, depending on the GVM. Large water bodies and human development had regionally important effects in increasing migration rates. Main conclusions In conclusion, evidence from coupled GCMs and GVMs suggests that global warming may require migration rates much faster than those observed during post-glacial times and hence has the potential to reduce biodiversity by selecting for highly mobile and opportunistic species. Several poorly understood factors that are expected to influence the magnitude of any such reduction are discussed, including intrinsic migrational capabilities, barriers to migration, the role of outlier populations in increasing migration rates, the role of climate in setting range limits and variation in species range sizes. [source] Immunophenotypic analysis of human articular chondrocytes: Changes in surface markers associated with cell expansion in monolayer cultureJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2005Jose Diaz-Romero Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) cultured as monolayers undergo changes in phenotype and gene expression known as "dedifferentiation." To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in monolayer culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs cultured in monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in monolayer culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during monolayer culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications. © 2004 Wiley-Liss, Inc. [source] Hypoglycaemia in patients with liver diseases administered levothyroxineJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2003N. Iihara BS Summary Objective: Experience of a few hypoglycaemic patients with liver disease and receiving levothyroxine suggested to us that the prevalence of hypoglycaemia might be higher in such patients. The purpose of this study was to ascertain whether the prevalence of hypoglycaemia this was actually the case. Methods: This study was a retrospective, cross-sectional analysis of a medical computerized database and/or written reports from our university hospital. Patients with primary liver disease who were admitted to our hospital between April 1998 and August 2000 were divided into two groups; the first group received levothyroxine and the second group did not. The patients in the second group were selected from three different time periods within the period shown. The prevalence of hypoglycaemia (blood glucose level <70 mg/dL) was compared between the two groups. Results: The prevalence of hypoglycaemia was significantly higher in the group receiving levothyroxine compared with the group not receiving levothyroxine (four of eight patients (50·0%) vs. three of 59 (5·1%), P = 0·003, Fisher's exact test). Conclusions: The results suggest that levothyroxine may be a risk factor for hypoglycaemia in patients with liver disease. While a larger study, perhaps with an alternative study design is needed to confirm this, and to investigate possible mechanisms of effect, it would be prudent to monitor the blood glucose level of such patients closely. [source] OXYGEN-INHIBITED LAYER IN ADHESION DENTISTRYJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 5 2004Byoung I. Suh MS ABSTRACT Purpose:: Characteristics of the oxygen-inhibited layer, including bond strength, photoinitiator decomposition, and post-curing degree of conversion, were investigated. Materials and Methods: To investigate shear bond strength, BisCover (Bisco, Inc., Schaumburg, IL, USA) and D/E Resin (Bisco, Inc.) were placed on disks of Renew composite (Bisco, Inc.) and cured both with and without an oxygen-inhibited layer. Light-Bond composite (Reliance Orthodontic, Itasca, IL, USA) was placed in a gelatin capsule and light cured over the cured resin. After soaking in water for 2 hours at 37°C, specimens were sheared to failure using a universal testing machine (Model 4466, Instron Inc., Canton, MA, USA). To investigate microtensile bond strength, composite substrates prepared using Renew A2 composite were light cured either in air or under nitrogen. Light-Core (Bisco, Inc.) was placed on each substrate and light cured. The resulting specimens were sectioned into composite beams and stressed to failure using a microtensile tester (built by Bisco, Inc.). To determine camphorquinone (CQ) decomposition, an experimental CQ resin was placed between two glass plates and irradiated for different time intervals. The absorption spectrum was obtained using a Cary 50 Bio UV-Visible Spectrometer (Varian, Mulgrave, Australia). To explore the degree of conversion, polyester film strips (Mylar, DuPont, Wilmington, DE, USA) coated with the CQ resin were pre-cured in air for different time periods, and then post-cured at low intensity for 5 minutes under nitrogen. A Spectrum 1000FTIR Spectrometer (Perkin Elmer, Norwalk, CT, USA) was used to measure the degree of conversion. Results: Bond strength tests resulted in no significant difference between samples with or without an oxygen-inhibited layer. The oxygen-inhibited layer contained reduced amounts of photoinitiator. The degree of conversion of post-cured oxygen-inhibited layers was lower than that for the control. Conclusion: An oxygen-inhibited layer is not necessary for