bluuebunny/crossref_metadata_2025 huggingface dataset:
Postnatal Changes in the Expression of Claudin‐11 in the Testes and Excurrent Ducts of the Domestic Rabbit (Oryctolagus cuniculus domesticus)
Authors: Park Chan Jin , Lee Jae Eun , Oh Young Seok , Shim Sara , Kim Dong Min , Park Nam Cheol , Park Hyun Jun , Gye Myung Chan
Published: April 2011

ABSTRACT: We examined the expression of claudin‐11 (CLDN11) in the testes and male reproductive tracts of rabbits. The rabbit CLDN11 cDNA sequences were nearly identical with human, mouse, and bovine CLDN11. The levels of CLDN11 mRNA and protein (22 kDa) were markedly increased in the testis during adult development. On postnatal day (PND) 10, CLDN11 was colocalized with ZO‐1 at the lateral contacts between adjacent Sertoli cells and was perpendicular to the basal lamina. In adult testis on PND 180, CLDN11 was codistributed with ZO1, and the pattern of immunoreactivity consisted of wavy linear tracts parallel to the basal lamina, which was different according to the spermatogenic stage. These results suggest that CLDN11 participates in inter–Sertoli cell tight junctions (TJs) at the blood‐testis barrier in adult rabbits. CLDN11 was also found in the basal regions of Sertoli cells adjacent to the basal lamina in adult testis, suggesting that CLDN11 also participates in the adhesion between Sertoli cells and the basal lamina. CLDN11 mRNA and protein expressions were decreased in the adult epididymis compared with those in immature animals. In adults, CLDN11 mRNA levels were relatively high in the efferent duct, followed by those in the vas deferens, proximal corpus, and distal cauda, although low levels were observed in the initial segment and caput. On PND 10, CLDN11 immunoreactivity was identified at the apicolateral contacts between adjacent epithelial cells in the epididymis and vas deferens. In adults, CLDN11 was found in the nonciliated cells in the efferent duct and at the lateral contacts in the epithelial cells in the epididymal segments. In the caput, CLDN11 was found at the apicolateral contacts between adjacent epithelial cells, but expression was weak to negligible in the corpus of the vas deferens. CLDN11 may play an important role in TJs and cell adhesion in immature rabbit excurrent duct epithelia. In adult rabbits, CLDN11 in efferent duct epithelium and epididymal epithelium may contribute to the specific environment for sperm maturation.
Genetically Induced Estrogen Receptor α mRNA (Esr1) Overexpression Does Not Adversely Affect Fertility or Penile Development in Male Mice
Authors: Heath John , Abdelmageed Yazeed , Braden Tim D. , Williams Carol S. , Williams John W. , Paulose Tessie , Hernandez‐Ochoa Isabel , Gupta Rupesh , Flaws Jodi A. , Goyal Hari O.
Published: April 2011

ABSTRACT:Previously, we reported that estrogen receptor α mRNA (Esr1) or protein (ESR1) overexpression resulting from neonatal exposure to estrogens in rats was associated with infertility and maldeveloped penis characterized by reduced length and weight and abnormal accumulation of fat cells. The objective of this study was to determine if mutant male mice overexpressingEsr1are naturally infertile or have reduced fertility and/or develop abnormal penis. The fertility parameters, including fertility and fecundity indices, numbers of days from the day of cohabitation to the day of delivery, and numbers of pups per female, were not altered from controls as a result ofEsr1overexpression. Likewise, penile morphology, including the length, weight, and diameter and os penis development, was not altered from controls. Conversely, weights of the seminal vesicles and bulbospongiosus and levator ani (BS/LA) muscles were significantly (P< .05) lower as compared with controls; however, the weight of the testis, the morphology of the testis and epididymis, and the plasma and testicular testosterone concentration were not different from controls. Hence, genetically inducedEsr1overexpression alone, without an exogenous estrogen exposure during the neonatal period, is unable to adversely affect the development of the penis as well as other male reproductive organs, except for limited, but significant, reductions in weights of the seminal vesicles and BS/LA muscles.
Mechanisms of Fertilization—A View From the Study of Gene‐Manipulated Mice
Authors: Muro Yuko , Okabe Masaru
Published: April 2011

ABSTRACT: Recent gene knockout approaches have revealed that many of the factors previously considered to be important were largely dispensable in gene‐knockout animals, and that previously unknown factors are emerging. Unexpectedly, sperm from 5 different gene‐disrupted mouse lines (calmegin (Clgn), Adam1a, Adam2, Adam3, and Ace) all have defective zona‐binding ability and oviduct‐migrating ability. We have disrupted a new testis‐specific molecular chaperone, calsperin (Calr3), which became the sixth gene sharing the same infertile phenotype. The relationships among these 6 factors are discussed. After zona penetration, sperm needs to fuse with eggs. We reported that sperm require IZUMO1 and eggs require CD9 for sperm‐egg fusion. However, the distribution of IZUMO1 is not limited to the equatorial segment where it is believed the fusion takes place. Therefore, we produced a mouse line that lacks an equatorial segment–specific antigen, Spesp1. The Spesp1 +/– and –/– sperm showed a decreased fusing ability compared with wild‐type sperm, but the cause of the impaired fusion may not directly relate to the mechanism involving IZUMO1. In order to study the mechanism of fertilization, the visualization of sperm in vivo provides a powerful tool. We made a new transgenic mouse line that produces sperm with green fluorescent protein–tagged acrosome and DSRed2‐tagged mitochondria. Studies of fertilization using gene‐manipulated animals are described in the present review.
Differential Proteomics Leads to Identification of Domain‐Specific Epididymal Sperm Proteins
Authors: Suryawanshi Amol R. , Khan Shagufta A. , Gajbhiye Rahul K. , Gurav Mamta Y. , Khole Vrinda V.
Published: April 2011

