bluuebunny/crossref_metadata_2025 huggingface dataset:
Zona pellucida from fertilised human oocytes induces a voltage-dependent calcium influx and the acrosome reaction in spermatozoa, but cannot be penetrated by sperm
Authors: Patrat Catherine , Auer Jana , Fauque Patricia , Leandri Roger L , Jouannet Pierre , Serres Catherine
Published: December 2006

Background

The functions of three zona glycoproteins, ZP1, ZP2 and ZP3 during the sperm-zona pellucida (ZP) interaction are now well established in mice. The expression of an additional zona glycoprotein, ZPB/4, in humans, led us to reconsider the classical mouse model of gamete interaction. We investigated the various functions of human ZP (hZP) during the interaction of spermatozoa with fertilised and unfertilised oocytes.

Results

The hZP of fertilised oocytes retained their ability to bind sperm (albeit less strongly than that from unfertilised oocytes), to induce an intraspermatic calcium influx through voltage-dependent channels similar to that observed with hZP from unfertilised oocytes and to promote the acrosome reaction at a rate similar to that induced by the ZP of unfertilised oocytes (61.6 ± 6.2% vs60.7 ± 9.1% respectively). Conversely, the rate of hZP penetrated by sperm was much lower for fertilised than for unfertilised oocytes (19% vs 57% respectively, p < 0.01). We investigated the status of ZP2 in the oocytes used in the functional tests, and demonstrated that sperm binding and acrosome reaction induction, but not ZP penetration, occurred whether or not ZP2 was cleaved.

Conclusion

The change in ZP function induced by fertilisation could be different in human and mouse species. Our results suggest a zona blocking to polyspermy based at the sperm penetration level in humans.
Practice makes perfect: the neural substrates of tactile discrimination by Mah-Jong experts include the primary visual cortex
Authors: Saito Daisuke N , Okada Tomohisa , Honda Manabu , Yonekura Yoshiharu , Sadato Norihiro
Published: December 2006

Background

It has yet to be determined whether visual-tactile cross-modal plasticity due to visual deprivation, particularly in the primary visual cortex (V1), is solely due to visual deprivation or if it is a result of long-term tactile training. Here we conducted an fMRI study with normally-sighted participants who had undergone long-term training on the tactile shape discrimination of the two dimensional (2D) shapes on Mah-Jong tiles (Mah-Jong experts). Eight Mah-Jong experts and twelve healthy volunteers who were naïve to Mah-Jong performed a tactile shape matching task using Mah-Jong tiles with no visual input. Furthermore, seven out of eight experts performed a tactile shape matching task with unfamiliar 2D Braille characters.

Results

When participants performed tactile discrimination of Mah-Jong tiles, the left lateral occipital cortex (LO) and V1 were activated in the well-trained subjects. In the naïve subjects, the LO was activated but V1 was not activated. Both the LO and V1 of the well-trained subjects were activated during Braille tactile discrimination tasks.

Conclusion

The activation of V1 in subjects trained in tactile discrimination may represent altered cross-modal responses as a result of long-term training.
Wild-type huntingtin ameliorates striatal neuronal atrophy but does not prevent other abnormalities in the YAC128 mouse model of Huntington disease
Authors: Van Raamsdonk Jeremy M , Pearson Jacqueline , Murphy Zoe , Hayden Michael R , Leavitt Blair R
Published: December 2006

Background

Huntington disease (HD) is an adult onset neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin (htt) protein. Htt function is essential for embryonic survival as well as normal function during the postnatal period. In addition to having roles in transcription and transport, recent evidence demonstrates that wild-type htt is neuroprotective in vivo. To determine whether treatment with wild-type htt would be beneficial in HD, we crossed the YAC128 mouse model of HD with mice that over-express wild-type htt (YAC18 mice) to generate YAC128 mice that over-express wild-type htt (YAC18/128 mice).

Results

YAC18/128 mice were found to express mutant htt at the same level as YAC128 mice and wild-type htt at the same level as YAC18 mice. YAC18/128 mice show no significant behavioural improvement compared to YAC128 mice in the rotarod test of motor coordination or in an automated open field test. In the brain, YAC18/128 mice show no significant improvement in striatal volume, striatal neuronal numbers or striatal DARPP-32 expression compared to YAC128 mice. In contrast, striatal neuronal cross-sectional area showed significant improvement in YAC18/128 mice compared to YAC128 mice.

Conclusion

While the over-expression of wild-type htt results in a mild improvement in striatal neuropathology in YAC128 mice, our findings suggest that treatment with wild-type htt may not be sufficient to ameliorate the symptoms of HD in this model.
Correlations between subjective treatment responses and plantar pressure parameters of metatarsal pad treatment in metatarsalgia patients: a prospective study
Authors: Kang Jiunn-Horng , Chen Min-Der , Chen Shih-Ching , Hsi Wei-Li
Published: December 2006

Background

Metatarsalgia is related to repetitive high-pressure loading under the metatarsal head (MH) that causes pain. The high pressure under the MH can be reduced by adequately applying metatarsal pads (MPs). Plantar pressure measurements may provide a method to objectively evaluate pressure loading under the MH. However, it is still unclear if the decrease in plantar pressure under the MH after MP treatment is associated with subjective improvement. This study aims to explore the correlations between subjective pain improvement and outcome rating, and the plantar pressure parameters in metatarsalgia patients treated using MPs.

