bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypodontia in an adolescent with the HbSC genotype: a case report
Authors: OREDUGBA F. A.
Published: October 2005

The haemoglobin SC (HbSC) genotype is a variant form of haemoglobin disorder that often presents less frequent clinical symptoms of sickle cell disease (SCD) than the homozygous state (HbSS). Various dental abnormalities, such as enamel hypoplasia, hypomineralization, midline diastema and delayed eruption of the teeth, have been associated with SCD. This report presents the case of an adolescent patient with HbSC who had hypodontia, transposition of a permanent canine, retained primary teeth, multiple carious lesions and poor oral hygiene complicated by sickle cell crisis. This report focuses on the need for preventive care in such patients to reduce functional and aesthetic complications.
Dental caries and associated factors in 12‐year‐old schoolchildren in Thiruvananthapuram, Kerala, India
Authors: DAVID J. , WANG N. J. , ÅSTRØM A. N. , KURIAKOSE S.
Published: October 2005

Objectives. The aims of the present study were to describe the dental health status of 12‐year‐old schoolchildren in Thiruvananthapuram, Kerala, India, and to identify sociodemographic factors, oral health behaviours, attitudes and knowledge related to dental caries experience.

Methods. The study took the form of a cross‐sectional survey of 838 children in upper primary schools. A two‐stage cluster sampling technique was used. Dental caries was measured using World Health Organization criteria. Sociodemographic factors, oral health behaviours, attitudes and knowledge were assessed by a self‐administered questionnaire.

Results. The prevalence of dental caries in the permanent dentition was 27%. The mean number of decayed, missing and filled teeth was 0·5 (SD = 0·9). The decayed component (D) constituted 91% of the total number of decayed, missing and filled teeth (DMFT). Multiple logistic regression analysis showed that children had a higher risk of having dental caries if they lived in urban area [OR = 1·5, 95% confidence interval (CI) = 1·1–2·1], had visited a dentist (OR = 1·6, 95% CI = 1·2–2·2), did not use a toothbrush (OR = 1·9, 95% CI = 1·2–2·9), consumed sweets (OR = 1·4, 95% CI = 1·0–1·9) or performed poorly in school (OR = 1·7, 95% CI = 1·0–2·3).

Conclusions. The prevalence of caries in this sample of 12‐year‐old schoolchildren was low compared to that in other developing countries. The present study indicated that urban living conditions were associated with more dental caries. Since urbanization is rapid in India, oral health promotion at the present time would be valuable to prevent increased caries prevalence.
Dental fluorosis in primary teeth: a study in rural schoolchildren in Shaanxi Province, China
Authors: RUAN J. P. , WANG Z. L. , YANG Z. Q. , BÅRDSEN A. , ÅSTRØM A. N. , BJORVATN K.
Published: October 2005

Objective. The aim of this study was to assess the prevalence and severity of fluorosis in the primary dentition of 7–8‐year‐old Chinese schoolchildren in areas with fluoride concentrations in the drinking water ranging from 0·35 to 7·6 mg L−1.

Subjects and methods. Four hundred and seventy‐two children from 13 different schools were divided into four groups according to the fluoride concentration of the drinking water: (A) ≤ 1·0 mg L−1; (B) 1·1–2·0 mg L−1; (C) 2·1–3·8 mg L−1; and (D) 7·6 mg L−1. Clinical examinations were made under field conditions, and dental fluorosis on the buccal surfaces of all teeth was recorded using the Thylstrup–Fejerskov Index (TFI).

Results. The prevalence of dental fluorosis in primary teeth varied from 6·2% to 96·6% according to the fluoride concentration of the drinking water. The differences of median of TFI scores between all groups were statistically significant (P < 0·001) except for groups B and C. No statistically significant difference in the severity of dental fluorosis was observed between genders. The second primary molars were most severely affected by dental fluorosis. Disregarding group A, TFI scores between 3 and 4 were most frequently recorded. Dental fluorosis was symmetrically distributed in both jaws.

Conclusion. Dental fluorosis is prevalent in the primary teeth of children living in areas supplied with drinking water with fluoride concentrations higher than 1·0 mg L−1. The primary teeth may act as biomarkers of fluoride exposure. The examination of primary teeth may give an early warning of this condition, and thus, provide a basis for intervention to prevent dental fluorosis in the permanent teeth.
Magic trick: a behavioural strategy for the management of strong‐willed children
Authors: PERETZ B. , GLUCK G.
Published: October 2005

Objective. The purpose of this study was to compare the effectiveness of using a magic trick to persuade strong‐willed children who refuse to sit in the dental chair at the first visit with more conventional methods like tell‐show‐do (TSD).

Methods. Seventy children aged 3–6 years of age who were identified as manifesting strong‐willed behaviour were selected for this study. The children were randomly assigned to be managed either by a magic trick distraction or by TSD. There were 35 subjects in each group. The following variables were recorded for each child: time from the beginning of the session to sitting on the dental chair (in minutes); ability to perform a dental examination (yes or no); and Frankl's behavioural category.