ABSTRACT: The alteration in the protein signatures of the testicular sperm during its epididymal sojourn makes it functionally competent for successful fertilization. The present study was undertaken to identify the proteins acquired on its 2 domains, that is, the head and the flagellum, during the epididymal transit using a differential proteomics approach. Testicular sperm proteome was compared with cauda epididymal sperm proteome in rat. The protein spots exclusively present in the cauda epididymal sperm proteome were searched in the cauda sperm head proteome and the cauda sperm flagella proteome, and a total of 335 spots were found by alignment and auto‐matching of the gels, of which 140 could be identified by mass spectrometry. Database search revealed that of these 9 proteins were novels. Gene Ontology annotation revealed that the identified proteins were distributed across different cellular components and were primarily involved in metabolic processes. The study also provides information on the localization of these proteins on the sperm domains, which indirectly gives a clue about its putative function. Validation of 3 proteins, namely MMSDH, NDUFS1, and UQCRC2, using antibodies very elegantly demonstrates that the strategy has been very effective. This comprehensive data of domain‐specific epididymal sperm proteins will be useful in development of newer targets for posttesticular contraception and diagnostic markers for infertility.
Protamine/DNA Ratios and DNA Damage in Native and Density Gradient Centrifuged Sperm From Infertile Patients
Authors: Castillo Judit , Simon Luke , de Mateo Sara , Lewis Sheena , Oliva Rafael
Published: April 2011

ABSTRACT: Protamines are the major nuclear proteins condensing DNA in the sperm nucleus. One of their proposed functions is the protection of the genetic message delivered by the sperm. To date, evidence of their involvement in DNA protection has been obtained by correlating the protamine P1/P2 ratio, protamine concentrations, or chromomycin A3 staining with DNA fragmentation. However, a correlation of the absolute protamine/DNA content with the DNA fragmentation in sperm from the same infertile patients as assessed with the comet assay has not been studied. Protamine/DNA ratios were calculated after protamine and DNA extraction, electrophoresis, and gel quantification of the protamines and DNA quantification in the sperm samples of 66 infertile patients before (native sample) and after a 2‐step discontinuous PureSperm density gradient centrifuged (DGC) selection of the sperm. DNA fragmentation was assessed using the alkaline comet assay. In DGC sperm, the total protamine/DNA, P1/DNA, and P2/DNA ratios all correlated inversely with DNA damage in sperm from infertile patients. The detection of this inverse correlation between protamine/DNA ratios and DNA damage in DGC sperm adds support to the hypothesis that defective protamination is related to DNA damage in the clinically relevant subpopulation of sperm from infertile men.
Normoxic Expression of Hypoxia‐Inducible Factor 1 in Rat Leydig Cells In Vivo and In Vitro
Authors: Palladino M. A. , Pirlamarla P. R. , McNamara J. , Sottas C. M. , Korah N. , Hardy M. P. , Hales D. B. , Hermo L.
Published: April 2011

ABSTRACT:Hypoxia‐inducible factors (HIF) are transcription factors that serve essential regulatory roles in cellular and molecular responses to oxygen debt. HIFs are composed of hypoxia‐dependent α subunits (1α, 2α, 3α) and an oxygen‐independent β subunit. Previously we demonstrated that HIF‐1, the master regulator of hypoxic responses, is expressed in the adult rat testis. We hypothesized that HIF‐1 is involved in regulating responses to oxygen tension in the testis. Goals of this study were to determine if HIF‐2α and HIF‐3α are expressed in rat testis, identify testis cell types that express HIF‐1α, and examine patterns of testicular HIF‐1α protein expression under conditions of ischemia and hypoxia in vivo and in vitro. Reverse transcriptase polymerase chain reaction revealed that mRNA forHif‐1α,Hif‐2α, andHif‐3α is expressed in the testis. The HIF‐1α protein is the predominant subunit in testis. HIF‐1α protein was abundant in normoxic testis, and its levels remained unchanged following ischemia created by surgically induced testicular torsion and reperfusion. Immunoblot and immunocytochemical experiments demonstrated that Leydig cells are the major source of HIF‐1α in normoxic and hypoxic testes. To examine potential mechanisms of testicular HIF‐1 stabilization, nuclear proteins from Leydig cells cultured in 5% or 21% oxygen, or cells cultured with H2O2, were analyzed by immunoblotting. Levels of HIF‐1α were significantly diminished in 5% or 21% oxygen cultures compared with freshly isolated cells. Treating Leydig cells with H2O2as a source of reactive oxygen species did not affect HIF‐1α levels. High levels of constitutively expressed HIF‐1α in normoxic Leydig cells suggest potentially unique roles for HIF‐1 in Leydig cell responsiveness to oxygen.
Pre‐treatment of Industrial Wastewater Polluted with Lead Using Adsorbents and Ultrafiltration or Microfiltration Membranes
Authors: Katsou Evina , Malamis Simos , Haralambous Katherine
Published: April 2011

