bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the wild‐type and mutant genes encoding the enzyme kynurenine monooxygenase of the yellow fever mosquito, Aedes aegypti
Authors: Han Q. , Calvo E. , Marinotti O. , Fang J. , Rizzi M. , James A. A. , Li J.
Published: September 2003

Kynurenine 3‐monooxygenase (KMO) catalyses the hydroxylation of kynurenine to 3‐hydroxykynurenine. KMO has a key role in tryptophan catabolism and synthesis of ommochrome pigments in mosquitoes. The gene encoding this enzyme in the yellow fever mosquito, Aedes aegypti, is called kynurenine hydroxylase (kh) and a mutant allele that produces white eyes has been designated khw. A number of cDNA clones representative of wild‐type and mutant genes were isolated. Sequence analyses of the wild‐type and mutant cDNAs revealed a deletion of 162 nucleotides in the mutant gene near the 3′‐end of the deduced coding region. RT‐PCR analyses confirm the transcription of a truncated mRNA in the mutant strain. The in‐frame deletion results in a loss of 54 amino acids, which disrupts a major α‐helix and which probably accounts for the loss of activity of the enzyme. Recombinant Ae. aegypti KMO showed high substrate specificity for kynurenine with optimum activity at 40 °C and pH = 7.5. Kinetic parameters and inhibition of KMO activity by Cl– and pyridoxal‐5‐phosphate were determined.
Involvement of the JNK‐like protein of the Aedes albopictus mosquito cell line, C6/36, in phagocytosis, endocytosis and infection of West Nile virus
Authors: Mizutani T. , Kobayashi M. , Eshita Y. , Shirato K. , Kimura T. , Ako Y. , Miyoshi H. , Takasaki T. , Kurane I. , Kariwa H. , Umemura T. , Takashima I.
Published: September 2003

We recently cloned a c‐Jun amino‐terminal kinase (JNK) sequence from the C6/36 cell line, derived from the mosquito Aedes albopictus. We showed that SP600125, an inhibitor of JNK proteins, inhibits phagocytosis by C6/36 cells, suggesting that the JNK‐like protein regulates phagocytosis. Here, we show that C6/36 cells constitutively express low levels of mRNA encoding the antibacterial peptides, cecropin and defensin, but that these mRNAs were up‐regulated upon stimulation by lipopolysaccharide (LPS). Thus, the C6/36 cells have properties similar to those of mammalian macrophages. To characterize further the functional properties of C6/36 cells, we have assayed the role of the JNK‐like protein in phagocytosis, endocytosis, and viral infection. C6/36 cells phagocytosed bacteria and artificial beads, and this was only slightly up‐regulated following LPS stimulation, suggesting that newly stimulated JNK‐like protein was not necessary for phagocytosis. SP600125 inhibited the acidification of intracellular compartments, including those involved in the endocytic pathway. Pretreatment of C6/36 cells with SP600125 or bafilomycin A1, but not cytochalasin D, inhibited the entry of West Nile virus (WNV), suggesting that WNV is internalized mainly by endocytosis, and that the JNK signalling pathway is important for endocytic entry. These findings indicate that the JNK‐like protein regulates basic physiological functions, including phagocytosis and endocytosis and infection of WNV.
A teratocyte gene from a parasitic wasp that is associated with inhibition of insect growth and development inhibits host protein synthesis
Authors: Dahlman D. L. , Rana R. L. , Schepers E. J. , Schepers T. , DiLuna F. A. , Webb B. A.
Published: September 2003

After parasitization, some wasps induce hosts prematurely to initiate metamorphic development that is then suspended in a postwandering, prepupal state. Following egression of the parasite larva, the host remains in this developmentally arrested state until death. Teratocytes, cells released at egg hatch from extra‐embryonic serosal membranes of some wasp parasites, inhibit growth and development when injected into host larvae independent of other parasite factors (e.g. venom, polydnavirus). Synthesis of some developmentally regulated, abundantly expressedHeliothis virescenshost proteins is inhibited in hosts parasitized byMicroplitis croceipesand by teratocyte injection. A cDNA encoding a 13.9 kDa protein (TSP14) that inhibited protein synthesis, growth and development was isolated from a protein fraction secreted by teratocytes. TSP14 appears to be responsible, in part, for the teratocyte‐mediated inhibition of host growth and development. Interestingly, this cDNA encoded a cysteine‐rich amino acid motif similar to that described fromCampoletis sonorensispolydnavirus, a mutualistic virus that enables wasp parasitization of lepidopteran larvae. Moreover, TSP14 inhibited protein synthesis in a dose‐dependent manner in rabbit reticulocyte lysate and wheat germ extract translation systems. We hypothesize that some wasp parasites inhibit translation as a general means to regulate and redirect lepidopteran host physiology to support endoparasite development.
Rheological properties of mixed muscle/nonmuscle protein emulsions treated with transglutaminase at two ionic strengths
Authors: Ramírez‐Suárez Juan C. , Xiong Youling L.
Published: September 2003