Results. Children who were shown a magic trick (Magic+) sat significantly faster on the dental chair than children who were not shown the magic trick (Magic–) (141·2 ± 71·5 and 221·7 ± 110·7 s, respectively). In addition, radiographs could be taken in significantly more Magic+ children (91% and 54%, respectively). When time till sitting on dental chair, radiographs taken and Frankl's behavioural categories were examined by gender, age, first time at the dentist and by parent assessment, the following pattern emerged: (1) Children in the Magic+ group sat on the dental chair significantly faster than children in the Magic– group. (2) Radiographs could be taken for more Magic+ children. (3) The Magic+ children demonstrated more cooperative behaviour (Frankl's categories 3 and 4).

Conclusion. This study demonstrates that a magic trick is able to facilitate two types of cooperative behaviour: (1) it expedites the movement of the child into the dental chair; and (2) it enables the dentist to take radiographs more easily.
Reasons for and parental satisfaction with children's dental care under general anaesthesia
Authors: SAVANHEIMO N. , VEHKALAHTI M. M. , PIHAKARI A. , NUMMINEN M.
Published: October 2005

Objectives. The aim of this study was to describe why healthy children's previous treatment experiences can be reasons for their dental treatment under general anaesthesia (GA), and to describe their parents’ experiences and satisfaction with that treatment.

Subjects and methods. The data cover those children (n = 102) below 16 years of age who, being otherwise healthy, were referred for Public Dental Service GA dental care in Helsinki, Finland, over the course of one year because of serious difficulties in dental treatment. The parents were given a self‐administered questionnaire inquiring about their child's previous experiences of dental care, and about their access to and satisfaction with the present GA treatment. Data on the children's dental state were taken from patient records.

Results. The children's mean age was 6·4 years (SD = 2·6 years), and the mean number of teeth with untreated caries was 7·7 (SD = 3·0). Of the total sample, 32% had undergone four or more previous unsuccessful dental visits. At the time of their first difficulties in dental care, 39% were below 3 years of age. The older the child, the more serious was her or his parents’ ranking of the difficulties met during dental care (P = 0·02). From the parents’ point of view, dental fear was the most important reason for treatment failures, followed by pain. Seeking GA treatment had been easy for 93% of parents, and most of them were also satisfied with their child's present GA treatment.

Conclusions. The most important factors leading to the use of GA, as reported by the parents, are dental fear and repeated unpleasant experiences during dental care, and therefore, these should always be properly diagnosed, prevented and controlled.
The MreB and Min cytoskeletal‐like systems play independent roles in prokaryotic polar differentiation
Authors: Shih Yu‐Ling , Kawagishi Ikuro , Rothfield Lawrence
Published: October 2005

Establishment of an axis of cell polarity and differentiation of the cell poles are fundamental aspects of cellular development in many organisms. We compared the effects of two bacterial cytoskeletal‐like systems, the MreB and MinCDE systems, on these processes in Escherichia coli. We report that the Min proteins are capable of establishing an axis of oscillation that is the initial step in establishment of polarity in spherical cells, in a process that is independent of the MreB cytoskeleton. In contrast, the MreB system is required for establishment of the rod shape of the cell and for polar targeting of other polar constituents, such as the Shigella virulence factor IcsA and the aspartate chemoreceptor Tar, in a process that is independent of the Min system. Thus, the two bacterial cytoskeletal‐like systems act independently on different aspects of cell polarization.
SsgA‐like proteins determine the fate of peptidoglycan during sporulation of Streptomyces coelicolor
Authors: Noens Elke E. E. , Mersinias Vassilis , Traag Bjørn A. , Smith Colin P. , Koerten Henk K. , van Wezel Gilles P.
Published: October 2005

During developmental cell division in sporulation‐committed aerial hyphae of streptomycetes, up to a hundred septa are simultaneously produced, in close harmony with synchromous chromosome condensation and segregation. Several unique protein families are involved in the control of this process in actinomycetes, including that of the SsgA‐like proteins (SALPs). Mutants for each of the individual SALP genes were obtained, and high‐resolution and fluorescence imaging revealed that each plays an important and highly specific role in the control of the sporulation process, and their function relates to the build‐up and degradation of septal and spore‐wall peptidoglycan. While SsgA and SsgB are essential for sporulation‐specific cell division in Streptomyces coelicolor, SsgC–G are responsible for correct DNA segregation/condensation (SsgC), spore wall synthesis (SsgD), autolytic spore separation (SsgE, SsgF) or exact septum localization (SsgG). Our experiments paint a picture of a novel protein family that acts through timing and localization of the activity of penicillin‐binding proteins and autolysins, thus controlling important steps during the initiation and the completion of sporulation in actinomycetes.
Sialic acid transport in Haemophilus influenzae is essential for lipopolysaccharide sialylation and serum resistance and is dependent on a novel tripartite ATP‐independent periplasmic transporter
Authors: Severi Emmanuele , Randle Gaynor , Kivlin Polly , Whitfield Kate , Young Rosie , Moxon Richard , Kelly David , Hood Derek , Thomas Gavin H.
Published: October 2005