This work investigated the use of ultrafiltration (UF) or microfiltration (MF) membranes combined with natural minerals for the pre‐treatment of wastewater containing high amounts of lead. The effects of initial lead concentration, solution pH, membrane pore size, mineral type and concentration and mineral ‐ metal contact time were investigated. Lead removal accomplished by the UF system was higher in wastewater compared to that obtained in aqueous solutions and this was attributed to the formation of insoluble metal precipitates/complexes, which were effectively retained by the membranes. At pH = 6 the dominant removal mechanism was precipitation/complexation, while mineral adsorption enhanced lead removal. The combined use of minerals and UF/MF membranes can effectively remove lead from wastewater resulting in a final effluent that can be further treated biologically with no biomass inhibition problems or can be safely discharged into municipal sewers. Kinetics investigation revealed a two‐stage diffusion process for all minerals employed. The Langmuir isotherm exhibited the best fit to the experimental data.
Is Phycovolatilization of Heavy Metals a Probable (or Possible) Physiological Phenomenon? An In Situ Pilot‐Scale Study at a Leather‐Processing Chemical Industry
Authors: Rao P. Hanumantha , Kumar R. Ranjith , Raghavan B. G. , Subramanian V. V. , Sivasubramanian V.
Published: April 2011

Using algae to treat industrial effluents containing heavy metals presents an alternative to the current practice of using other biosorbents and physical and chemical methods. In this study, effluent from a leather‐processing chemical industry in Ranipet, Tamil Nadu, India, was treated for the removal of heavy metals using the microalga, Chlorella vulgaris, which was isolated from the effluent itself. The objectives of this study were to (1) assess the mass balance of a model parameter, lead, in laboratory conditions and estimate the lead adsorption capabilities of the microalga and (2) conduct pilot‐scale studies for the removal of heavy metals, using the microalga, from the effluent and the solid waste accumulated over the years generated by conventional treatment methods. The results of the study show that after 8 hours, Chlorella vulgaris exhibited a better adsorption capacity under sunlight compared to laboratory conditions (i.e., 30.6 mg/g dry weight vs 10.5 mg/g dry weight, respectively). Similarly, reduction of heavy metals and mass balance in pilot‐scale field studies conducted in a high‐rate algal pond showed that the microalga, apart from adsorption, complexation, and entrapment mechanisms, is likely to possess phycovolatilization capability probably via biotransformation processes.
Minimum Requirements for Trace Metals (Iron, Nickel, Cobalt, and Zinc) in Thermophilic and Mesophilic Methane Fermentation from Glucose
Authors: Takashima Masanobu , Shimada Kohji , Speece Richard E.
Published: April 2011

The minimum requirements for four essential trace metals were examined in both thermophilic and mesophilic methane fermentation of glucose. The minimum requirement here was defined as the amount that supports the effluent soluble chemical oxygen demand (COD) of 1000 mg/L or less for the duration of several times the hydraulic retention time (HRT). For this purpose, completely mixed reactors were run semi‐continuously at 5 days HRT, with 10 g/L substrate COD. The minimum requirements determined as milligrams per gram COD removed were 0.45, 0.049, 0.054, and 0.24 in the thermophilic system and 0.20, 0.0063, 0.017, and 0.049 in the mesophilic system for iron, nickel, cobalt, and zinc, respectively. The thermophilic system required larger amounts (2.2 to 7.8 times) of the trace metals than the mesophilic system, indicating greater assimilation by biomass and/or less bioavailability under thermophilic conditions. The results can give quantitative information on trace metal nutrition for successful methane fermentation.
Development of a Depth‐Integrated Sample Arm to Reduce Solids Stratification Bias in Stormwater Sampling
Authors: Selbig William R. , Bannerman Roger T.
Published: April 2011

A new depth‐integrated sample arm (DISA) was developed to improve the representation of solids in stormwater, both organic and inorganic, by collecting a water quality sample from multiple points in the water column. Data from this study demonstrate the idea of vertical stratification of solids in storm sewer runoff. Concentrations of suspended sediment in runoff were statistically greater using a fixed rather than multi‐point collection system. Median suspended sediment concentrations measured at the fixed location (near the pipe invert) were approximately double those collected using the DISA. In general, concentrations and size distributions of suspended sediment decreased with increasing vertical distance from the storm sewer invert. Coarser particles tended to dominate the distribution of solids near the storm sewer invert as discharge increased. In contrast to concentration and particle size, organic material, to some extent, was distributed homogenously throughout the water column, likely the result of its low specific density, which allows for thorough mixing in less turbulent water.
Ammonia‐Nitrogen Sorptional Properties of Banana Peels
Authors: Chen Yunnen , Ding Lichao , Fan Jingbiao
Published: April 2011