This study was conducted to determine the effect of transglutaminase on emulsifying properties and rheology of emulsion gels of mixed myofibrillar (MPI) and whey (WPI) or soy (SPI) protein isolates in aqueous solutions with (μ ∼ 0.6) or without (μ ∼ 0) 0.6 m NaCl at pH 6.5. Mixed MPI/WPI or MPI/SPI had a greater (P < 0.05) emulsifying activity but a reduced emulsion storage stability when compared with MPI alone at both ionic strength conditions. The enzyme treatment had a minor effect on protein emulsifying activity, but tended to decrease emulsion stability because of promoting flocculation. Mixed protein emulsions in salt‐free solution formed a gel upon heating to about 50 °C; however, the gel elasticity was less than that of the MPI control emulsion. The addition of 0.6 m NaCl lowered the onset gelling temperature, altered the rheological pattern of the gel, but minimally affected the final gel strength; while the transglutaminase treatment resulted in a higher gel elasticity for all emulsion samples. The results suggest that transglutaminase influenced the rheological properties of mixed muscle/nonmuscle protein emulsion gels mainly through affecting the interaction or cross‐linking of oil droplets and not the physical characteristics of the fat globule membrane per se.
Variation in the form of iron in beef and lamb meat and losses of iron during cooking and storage
Authors: Purchas R. W. , Simcock D. C. , Knight T. W. , Wilkinson B. H. P.
Published: September 2003

Iron levels were lower in semitendinosus muscle of beef and lamb than in longissimus or triceps brachii muscles, and were lower for muscles of male than female lambs, but were similar for muscles from bulls, heifers and mature cows. Soluble proportions of haem iron were higher for beef than lamb (66% vs. 56% of total iron, P < 0.0001), and percentages, as insoluble haem iron or insoluble and soluble non‐haem iron, were lower in beef. For beef semitendinosus muscle, increases in cooking time and temperature led to losses of soluble iron and haem iron, with increases in insoluble and non‐haem forms of iron, and also in the level of iron in the cooking juice. Losses of iron in drip from a free meat sample or a sample on a pad were over 90% soluble haem iron and were greater following freezing and thawing due mainly to higher volumes of drip.
Electrosynthesis of κ‐carrageenan–ovalbumin complexes
Authors: Lii Cheng‐yi , Chen Hua‐han , Lu Shin , Tomasik Piotr
Published: September 2003

Electrosynthesis ofκ‐carrageenan–ovalbumin complexes, in alkaline solution and containing both components in ratios varying from 1 : 5 to 5 : 1, is described. Complexes had compositions varying from 1 : 10 to 1 : 1.8. Components were covalently bound, as deduced from the insolubility of the complexes in 7 murea, the infrared spectra, and thermogravimetric studies. The thermal stability of these complexes was higher than that ofκ‐carrageenan and lower than that of ovalbumin.
Acceptability of snacks produced by the extrusion of amaranth and blends of chickpea and bovine lung
Authors: Chávez‐Jáuregui Rosa N. , Cardoso‐Santiago Raquel A. , Silva Maria E. M. Pinto e , Arêas José A. G.
Published: September 2003

Two snacks, one containing chickpea and either 0, 5 or 10% bovine lung and another with pure amaranth were developed to replace traditional snacks made of maize. These new snacks had improved nutritional quality and their acceptability was assessed by sensory analysis. The tests showed that these products were highly acceptable and comparable with commercial brands. A pizza snack flavoured with amaranth had an acceptability rating that was not significantly different from the commercial maize counterpart. The same applied to bacon flavoured chickpea/lung snacks. This work demonstrates that it is feasible to produce a highly acceptable snack with high nutritional quality that could be useful in nutritional programmes to combat malnutrition. Replacement of commercial snacks based on maize by those developed in this study would benefit young consumers of these types of products.
Nutritional evaluation, with emphasis on protein quality, of maize‐based complementary foods enriched with soya bean and cowpea tempe
Authors: Osundahunsi O. F. , Aworh O. C.
Published: September 2003

Tempe was prepared from dehulled, cooked soya beans and cowpea by using Rhizopus oligosporus fermentation. Four complementary foods, containing 50–80% maize flour or ‘ogi’ flour, were prepared from blends of maize flour, ‘ogi’ flour and tempe flour with or without the addition of melon seed flour. The complementary foods were much higher in protein (18.6–19.7%) and fat (8.2–9.4%) than ‘ogi’ and, except for lower ash contents, were comparable in proximate composition with typical commercial complementary foods produced by food multinationals in Nigeria. There were no significant differences in food efficiency ratio, protein efficiency ratio, net protein retention, packed cell volume, haemoglobin, red blood cells, white blood cells, total serum protein and weights of liver, pancreas, kidney and adrenal gland of rats fed the maize‐based complementary foods enriched with soya bean and cowpea tempe relative to those fed a casein diet.
The Human Genome Project – threat or promise?
Authors: Carmichael B.
Published: September 2003

This paper reflects on some of the arguments against screening from the perspective of a relative of individuals with Fragile X syndrome. It proposes to think about intellectual disability (ID) as including a wide range of limitations beyond that of only the mental handicap. It argues that these limitations impose conditions upon both people with disabilities and their parents, as well as upon their siblings, that in various ways amount to suffering. The claim that people with disabilities are enriching the lives of their relatives is rejected. Furthermore, it is argued that those who ascribe a high moral status to people with disabilities tend to neglect that society does not make much of an effort to offer the necessary support to materialize this status. The claim that screening negatively affects the moral status of persons with ID is rebutted on grounds of the freedom of choice.
Prenatal genetic screening for intellectual disability
Authors: Edwards S. D.
Published: September 2003

Background This paper argues that the main ground for the moral justification of screening and termination of foetuses on grounds of intellectual disability stems from a conception of what it is to lead a good human life.

Method Having established this claim, three well‐known philosophical theories of a good human life are briefly presented.