Methods

Thirteen patients (a total of 18 feet) with secondary metatarsalgia were included in this study. Teardrop-shaped MPs made of polyurethane foam were applied just proximal to the second MH by an experienced physiatrist. Insole plantar pressure was measured under the second MH before and after MP application. Visual analog scale (VAS) scores of pain were obtained from all subjects before and after 2 weeks of MP treatment. The subjects rated using four-point subjective outcome scales. The Wilcoxon signed-rank test was used to analyze the difference between the plantar pressure parameters and VAS scores before and after treatment. The Kruskal-Wallis test was applied to compare the plantar pressure parameters in each outcome group. Pearson's correlation was applied to analyze the correlation between the changes in plantar pressure parameters and VAS scores. Statistical significance was set as p < 0.05.

Results

MP application decreased the maximal peak pressure (MPP) and pressure-time integral (PTI) under the second MH and also statistically improved subjective pain scores. However, neither the pre-treatment values of the MPP and PTI shift in the position of the MPP after treatment, nor the age, gender and body mass index (BMI) of the subjects were statistically correlated with subjective improvement. Declines in the PTI and MPP values after MP application were statistically correlated with the improvement in VAS scores (r = 0.77, R
2 = 0.59, p < 0.001; r = 0.60, R
2 = 0.36, p = 0.009).

Conclusion

We found that the successful decline in the PTI and MPP under the second MH after MP application was correlated to subjective pain improvement. This study provides a strategy for the further design and application of MPs for metatarsalgia treatment.
Are Asians comfortable with discussing death in health valuation studies? A study in multi-ethnic Singapore
Authors: Wee Hwee-Lin , Li Shu-Chuen , Xie Feng , Zhang Xu-Hao , Luo Nan , Cheung Yin-Bun , Machin David , Fong Kok-Yong , Thumboo Julian
Published: December 2006

Background

To characterize ease in discussing death (EID) and its influence on health valuation in a multi-ethnic Asian population and to determine the acceptability of various descriptors of death and "pits"/"all-worst" in health valuation.

Methods

In-depth interviews (English or mother-tongue) among adult Chinese, Malay and Indian Singaporeans selected to represent both genders and a wide range of ages/educational levels. Subjects rated using 0–10 visual analogue scales (VAS): (1) EID, (2) acceptability of 8 descriptors for death, and (3) appropriateness of "pits" and "all-worst" as descriptors for the worst possible health state. Subjects also valued 3 health states using VAS followed by time trade-off (TTO). The influence of sociocultural variables on EID and these descriptors was studied using univariable analyses and multiple linear regression (MLR). The influence of EID on VAS/TTO utilities with adjustment for sociocultural variables was assessed using MLR.

Results

Subjects (n = 63, 35% Chinese, 32% Malay, median age 44 years) were generally comfortable with discussing death (median EID: 8.0). Only education significantly influenced EID (p = 0.045). EID correlated weakly with VAS/TTO scores (range: VAS: -0.23 to 0.07; TTO: -0.14 to 0.11). All subjects felt "passed away", "departed" and "deceased" were most acceptable (median acceptability: 8.0) while "sudden death" and "immediate death" were least acceptable (median acceptability: 5.0). Subjects clearly preferred "all-worst" to "pits" (63% vs. 19%, p < 0.001).

Conclusion

Singaporeans were generally comfortable with discussing death and had clear preferences for several descriptors of death and for "all-worst". EID is unlikely to influence health preference measurement in health valuation studies.
The strength of the HIV-1 3' splice sites affects Rev function
Authors: Kammler Susanne , Otte Marianne , Hauber Ilona , Kjems Jørgen , Hauber Joachim , Schaal Heiner
Published: December 2006

Background

The HIV-1 Rev protein is a key component in the early to late switch in HIV-1 splicing from early intronless (e.g. tat, rev) to late intron-containing Rev-dependent (e.g. gag, vif, env) transcripts. Previous results suggested that cis-acting sequences and inefficient 5' and 3' splice sites are a prerequisite for Rev function. However, we and other groups have shown that two of the HIV-1 5' splice sites, D1 and D4, are efficiently used in vitro and in vivo. Here, we focus on the efficiency of the HIV-1 3' splice sites taking into consideration to what extent their intrinsic efficiencies are modulated by their downstream cis-acting exonic sequences. Furthermore, we delineate their role in RNA stabilization and Rev function.

Results

In the presence of an efficient upstream 5' splice site the integrity of the 3' splice site is not essential for Rev function whereas an efficient 3' splice site impairs Rev function. The detrimental effect of a strong 3' splice site on the amount of Rev-dependent intron-containing HIV-1 glycoprotein coding (env) mRNA is not compensatable by weakening the strength of the upstream 5' splice site. Swapping the HIV-1 3' splice sites in an RRE-containing minigene, we found a 3' splice site usage which was variably dependent on the presence of the usual downstream exonic sequence. The most evident activation of 3' splice site usage by its usual downstream exonic sequence was observed for 3' splice site A1 which was turned from an intrinsic very weak 3' splice site into the most active 3' splice site, even abolishing Rev activity. Performing pull-down experiments with nuclear extracts of HeLa cells we identified a novel ASF/SF2-dependent exonic splicing enhancer (ESE) within HIV-1 exon 2 consisting of a heptameric sequence motif occurring twice (M1 and M2) within this short non-coding leader exon. Single point mutation of M1 within an infectious molecular clone is detrimental for HIV-1 exon 2 recognition without affecting Rev-dependent vif expression.