bonding with composite resin. [source] Role of mitogen-activated protein kinases in the mechanism of oxidant-induced cell swelling in cultured astrocytesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 11 2010M. Moriyama Abstract Cytotoxic brain edema, usually a consequence of astrocyte swelling, is an important complication of stroke, traumatic brain injury, hepatic encephalopathy, and other neurological disorders. Although mechanisms underlying astrocyte swelling are not fully understood, oxidative stress (OS) has generally been considered an important factor in its pathogenesis. To better understand the mechanism(s) by which OS causes cell swelling, we examined the potential involvement of mitogen-activated protein kinases (MAPKs) in this process. Cultures exposed to theoxidant H2O2 (10, 25, 50 ,M) for different time periods (1,24 hr) significantly increased cell swelling in a triphasic manner. Swelling was initially observed at 10 min (peaking at 30 min), which was followed by cell shrinkage at 1 hr. A subsequent increase in cell volume occurred at approximately 6 hr, and the rise lasted for at least 24 hr. Cultures exposed to H2O2 caused the activation of MAPKs (ERK1/2, JNK and p38-MAPK), whereas inhibition of MAPKs diminished cell swelling induced by 10 and 25 ,M H2O2. These findings suggest that activation of MAPKs is an important factor in the mediation of astrocyte swelling following oxidative stress. © 2010 Wiley-Liss, Inc. [source] Subcellular localization of beta-catenin in malignant cell lines and squamous cell carcinomas of the oral cavityJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 7 2002A. Gasparoni Abstract Background:, Beta-catenin, an E-cadherin-associated protein involved in cell,cell adhesion and signaling, has been hypothesized to translocate to the nucleus and activate transcription in several human cancers, including oral squamous cell carcinomas (OSCC). Methods:, In the present study, we analyzed the subcellular localization of beta-catenin in cultures of human oral normal and malignant (cell lines SCC15 and SCC25) keratinocytes and in 24 frozen samples of oral squamous cell carcinomas by a double-staining technique for nucleic acids and beta-catenin. Growth potential, as assessed by cell count at different time periods, was established for normal, SCC15 and SCC25 cell lines; oral squamous cell carcinomas were classified according to the histopathological and malignancy indexes. Results:, Beta-catenin localized at the plasma membrane in the normal and SCC15 cells, not in the SCC25 cells, where it localized mostly in the perinuclear and nuclear areas. In the growth assays, SCC25 cell lines proliferated faster than in normal and SCC15 cells over a period of 6 days (cell numbers were significantly different, P < 0.0001). Carcinoma sections showed a combination of membranous, cytoplasmic and, in few invading epithelial islands of two tumors, nuclear localization of beta-catenin. Conclusions:, In oral squamous cell carcinomas, nuclear beta-catenin staining was observed only within invading islands of two carcinomas deep in the underlying connective tissue. On the basis of this study, we conclude that intranuclear beta-catenin does not appear to be a common finding in oral squamous cell carcinomas and that a clear association between intranuclear beta-catenin and histopathological and malignancy indexes in vivo could not be established. [source] in vitro Evaluation of Biodegradable Poly(butylene succinate) as a Novel BiomaterialMACROMOLECULAR BIOSCIENCE, Issue 5 2005Haiyan Li Abstract Summary: Poly(butylene succinate) (PBSU) can be easily synthesized by condensation polymerization of the starting materials of succinic acid and butan-1,4-diol. It has good degradability and possesses excellent processability. Due to these advantages, PBSU was first evaluated in the present study for its potential application as a novel biomaterial. The in vitro biocompatibility of the PBSU was evaluated by monitoring proliferation and differentiation of osteoblasts cultured on the PBSU film substrates for different periods. The results showed that the PBSU was biocompatible as the osteoblasts could proliferate and differentiate on the PBSU plates. In addition, the hydrolytic degradation behavior of the PBSU films in the phosphate-buffered saline (PBS) was also investigated and the results suggested that the PBSU degraded in the PBS solution with the same behavior as that of the degradable poly(, -hydroxyesters). In addition to the biocompatibility and hydrolytic degradation, some physical properties, including hydrophilicity, and mechanical and thermal properties of the PBSU substrates, were also determined and the results revealed that the PBSU was hydrophilic and ductile with excellent processability. The biocompatibility of the PBSU, together with the advantages of hydrolytic degradability, hydrophilicity, and excellent processability, indicated that PBSU has the potential to be used as a biomaterial for tissue repair. Alkaline phosphate activity of osteoblasts cultured on PBSU and TCPS substrates for different time periods. [source] SEASONAL OCCURRENCE OF SPERM WHALE (PHYSETER MACROCEPHALUS) SOUNDS IN THE GULF OF ALASKA, 1999,2001MARINE MAMMAL SCIENCE, Issue 1 