Conclusion In the light of consideration of these theories, it is proposed that life with intellectual disability is not necessarily incompatible with the conditions necessary for leading a good human life.
Identity, difference and the ethical politics of prenatal testing
Authors: Stainton T.
Published: September 2003

This paper explores the role of identity in relation to the ethics of prenatal testing for conditions that cause intellectual disabilities. Specifically, it considers the question of identity and the moral status of the fetus. It argues that both the arguments in favour and opposed to prenatal testing mistakenly presuppose that there is no moral status attached to the fetus. That status is grounded in an identity‐constituting characteristic, such as ‘intellectual disability’, which is brought about by the purpose of genetic testing, and the meaning of which is culturally constructed. This paper examines the implications this has for the debate around both prenatal testing and termination in general and considers the nature of the ethical politics which follows from this position with regard to prenatal testing related to intellectual disability.
Tragedy and catastrophe: contentious discourses of ethics and disability
Authors: Clapton J.
Published: September 2003

Undertaking theoretical‐conceptual research, this paper identifies and explores two dominant discourses that seemingly underpin ethical considerations about people with intellectual disability in this current biotechnological era. The discourses, identified astragedyandcatastrophe, are constructed from conjunctions of particular theoretical understandings of disability and particular frameworks of ethics. For example, both tragedy and catastrophe are founded upon notions of disability as personal tragedy; and ethics, especially bioethics, primarily practised as medical ethics. What differs between the discourses is the apparent intent of each, and subsequently the arena in which they are activated. This paper asserts that the identification and deconstruction of these discourses, and their implicit ethical agendas, cannot be ignored and indeed should be challenged, when considering the impact of technological and scientific advances, such as the Human Genome Project. However, there has been little attention given in contemporary ethical discussions as to whether these discourses are contestable, or the power base of their constructions questionable. In fact, the insertion of ‘counterstories’ from relational experiences with people with disability may offer both alternative understandings and a more appropriate ethical platform from which to engage in critical discussions. The challenges are, then, whether these counterstories can be heard in such a climate; and what currency will bioethics, as a discipline, give them against the very powerful and partnering disciplines controlling the biotechnological revolution?
On certainty, reflexivity and the ethics of genetic research into intellectual disability
Authors: Goodey C. F.
Published: September 2003

History seems to show us that any definition of intellectual disability (ID) including our current one has no timeless, certain validity, and that definitions are made only in ethical contexts. It is difficult to find a terra firma on which to discuss this sceptical claim alongside the claim to certain knowledge assumed in genetics and much of bioethics. Perhaps a transhistorical basis can be found instead in the motives of people constructing ID, and in the substratum of unconditionality in human relationships.
Total cholesterol and mortality in the elderly
Authors: Casiglia E. , Mazza A. , Tikhonoff V. , Scarpa R. , Schiavon L. , Pessina A. C.
Published: September 2003

Abstract Casiglia E, Mazza A, Tikhonoff V, Scarpa R, Schiavon L, Pessina AC (Department of Clinical and Experimental Medicine, University of Padova, Italy). Total cholesterol and mortality in the elderly. J Intern Med 2003; 254: 353–362.

Objective. To evaluate, at a population level, whether total cholesterol (TC) is a risk factor of mortality. To verify whether or not this is true for both genders.

Design. Population‐based, long‐lasting, prospective study.

Setting. Institutional epidemiology in primary care.

Subjects. A total of 3257 subjects aged 65–95 years, recruited from Italian general population.

Intervention. None.

Main outcome measures.

Total cholesterol was measured, analysed as a continuous variable and then divided into quintiles and re‐analysed. For each quintile, the multivariate relative risk (RR) of mortality adjusted for confounders was calculated in both genders. Stratification of mortality risk by TC quintiles, body mass index and cigarette smoking was also performed in both genders.

Results. Total cholesterol levels directly predicted coronary mortality in men [RR being in the fifth rather than in the first quintile: 2.40 (1.40–4.14)] and any other mortality in women. It also inversely predicted miscellaneous mortality in both genders. This trend was more evident when low cholesterol was associated with malnutrition or smoking.

Conclusions. High TC remains a strong risk factor for coronary mortality in elderly men. On the other hand, having a very low cholesterol level does not prolong survival in the elderly; on the contrary, low cholesterol predicts neoplastic mortality in women and any other noncardiovascular mortality in both genders.
A 5‐year follow‐up study of disease incidence in men with an abnormal hormone pattern
Authors: Rosmond R. , Wallerius S. , Wanger P. , Martin L. , Holm G. , Björntorp P.
Published: September 2003

Abstract Rosmond R, Wallerius S, Wanger P, Martin L, Holm G, Björntorp P (The Cardiovascular Institute, Sahlgrenska University Hospital, Göteborg; and Huddinge University Hospital, Huddinge; Sweden). A 5‐year follow‐up study of disease incidence in men with an abnormal hormone pattern. J Intern Med 2003; 254: 386–390.

Objectives. Previous studies have suggested that abnormal levels of cortisol and testosterone might increase the risk of serious somatic diseases. To test this hypothesis, we conducted a 5‐year follow‐up study in middle‐aged men.

Methods. A population‐based cohort study conducted in 1995 amongst 141 Swedish men born in 1944, in whom a clinical examination supplemented by medical history aimed to disclose the presence of cardiovascular disease (CVD) (myocardial infarction, angina pectoris, stroke), type 2 diabetes and hypertension were performed at baseline and at follow‐up in the year 2000. In addition, salivary cortisol levels were measured repeatedly over the day. Serum testosterone concentrations were also determined. Using the baseline data, an algorithm was constructed, which classified the secretion pattern of cortisol and testosterone from each individual as being normal or abnormal.