Conclusion

Under the conditions of our assay, the rate limiting step of retroviral splicing, competing with Rev function, seems to be exclusively determined by the functional strength of the 3' splice site. The bipartite ASF/SF2-dependent ESE within HIV-1 exon 2 supports cross-talk between splice site pairs across exon 2 (exon definition) which is incompatible with processing of the intron-containing vif mRNA. We propose that Rev mediates a switch from exon to intron definition necessary for the expression of all intron-containing mRNAs.
Governing therapy choices: Power/Knowledge in the treatment of progressive renal failure
Authors: Holmes Dave , Perron Amélie M , Savoie Marc
Published: December 2006

This article outlines the struggle between the power of the health care professional and the rights of the individual to choose freely a modality of treatment. Nurses are instrumental in assisting patients in making the best decision for a therapy they will have to assume for the rest of their lives. In guiding patients' decision, nurses must take into account these unavoidable contingencies: changes in lifestyle, nutritional restrictions, level of acceptance, compliance issues, ease of training and availability of support/facilities. Ensuring that the patient makes an informed decision is therefore an ongoing challenge for nurses as they are taking part in a delicate balancing act between not directly influencing the patient's decision while making sure the patient is accurately informed.
Obesity and the Metabolic Syndrome
Authors: JAMES W.P.T. , RIGBY N. , LEACH R.
Published: December 2006

Abstract:  The problem of obesity was only accepted by the World Health Organization as of major public health importance in 1997 when the criteria for the specification of the metabolic syndrome were also being sought. Then the risk factor analyses of the determinants of global ill health at the start of the millennium showed that an excessive body mass index (BMI) above the optimum of 21 was one of the top 10 contributors. No analyses could be related to abdominal obesity because of the absence of systematic representative surveys of waist circumferences but the ill health attributable to excess weight included the risk factors specified in the metabolic syndrome and showed that the co‐morbidities in Asia were far greater than those predicted from simply an excess weight. The recent proposed definition of the metabolic syndrome includes these different criteria specified on an ethnic basis but there is now a need to recognize that abdominal obesity is more common on the developing world and linked to childhood stunting and early deprivation. The importance of intrauterine and postnatal epigenetic and altered organ function needs to be recognized. Thus the co‐morbidities associated with weight gain and the development of the metabolic syndrome dominate in the developing world where the majority of the population is proving more susceptible to the effects of weight gain than Caucasians now living in affluent societies. This therefore presents a major challenge in both research and public policy terms.
Stress in Women
Authors: DIAMANTI‐KANDARAKIS EVANTHIA , ECONOMOU FRANGISKOS
Published: December 2006

Abstract:  Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome that is characterized from oligo‐ or anovulation, clinical and/or biochemical signs of hyperandrogenism, and polycystic ovaries. Clinical expression is determined by genetic as well as environmental factors. Women with PCOS are a specific group of women which have several aspects of metabolic syndrome (MBS). Concomitantly MBS could be part of metabolic abnormalities present in PCOS. Stress has been linked to aggravate the metabolic abnormalities present in MBS. An interaction seems to exist between stress, environmental, as well as genetic factors, starting from the prenatal age and continuing to the adult life. This results in specific endocrinological and metabolic disorders which are shared by women with PCOS and women with MBS.
The Hypothalamic‐Pituitary‐Adrenal Axis Activity in Obesity and the Metabolic Syndrome
Authors: PASQUALI RENATO , VICENNATI VALENTINA , CACCIARI MAURO , PAGOTTO UBERTO
Published: December 2006

Abstract:  A hypothetical role of glucocorticoids in human obesity has been suggested since the abdominal obesity phenotype and syndromes of endogenous or exogenous hypercortisolism share several clinical, metabolic, and cardiovascular similarities. An emerging body of evidence indicates that both neuroendocrine dysregulation of the hypothalamic‐pituitary‐adrenal (HPA) axis as well as peripheral alterations of cortisol metabolism may play a role in the pathophysiology of abdominal obesity. Major alterations of the HPA axis in vivo may be identified in different ways. They include evaluation of hormone concentrations: (a) in basal conditions, in blood, urine, or saliva samples; (b) during dynamic studies following stimulation with different neuropeptides or psychological stress challenges, or suppression with inhibiting agents of the HPA axis at different levels; and (c) after mixed meals or meals containing different nutrient compositions. In addition, alteration of peripheral cortisol metabolism can be detected by direct measurement of cortisol metabolites in urine, although this is a matter of more complex investigation. Alterations of the HPA axis in abdominal obesity are associated with insulin resistance, which suggests a direct responsibility of these hormonal alterations in the susceptibility of affected patients to develop both metabolic and cardiovascular diseases. According to available data, no single marker probably has the power to detect subtle alterations of the HPA axis in conditions, such as the abdominal obesity and the metabolic syndrome. On the contrary, they indicate the need for multiple parameters. At present, evaluation of urinary free cortisol, particularly during the night‐time, and salivary‐free cortisol appear to be promising for these purposes, whereas dynamic tests should be reserved for specific clinical settings, involving well‐characterized patients.
A Brief Update of Glucocorticoid Receptor Variants and Obesity Risk
Authors: ROSMOND ROLAND , RADULOVIC VLADIMIR , HOLM GÖRAN
Published: December 2006