Sialylation of the lipopolysaccharide (LPS) is an important mechanism used by the human pathogen Haemophilus influenzae to evade the innate immune response of the host. We have demonstrated that N‐acetylneuraminic acid (Neu5Ac or sialic acid) uptake in H. influenzae is essential for the subsequent modification of the LPS and that this uptake is mediated through a single transport system which is a member of the tripartite ATP‐independent periplasmic (TRAP) transporter family. Disruption of either the siaP (HI0146) or siaQM (HI0147) genes, that encode the two subunits of this transporter, results in a complete loss of uptake of [14C]‐Neu5Ac. Mutant strains lack sialylated glycoforms in their LPS and are more sensitive to killing by human serum than the parent strain. The SiaP protein has been purified and demonstrated to bind a stoichiometric amount of Neu5Ac by electrospray mass spectrometry. This binding was of high affinity with a Kd of ∼0.1 µM as determined by protein fluorescence. The inactivation of the SiaPQM TRAP transporter also results in decreased growth of H. influenzae in a chemically defined medium containing Neu5Ac, supporting an additional nutritional role of sialic acid in H. influenzae physiology.
CsrA and three redundant small RNAs regulate quorum sensing in Vibrio cholerae
Authors: Lenz Derrick H. , Miller Melissa B. , Zhu Jun , Kulkarni Rahul V. , Bassler Bonnie L.
Published: October 2005

Bacteria communicate using a process called quorum sensing which involves production, secretion and detection of signalling molecules called autoinducers. Quorum sensing allows populations of bacteria to simultaneously regulate gene expression in response to changes in cell density. The human pathogen, Vibrio cholerae, uses a quorum‐sensing circuit composed of parallel systems that transduce information through four redundant regulatory small RNAs (sRNAs) called quorum regulatory RNAs (Qrr) to control the expression of numerous genes, most notably those required for virulence. We show that the VarS/VarA two‐component sensory system comprises an additional regulatory input controlling quorum‐sensing‐dependent gene expression in V. cholerae. VarS/VarA controls transcription of three previously unidentified small regulatory RNAs (sRNAs) that are similar to the sRNAs CsrB and CsrC of Escherichia coli. The three V. cholerae sRNAs, which we name CsrB, CsrC and CsrD, act redundantly to control the activity of the global regulatory protein, CsrA. The VarS/VarA‐CsrA/BCD system converges with the V. cholerae quorum‐sensing systems to regulate the expression of the Qrr sRNAs, and thus, the entire quorum‐sensing regulon.
Mrr instigates the SOS response after high pressure stress in Escherichia coli
Authors: Aertsen Abram , Michiels Chris W.
Published: October 2005

The bacterial SOS response is not only a vital reply to DNA damage but also constitutes an essential mechanism for the generation of genetic variability that in turn fuels adaptation and resistance development in bacterial populations. Despite the extensive depiction of the SOS regulon itself, its activation by stresses different from typical DNA damaging treatments remains poorly characterized. Recently, we reported the RecA‐ and LexA‐dependent induction of the SOS response in Escherichia coli MG1655 after exposure to high hydrostatic pressure (HP, ∼100 MPa), a physical stress of which the cellular effects are not well known. We now found this HP mediated SOS response to depend on RecB and not on RecF, which is a strong indication for the involvement of double strand breaks. As the pressures used in this work are thermodynamically unable to break covalent bonds in DNA, we hypothesized the involvement of a cellular function or pathway in the formation of this lesion. A specialized screening allowed us to identify the cryptic type IV restriction endonuclease Mrr as the final effector of this pathway. The HP SOS response and its corresponding phenotypes could be entirely attributed to the HP triggered activation of Mrr restriction activity. Several spontaneously occurring alleles of mrr, incapable of triggering the HP‐induced SOS response, were isolated and characterized. These results provide evidence for a specific pathway that transmits the perception of HP stress to induction of the SOS response and support a role for Mrr in bacterial stress physiology.
An atypical type II topoisomerase from Mycobacterium smegmatis with positive supercoiling activity
Authors: Jain Paras , Nagaraja Valakunja
Published: October 2005

Topoisomerases are essential ubiquitous enzymes, falling into two distinct classes. A number of eubacteria including Escherichia coli, typically contain four topoisomerases, two type I topoisomerases and two type II topoisomerases viz. DNA gyrase and topoisomerase IV. In contrast several other bacterial genomes including mycobacteria, encode for one type I topoisomerase and a DNA gyrase. Here we describe a new type II topoisomerase from Mycobacterium smegmatis which is different from DNA gyrase or topoisomerase IV in its characteristics and origin. The topoisomerase is distinct with respect to domain organization, properties and drug sensitivity. The enzyme catalyses relaxation of negatively supercoiled DNA in an ATP‐dependent manner and also introduces positive supercoils to both relaxed and negatively supercoiled substrates. The genes for this additional topoisomerase are not found in other sequenced mycobacterial genomes and may represent a distant lineage.
Identification of Klebsiella pneumoniae virulence determinants using an intranasal infection model
Authors: Lawlor Matthew S. , Hsu James , Rick Paul D. , Miller Virginia L.
Published: October 2005