Results. By the end of follow‐up, men with an abnormal hormone secretion pattern (n = 73) had elevated mean arterial pressure (P = 0.003), fasting insulin (P = 0.009) and insulin : glucose ratio (P = 0.005) compared with men with a normal secretion pattern (n = 68). Body mass index, waist circumference, and waist : hip ratio were significantly elevated in both groups. However, the 5‐year incidence of CVD, type 2 diabetes, and hypertension were significantly higher (P < 0.001) in men with an abnormal neuroendocrine secretory pattern compared to men with a normal pattern.

Conclusions. These data suggest that an abnormal neuroendocrine secretory pattern is prospectively associated with an increased incidence of cardiovascular‐related events and type 2 diabetes.
Preproghrelin Leu72Met polymorphism in patients with type 2 diabetes mellitus
Authors: Ukkola O. , Kesäniemi Y. A.
Published: September 2003

Abstract Ukkola O, Kesäniemi YA (University of Oulu, Oulu, Finland). Preproghrelin Leu72Met polymorphism in patients with type 2 diabetes mellitus. J Intern Med 2003; 254: 391–394.

Objectives. The association between the Leu72Met polymorphism of the preproghrelin gene and diabetic complications was examined in patients with type 2 diabetes mellitus.

Subjects and methods. A total of 258 patients with type 2 diabetes mellitus and 522 control subjects were screened. Genotypes were determined by polymerase chain reaction technique. The diagnosis of coronary heart disease was based on clinical and ECG criteria. Laboratory analyses were carried out in the hospital laboratory.

Results. No differences in the genotype distributions and allele frequencies of the preproghrelin Leu72Met polymorphism were found between type 2 diabetes mellitus patients and controls. The polymorphism was not associated with macro‐ or micro‐angiopathy or hypertension. However, Leu72Met polymorphism was associated with serum creatinine (P = 0.006) and lipoprotein(a) [Lp(a)] levels (P = 0.006) with Leu72Leu subjects showing the highest values. This association was observed only amongst diabetic group.

Conclusions. The Leu72Met polymorphism of the preproghrelin gene was not related to cardiovascular disease in type 2 diabetes mellitus patients. Leu72Met polymorphism was, however, associated with serum creatinine and Lp(a) levels in diabetic patients. The mechanism might be associated with a possible change in ghrelin product and its somatotropic effect.
Novel anticoagulant agents: introduction
Authors: Schulman S.
Published: September 2003

Abstract Schulman S (Karolinska Hospital, Stockholm, Sweden). Novel anticoagulant agents: introduction (Minisymposium). J Intern Med 2003; 254: 308–312.

In this Minisymposium three principles for anticoagulant therapy are discussed and examples of novel, selective coagulation inhibitors at the stage of advanced clinical trials are given.

This introduction attempts to explain the different mechanisms of action on a broad scale, and also includes a brief look at effects on inflammation and cancer.
Recombinant nematode anticoagulant protein c2 and other inhibitors targeting blood coagulation factor VIIa/tissue factor
Authors: Lee A. Y. Y. , Vlasuk G. P.
Published: September 2003

Abstract Lee AYY, Vlasuk GP (McMaster University, Hamilton, ON, Canada; and Corvas International, Inc., San Diego, CA, USA). Recombinant nematode anticoagulant protein c2 and other inhibitors targeting blood coagulation factor VIIa/tissue factor (Minisymposium). J Intern Med 2003; 254: 313–321.

Originally isolated from a haematophagous hookworm, recombinant nematode anticoagulant protein c2 (rNAPc2) is an 85‐amino acid protein with potent anticoagulant properties. Unlike conventional anticoagulants that attenuate blood coagulation via inhibition of thrombin or activated factor X (FXa) at the downstream portion of the cascade, rNAPc2 is a potent inhibitor of the activated factor VII/tissue factor complex (FVIIa/TF), the key physiological initiator of blood coagulation. Its mechanism of action requires prerequisite binding to circulating FXa or zymogen factor X (FX) to form a binary complex prior to its interaction and inhibition of membrane‐bound FVIIa/TF. The binding of rNAPc2 to FX results in an elimination half‐life of longer than 50 h following either subcutaneous or intravenous administration. Recombinant NAPc2, like other inhibitors of FVIIa/TF including tissue factor pathway inhibitor (TFPI) and active site‐blocked FVIIa (ASIS, FFR‐rFVIIa or FVIIai), may have a promising role in the prevention and treatment of venous and arterial thrombosis, as well as potential efficacy in the management of disseminated intravascular coagulopathies because of their potent and selective inhibition of FVIIa/TF.
Oral direct thrombin inhibitors in clinical development
Authors: Gustafsson D.
Published: September 2003

Abstract Gustafsson D (AstraZeneca R&D, Mölndal, Sweden). Oral direct thrombin inhibitors in clinical development (Minisymposium). J Intern Med 2003; 254: 322–334.