Abstract:  Excess body fat, obesity, is one of the most common disorders in clinical practice. Obese individuals are at increased risk for physical ailments, such as type 2 diabetes, coronary heart disease, hypertension, and several types of cancer. The location of the body fat is a major determinant of the degree of excess morbidity and mortality due to obesity. More specifically, the amount of subcutaneous truncal or abdominal fat, and the amount of visceral fat located in the abdominal cavity independently predicts obesity‐related adverse health outcomes. The obesity gene map shows putative loci on all chromosomes except Y. More than 300 genes, markers, and chromosomal regions have been associated or linked with human obesity phenotypes. These genes can be divided into two broad categories: (a) rare gene variants that have a strong influence, and (b) common gene variants that have a weaker influence on obesity phenotypes. Studies in humans have suggested a positive association between obesity, hypertension, and insulin resistance, with alleles at the glucocorticoid receptor gene. In this article, we will estimate the risk by which such gene polymorphism mediates a role in obesity.
Nutrition and Inflammatory Load
Authors: KONTOGIANNI M.D. , ZAMPELAS A. , TSIGOS C.
Published: December 2006

Abstract:  Chronic inflammation has been suggested to play an important role in metabolic diseases, such as atherothrombosis and type 2 diabetes. A lot of research has focused on the immunomodulatory effects of several nutrients, such as fatty acids, antioxidants, carbohydrates, specific amino acids, micronutrients, and alcohol, which play a crucial role in the maintenance of an “optimal” immune response. In addition, specific dietary patterns, such as the Mediterranean diet, are evolving as protective against cardiovascular disease, because of their anti‐inflammatory properties. In this article, the existing data concerning the nutrients' pro‐ and anti‐inflammatory properties are presented, as well as dietary patterns that could protect from chronic inflammation and its metabolic and atherothrombotic complications.
Targeting Components of the Stress System as Potential Therapies for the Metabolic Syndrome
Authors: YUMUK VOLKAN D.
Published: December 2006

Abstract:  The three peroxisome‐proliferator‐activated receptor (PPAR) subtypes PPAR‐α, PPAR‐γ, and PPAR‐δ are ligand‐activated transcription factors of the nuclear receptor family. PPARs form obligate heterodimers with the retinoid X receptor, which bind to peroxisome‐proliferator‐response elements (PPREs). PPAR‐α is expressed mainly in liver, brown fat, kidney, heart, and skeletal muscle; PPAR‐γ in intestine and adipose tissue; PPAR‐α and PPAR‐γ are both expressed in vascular endothelium, smooth muscle cells, macrophages, and foam cells; PPAR‐δ in skeletal muscle, human embryonic kidney, intestine, heart, adipose tissue, developing brain, and keratinocytes. Intense interest in the development of drugs with new mechanisms of action for the metabolic syndrome has focused attention on nuclear receptors, such as PPARs that function as regulators of energy homeostasis. Agonists of PPAR‐α and PPAR‐γ are currently used to treat diabetic dyslipidemia and type 2 diabetes. Dual PPAR‐α/γ agonists and PPAR‐α/γ/δ pan‐agonists are under investigation for treatment of cardiovascular disease and the metabolic syndrome. Selective PPAR modulators (SPPARMs) are PPAR ligands that possess desirable efficacy and improved tolerance. Efforts are being made to identify novel partial agonists or antagonists for PPAR‐γ in order to combine their antidiabetic and antiobesity effects. Glucocorticoids are major mediators of the stress response and could be the link between stress and PPAR activator signaling and thus may affect the downstream metabolic pathways involved in fuel homeostasis.
The Endocannabinoid System as a Target for the Treatment of Visceral Obesity and Metabolic Syndrome
Authors: KYROU IOANNIS , VALSAMAKIS GEORGE , TSIGOS CONSTANTINE
Published: December 2006

Abstract: The endogenous cannabinoid system is a novel, remarkably elaborate physiological signaling system, comprising the recently identified endogenous cannabinoid ligands, their corresponding selective receptors, and the machinery of proteins and enzymes that is involved in their biosynthesis, release, transport, and degradation. This system extends widely in both the central nervous system (CNS) and the periphery and exhibits a variety of actions implicated in vital functions (e.g., behavioral, antinociceptive, neuroprotective, immunosuppressive, cardiovascular, and metabolic). Particular interest has been focused on the apparent participation of endocannabinoids in metabolic homeostasis by modulating the activity of CNS circuits that control food intake and energy expenditure, the neuroendocrine response of the stress system, and the metabolic functions of crucial peripheral tissues, such as the adipose tissue, the gastrointestinal tract, the liver, and the skeletal muscles. These effects are predominantly CB1receptor mediated and, thus, selective antagonists of this receptor subtype are being vigorously investigated as potential therapeutic agents for the treatment of various metabolic derangements (e.g., obesity, insulin resistance, dyslipidemia, and metabolic syndrome). The first selective CB1receptor antagonist, rimonabant, has already successfully completed phase III clinical trials as adjunctive obesity treatment, with significant improvements in several associated metabolic and cardiovascular risk factors that led to the recent approval of its clinical use by the Food and Drug Administration.
Fetal Origins of Stress‐Related Adult Disease
Authors: KAJANTIE EERO
Published: December 2006