Klebsiella pneumoniae is a Gram‐negative enterobacterium that has historically been, and currently remains, a significant cause of human disease. It is a frequent cause of urinary tract infections and pneumonia, and subsequent systemic infections can have mortality rates as high as 60%. Despite its clinical significance, few virulence factors of K. pneumoniae have been identified or characterized. In this study we present a mouse model of acute K. pneumoniae respiratory infection using an intranasal inoculation method, and examine the progression of both pulmonary and systemic disease. Wild‐type infection recapitulates many aspects of clinical disease, including significant bacterial growth in both the trachea and lungs, an inflammatory immune response characterized by dramatic neutrophil influx, and a steady progression to systemic disease with ensuing mortality. These observations are contrasted with an infection by an isogenic capsule‐deficient strain that shows an inability to cause disease in either pulmonary or systemic tissues. The consistency and clinical accuracy of the intranasal mouse model proved to be a useful tool as we conducted a genetic screen to identify novel virulence factors of K. pneumoniae. A total of 4800 independent insertional mutants were evaluated using a signature‐tagged mutagenesis protocol. A total of 106 independent mutants failed to be recovered from either the lungs or spleens of infected mice. Small scale independent infections proved to be helpful as a secondary screening method, as opposed to the more traditional competitive index assay. Those mutants showing verified attenuation contained insertions in loci with a variety of putative functions, including a large number of hypothetical open reading frames. Subsequent experiments support the premise that the central mechanism of K. pneumoniae pathogenesis is the production of a polysaccharide‐rich cell surface that provides protection from the inflammatory response.
SapT, a lanthionine‐containing peptide involved in aerial hyphae formation in the streptomycetes
Authors: Kodani Shinya , Lodato Michael A. , Durrant Marcus C. , Picart Francis , Willey Joanne M.
Published: October 2005

The developmentally complex soil microbe Streptomyces tendae secretes a hydrophobic peptide that restored to developmental mutants of S. coelicolor the ability to raise aerial hyphae. The S. tendae peptide, SapT, has a lantibiotic structure and molecular modelling predicts that it is amphiphilic, making it structurally and functionally similar to the SapB peptide produced by S. coelicolor. However, SapT, which bears three β‐methyl lanthionine bridges and one lanthionine bridge and demonstrated limited antibiotic activity, is distinct from SapB. The amphiphilic nature of both SapT and SapB is required for their ability to serve as biosurfactants facilitating the emergence of newly formed aerial hyphae. Remarkably, SapB and SapT, and the fungal hydrophobin SC3 were shown to restore to a SapB‐deficient S. coelicolor mutant the capacity to undergo complete morphogenesis, such that the extracellular addition of protein resulted in sporulation. This suggests that the initiation of aerial growth may also indirectly trigger the signal transduction events needed for differentiation. These data imply that the production of morphogenetic peptides may be common among the streptomycetes, but that while their ability to function as biosurfactants is conserved, their specific lantibiotic structure is not. Finally, the identification of a second lanthionine‐containing morphogenetic peptide suggests that lantibiotic structure and function may be more diverse than previously thought.
Genetics of resistance to cotton leaf curl disease in Gossypium hirsutum
Authors: Rahman M. , Hussain D. , Malik T. A. , Zafar Y.
Published: October 2005

Twenty‐two cotton varieties were screened for resistance to cotton leaf curl disease (CLCuD), a disease of viral origin, using three procedures: field evaluation, whitefly transmission assay and graft inoculation. Viral infection of cotton varieties was determined by visual symptom assessment as well as dot‐blot and multiplex PCR diagnostic techniques. Crosses were made between the most susceptible variety (S‐12) and highly resistant varieties (CP‐15/2, LRA‐5166 and CIM‐443). All F1 plants of these crosses were resistant, showing dominant expression of the resistance as well as the absence of extrachromosomal inheritance. The F2 plants of the crosses CP‐15/2 × S12, LRA‐5166 × S‐12 and CIM‐443 × S12 exhibited a ratio of 13 resistant (symptomless) to three susceptible (with symptoms). Screening of the F2 generation for virus infection by multiplex PCR further subdivided the resistant class into those exhibiting a high level of resistance (HR; PCR‐negative) and those exhibiting resistance (R; symptomless, yet showing virus replication by PCR analysis). Hence, the final ratio was 3:10:3 (HR:resistant:susceptible). The F3 progeny of susceptible F2 plants segregated for resistance, indicating the probable presence of a suppressor gene (S). These findings are consistent with three genes being involved in G. hirsutum resistance to CLCuD, two for resistance (R1CLCuDhir and R2CLCuDhir) and a suppressor of resistance (SCLCuDhir).
Sequence characterization of four putative membrane‐associated proteins from sweet potato little leaf strain V4 phytoplasma
Authors: Mounsey K. E. , Streten C. , Gibb K. S.
Published: October 2005