Thrombin has long been a target for development of oral anticoagulants but it has been difficult to find synthetic inhibitors with a desirable combination of pharmacodynamic and pharmacokinetic properties. However, there are now two oral direct thrombin inhibitors (DTIs) in clinical development, ximelagatran (ExantaTM) and BIBR 1048. Both are prodrugs with two protecting groups that are eliminated after absorption from the gastrointestinal tract. Their main active substances, melagatran and BIBR 953, are both potent and selective DTIs. In experimental models of thrombosis, melagatran has been shown to have a shallower dose–response curve than warfarin and, therefore, a better separation between efficacy and bleeding. Oral bioavailability, measured as the plasma concentration of the active metabolite, seems to be higher for ximelagatran (20%) than for BIBR 1048 (estimated to 5%). BIBR 953 has a longer half‐life (about 12 h) than does melagatran (3–5 h) after oral administration of BIBR 1048 and ximelagatran, respectively. Both melagatran and BIBR 953 are mainly eliminated via the renal route. The variability of the plasma concentration of melagatran after oral administration of ximelagatran is low. There are no clinically relevant interactions with food or cytochrome P450 metabolized drugs and ximelagatran. In clinical studies, ximelagatran has been administered in a twice‐daily fixed‐dose regimen without coagulation monitoring. Results of published clinical studies are encouraging, both with regard to efficacy and bleeding. Major indications in Phase III studies with ximelagatran are the prevention of venous thromboembolism (VTE) in hip and knee replacement surgery, treatment and long‐term secondary prevention of VTE and prevention of stroke in patients with nonvalvular atrial fibrillation. It is anticipated that with a favourable outcome of the Phase III clinical studies new oral DTIs, with the oral fixed‐dose regimen without routine coagulation monitoring, will ease the use of today's anticoagulant therapy.
Short‐ and long‐acting synthetic pentasaccharides
Authors: Koopman M. M. W. , Büller H. R.
Published: September 2003

Abstract Koopman MMW, Büller HR (Academic Medical Centre, Amsterdam, The Netherlands). Short‐ and long‐acting synthetic pentasaccharides (Minisymposium). J Intern Med 2003; 254: 335–342.

Inhibition of activated coagulation factor X (FXa) is an attractive target for antithrombotic treatment strategies, because of the central position of FXa in the coagulation cascade. Most of the now available anticoagulant drugs have inhibitory effects not only on FXa, but also on thrombin. With the development of pentasaccharides, a new class of antithrombotic agents has emerged that acts by specific inhibition of FXa and lacks activity against FIIa. Fondaparinux, the first synthetic short‐acting pentasaccharide, has been evaluated, in a large phase II and III clinical programme concerning prophylaxis and treatment of venous thromboembolism and also in phase II studies in patients with acute coronary syndromes. Idraparinux, the long‐acting pentasaccharide, has been studied in a dose‐finding study in patients with established deep‐vein thrombosis and phase III studies are now planned in patients with venous thromboembolism and in patients with atrial fibrillation.
Properties of dual‐curable luting composites polymerized with single and dual curing modes
Authors: Tanoue N. , Koishi Y. , Atsuta M. , Matsumura H.
Published: September 2003

summary  The purpose of this study was to evaluate the influence of visible‐light exposure on water absorption, solubility and colour stability of dual‐curable luting composites. Using eight dual‐curable luting composites (2bond2, Bistite II, G‐Cera Cosmotech II, Imperva Dual, Linkmax, Lute‐It, Panavia Fluoro Cement and Variolink II), disk specimens were prepared by the following two methods: (i) dual‐cured specimens; exposed with visible‐light from a light‐curing unit, and (ii) chemical‐cured specimens; chemically polymerized without exposure. Five specimens were produced for each material and curing mode. Water absorption and solubility were determined according to standardized testing methods, and the data were compared using analysis of variance (anova) and contrasts. With regard to colour stability, the colour difference (ΔE*) values between 24 h and the other immersion periods (1, 2, 3, 4, 8, 12, 16, 20 and 24 weeks) were calculated and then analysed by repeated measure anova. The dual‐cured specimens exhibited significantly lower solubility values than the chemical‐cured specimens except for the Lute‐It material. The dual‐cured Linkmax material exhibited the lowest solubility (0·51 ± 0·01 μg mm−3) and the lowest ΔE* value after 24 weeks (2·64 ± 0·39). The dual‐curable luting composites should be light‐exposed after seating of restorations in order to reduce water absorption and solubility, and to improve colour stability.
Handy measurement for tongue motion and coordination with laryngeal elevation at swallowing
Authors: Tsuga K. , Hayashi R. , Sato Y. , Akagawa Y.
Published: September 2003

summary  At the oral stage of swallowing, the tongue plays a major role and proper tongue performance is necessary to form the bolus and transfer it to the pharynx. For the present study we built a prototype device for safe and handy objective estimation of tongue motion and coordination with laryngeal elevation at swallowing. The device records tongue pressure by means of two strain gauge pressure transducers aligned 20 mm apart on a brass strap placed along the palatal midline. Laryngeal vibration is recorded with piezo‐electric acceleration transducers. Time differences between pressure onset at the anterior and posterior transducers and the first spike from laryngeal vibration are measured. Ten healthy subjects were asked five times to swallow 5 mL of water. Pressure onset at the anterior transducer preceded posterior pressure by 294 ± 164 ms. Given the distance between the transducers, the tongue contracted (squeezed) at a speed of 93 ± 60 mm s−1. Laryngeal vibration occurred 671 ± 175 ms after the onset of anterior pressure. There was considerable variation in these parameters between subjects. Though the data is limited, the device successfully and easily revealed certain aspects of tongue motion and coordination with laryngeal elevation.
In vitro diffusion of hydroxyl ions through root dentine from various calcium hydroxide medicaments
Authors: Sevi̇may S. , Kalayci A. , Yilmaz S.
Published: September 2003