Abstract:  During the past decade, a considerable body of evidence has emerged showing that circumstances during the fetal period may have lifelong programming effects on different body functions with a considerable impact on disease susceptibility
. The purpose of this article is to provide a synopsis of these findings and their role in explaining the development of stress‐related adult disease. In the context of Per Björntorp memorial symposium, stress‐related disease will be interpreted broadly, including cardiovascular disease and components of the metabolic syndrome, for which the evidence of fetal origins is most abundant. It has however become evident that early‐life programming has a much broader potential effect on an individual's health. For example, perinatal variables, such as low birth weight, have been associated with increased prevalence of depressive symptoms. Mechanistic studies in animals and humans have shown that lifelong programming of the hypothalamic‐pituitary‐adrenal axis (HPAA) function by fetal life conditions is likely to be a key factor in mediating associations with these disorders, which frequently are characterized by HPAA overactivity. Preliminary observations suggest a similar important role for early‐life programming of sympathoadrenal function. Reduced HPAA activity is characteristic of a number of stress‐related disorders, including posttraumatic stress disorder; chronic pain; fatigue; and atypical, melancholic depression. It is therefore highly plausible that susceptibility to these disorders originates in a similar manner during early life, although direct evidence is to a great deal lacking. Important targets for future research include distinction between the effects of different pregnancy conditions, such as maternal malnutrition, preeclampsia, and maternal infection, which may have dissimilar late‐life consequences. This will be a crucial step when the associations that are currently emerging will be translated into disease prevention.
Birth Weight, Stress, and the Metabolic Syndrome in Adult Life
Authors: PHILLIPS DAVID I.W. , JONES ALEXANDER , GOULDEN PETER A.
Published: December 2006

Abstract:  There is now widespread agreement that small size at birth is associated with an increased risk of the metabolic syndrome (glucose intolerance, high blood pressure, and dyslipidemia) and related pathologies, including cardiovascular disease in later life. Evidence is emerging that suggests that programming of hormonal systems in response to an adverse fetal environment may be one of the mechanisms underlying these long‐term consequences of growth restriction in early life. In particular, alterations in neuroendocrine responses to stress may be important. Recent research suggests that increased adrenocortical and sympathoadrenal responses are associated with small size at birth. Epidemiological studies show that such physiological alterations in these neuroendocrine systems may have potent effects on risk of cardiovascular disease through their influence on risk factors, such as plasma glucose and lipid concentrations and blood pressure.
Laser nanochemistry
Authors: Masuhara Hiroshi , Asahi Tsuyoshi , Hosokawa Yoichiroh
Published: December 2006

Various time- and space-resolved spectroscopies have been developed and applied to thin films and nanoparticles. Dynamic reflection spectroscopies of total internal, diffuse, and regular reflection modes analyze photophysical and photochemical processes at the interface/surface layers with thicknesses of a few tens to a few hundreds of nm and of optically scattering materials. The excited singlet, triplet, and ionic states are identified, and intersystem crossing, isomerization, electron transfer and recombination, and photothermal conversion due to excited-state annihilation are analyzed, just as by transmittance mode spectroscopy. Fluorescence and Rayleigh light-scattering spectroscopies are developed for elucidating excited-state dynamics of single nanoparticles. The optical properties are related to their size, shape, internal structure, and environmental conditions. We prove that organic molecular materials show novel nanometer-size effects due to structural confinement. The high-intensity laser excitation induces ablation whose dynamics and mechanism are considered on the basis of time-resolved spectroscopy and imaging. For nanosecond and femtosecond ablation, we propose cyclic multiphotonic absorption and photomechanical mechanisms, respectively, while purely photochemical ablation was confirmed. Ablation studies have opened a new research approach toward expansion and contraction dynamics of polymer films, nanoparticle preparation, crystal growth control, crystallization in saturated solution, and others.
Efficient radical addition of tertiary amines to alkenes using photochemical electron transfer
Authors: Hoffmann Norbert , Bertrand Samuel , Marinković Siniša , Pesch Jens
Published: December 2006

An efficient photoinduced radical addition of tertiary amine, mainly cyclic derivatives, to electron-deficient alkenes was developed. The reaction was applied to the asymmetric synthesis of the pyrrolizidine alkaloids laburnine and isoretronecanol. The method was then optimized for the addition of a larger variety of tertiary amines, in particular acyclic ones. Radical tandem addition cyclization reactions with unsaturated tertiary amines have also been investigated. A detailed mechanistic study using isotopic labeling enabled the optimization of a corresponding reaction with N,N-dialkylaniline derivatives. The origin of the high reaction stereoselectivity achieved with menthyloxyfuranone was elucidated. The radical addition of tertiary amines was also performed with heterogeneous photocatalysis using inorganic semiconductors as sensitizers.
Overall water splitting using (oxy)nitride photocatalysts
Authors: Maeda Kazuhiko , Teramura Kentaro , Saito Nobuo , Inoue Yasunobu , Kobayashi Hisayoshi , Domen Kazunari
Published: December 2006