To increase understanding of the genetic architecture of phytoplasmas, a random clone (pH80) of the sweet potato little leaf strain‐V4 (SPLL‐V4) phytoplasma and the glucose‐inhibited division protein A (gidA) gene were analysed. Clone pH80 and the gidA gene are located in a 100‐kb region near the putative origin of replication. Three ORFs were identified within the pH80 random clone, encoding the proteins PotB, PotC and PotD, which form part of an ABC transport system for polyamine import. Sequence data were supported by structural analysis which indicated that SPLL‐V4 PotB and PotC were integral membrane proteins, and PotD was a substrate‐binding, surface‐exposed membrane protein. The gidA gene in the SPLL‐V4 phytoplasma was also putatively identified as a membrane protein. The complete gidA gene sequences were characterized for the tomato big bud and SPLL‐V4 phytoplasmas. The proteins identified here were found to share high similarity with those recently identified in the onion yellows phytoplasma genome. Both the gidA and polyamine transport operons are believed to be associated with DNA replication.
Analysis of the histone H3 gene family in Arabidopsis and identification of the male‐gamete‐specific variant AtMGH3
Authors: Okada Takashi , Endo Makoto , Singh Mohan B. , Bhalla Prem L.
Published: October 2005

Histones are major components of chromatin, the protein–DNA complex involved in DNA packaging and transcriptional regulation. Histone genes have been extensively investigated at the genome level in animal systems and have been classified as replication dependent, replication independent or tissue specific. However, no such study is available in a plant system. In this paper we report that there are 15 histone H3 genes in the Arabidopsis genome, including five H3.1 genes, three H3.3 genes and five H3.3‐like genes. A gene structure analysis revealed that gene duplication causes redundancy of the histone H3 genes. The expression of one of the H3 genes, termed AtMGH3/At1g19890, is cell‐specific, being restricted to the generative and sperm cells of Arabidopsis pollen as shown by in situ hybridisation and reporter gene analysis. Thus, we conclude that in Arabidopsis, AtMGH3 is a male‐gamete‐specific histone H3 gene. A T‐DNA insertion line for AtMGH3 revealed decreased expression and ectopic RNA splicing. The T‐DNA insertion lines for AtMGH3/At1g19890 and other H3 genes revealed a normal growth phenotype and reproductive fertility. These findings suggest that other H3 genes are likely to compensate for the T‐DNA‐insertion‐induced loss of a single H3 gene because of the high redundancy of these genes in the Arabidopsis genome. These T‐DNA mutant lines should be useful for accumulating different H3 gene mutations in a single plant and for studying replication‐dependent and replication‐independent H3 genes and the specific role of AtMGH3 in chromatin remodelling and transcriptional regulation during development of male gametes.
Consistent transcriptional silencing of 35S‐driven transgenes in gentian
Authors: Mishiba Kei‐ichiro , Nishihara Masahiro , Nakatsuka Takashi , Abe Yoshiko , Hirano Hiroshi , Yokoi Takahide , Kikuchi Akiko , Yamamura Saburo
Published: October 2005

In this study, no transgenic gentian (Gentiana triflora × Gentiana scabra) plants produced via Agrobacterium‐mediated transformation exhibited transgene (GtMADS, gentian‐derived MADS‐box genes or sGFP, green fluorescent protein) expression in their leaf tissues, despite the use of constitutive Cauliflower mosaic virus (CaMV) 35S promoter. Strikingly, no expression of the selectable marker gene (bar) used for bialaphos selection was observed. To investigate the possible cause of this drastic transgene silencing, methylation‐specific sequences were analysed by bisulfite genomic sequencing using tobacco transformants as a control. Highly methylated cytosine residues of CpG and CpWpG (W contains A or T) sites were distinctively detected in the promoter and 5′ coding regions of the transgenes 35S‐bar and 35S‐GtMADS in all gentian lines analysed. These lines also exhibited various degrees of cytosine methylation in asymmetrical sequences. The methylation frequencies in the other transgene, nopaline synthase (NOS) promoter‐driven nptII, and the endogenous GtMADS gene coding region, were much lower and were variable compared with those in the 35S promoter regions. Transgene methylation was observed in the bialaphos‐selected transgenic calluses expressing the transgenes, and methylation sequences were distributed preferentially around the as‐1 element in the 35S promoter. Calluses derived from leaf tissues of silenced transgenic gentian also exhibited transgene suppression, but expression was recovered by treatment with the methylation inhibitor 5‐aza‐2′‐deoxycytidine (aza‐dC). These results indicated that cytosine methylation occurs exclusively in the 35S promoter regions of the expressed transgenes during selection of gentian transformants, causing transcriptional gene silencing.
Appearance of actin microfilament ‘twin peaks’ in mitosis and their function in cell plate formation, as visualized in tobacco BY‐2 cells expressing GFP–fimbrin
Authors: Sano Toshio , Higaki Takumi , Oda Yoshihisa , Hayashi Tomomi , Hasezawa Seiichiro
Published: October 2005