summary  The purpose of this study was to determine diffusion of hydroxyl ions through dentine from different calcium hydroxide [Ca(OH)2] medicaments. Forty‐five single‐rooted teeth were instrumented and cavities (3 mm in diameter and 1 mm in depth) were prepared on the facial surface of each root. After smear layer was removed with 17% EDTA all surfaces of roots, except cavities, were coated with nail polish. Teeth were randomly divided into four experimental groups (each 10 samples) and a control group (five samples). They were filled with: group 1, Ca(OH)2 and distilled water mixture; group 2, TempCanal; group 3, Calasept; and group 4, Ca(OH)2 plus point. Control group, in which nothing was applied to the canals. All samples were immersed in distilled water maintained at 37 °C. pH values were measured at 1 h, 2 h, 3 h, 24 h, 48 h, 72 h, 4 days, 5 days, 6 days, 7 days and 14 days. Ca(OH)2‐distilled water mixture and TempCanal showed highest pH values at 24 h. Calasept, Ca(OH)2 plus point and control showed highest pH values at 3 h. Time intervals after 24 h, Ca(OH)2‐distilled water mixture, TempCanal and Calasept showed higher pH values than Ca(OH)2 plus point, with a statistically significant difference (P < 0·05). The pH value of Ca(OH)2 plus point was lower than the values of other materials after 3 h. This study indicates that non‐setting Ca(OH)2 based materials have an effective release of hydroxyl ions compared with Ca(OH)2 plus point.
Marginal adaptation of class II resin composite restorations using incremental and bulk placement techniques: an ESEM study
Authors: Idriss S. , Habib C. , Abduljabbar T. , Omar R.
Published: September 2003

summary  This in vitro study compared marginal gap formation in class II resin composite restorations. Forty caries‐free extracted molars were prepared in a standardized manner for class II restoration by one of four methods: bulk‐ or incrementally‐placed light‐activated resin composite (Amelogen), and bulk‐ or incrementally‐placed chemically activated composite (Rapidfill). The restored teeth, after finishing and polishing, and thermocycling, were examined using environmental scanning electron microscopy. Marginal gap measurements at predetermined facial and lingual margin sites showed no significant differences between the two sites within any of the groups. Both the light‐ and the chemically‐activated restorations showed no significant differences in mean marginal gap sizes whether they were placed by incremental or bulk techniques. Amelogen restorations placed by both methods had significantly larger margin gaps than those of each of the Rapidfill groups (P < 0·05). Thus, although method of placement of a given material had no significant effect on the quality of marginal adaptation, both of the chemically activated resin composite restorations produced significantly smaller marginal gaps than both the bulk‐ and incrementally‐placed light‐activated composites.
Resin‐bonded fixed partial denture retention: a retrospective 13‐year follow‐up
Authors: Zalkind M. , Ever‐Hadani P. , Hochman N.
Published: September 2003

summary  A total of 51 resin‐bonded fixed partial dentures (RBFPDs) were inserted under controlled clinical conditions and evaluated over a period of 13 years.

Three levels of survival were defined: complete survival (no debonding); functional survival (loss of retention on one occasion with rebonding of the original RBFPD); and multiple survival (loss of retention on several occasions with rebonding of the original RBFPD).

The effect of the aetiology, location (anterior/posterior or maxillary/mandibulary) and number of units of the missing tooth on RBFPD survival rates were investigated. The mean survival times and confidence levels were determined for each survival category, using the Kaplan–Meier procedure. The relative risks were calculated by the Cox regression procedure.

The overall complete survival level of the study population at the end of the follow‐up period was 85 months ± 13%. Rebonding the RBFPDs once increased the overall functional survival rate to 112 months ± 10% and multiple rebonding led to a further increase to 131 months ± 8%. The RBFPD placement under conditions of good periodontal support in which orthodontic treatment was not required, such as trauma among other factors, showed significantly higher survival rates than those placed after periodontal or orthodontic treatment. This indicates that, under both these conditions, RBFPDs may serve as long‐term or semi‐permanent restorations.
Clinical longevity of resin‐bonded bridges bonded using a vinyl‐thiol primer
Authors: Hikage S. , Hirose Y. , Sawada N. , Endo K. , Ohno H.
Published: September 2003

summary  The purpose of this study is to clinically confirm the adhesive effect of a vinyl‐thiol primer (V‐Primer) for precious alloys. Further, we examined the failure of resin‐bonded bridges (RBBs) in order to improve the clinical longevity of RBBs, and to analyse the causes of failure. Twenty‐six RBBs were bonded with V‐primer and Super Bond C & B between May 1987 and December 1997 in the Dental Clinic of the Health Sciences University of Hokkaido. The RBBs were made of silver–palladium–gold alloy or metal–ceramic gold alloys. V‐primer was effective in bonding Super Bond C & B to the RBBs made of silver–palladium–gold alloys. Ten prostheses had functioned satisfactorily for 8–11 years. However, six of the 26 RBBs had become detached. In four of the six failed RBBs, the type of bond failure was a mixture fracture in the resin–enamel interface. Our results suggest that: (1) V‐primer is effective on RBBs made of silver–palladium–gold alloys. (2) Mechanical retention is necessary for retainers to improve the longevity of RBBs when the V‐primer is applied to RBBs made of precious alloys without copper. (3) The RBB should not be applied to abutment teeth that have differences in tooth mobility.
Effects of activator on masticatory muscle activity during daytime and sleep
Authors: Ueda H. M. , Tabe H. , Kato M. , Nagaoka K. , Nakashima Y. , Shikata N. , Tanne K.
Published: September 2003