Using modified banana peel as a biosorbent to treat water containing ammonia‐nitrogen (NH4+‐N) was studied. Related parameters in the sorptional process, such as chemical modification, pH, and contact time were investigaed. The experimental results showed that banana peel modified by 30% sodium hydroxide (NaOH) and mesothermal microwaves (NMBPs) can greatly improve the sorption removal for NH4+‐N. The kinetics study revealed that the sorption behavior better fit the pseudo‐second‐order equation than the Lagergren first‐order equation. Fourier transform infrared absorption spectrum analysis of banana peels and NMBPs before and after NH4+‐N sorption revealed that the activity of hydroxyl groups at the surface of the banana peels was strengthened after modification, and nitrogenous groups appeared after biosorpting the NH4+‐N. In the end, metallurgical wastewater containing a low concentration of NH4+‐N was treated by NMBPs. The initial NH4+‐N concentration of 138 mg/L was reduced to 13 mg/L in 25 minutes by 4 g/L NMBPs at pH 10.
Chabazite Biofilter for Enhanced Stormwater Nitrogen Removal
Authors: Smith Daniel P.
Published: April 2011

Enhanced nitrogen removal from stormwater using chabazite, a natural cation exchanger, was evaluated in a pilot‐plant biofilter operated for 216 days. A parallel sand filter served as the control. The biofilters were subject to various operating modes including baseline periods of steady flowrate and loading, simulated high flowrate (storm) events following steady flowrates, high flowrates following extended no‐flow periods, and with limited influent dissolved oxygen. Under steady‐flow operation, chabazite removed 93% of ammonium and sand removed 87%; total inorganic nitrogen was reduced 35% by chabazite versus 15% by sand. In a simulated storm event following steady‐flow operation, 97% of cumulative ammonia mass was retained by the chabazite biofilter versus 70% for sand. Following a 40 day no‐flow period, the chabazite biofilter retained 98% of influent ammonium in a storm event while sand exhibited high effluent ammonium. Chabazite ammonium retention was high under limited influent dissolved oxygen, verses significant breakthrough by the sand biofilter. Chabazite media provided superior performance resiliency under dynamic conditions that typify stormwater treatment.
Accounting for Individual Differences in Bradley-Terry Models by Means of Recursive Partitioning
Authors: Strobl Carolin , Wickelmaier Florian , Zeileis Achim
Published: April 2011

The preference scaling of a group of subjects may not be homogeneous, but different groups of subjects with certain characteristics may show different preference scalings, each of which can be derived from paired comparisons by means of the Bradley-Terry model. Usually, either different models are fit in predefined subsets of the sample or the effects of subject covariates are explicitly specified in a parametric model. In both cases, categorical covariates can be employed directly to distinguish between the different groups, while numeric covariates are typically discretized prior to modeling. Here, a semiparametric approach for recursive partitioning of Bradley-Terry models is introduced as a means for identifying groups of subjects with homogeneous preference scalings in a data-driven way. In this approach, the covariates that—in main effects or interactions—distinguish between groups of subjects with different preference orderings, are detected automatically from the set of candidate covariates. One main advantage of this approach is that sensible partitions in numeric covariates are also detected automatically.
Climate Change and Individual Responsibility: A Reply to Johnson
Authors: Hourdequin Marion
Published: April 2011

Can unilateral action be an effective response to global climate change? Baylor Johnson worries that a focus on unilateral action by individuals will detract from efforts to secure collective agreements to address the problem. Although Johnson and I agree that individuals have some obligation to reduce their personal emissions, we differ in the degree to which we see personal reductions as effective in spurring broader change. I argue that ‘unilateral reductions’ can have communicative value and that they can change the structure of collective action problems, making such problems easier to solve. Since collective action problems are much less tractable where individuals abide by the tenets of traditional game theory and much more tractable where individuals are oriented to cooperate and to trust that others will reciprocate, we need moral norms that promote individual restraint in exploitation of the commons, and we ought ourselves to abide by those norms.
Valuation Contests over the Commoditisation of the Moabi Tree in South-Eastern Cameroon
Authors: Veuthey Sandra , Gerber Julien-François
Published: April 2011

We analyse the nature of grassroots conflicts over the commercial logging of moabi (Baillonella toxisperma) by foreign firms in South-eastern Cameroon. Moabi offers a good starting point for understanding forest resistances because it crystallises nature conservation, commercial, as well as local interests as it provides oil, medicine and other use values to local populations and particularly to women. Combining a political ecology approach with elements of ecological economics, we find that the conflicts on moabi extraction can be analysed in terms of conflicting languages of valuation – the defence of livelihood and customary institutions versus economic growth and the national laws. We discuss the historical and institutional components of the conflicts as well as the specific role of women.
Biomarkers in Advanced Colorectal Cancer: Challenges in Translating Clinical Research into Practice
Authors: Lemech Charlotte , Arkenau Hendrik-Tobias
Published: April 2011

The growing number of therapeutic agents and known molecular targets in oncology makes the study and clinical use of biomarkers imperative for improving response and survival, reducing toxicity and ensuring economic sustainability. Colorectal cancer, among others, is at the forefront of development of predictive and prognostic biomarkers; however, the difficulty lies in translating potential biomarkers garnered from retrospective analyses in small numbers of patients to generalizable and affordable biomarkers used worldwide. This review outlines the progress made in prognostic and predictive biomarkers in advanced colorectal cancer (ACRC) from the early use of carcinoembryonic antigen (CEA) to the KRAS mutation and beyond. Future challenges are to incorporate standardized and validated methods preferentially during early phases of drug development linked with sophisticated biostatistical support. New trial designs focusing on biomarkers will be essential not only for better understanding of mechanisms of action, but also to make confident ‘go or no-go’ decisions.
Molecular Epidemiology of Female Lung Cancer
Authors: Yim Seon-Hee , Chung Yeun-Jun
Published: April 2011