The actin cytoskeleton of higher plants plays an essential role in plant morphogenesis and in maintaining various cellular activities. In this study we established a tobacco BY‐2 cell line, stably transformed with a GFP–fimbrin actin‐binding domain (ABD) 2 construct, that allows visualization of actin microfilaments (MFs) in living cells. Using this cell line, designated BY‐GF11, we performed time‐sequential observations of MF dynamics during cell‐cycle progression. Detailed analyses revealed the appearance of a broad MF band in the late G2 phase that separated to form a structure corresponding to the so‐called actin‐depleted zone (ADZ) in mitosis. In BY‐GF11, the MF structure at the cell cortex in mitosis appeared to form two bands rather than the ADZ. Measurements of fluorescent intensities of the cell cortex indicated an MF distribution that resembled two peaks, and we therefore named the structure MF ‘twin peaks’ (MFTP). The cell plate formed exactly within the valley between the MFTP at cytokinesis, and this cell‐plate guidance was distorted by disruption of the MFTP by an inhibitor of actin polymerization. These results suggest that the MFTP originates from the broad MF band in the G2 phase and functions as a marker of cytokinesis.
Overexpression of a GRAS protein lacking the DELLA domain confers altered gibberellin responses in rice
Authors: Itoh Hironori , Shimada Asako , Ueguchi‐Tanaka Miyako , Kamiya Noriko , Hasegawa Yasuko , Ashikari Motoyuki , Matsuoka Makoto
Published: October 2005

The rice SLR1 (SLENDER RICE 1) gene encodes a DELLA protein that belongs to a subfamily of the GRAS protein superfamily and that functions as a repressor of gibberellin (GA) signaling. Based on the constitutive GA response phenotype of slr1 mutants, SLR1 has been thought to be the sole DELLA‐type protein suppressing GA signals in rice. However, in rice genome databases we identified two sequences homologous to SLR1: SLR1‐like1 and ‐2 (SLRL1 and ‐2). SLRL1 and SLRL2 contain regions with high similarity to the C‐terminal conserved domains in SLR1, but lack the N‐terminal conserved region of the DELLA proteins. The expression of SLRL1 was positively regulated by GA at the mRNA level and occurred preferentially in reproductive organs, whereas SLRL2 was moderately expressed in mature leaf organs and was not affected by GA. Transformation of SLRL1 into the slr1 mutant rescued the slender phenotype of this mutant. Moreover, overexpression of SLRL1 in normal rice plants induced a dwarf phenotype with an increased level of OsGA20ox2 gene expression and diminished the GA‐induced shoot elongation, suggesting that SLRL1 acts as a repressor of GA signaling. Consistent with the fact that SLRL1 does not have a DELLA domain, which is essential for degradation of DELLA proteins, a level of SLRL1 protein was not degraded by application of gibberellic acid. However, the repressive activity of SLRL1 against GA signaling was much weaker than a truncated SLR1 lacking the DELLA domain. Based on these characteristics of SLRL1, the functional roles of SLRL1 in GA signaling in rice are discussed.
Split Hand Foot Malformation (SHFM)
Authors: Elliott AM , Evans JA , Chudley AE
Published: October 2005

The nomenclature describing the phenotype of missing central rays in the hand and/or foot in the genetics and surgical literature is heterogeneous and confusing. Split hand/foot malformation (SHFM) is the most common term for this phenotype in the genetics community; however, other names such as the offensive ‘lobster‐claw malformation’ and the non‐specific ‘ectrodactyly’ are still utilized to describe this malformation. In this article, we briefly review the nomenclature associated with SHFM and its classifications.
HLA‐A and HLA‐B allele frequencies in a mestizo population from Guadalajara, Mexico, determined by sequence‐based typing
Authors: Leal C. A. , Mendoza‐Carrera F. , Rivas F. , Rodriguez‐Reynoso S. , Portilla‐de Buen E.
Published: October 2005

HLA‐A and HLA‐B genes were typed by DNA sequencing in a mestizo population from Guadalajara, Jalisco, Mexico. Thirty‐seven HLA‐A and 51 HLA‐B alleles were observed in 103 samples. The common typical Amerindian alleles (>5%) and haplotypes (≥2.0%) found were A*02010101, *24020101, *310102, B*350101, and *4002, and A*310102‐B*4002, A*240201‐B*350101, and the typical European alleles were A*010101, *29010101, B*1402, B*180101, and A*020101‐B*1402, A*020101‐B*510101, and A*3002‐B*180101. This reflects the blending of the two main parental populations of mestizos: Amerindian and Iberian. Mexicans were found to be relatively closer to the Portuguese than to Spaniards. This proximity may indicate a larger Portuguese influence in Mexicans than previously considered. Present data contribute to the understanding of the genetic structure in Mexico.
A searchable database for proteomes of oral microorganisms
Authors: Nakano Y. , Shibata Y. , Kawada M. , Kojima M. , Fukamachi H. , Shibata Y. , Okano S. , Matsushima K. , Abiko Y. , Yamashita Y.
Published: October 2005