summary  The purpose of this study was to investigate masticatory muscle activity with and without the use of an activator during daytime and sleep, and further to focus on the changes in muscle activity produced by the daytime use. The subjects in this study were 10 healthy males (mean age: 27·6 years). A portable electromyogram (EMG) recording device was used to record the activity from the right temporal, masseter and digastric muscles. After recording, the integrated EMG values (µV s) were measured. The muscle activity was lower during sleep than during daytime, irrespective of the use of the activator. In sleep‐time, temporal and digastric muscle activity was significantly decreased, although masseter muscle activity presented no significant differences. With the activator in use, the digastric muscle activity tended to increase in comparison with the elevator muscles during daytime and sleep. Although the activity of both elevator muscles was diminished by use of the activator during sleep in all subjects, some subjects showed an increase during daytime. These results suggested that the activator should be used, if possible, not only during sleep, but also during daytime and clenched on consciously to obtain the adaptation and development of the masticatory muscles for the ‘re‐training of the muscles’ at a new favourable mandibular position.
The effect of oscillation, low seating force and dentine surface treatment on pulpward pressure transmission during crown cementation: a laboratory study
Authors: Cherkasski B. , Wilson P. R.
Published: September 2003

summary  The aim of the present research was to evaluate intra‐pulpal pressure with respect to a combination of factors that are known to reduce pulpward pressure transmission in the laboratory while maintaining acceptable seating of the crowns. Thirty premolars were prepared for full crowns and individual crowns were cast. Ten teeth were etched prior to crown cementation with 100 N seating force. Crowns of groups 2 and 3 were cemented with 10 N force, after dentine sealing with bonding agent. Group two received, in addition, oscillating seating force during cementation. Pulp chamber pressure during cementation and marginal seating discrepancy after cementation were recorded. Group 1 showed significantly higher pressure mean 600 Pa and better crown seating (mean −22 μm) compared with group two (mean 144 Pa and 24 μm) and group 3 (mean 102 Pa and 44 μm) (P=0·001). Low seating forces combined with die spacer and sealing of dentinal tubules resulted in significant reduction of pressure transmitted into the pulp chamber during crown cementation. It is suggested that pre‐impression sealing of dentine be considered for crown preparations on vital teeth.
Associations between self‐reported dental status and diet
Authors: Daly R. M. , Elsner R. J. F. , Allen P. F. , Burke F. M.
Published: September 2003

summary  The purpose of this study was to develop a battery of dental, nutritional and psychological health survey measures and to use this survey instrument to explore links between age, tooth loss and dietary risk. The survey was undertaken in a dental school and hospital. Forty‐nine consecutive patients (age range 25–74 years) participated in this pilot study and completed the health survey instrument. A quarter of the patients reported changing dietary habits due to dental problems, 56% reported difficulty in chewing as a result of problems with their teeth or dentures, and 36% reported having to interrupt meals due to dental difficulties. Tooth number was associated with MNA scores (0·35, P = 0·03, Pearson's correlation coefficient) and reported number of foods eaten (0·33, P = 0·04, Pearson's correlation coefficient) from the questionnaire checklist. Lower MNA scores were associated with age (F = 6·54; d.f. = 1, 46; P < 0·01) indicating that older adults were more at risk of poor nutritional status. Overall health was not rated as an important factor influencing food choice, and only 14% of the sample felt that they had nutritional problems. Poor diet and impaired food choice was associated with declining numbers of teeth and increasing age. Older adults may require dietary advice to increase awareness of the importance of a healthy diet.
Assessing microleakage of different class V restorations after Er:YAG laser and bur preparation
Authors: Corona S. A. M. , Borsatto M. C. , Pecora J. D. , De Sá Rocha R. A. S. , Ramos T. S. , PALMA‐Dibb R. G.
Published: September 2003

summary  This study assessed in vitro marginal leakage of class V cavities prepared by turbine and Er:YAG laser and restored with different materials. Sixty cavities with enamel and dentine margins were prepared and assigned to six groups: I, II, III by turbine and IV, V, VI by Er:YAG laser. The following restorative systems were used: groups I and IV: Bond 1 + Alert; II and V: Fuji II LC; III and VI: SBMP + Dispersalloy. After finishing, specimens were thermocycled for 8 h and 45 min (500 cycles), isolated, immersed in a 0·2% Rhodamine B solution, sectioned oro‐facially and analysed for leakage. The dye penetration means (%) were: occlusal I: 10·09 (±21·28), II: 3·25 (±10·27), III: 0, IV: 41·77 (±42·48), V: 23·37 (±33·79), VI: 12·66 (±24·06); cervical I: 16·49 (±26·67), II: 4·34 (±13·71), III: 0, IV: 37·71 (±30·47), V: 39·56 (±43·35) and VI: 72·53 (±37·79). The use of Er:YAG laser for cavity preparation yielded higher degree of marginal leakage, as compared with the use of conventional air‐turbine. The enamel interface provided better marginal sealing, comparing with dentine/cementum margin. As to the cavity preparation device (i.e. laser or bur), the analysis of the results showed that bonded amalgam and Fuji II LC provided less infiltration, than Alert. On the other hand, for lased cavities, Alert provided the best results, similar to those of Fuji II LC and superior to those reached by bonded amalgam.
Occlusal phase of gum‐chewing strokes
Authors: Hayasaki H. , Saitoh I. , Throckmorton G. S. , Iwase Y. , Nakata S. , Nakata M.
Published: September 2003