Lung cancer is still a leading cause of cancer mortality in the world. The incidence of lung cancer in developed countries started to decrease mainly due to global anti-smoking campaigns. However, the incidence of lung cancer in women has been increasing in recent decades for various reasons. Furthermore, since the screening of lung cancer is not as yet very effective, clinically applicable molecular markers for early diagnosis are much required. Lung cancer in women appears to have differences compared with that in men, in terms of histologic types and susceptibility to environmental risk factors. This suggests that female lung cancer can be derived by carcinogenic mechanisms different from those involved in male lung cancer. Among female lung cancer patients, many are non-smokers, which could be studied to identify alternative carcinogenic mechanisms independent from smoking-related ones. In this paper, we reviewed molecular susceptibility markers and genetic changes in lung cancer tissues observed in female lung cancer patients, which have been validated by various studies and will be helpful to understand the tumorigenesis of lung cancer.
Community Forest Management and the Emergence of Multi-Scale Governance Institutions: Lessons for REDD+ Development from Mexico, Brazil and Bolivia
Authors: Cronkleton Peter , Bray David Barton , Medina Gabriel
Published: April 2011

At their most local, initiatives to reduce emissions from deforestation and degradation (REDD) will depend on rural people to manage forest resources. Although the design of frameworks, mechanisms and arrangements, to implement REDD programs have received significant attention, it is not yet clear how REDD+ will function on the ground or how the participation of local populations will be assured. Community forest management (CFM) could be an option under REDD+ depending on how it is negotiated, largely because of the expectation that CFM could reduce emissions from deforestation and degradation. Examining institutional factors in the emergence of successful CFM systems and local forest enterprises could provide valuable lessons for REDD planners. We examine cases of CFM development in Mexico, Brazil and Bolivia, to assess the role of multi-scaled governance institutions in their development. Comparing and contrasting advanced CFM systems to regions where it is still emerging, we will show how the establishment of a local organizational base for communal resource management is crucial.
Insect Pests in Future Forests: More Severe Problems?
Authors: Björkman Christer , Bylund Helena , Klapwijk Maartje J. , Kollberg Ida , Schroeder Martin
Published: April 2011

A common concern is that damage by insects will increase in forests as a consequence of climate change. We are assessing the likelihood of this predicted outcome by examining how other factors (especially changes in forest management practices) may interact with effects of climate change. Here we describe the strategies for improving understanding of the causes of insect outbreaks and predicting the likelihood of insect-mediated damage increasing in the future. The adopted approaches are: (i) analyses of historical data, (ii) comparison of life history traits of outbreak and non-outbreak species, (iii) experiments along climatic gradients to quantify the strength of trophic interactions, and (iv) modeling. We conclude that collaboration by researchers from many disciplines is required to evaluate available data regarding the complex interactions involved, to identify knowledge gaps, and facilitate attempts to progress beyond speculation to more robust predictions concerning future levels of insect damage to forests.
Using Online Tools to Assess Public Responses to Climate Change Mitigation Policies in Japan
Authors: Chay Sengtha , Sasaki Nophea
Published: April 2011

As a member of the Annex 1 countries to the Kyoto Protocol of the United Nations Framework Convention on Climate Change, Japan is committed to reducing 6% of the greenhouse gas emissions. In order to achieve this commitment, Japan has undertaken several major mitigation measures, one of which is the domestic measure that includes ecologically friendly lifestyle programs, utilizing natural energy, participating in local environmental activities, and amending environmental laws. Mitigation policies could be achieved if public responses were strong. As the internet has increasingly become an online platform for sharing environmental information, public responses to the need for reducing greenhouse gas emissions may be assessed using available online tools. We used Google Insights for Search, Google AdWords Keyword Tool, and Google Timeline View to assess public responses in Japan based on the interest shown for five search terms that define global climate change and its mitigation policies. Data on online search interests from January 04, 2004 to July 18, 2010 were analyzed according to locations and categories. Our study suggests that the search interests for the five chosen search terms dramatically increased, especially when new mitigation policies were introduced or when climate change related events were organized. Such a rapid increase indicates that the Japanese public strongly responds to climate change mitigation policies.
Effect of Culture Conditions on Viability of Mouse and Rat Embryos Developed in Vitro
Authors: Popova Elena , Bader Michael , Krivokharchenko Alexander
Published: April 2011