Oxynitride photocatalysts with d
10 electronic configuration are presented as effective non-oxide catalysts for overall water splitting. Germanium nitride (β-Ge3N4) having a band gap of 3.8-3.9 eV modified with RuO2 nanoparticles as a cocatalyst is shown to achieve stoichiometric decomposition of H2O into H2 and O2 under UV irradiation (λ > 200 nm). A novel solid solution of GaN and ZnO, (Ga1-x
Zn
x
)(N1-x
O
x
), with a band gap of 2.4-2.8 eV (depending on composition) achieves overall water splitting under visible light (λ > 400 nm) when loaded with an appropriate cocatalyst. The narrower band gap of the solid solution is attributed to the bonding between Zn and N atoms at the top of the valence band. The photocatalytic activity of (Ga1-x
Zn
x
)(N1-x
O
x
) for overall water splitting is strongly dependent on both the cocatalyst and the crystallinity and composition of the material. The quantum efficiency of (Ga1-x
Zn
x
)(N1-x
O
x
) with Rh and Cr mixed-oxide nanoparticles is 2-3 % at 420-440 nm, which is the highest reported efficiency for overall water splitting in the visible-light region.
Oxidative damage to DNA: Inhibition of guanine damage
Authors: Kanvah Sriram , Schuster Gary B.
Published: December 2006

One-electron oxidation of DNA results in chemical damage to nucleobases, particularly guanine in multiple G sequences. Oxidation may be triggered by numerous events, including photosensitization. We describe studies of photoinduced oxidations of DNA triggered by irradiation of covalently linked anthraquinone derivatives under various conditions that affect the global structure of the DNA. These structural changes have subtle effects on the result of the one-electron oxidation.
Highly selective fluorescent nucleobases for designing base-discriminating fluorescent probes
Authors: Saito Isao , Saito Yoshio , Hanawa Kazuo , Hayashi Keigo , Motegi Kaori , Bag Subhendu Sekhar , Dohno Chikara , Ichiba Tomohisa , Tainaka Kazuki , Okamoto Akimitsu
Published: December 2006

There is increasing interest in single nucleotide polymorphism (SNP) typing since they can be used as markers to identify the genes that underlie complex diseases and to realize the full potential of pharmacogenomics in analyzing variable response to drugs. Among the different methodologies for SNP genotyping, the homogenous assay is more amenable than the heterogeneous one.

In this article, we will describe some of our most recently developed novel base-discriminating fluorescent (BDF) nucleosides useful for homogenous SNP typing. Our novel concept led to the investigation of a new type of pyrene-labeled BDF nucleosides PyU, PyC, 8pyA, and MePydA, which emitted strong fluorescence only when the bases opposite the BDF bases are A, G, T, and C, respectively. The DNA probes containing four different BDF bases enabled us to distinguish single-base alterations by simply mixing with a sample solution of target DNA. An example of SNP typing of c-Ha-ras SNP sequence has also been demonstrated. Detection of base insertion in insertion/deletion (indel) polymorphisms using pyrene excimer fluorescent probe has also been explored.
Detection of biomacromolecules with fluorescent light-up probes
Authors: Faulhaber Katja , Granzhan Anton , Ihmels Heiko , Viola Giampietro
Published: December 2006

The emission properties of selected benzo[b]quinolizinium (acridizinium) derivatives in the presence of double-stranded DNA and proteins are presented. Spectrophotometric studies and linear dichroism (LD) spectroscopic experiments reveal that benzo[b]quinolizinium derivatives bind to DNA, mainly by intercalation. In contrast to the 9-aminobenzo[b]quinolizinium, which exhibits a moderate emission quantum yield in water, the 6-aminobenzo[b]quinolizinium ion as well as N-phenyl-9-aminobenzo[b]quinolizinium derivatives are almost nonfluorescent. The low intrinsic fluorescence quantum yields of the latter compounds are caused by conformational changes in the excited state, as shown by a linear double-logarithmic plot of the emission quantum yield vs. the solvent viscosity. Most notably, the fluorescence intensities of these dyes increase significantly by a factor of 10 to 50 upon addition of double-stranded DNA or proteins such as human serum albumin (HSA) or chicken egg albumin (CEA). Thus, these compounds exhibit ideal properties to be used as DNA- or protein-sensitive light-up probes.
Self-assembling and light-harvesting properties of fluorescent linear condensed aromatic gelators
Authors: Desvergne Jean-Pierre , Olive Alexandre G. L. , Sangeetha Neralagatta M. , Reichwagen Jens , Hopf Henning , Del Guerzo André
Published: December 2006

The self-assembling and photophysical properties of soluble fluorescent linear condensed aromatic gelators are reported. The gels formed by 2,3-alkoxy derivatives are constituted of nanofibers weaving a 3-dimensional supramolecular network and imprisoning the solvent. These nanofibers are efficient light-harvesting systems in which complete energy transfer toward a fluorescent acceptor can be achieved at doping levels below 1 mol % of acceptor.
Geometric Indices of Bone Strength Are Associated With Physical Activity and Dietary Calcium Intake in Healthy Older Women
Authors: Nurzenski Michelle K , Briffa N Kathryn , Price Roger I , Khoo Benjamin CC , Devine Amanda , Beck Thomas J , Prince Richard L
Published: December 2006

A population-based study on 1008 postmenopausal women identified that the 24% of women achieving high levels of PA and CI had 3.4–4.4% higher femoral bone strength in axial compression and 1.7–5.2% in bending than those achieving low levels, indicating that lifestyle factors influence bone strength in the proximal femur.

Introduction: Extensive research has shown that increased physical activity (PA) and calcium intake (CI) decrease the rate of bone loss; however, there is little research on how these lifestyle variables affect bone geometry. This study was designed to investigate the effects of modifiable lifestyle variables, habitual PA and dietary CI, on femoral geometry in older women.