An online database of proteomes for two‐dimensional electrophoresis (2DE) gel data was constructed and it is now freely accessible through a web‐based interface. Proteins from three oral bacteria, Streptococcus mutans UA159, Actinobacillus actinomycetemcomitans HK1651, and Porphyromonas gingivalis W83, whose genome databases are freely available, were separated by 2DE, and protein spots were analyzed by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) and identified. About 1000 spots from the gels of P. gingivalis W83 were extracted and analyzed by MALDI‐TOF, and 330 proteins were identified. In addition, 160 of 240 spots of A. actinomycetemcomitans and 158 of 356 spots of S. mutans were identified. Information such as spot coordinates on the gels, protein names (predicted functions), molecular weights, isoelectroric points, and links to online databases, including Oral Pathogen Sequence Databases of the Los Alamos National Laboratory Bioscience Division (ORALGEN) and National Center for Biotechnology Information (NCBI) or The Institute Genomic Research (TIGR), were stored in tables accessible through the relational database management system MySQL on an Apache web server. To test for functionality of this database system, responses of S. mutans to environmental changes were analyzed using the database and 21 spots on the gel were identified as proteins whose expression had been increased or decreased by environmental pH change without in‐gel trypsin digestion, protein extraction, or MALDI‐TOF/TOF‐MS (mass spectrometer) analysis. The identified proteins are agreement with those reported in previous papers on acid tolerance of S. mutans, demonstrating the usefulness of the system. This database is available at http://www.myamagu.dent.kyushu‐u.ac.jp/~bioinformatics/index.html or http://www.bipos.mascat.nihon‐u.ac.jp/index.html.
Occurrence of two newly named oral treponemes –Treponema parvum and Treponema putidum– in primary endodontic infections
Authors: Rôças I. N. , Siqueira J. F.
Published: October 2005

Background/aims:  Recent evidence from molecular genetic studies has revealed that oral Treponema species are involved in infections of endodontic origin. This study assessed the occurrence of two newly named oral treponemes − Treponema parvum and Treponema putidum – in primary endodontic infections using a culture‐independent identification technique.

Methods:  Genomic DNA was isolated directly from clinical samples, and a 16S rRNA gene‐based nested polymerase chain reaction (PCR) assay was used to determine the presence of T. parvum and T. putidum. Species‐specific primer pairs were developed by aligning closely related 16S rRNA gene sequences. The specificity for each primer pair was validated by running PCR against a panel of oral bacteria and by sequence analysis of PCR products from positive clinical samples.

Results:  T. parvum was detected in 52% of the root canals associated with chronic apical periodontitis, in 20% of the cases diagnosed as acute apical periodontitis, and in no abscessed case. In general, T. parvum was detected in 26% of the samples from primary endodontic infections. T. putidum was found in only one case of acute apical periodontitis (2% of the total number of cases investigated).

Conclusions:  The devised nested PCR protocol was able to identify both T. parvum and T. putidum directly in clinical samples and demonstrated that these two treponemes can take part in endodontic infections.
Gene expression analysis of the CD4+ T‐cell clones derived from gingival tissues of periodontitis patients
Authors: Ito H. , Honda T. , Domon H. , Oda T. , Okui T. , Amanuma R. , Nakajima T. , Yamazaki K.
Published: October 2005

The function of T cells infiltrating periodontitis lesions is complex and has not been fully elucidated. Here, we established T‐cell clones from the gingival tissues of periodontitis patients and examined their gene expression. A total of 57 and 101 T‐cell clones were established by means of immobilized anti‐CD3 antibody and IL‐2 from gingival tissues and peripheral blood, respectively. The gingival T‐cell clones were derived from three patients, and the peripheral blood T‐cell clones from two of these patients and a further patient whose gingival T‐cell clones were not established. Gingival tissues were also obtained from a further 19 periodontitis patients. The expression of cytokines and molecules related to both regulatory function and tissue destruction were examined by means of reverse‐transcription polymerase chain reaction. All the gingival T‐cell clones expressed mRNA for TGF‐β1, CTLA‐4, and CD25, and all the T‐cell clones from peripheral blood expressed IFN‐γ and TGF‐β1 mRNAs. Most but not all the T‐cell clones from gingival tissues and peripheral blood expressed mRNA for IFN‐γ and, CD25 and CTLA‐4, respectively. The frequency of T‐cell clones and gingival tissues expressing FOXP3, a possible master gene for mouse CD4+CD25+ regulatory T cells, was very high (97%, 93%, and 100% for gingival T‐cell clones, peripheral blood T‐cell clones, and gingival tissues, respectively). Whereas the frequency of IL‐4‐expressing T‐cell clones was lower for gingival T‐cell clones (70% vs. 87%), the frequency of the gingival T‐cell clones expressing IL‐10 and IL‐17 was higher than peripheral blood T‐cell clones (75% vs. 62% for IL‐10, 51% vs. 11% for IL‐17). A similar expression profile was observed for gingival T‐cell clones compared with gingival tissue samples with the exception of IL‐4 expression, where the frequency of positive samples was lower in the gingival tissues (70% vs. 11%). These results suggest that the individual T cells infiltrating gingival lesions can express mRNA for both Th1 and Th2 cytokines as well as regulatory cytokines simultaneously.
Involvement of antigen I/II surface proteins in Streptococcus mutans and Streptococcus intermedius biofilm formation
Authors: Pecharki D. , Petersen F. C. , Assev S. , Scheie A. A.
Published: October 2005

Background/aim:  Dental diseases are caused by microorganisms organized in biofilms. Streptococcus mutans and Streptococcus intermedius are commensals of the human oral cavity. S. mutans is associated with caries, whereas S. intermedius is associated with purulent infections. Oral streptococci including S. mutants and S. intermedius express a family of surface proteins termed antigen I/II (Ag I/II). Ag I/II is implicated in adhesion; however, its role in biofilm formation has not yet been investigated.