Currently in vitro culture of mouse preimplantation embryos has become a very important technique to investigate different mechanisms of early embryogenesis. However, there is a big difference in the preimplantation development between mammalian species. Despite close relatedness to mice, in vitro cultivation of rat preimplantation embryos is still delicate and needs further investigation and optimizations. In this study we have compared the in vitro developmental potential of mouse and rat embryos cultured at different culture conditions in parallel experiments. Interestingly, mouse zygotes developed in vitro until blastocyst stage even in inadequate medium without any phosphates and with low osmolarity which was formulated especially for cultivation of rat embryos. Rat parthenotes and zygotes developed in M16 medium formulated for mouse embryos only till 2-cell stage and further development is blocked completely at this stage. Moreover, developmental ability of rat embryos in vitro was significantly lower in comparison with mouse even in special rat mR1ECM medium. Mouse and rat embryos at 2-cell stage obtained in vivo developed until blastocyst stages significantly more efficiently compared to zygotes. Culture of mouse zygotes in glass capillaries resulted in a significantly higher rate of morula and blastocyst development compared with dishes. The Well-of-the-Well system resulted in a significant improvement when compared with dishes for the culture of rat zygotes only until morula stage. Reduced oxygen tension increased the developmental rate of rat but not mouse zygotes until blastocyst stage. This study demonstrates that development of early preimplantation embryos is altered by different culture conditions and show strong differences even between two related species such as mice and rats. Therefore, for understanding the fundamental mechanisms of early mammalian development it is very important to use embryos of various species.
A Multidisciplinary, Science-Based Approach to the Economics of Climate Change
Authors: Carlin Alan
Published: April 2011

Economic analyses of environmental mitigation and other interdisciplinary public policy issues can be much more useful if they critically examine what other disciplines have to say, insist on using the most relevant observational data and the scientific method, and examine lower cost alternatives to the change proposed. These general principles are illustrated by applying them to the case of climate change mitigation, one of the most interdisciplinary of public policy issues. The analysis shows how use of these principles leads to quite different conclusions than those of most previous such economic analyses, as follows:

The economic benefits of reducing CO2 emissions may be about two orders of magnitude less than those estimated by most economists because the climate sensitivity factor (CSF) is much lower than assumed by the United Nations because feedback is negative rather than positive and the effects of CO2 emissions reductions on atmospheric CO2 appear to be short rather than long lasting.
The costs of CO2 emissions reductions are very much higher than usually estimated because of technological and implementation problems recently identified.
Geoengineering such as solar radiation management is a controversial alternative to CO2 emissions reductions that offers opportunities to greatly decrease these large costs, change global temperatures with far greater assurance of success, and eliminate the possibility of low probability, high consequence risks of rising temperatures, but has been largely ignored by economists.
CO2 emissions reductions are economically unattractive since the very modest benefits remaining after the corrections for the above effects are quite unlikely to economically justify the much higher costs unless much lower cost geoengineering is used.
The risk of catastrophic anthropogenic global warming appears to be so low that it is not currently worth doing anything to try to control it, including geoengineering.
Characterization of Doped Amorphous Silicon Thin Films through the Investigation of Dopant Elements by Glow Discharge Spectrometry: A Correlation of Conductivity and Bandgap Energy Measurements
Authors: Sánchez Pascal , Lorenzo Olaya , Menéndez Armando , Menéndez Jose Luis , Gomez David , Pereiro Rosario , Fernández Beatriz
Published: April 2011

The determination of optical parameters, such as absorption and extinction coefficients, refractive index and the bandgap energy, is crucial to understand the behavior and final efficiency of thin film solar cells based on hydrogenated amorphous silicon (a-Si:H). The influence of small variations of the gas flow rates used for the preparation of the p-a-SiC:H layer on the bandgap energy, as well as on the dopant elements concentration, thickness and conductivity of the p-layer, is investigated in this work using several complementary techniques. UV-NIR spectrophotometry and ellipsometry were used for the determination of bandgap energies of four p-a-SiC:H thin films, prepared by using different B2H6 and SiH4 fluxes (B2H6 from 12 sccm to 20 sccm and SiH4 from 6 sccm to 10 sccm). Moreover, radiofrequency glow discharge optical emission spectrometry technique was used for depth profiling characterization of p-a-SiC:H thin films and valuable information about dopant elements concentration and distribution throughout the coating was found. Finally, a direct relationship between the conductivity of p-a-SiC:H thin films and the dopant elements concentration, particularly boron and carbon, was observed for the four selected samples.
One-Dimensional Hydrogen-Bonded Infinite Chain from Nickel(II) Tetraaza Macrocyclic Complex and 1,2-Cyclopentanedicarboxylate Ligand
Authors: Lim In-Taek , Choi Ki-Young
Published: April 2011

The reaction of [Ni(L)]Cl2·2H2O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18,07.12]docosane) with trans-1,2-cyclopentanedicarboxylic acid (H2-cpdc) yields a 1D hydrogen-bonded infinite chain with formula [Ni(L)(H-cpdc-)2] (1). This complex has been characterized by X-ray crystallography, spectroscopy and cyclic voltammetry. The crystal structure of 1 exhibits a distorted octahedral geometry about Ni atom with four nitrogen atoms of the macrocycle and two oxygen atoms of the H-cpdc- ligand at the axial position. Compound 1 crystallizes in the monoclinic system P21/c with a = 8.7429(17), b = 10.488(2), c = 18.929(4) Å, β = 91.82(2), V = 1734.8(6) Å3, Z = 2. Electronic spectrum of 1 reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes two waves of a one-electron transfer corresponding to NiII/NiIII and NiII/NiI processes.
RETRACTED: Dextran Sulfate Sodium Inhibits Alanine Synthesis in Caco-2 Cells
Authors: Ye Zhong , Mishchuk Darya O. , Stephens Natasha S. , Slupsky Carolyn M.
Published: April 2011