Materials and Methods: Femoral geometry, habitual PA, and dietary CI were measured in a population-based sample of 1008 women (median age ± interquartile range, 75 ± 4years) enrolled in a randomized controlled trial (RCT) of calcium supplementation. Baseline PA and CI were assessed by validated questionnaires, and 1-year DXA scans (Hologic 4500A) were analyzed using the hip structural analysis technique. Section modulus (Z), an index of bending strength, cross-sectional area (CSA), an index of axial compression strength, subperiosteal width (SPW), and centroid position, the position of the center of mass, were measured at the femoral neck (NN), intertrochanter (IT), and femoral shaft (FS) sites. These data were divided into tertiles of PA and CI, and the results were compared using analysis of covariance (ANCOVA), with corrections for age, height, weight, and treatment (calcium/placebo).

Results and Conclusions: PA showed a significant dose–response effect on CSA all hip sites (p < 0.03) and Z at the narrow neck and intertrochanter sites (p < 0.02). For CI, there was a dose–response effect for centroid position at the intertrochanter (p = 0.03). These effects were additive, such that the women (n = 240) with PA in excess of 65.5 kcal/day and CI in excess of 1039 mg/day had significantly greater CSA (NN, 4.4%; IT, 4.3%; FS, 3.4%) and Z (NN, 3.9%; IT, 5.2%). These data show a favorable association between PA and aspects of bone structural geometry consistent with better bone strength. Association between CI and bone structure was only evident in 1 of 15 variables tested. However, there was evidence that there may be additive effects, whereby women with high levels of PA and CI in excess of 1039 mg/day had significantly greater CSA (NN, 0.4%; FS, 2.1%) and Z (IT, 3.0%) than women with high PA but low CI. These data show that current public health guidelines for PA and dietary CI are not inappropriate where bone structure is the health component of interest.
Low-Density Lipoprotein Receptor–Related Protein 5 (LRP5) Gene Polymorphisms Are Associated With Bone Mass in Both Chinese and Whites
Authors: Xiong Dong-Hai , Lei Shu-Feng , Yang Fang , Wang Liang , Peng Yu-Mei , Wang Wei , Recker Robert R , Deng Hong-Wen
Published: December 2006

In this study, the associations of novel LRP5 variants with BMD variation were detected and some replicated in the two ethnic groups of Chinese and white origins, respectively. These data support the concept that LRP5 variation can contribute to minor and major variation in bone structure.

Introduction: Mutations in the low-density lipoprotein receptor-related protein 5 (LRP5) gene have been shown to cause both high and low bone mass. However, it is still controversial whether LRP5 is associated with normal BMD variation. This study explored the association of LRP5 with BMD phenotypes at three clinically important skeletal sites—the spine, hip, and ultradistal radius (UD)—in two independent populations of Chinese and white ethnicities, respectively.

Materials and Methods: The Chinese sample consisted of 733 unrelated subjects. The white sample was made up of 1873 subjects from 405 nuclear families. High-density single nucleotide polymorphisms (SNPs) across the whole LRP5 gene were genotyped and analyzed in both samples.

Results: Linkage disequilibrium (LD) analyses showed that the haplotype structures of LRP5 between Chinese and whites were in good agreement. Association tests showed that polymorphisms in block 5 spanning intron 7 to intron 19 of LRP5 significantly associated with spine BMD variation in both samples. Particularly, the significant association of SNP rs491347 in intron 7 with spine BMD in the Chinese sample (p = 0.002) was replicated in whites, even after adjusting for multiple testing (p = 0.005). Its strongly associated SNP rs1784235 could cause the loss of an estrogen receptor α (ERα) binding site in LRP5, which could partially explain the above replicated association. However, we did not observe any significant replication with BMD variation at the hip and UD. After accounting for multiple testing, associations with BMD variation at these two sites were mainly found in Chinese. Sex-stratified analyses further revealed that the LRP5 associations with BMD in Chinese and whites were driven by male and female subjects, respectively.

Conclusions: Our work supported LRP5 genetic variants as possible susceptibility factors for osteoporosis and fractures in humans. Especially, the SNP rs491347 and its strongly associated SNPs (e.g., rs1784235) could be important to human osteoporosis phenotypes.
Calcination of Marls to Produce Roman Cement
Authors: Hughes DC , Jaglin D , Kozlowski R , Mayr N , Mucha D , Weber J
Published: December 2006

Marls were identified from a range of European sources and assessed for their Cementation Index, as proposed by Eckel. Two were selected for calcination in a laboratory kiln; one from Folwark in Poland (CI 1.75) and one from Lillienfeld in Austria (CI 2.03). Analysis of historical documents, while not revealing precise kiln conditions, does suggest that they were such as not to yield complete decarbonation of the calcite. Consequently, a series of calcinations was undertaken in which the peak temperature control of the kiln was set in the range 730°C to 1100°C, with residence times in the range 150 to 1250 min. The airflow through the kiln was sufficient to maintain a minimum oxygen content of at least 12 %. The resulting clinker was ground to comply with the 19th century Austrian Norme. Pastes were produced at w/c = 0.65 and assessed for setting time and strength development (6 h to 1 year). Both parameters were highly dependent upon calcination conditions with both “low” and “high” calcinations producing slower setting and slower strength development than intermediate conditions. Two strength development profiles were identified; one being the expected continuous increase of strength, albeit with a declining rate of increase with time, while the other showed a three-step sequence of high initial strength, a dormant period which could last for many weeks and a final increase in strength to an age of one year. The cements were compared using X-ray diffraction (XRD). Considerable variation in the composition was noted and related to the calcination conditions. Of particular interest is the formation of both α'-belite and β-belite under differing calcination conditions. Clinker particles were also compared using the SEM in back-scattered electron imaging mode and the development of morphology observed.
Nova espécie de Phalotris, redescrição de P. tricolor e osteologia craniana (Serpentes, Elapomorphinae)
Authors: Lema Thales de , D'Agostini Fernanda Maurer , Cappellari Lize Helena
Published: December 2006