2004David K. Mellinger Abstract An acoustic survey for sperm whales was conducted in the Gulf of Alaska. Six autonomous hydrophones continuously recorded sound signals below 500 Hz from October 1999 to May 2001. After recovery, recordings were processed using an automatic process to detect usual clicks of sperm whales. The detection algorithm equalized background noise, summed the data in a frequency band, and then used autocorrelation to detect the whales' highly regular clicks. Detections were checked manually, revealing that 98% of detections did contain clicks. Results indicate that sperm whales are present in the Gulf of Alaska year-round; this result extends what is known from whaling data, which were gathered principally in summer. Sperm whales were more common in summer than winter by a factor of roughly two, and occurred less often at the westernmost site surveyed (52°N, 157°W) than elsewhere in the Gulf. This is the first study of sperm whales based exclusively on remote acoustic sensing. This methodology is feasible because sperm whale clicks extend to frequencies (,100 Hz) low enough to be recorded by low-sample-rate instruments that operate continuously, and because the detection algorithm has a low false-detection rate. The methodology may be replicated to facilitate comparisons between different time periods and geographic regions. [source] Higher expression of hyaluronan binding protein 1 (HABP1/p32/gC1qR/SF2) during follicular development and cumulus oocyte complex maturation in ratMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2008Sonu Chand Thakur Abstract Ovulation is a complex process of releasing a fertilizable oocyte and depends on the proper formation of an extracellular hyaluronan rich matrix by the cumulus oocyte complex (COC). The formation of a HA rich matrix is dependent on the synthesis and organization of HA in the presence of several biomolecules that mediate its crosslinking. To gain an insight into the follicular maturation and COC expansion, we have studied the expression of hyaluronan binding protein 1 (HABP1), which is known to interact specifically with hyaluronan. The level of HABP1 increased markedly during ovulation after gonadotropin stimulation, and the overexpression was seen in mural granulosa cells, expanding cumulus cells and follicular fluid. However, HABP1 could not be detected in the luteal cells of corpus luteum after ovulation. Such increased expression of HABP1 was observed both during in vivo and in vitro conditions of COC expansion. The level of HABP1 transcript was upregulated up to fivefold after COC expansion as compared to compact COC. Immunofluorescence analysis showed HABP1 to be localized in the cytoplasm and extracellular matrix, suggesting its role in ECM organization. The cultured expanded COC treated with hyaluronidase for different time periods showed the gradual dispersion of COC, which coincide with the loss of HABP1 from the matrix suggesting that HABP1 is bound to hyaluronan. These results indicate that HABP1 expressed in rat COCs during maturation may facilitate the formation of the HA matrix in the extracellular space around the oocyte with cumulus expansion during maturation. Mol. Reprod. Dev. 75: 429,438, 2008. © 2007 Wiley-Liss, Inc. [source] Genetic characterization of uniparental lineages in populations from Southwest Iberia with past malaria endemicityAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Vânia Pereira Malaria endemicity in Southwest Iberia afforded conditions for an increase of sickle cell disease (SCD), which in the region follows a clinal pattern toward the south, where foci of high prevalence were found. SCD distribution is associated with specific geographical areas, and therefore, its introduction into Iberia may be related to the migration of different populations. We have analyzed the variation of uniparental markers in Portuguese populations with high frequency of SCD,Coruche, Pias, and Alcacer do Sal,to evaluate if their present-day pattern of neutral diversity could provide evidence about people inhabiting the area over different time periods. Two hundred and eighty-five individuals were sampled in Coruche, Pias, and Alcacer do Sal. All were analyzed for the control region of mitochondrial DNA (mtDNA); males were additionally examined for Y-chromosome markers. Results were then compared with data from other Portuguese and non-Portuguese populations. In Coruche, the genetic profile was similar to the profile usually found in Portugal. In Alcacer do Sal, the frequency of sub-Saharan mtDNA L lineages was the highest ever reported (22%) in Europe. In Pias, mtDNA diversity revealed higher frequencies of Mediterranean haplogroups I, J, and T than usually found in surrounding populations. The presence of Sub-Saharan maternal lineages in Alcacer do Sal is likely associated with the influx of African slaves between the 15th and 19th centuries, whereas in Pias, the Mediterranean influence might be traced to ancient contacts with Greeks, Phoenicians, and Carthaginians, who established important trading networks in southern Iberia. Am. J. Hum. Biol. 22:588,595, 2010. © 2010 Wiley-Liss, Inc. [source] Fluence Rate or Cumulative Dose?PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2007Vulnerability