summary  The occlusal phase of chewing is especially interesting because food particles are being pulverized in this phase. For efficient chewing the upper and lower teeth must come together in a congruent fashion with less variation than in other phases. To examine this expectation the chewing motions of 28 women were recorded optoelectrically, and their frontal and sagittal angles of the closing and following opening strokes were measured at 3·0 mm (3‐D linear distance) of opening. Closing strokes were more stable than opening strokes. The frontal angle was correlated with the sagittal angle during closing. The opening and closing sagittal angles were moderately correlated, and the opening and closing frontal angles were negatively correlated at the intersubject level. No direct association was found between the closing strokes and following opening strokes at the intra‐subject level. These results suggest that closing strokes are more stable than opening strokes, resulting in efficient mastication.
AHP2 is required for bivalent formation and for segregation of homologous chromosomes in Arabidopsis meiosis
Authors: Schommer Carla , Beven Ali , Lawrenson Tom , Shaw Peter , Sablowski Robert
Published: September 2003

A new Arabidopsis meiotic mutant has been isolated. Homozygous ahp2‐1 (Arabidopsis homologue pairing 2) plants were sterile because of failure of both male and female gametophyte development. Fluorescent in situ hybridisation showed that in ahp2‐1 male meiocytes, chromosomes did not form bivalents during prophase I and instead seemed to associate indiscriminately. Chromosome fragmentation, chromatin bridges and unbalanced segregation were seen in anaphase I and anaphase II. The ahp2‐1 mutation was caused by a T‐DNA insertion in an Arabidopsis homologue of meu13+, which has been implicated in homologous chromosome pairing during meiosis in Schizosaccharomyces pombe. Our results suggest that meu13+ function is conserved in higher eukaryotes and support the idea that Arabidopsis, yeast and mouse share a pairing pathway that is not present in Drosophila melanogaster and Caenorhabditis elegans.
Co‐expression of N‐terminal truncated 3‐hydroxy‐3‐methylglutaryl CoA reductase and C24‐sterol methyltransferase type 1 in transgenic tobacco enhances carbon flux towards end‐product sterols
Authors: Holmberg Niklas , Harker Mark , Wallace Andrew D. , Clayton John C. , Gibbard Carl L. , Safford Richard
Published: September 2003

The enzymes 3‐hydroxy‐3‐methylglutaryl CoA reductase (HMGR) and C24‐sterol methyltransferase type 1 (SMT1) have been proposed to be key steps regulating carbon flux through the sterol biosynthesis pathway. To further examine this hypothesis, we co‐expressed the catalytic domain of Hevea brasiliensis HMGR (tHMGR) and Nicotiana tabacum SMT1 in tobacco, under control of both constitutive and seed‐specific promoters, resulting in increased accumulation of total sterol in seed tissue by 2.5‐ and 2.1‐fold, respectively. This enhancement is greater than when tHMGR and SMT1 were expressed singularly where, for example, seed‐specific expression enhanced total sterols by 1.6‐fold. Significantly, the relative level of 4‐desmethyl sterols (end‐product sterols) was higher in seed co‐expressing tHMGR and SMT1 from seed‐specific promoters (79% of total sterols) than when co‐expressed from constitutive promoters (59% of total sterols) and similar to wild‐type seed (80% of total sterols). These results demonstrate that HMGR and SMT1 work in concert to control carbon flux into end‐product sterols and that the sterol composition can be controlled by the temporal activity of the promoters driving transgene expression. In addition, constitutive expression of the transgenes resulted in elevated accumulation of substrates for C4‐demethylation reactions, which indicates that one or several enzymes catalysing such reactions limit carbon flow to end‐product sterols, at least in a physiological situation when the carbon flow is upregulated.
Genome‐wide mRNA profiling reveals heterochronic allelic variation and a new imprinted gene in hybrid maize endosperm
Authors: Guo Mei , Rupe Mary A. , Danilevskaya Olga N. , Yang Xiaofeng , Hu Zihua
Published: September 2003

We have taken a genomic approach to examine global gene expression in the maize endosperm in relation to dosage and parental effects. Endosperm of eight hybrids generated by reciprocal crosses and their seven inbred parents were sampled at three developmental stages: 10, 14, and 21 days after pollination (DAP). These samples were subjected to GeneCalling, an open‐ended mRNA‐profiling technology, which simultaneously analyzes thousands of genes. Results indicated that the overall level of gene expression in the maize endosperm was dosage‐dependent, that is, the gene expression was proportional to the parental genome contribution of 2n maternal : 1n paternal. However, approximately 8% of the genes deviated from such allelic additive expression and exhibited differential expression in hybrids of reciprocal crosses, resembling either maternally or paternally expressed genes. There were more genes with maternal‐like expression (MLE) than those with paternal‐like expression (PLE). Allele‐specific expression analysis of four selected genes using the WAVE denaturing HPLC (dHPLC) system revealed several mechanisms responsible for the deviation from the allelic additive expression in the hybrid endosperm: heterochronic allelic variation, allelic variation in the level of expression, and genomic imprinting. We discovered a novel imprinted gene no‐apical‐meristem (NAM) related protein1 (nrp1) that was expressed only in the endosperm and regulated by gene‐specific imprinting. The nrp1 gene, a putative transcriptional factor, may play an important role in endosperm development.