To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS) has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using 1H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed.
Lead, Cadmium and Cobalt (Pb, Cd, and Co) Leaching of Glass-Clay Containers by pH Effect of Food
Authors: Valadez-Vega Carmen , Zúñiga-Pérez Clara , Quintanar-Gómez Samuel , Morales-González José A. , Madrigal-Santillán Eduardo , Villagómez-Ibarra José Roberto , Sumaya-Martínez María Teresa , García-Paredes Juan Diego
Published: April 2011

Recent studies have shown that handcrafted glass-clay containers are a health risk because they can be contaminated by heavy metals, which can be transferred to food, thus reaching the human body to potentially cause illness. Therefore, in the present work, we evaluate the leaching of lead, cadmium, and cobalt from glass-clay containers into two types of food: tomato sauce (salsa), and chickpea puree. The containers were obtained from four regions in the Mexican state of Hidalgo. Repetitive extractions from the containers were carried out to quantify the leaching of the heavy metals into the salsa, the chickpea puree, and acetic acid using the technique proposed by the USFDA. The results show that greater use of the containers leads to more leaching of heavy metals into both types of food and into the acetic acid, with the greatest metal extraction recorded for the Ixmiquilpan vessels. These results indicate that the metals present in the glass-clay containers leach into the food and that increased reuse increases the risk to the people who use them in food preparation.
Spencer-Brown vs. Probability and Statistics: Entropy’s Testimony on Subjective and Objective Randomness
Authors: Stern Julio Michael
Published: April 2011

This article analyzes the role of entropy in Bayesian statistics, focusing on its use as a tool for detection, recognition and validation of eigen-solutions. “Objects as eigen-solutions” is a key metaphor of the cognitive constructivism epistemological framework developed by the philosopher Heinz von Foerster. Special attention is given to some objections to the concepts of probability, statistics and randomization posed by George Spencer-Brown, a figure of great influence in the field of radical constructivism.
First Evidence of Palytoxin and 42-Hydroxy-palytoxin in the Marine Cyanobacterium Trichodesmium
Authors: Kerbrat Anne Sophie , Amzil Zouher , Pawlowiez Ralph , Golubic Stjepko , Sibat Manoella , Darius Helene Taiana , Chinain Mireille , Laurent Dominique
Published: April 2011

Marine pelagic diazotrophic cyanobacteria of the genus Trichodesmium (Oscillatoriales) are widespread throughout the tropics and subtropics, and are particularly common in the waters of New Caledonia. Blooms of Trichodesmium are suspected to be a potential source of toxins in the ciguatera food chain and were previously reported to contain several types of paralyzing toxins. The toxicity of water-soluble extracts of Trichodesmium spp. were analyzed by mouse bioassay and Neuroblastoma assay and their toxic compounds characterized using liquid chromatography coupled with tandem mass spectrometry techniques. Here, we report the first identification of palytoxin and one of its derivatives, 42-hydroxy-palytoxin, in field samples of Trichodesmium collected in the New Caledonian lagoon. The possible role played by Trichodesmium blooms in the development of clupeotoxism, this human intoxication following the ingestion of plankton-eating fish and classically associated with Ostreopsis blooms, is also discussed.
Modeling Self-Assembly Across Scales: The Unifying Perspective of Smart Minimal Particles
Authors: Mastrangeli Massimo , Mermoud Grégory , Martinoli Alcherio
Published: April 2011

A wealth of current research in microengineering aims at fabricating devices of increasing complexity, notably by (self-)assembling elementary components into heterogeneous functional systems. At the same time, a large body of robotic research called swarm robotics is concerned with the design and the control of large ensembles of robots of decreasing size and complexity. This paper describes the asymptotic convergence of micro/nano electromechanical systems (M/NEMS) on one side, and swarm robotic systems on the other, toward a unifying class of systems, which we denote Smart Minimal Particles (SMPs). We deﬁne SMPs as mobile, purely reactive and physically embodied agents that compensate for their limited on-board capabilities using speciﬁcally engineered reactivity to external physical stimuli, including local energy and information scavenging. In trading off internal resources for simplicity and robustness, SMPs are still able to collectively perform non-trivial, spatio-temporally coordinated and highly scalable operations such as aggregation and self-assembly (SA). We outline the opposite converging tendencies, namely M/NEMS smarting and robotic minimalism, by reviewing each field’s literature with speciﬁc focus on self-assembling systems. Our main claim is that the SMPs can be used to develop a unifying technological and methodological framework that bridges the gap between passive M/NEMS and active, centimeter-sized robots. By proposing this unifying perspective, we hypothesize a continuum in both complexity and length scale between these two extremes. We illustrate the beneﬁts of possible cross-fertilizations among these originally separate domains, with speciﬁc emphasis on the modeling of collective dynamics. Particularly, we argue that while most of the theoretical studies on M/NEMS SA dynamics belong so far to one of only two main frameworks—based on analytical master equations and on numerical agent-based simulations, respectively—alternative models developed in swarm robotics could be amenable to the task, and thereby provide important novel insights.
Cytotoxic Metabolites from the Soil-Derived Fungus Exophiala Pisciphila
Authors: Wang Cui-Cui , Liu Hai-Zhou , Liu Ming , Zhang Yu-Yan , Li Tian-Tian , Lin Xiu-Kun
Published: April 2011