of Larval Northern Pike (Esox lucius) to Ultraviolet Radiation Newly hatched larvae of northern pike were exposed in the laboratory to four fluence rates of ultraviolet radiation (UVR; 290,400 nm) over three different time periods, resulting in total doses ranging from 3.0 ± 0.2 to 63.0 ± 4.4 kJ·m,2. Mortality and behavior of the larvae were followed for 8,12 days, and growth measured at the end of the experiment. Also, the principle of reciprocity,that the UVR-induced mortality depends on the cumulative dose, independent of fluence rate,was tested. Fluence rates higher than 1480 ± 150 mW·m,2 caused mortality and growth retardation. The highest fluence rate (3040 ± 210 mW·m,2) caused 100% mortality in 5 days. All fluence rates caused behavioral disorders, which led to death at fluence rates higher than 1480 mW·m,2. Reciprocity failure occurred with the lowest and highest dose (550 ± 45 and 3040 ± 210 mW·m,2, respectively). The results show that fluence rate is of primary importance when assessing the UVR-related risk. [source] Expression of MHC-I and -II in Uterine Tissue from Early Pregnant BitchesREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009S Schäfer-Somi Contents The aim of the study was to investigate the expression of major histocompatibility complex (MHC)-I and -II in uterine tissues from pregnant and non-pregnant bitches, taken at different time periods after mating. The pregnant bitches were ovariohysterectomized during the pre-implantation (group 1, n = 4), implantation (group 2, n = 7) and placentation stage (group 3, n = 7). Non-pregnant animals in diestrus served as controls (group 4, n = 7). The expression of MHC- I and -II in salpinx, apex, middle horn, corpus uteri and at implantation sites was investigated by immunohistochemistry as well as qualitative and quantitative RT-PCR; MHC-I mRNA was detected in all tissues and with quantitative RT-PCR, and no significant changes were detected until placentation. Immunohistologically, at the apex and corpus site, the average number of MHC-II positive cells increased from the pre-implantation to the post-implantation stage (apex: 1.54 ± 1.21 to 3.82 ± 2.93; corpus: 1.62 ± 1.9 to 5.04 ± 4.95; p < 0.05). The greatest numbers of MHC-II positive cells were observed at placentation sites (6.64 ± 5.9). In parallel, a marked increase in the relative mRNA expression of MHC-II in uterine tissues was assessed from the pre-implantation to the placentation stage (relative to Glycerinaldehyd-3-phosphate-Dehydrogenase (GAPDH): 6.9 ± 9.5, 8.4 ± 5.8, p > 0.05). Immunohistologically, in the salpinx, significantly greater numbers of MHC-II positive cells were found in the tissues of pregnant animals than in the control group (p < 0.05). It is proposed that the increase in MHC-II is pregnancy-related, even though the impact on maintenance of canine pregnancy is still unclear. [source] Agonistic behavior and electrical stimulation of the antennae induces Fos-like protein expression in the male cricket brainARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2010Kaushik Ghosal Abstract Immediate early genes (IEG) such as c-Fos and Fos-related antigens (FRA) have been used as markers of neuronal activation. In this study, we determined whether the expression of c-Fos/FRAs is increased in the brains of adult male Acheta domesticus crickets following agonistic interactions. We looked for c-Fos/FRA proteins in the brain of un-fought, control male crickets and of dominant and subordinate male crickets sacrificed at different time periods following an agonistic interaction. Using immunoblot analysis, we found four different c-Fos/FRA-like proteins in the adult cricket brain. Continuous agonistic interaction increased c-Fos/FRA protein expression in the brains of subordinate males compared to control and dominant males. In addition, direct electrical stimulation of the male cricket antennae increased c-Fos/FRA-like protein in the brain. We identified the specific brain regions that exhibit c-Fos/FRA-like immunoreactivity in crickets. We detected c-Fos/FRA-like cellular immunoreactivity in different functional regions of the adult brain including the pars intercerebralis, protocerebrum, deutocerebrum, and the cortex of the mushroom bodies. © 2010 Wiley Periodicals, Inc. [source] Partitioning of temporal activity among desert lizards in relation to prey availability and temperatureAUSTRAL ECOLOGY, Issue 1 2010CHRISTOPHER E. GORDON Abstract Partitioning of activity time within ecological communities potentially reduces interspecific competition and increases the number of species that can coexist. We investigated temporal activity in a highly diverse lizard assemblage in the Simpson Desert, central Australia, to determine the degree of partitioning that occurs. Three periods were defined, daytime (sunrise to sunset), early night (sunset to midnight) and late night (midnight to sunrise), and live captures of lizards were tallied for each period during two sampling months (September and November 2007). We also quantified the activity times of potential invertebrate prey and measured ambient temperatures during the different time periods to investigate any associations between these factors and lizard activity. Some 