A comparação dos espécimes-tipo de Phalotris tricolor (Duméril, Bibron & Duméril, 1854) e Elapomorphus punctatus Lema, 1979 demonstrou que ambos nomes se referem ao mesmo táxon; o nome P. tricolor, empregado até o momento, é um complexo de P. tricolor e uma espécie ainda não conhecida, descrita aqui como P. matogrossensis sp. nov. distribuída do sudoeste do Brasil às áreas adjacentes no Paraguai, em formações de Cerrado. A nova espécie difere de P. tricolor principalmente por apresentar região inferior da cabeça branca, ao invés de inteiramente preta; colar branco mais longo que o preto; ao invés de curto e com um colar preto muito mais longo; colar preto apenas dorsal, ao invés de atingir os lados do ventre; coloração dorsal de fundo vermelha brilhante e não amarelada ou marrom-avermelhada, com pontos pretos dispersos em séries longitudinais. O crânio e hemipênis das duas espécies não apresentam maiores diferenças. As duas espécies, mais P. mertensi (Hoge, 1955) e P. cuyanus (Cei, 1984), compõem o grupo tricolor e é apresentada uma chave para a identificação das espécies do grupo.
Metanotal gland of the genus Eidmanacris (Grylloidea, Phalangopsidae): taxonomic importance
Authors: Prado Rogilene Aparecida , Fontanetti Carmem S.
Published: December 2006

The present study compares the metanotal gland through scanning electron microscopy in five species of Eidmanacris: E. corumbatai Garcia, 1998, E. alboannulata (Piza, 1960), E. dissimilis Desutter-Grandcolas, 1995, E. larvaeformis (Chopard, 1938) and Eidmanacris sp. The general external configuration of the gland was determined by the presence of two median projections with apical opening and a cluster of bristles just above these projections. Although there is a general pattern for this gland, each species has its own pattern, which can be defined mainly by the arrangement of the bristles and the position of the median projections. Our results suggest the taxonomical importance of these structures, which should be better analyzed when describing species of the genus Eidmanacris. In addition, while observing the reproductive behavior of these species, we concluded that the release of this gland secretion is important for the success of mating.
Espécies novas de Blaptica do Rio Grande do Sul, Brasil (Blattaria, Blaberidae, Blaberinae)
Authors: Lopes Sonia Maria , Oliveira Edivar Heeren de
Published: December 2006

Cinco novas espécies de Blaptica Stål, 1875 do Estado do Rio Grande do Sul, Brasil são descritas e apresentadas ilustrações de Blaptica dubia.
Traditional and transgenic strategies for controlling tomato-infecting begomoviruses
Authors: FREITAS-ASTÚA JULIANA , PURCIFULL DAN E. , POLSTON JANE E. , HIEBERT ERNEST
Published: December 2006

Viruses of to the family Geminiviridae are considered some of the most important pathogens in tropical and subtropical regions of the world. Members of one Geminiviridae genus, Begomovirus, have been causing severe losses, particularly in tomato (Lycopersicon esculentum) production in the Americas and the Caribbean. Several new begomoviruses have been reported in the region and, at least one, Tomato yellow leaf curl virus (TYLCV), has been brought in from the Old World via infected transplants. In addition, the recombination events that are playing an important role in Begomovirus diversity have increased the complexity of their control. This scenario has led to the search for control measures that go beyond traditional host genetic resistance, chemical controls and cultural practices. In this review, besides the recommended classical control measures, transgenic approaches will be discussed, as well as the mechanisms involved in their successful control of viruses.
Expression of resistance in rice hybrids to Pyricularia grisea
Authors: PRABHU ANNE S. , GUIMARÃES ELCIO P. , FILIPPI MARTA C. , ARAUJO LEILA G. , CUTRIM VERIDIANO A.
Published: December 2006

Thirty-nine rice (Oryza sativa) hybrids and their restorers were assessed for vertical resistance to Pyricularia grisea in the rice blast nursery, and in artificial inoculation tests with two pathotypes, under controlled greenhouse conditions. The hybrids were developed from cytoplasmic genetic male sterile lines 046I and IR 58025A, derived from WA cytoplasm. In the rice blast nursery all hybrids showed susceptible reaction varying from 5 to 9. Compatible and incompatible leaf blast reactions of hybrids to two pathotypes, IC-1 and IB-45, were observed in inoculation tests. A majority of the hybrids were resistant when the restorer was resistant. However, seven of the 25 F1 hybrids exhibited susceptible reactions even when one of the parents was resistant to a pathotype. The partial resistance of 11 hybrids and their parents that showed compatible reactions to two pathotypes was analyzed. Differential interaction between isolates and genotypes was observed for partial resistance in relation to both disease severity and lesion number indicating the specific nature of partial resistance.