A new polyketide compound 1 and a new naturally occurring chromone derivative 2, along with two known indole alkaloids 3–4 were characterized from the ethyl acetate extract of a soil-derived fungal strain, Exophiala pisciphila PHF-9. The structures of compounds 1–4 were established by detailed spectroscopic analysis and comparison with literature data. The absolute configuration of 1 was determined by a modified Mosher’s method. Compound 1 exhibited moderate cytotoxicity against A-549, Hela, PANC-28 and BEL-7402 cell lines.
Effects of Panax ginseng on Tumor Necrosis Factor-α-Mediated Inflammation: A Mini-Review
Authors: Lee Davy CW , Lau Allan SY
Published: April 2011

Panax ginseng is one of the most commonly used Chinese medicines in China, Asia and Western countries. The beneficial effects of ginseng have been attributed to the biological activities of its constituents, the ginsenosides. In this review, we summarize recent publications on the anti-inflammatory effects of ginseng extracts and ginsenosides on cellular responses triggered by different inducers including endotoxin, tumor necrosis factor-alpha (TNF-α), interferon-gamma and other stimuli. Proinflammatory cytokines, chemokines, adhesion molecules and mediators of inflammation including inducible nitric oxide synthase, cyclooxygenase-2 and nitric oxide orchestrate the inflammatory response. Ginseng extracts and ginsenosides including Rb1, Rd, Rg1, Rg3, Rh1, Rh2, Rh3 and Rp1 have been reported to have anti-inflammatory properties in different studies related to inflammation. Ginsenosides inhibit different inducers-activated signaling protein kinases and transcription factor nuclear factor-kappaB leading to decreases in the production of cytokines and mediators of inflammation. The therapeutic potential of ginseng on TNF-α-mediated inflammatory diseases is also discussed. Taken together, this summary provides evidences for the anti-inflammatory effects of ginseng extracts and ginsenosides as well as the underlying mechanisms of their effects on inflammatory diseases.
General Pathway for a Convenient One-Pot Synthesis of Trifluoromethyl-Containing 2-amino-7-alkyl(aryl/heteroaryl)-1,8-naphthyridines and Fused Cycloalkane Analogues
Authors: Bonacorso Helio G. , Andrighetto Rosália , Krüger Nícolas , Zanatta Nilo , Martins Marcos A. P.
Published: April 2011

A convenient and general method for the synthesis in 26–73% yields of a new series of 7-alkyl(aryl/heteroaryl)-2-amino-5-trifluoromethyl-1,8-naphthyridines from direct cyclocondensation reactions of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF3C(O)CH=C(R1)OR, where R1 = H, Me, Ph, 4-MePh, 4-OMePh, 4-FPh, 4-BrPh, 4-NO2Ph, 2-furyl, 2-thienyl and R = Me, Et] with 2,6-diaminopyridine (2,6-DAP), under mild conditions, is described. Another synthetic route also allowed the synthesis of 2-amino-5-trifluoromethyl-cycloalka[b][1,8]naphthyridines in 33–36% yields, from direct or indirect cyclo-condensation reactions of five-, six- and seven-membered 2-trifluoroacetyl-1-methoxy-cycloalkenes with 2,6-DAP.
Synthesis and Herbicidal Activity of 5-(4-Hydroxybenzyl)-2-Thioxoimidazolidin-4-one Esters
Authors: Han Jintao , Wang Jinmin , Dong Hongbo , Lei Jianping , Wang Mingan , Fang Jianxin
Published: April 2011

A series of novel 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one esters were synthesized under mild conditions by the reaction of 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one and carboxylic acids with DCC and DMAP as the promoters. Their structures were confirmed by 1H-NMR, IR, ESI-MS and elemental analysis. The preliminary bioassy results indicated that some of compounds exhibit good herbicidal activity against Zea mays, Triticum aestivum and Arabidopsis thaliana. The further greenhouse test showed that compounds 6-16 and 6-28 have 60%, 50% and 50% efficacy against Stellaria media, Echinochloa crus-galli and Setaria viridis at 1,000 g/ha, respectively.
Occurrence and Estimation of trans-Resveratrol in One-Year-Old Canes from Seven Major Chinese Grape Producing Regions
Authors: Zhang Ang , Fang Yulin , Li Xuan , Meng Jiangfei , Wang Hua , Li Hua , Zhang Zhenwen , Guo Zhijun
Published: April 2011

The concentration of trans-resveratrol in 165 grape cane samples from three major grape production regions and four large distribution centers of Chinese wild Vitis species were determined by reversed-phase high-performance liquid chromatography (HPLC). Among the different genotype groups and purpose of uses, cultivars of V. vinifera had much higher amounts of trans-resveratrol than did the cultivars of both V. labrusca or V. labrusca and V. vinifera hybrids, and within the V. vinifera species, significantly higher amounts of trans-resveratrol were found in wine grapes compared to table ones. No significant differences were observed between V. labrusca and its hybrids from crosses with V. vinifera, and between red cultivars and white ones (P < 0.05 or P < 0.01). The contents of trans-resveratrol, as a normal constituent occurring in grape canes, in Chinese wild species of V. amurensis, V. pentagona, and V. davidii from their native habitats were also relatively high.