77% of captures of 13 lizard species were made by day, with Ctenotus pantherinus, Egernia inornata (Scincidae) and Nephrurus levis (Gekkonidae) the only species showing extended nocturnal activity. Activity of both species of skink was recorded at temperatures 4°C lower than those for agamid and varanid lizards early in the night, and at temperatures as low as 18,20°C. Surface-active invertebrates differed in composition between time periods and were less abundant during the late night period in the drier of the two sample months (September), but were distributed equally over time in the other month. Termites were active in subterranean galleries at night in September and mostly by day in November, but available at all times on surface/subsurface baits. We conclude that activity is distributed unevenly within this lizard assemblage, with partitioning facilitated by the ready availability of invertebrate prey and by lizards having relatively broad temperature tolerances that, in some cases, permit opportunistic exploitation of resources beyond usual times of activity. [source] Maternal mortality and serious maternal morbidity in Jehovah's witnesses in the NetherlandsBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 8 2009ME Van Wolfswinkel Objective, To determine the risk of maternal mortality and serious maternal morbidity because of major obstetric haemorrhage in Jehovah's witnesses in the Netherlands. Design, A retrospective study of case notes. Setting, All tertiary care centres, general teaching hospitals and other general hospitals in the Netherlands. Sample, All cases of maternal mortality in the Netherlands between 1983 and 2006 and all cases of serious maternal morbidity in the Netherlands between 2004 and 2006. Methods, Study of case notes using two different nationwide enquiries over two different time periods. Main outcome measures, Maternal mortality ratio (MMR) and risk of serious maternal mortality. Results, The MMR for Jehovah's witnesses was 68 per 100 000 live births. We found a risk of 14 per 1000 for Jehovah's witnesses to experience serious maternal morbidity because of obstetric haemorrhage while the risk for the total pregnant population was 4.5 per 1000. Conclusions, Women who are Jehovah's witnesses are at a six times increased risk for maternal death, at a 130 times increased risk for maternal death because of major obstetric haemorrhage and at a 3.1 times increased risk for serious maternal morbidity because of obstetric haemorrhage, compared to the general Dutch population. [source] Synergism between fludarabine and rituximab revealed in a follicular lymphoma cell line resistant to the cytotoxic activity of either drug aloneBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2001N. Di Gaetano We have shown previously that the anti-CD20 chimaeric monoclonal antibody rituximab exerts its effects on neoplastic B-lymphoma cell lines in part via complement-dependent cytotoxicity. In addition, membrane expression levels of complement inhibitory proteins CD55 and CD59 play a role in determining susceptibility to lysis. We have identified one t(14;18)-positive human B-cell non Hodgkin's lymphoma cell line (Karpas 422) that is resistant to rituximab and complement and used it for subsequent studies on the possible interaction between this novel therapeutic agent and established antineoplastic drugs. We have exposed Karpas to several chemotherapeutic agents (doxorubicin, idarubicin, cisplatin, taxol) for different time periods and subsequently exposed the cells to rituximab and human complement. The combination of these drugs with rituximab induced an additive cytotoxic effect. In contrast, exposure to fludarabine (1 µg/ml for 48,72 h) showed a synergistic effect, with cell lysis increasing from 10% to 20% using fludarabine or rituximab and complement alone to about 70% with both cytotoxic agents. Analysis of the mechanism for this synergistic effect showed that fludarabine downmodulates the membrane expression of CD55 (from 96% to 55% positive cells) without significantly altering CD20 levels. Northern analysis demonstrated that fludarabine induced a general downmodulation of steady state mRNA levels with no change in transcription rate detected in run-off assays. The study of the effect of fludarabine and rituximab in six freshly isolated B-cell chronic lymphocytic leukaemia (B-CLL) samples showed that, in most cases, fludarabine has an additive cytotoxic activity with rituximab and complement. This report gives a rational support for clinical studies with combinations of drugs, including monoclonal antibodies and fludarabine. [source] Effect of various stabilizing agents on Imperata cylindrica grass pollen allergen extractCLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2003K. M. Bijli Summary Background Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. Objective The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. Methods The Ic extract was kept with 0.1 m,-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 °C, 4 °C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. Results Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. Conclusion EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage. [source] | ||||||||||||||||||||||||||||