Methods:  By using isogenic Ag I/II‐deficient mutants of S. mutans and S. intermedius we studied the influence of Ag I/II on in vitro biofilm formation. Biofilm was quantified in polystyrene microtiter plates and visualized by scanning electron microscopy. Ag I/II expression in planktonic and biofilm cells, as well as in the presence or absence of saliva was investigated by immunoblotting.

Results:  In the presence of saliva, the Ag I/II‐deficient mutants formed 65% less biofilm than the wild‐types. In the absence of saliva, no difference was observed in S. mutans, whereas the S. intermedius Ag I/II mutant formed 41% less biofilm. Ag I/II expression was reduced in the presence of saliva. No differences in expression were observed between biofilm and planktonic cells.

Conclusion:  The results indicated that Ag I/II may be important during biofilm formation particularly in the presence of saliva. These findings may provide useful information regarding the importance of Ag I/II in biofilm formation and in the search of new strategies to control biofilm‐mediated infections.
Outcome of pediatric liver transplant recipients in Turkey: Single center experience
Authors: Aydogdu S. , Arikan C. , Kilic M. , Ozgenc F. , Akman S. , Unal F. , Yagci R. V. , Tokat Y.
Published: October 2005

Abstract:  To summarize the evolution of the pediatric liver transplant program in a developing country. Between April 1997, and September 2003, 32 cadaveric (CD) and 35 living donor (LD) liver transplantations were performed on 61 children (median age 3.8 yr, range 0.5–16) at Ege University Organ Transplantation and Research Center. The patient's charts were reviewed retrospectively. The outcome of patient and graft survival was analyzed and the incidence of graft loss, complications and rejections was calculated. Indications for liver transplantation were metabolic liver disease (n = 17), biliary atresia (n = 14), viral hepatitis (n = 4), autoimmune hepatitis (n = 6), cryptogenic cirrhosis (n = 11), fulminant liver failure (n = 5) and others (n = 5). Seven of 61 children with chronic liver disease had hepatocellular carcinoma concomitantly. Median pediatric end‐stage liver disease score was 23 (range 1–54). Seven children (11.4%) were UNOS status I, 44 (72%) were UNOS status II and 10 (16.6%) were UNOS status III. The median follow‐up of the study population was 3.6 yr (range 0.5–6). Actuarial patient survival rates at 1, 2, 3 and 4 yr were 86, 86, 71.3 and 65% in the CD group vs. 80, 76, 67 and 67% in the LR group, respectively (p = NS). Patients listed as UNOS status 1 had lower survival rates than patients listed as UNOS status 2 and 3 (p < 0.05). The mortality rate was 26.2%. Graft survival rates were 81, 81, 75 and 64% at 1, 2, 3 and 4‐yr respectively. Six patients (9%) underwent retransplantation. The main complications were infections (64.7%) and surgical complications (43.2%) (including biliary complication, vascular problems, postoperative bleeding, small for size and large for size). The incidence of acute cellular rejection was 39.3%, whereas chronic rejection was 7.4%. The result of liver transplantation in Turkish children was slightly inferior to those reported for North American and European children. However, an important characteristic of these patients that distinguishes them from Europe and North America is that most were UNOS status IIa and UNOS status I (44%). Despite technical and medical progress, infectious and biliary problems have continued to be an important cause of mortality in these patients.
Three consecutive related bone marrow transplants for juvenile myelomonocytic leukaemia
Authors: Faraci Maura , Micalizzi Concetta , Lanino Edoardo , Scuderi Francesca , Morreale Giuseppe , Dini Giorgio , Cappelli Barbara , Dallorso Sandro
Published: October 2005

Abstract:  Allogeneic haematopoietic stem cell transplantation (allo‐HSCT) is the only cure for juvenile myelomonocytic leukaemia (JMML), but relapse remains the major cause of failure. A second transplant may be considered a way to induce the graft vs. leukaemia effect in patients who relapse after their first HSCT. We describe a 7‐month‐old girl with JMML who relapsed after a first, related allo‐HSCT, and who again relapsed 8 months after the second transplant, despite discontinuation of immusuppressive therapy. She underwent a third allogeneic transplant from another related donor. At the time of this report the patient is in complete remission 26 months after the third transplant. We suggest that a third allo‐HSCT may be taken into consideration for JMML patients who experience relapse, even after two previous transplants.
Better renal function with enhanced immunosuppression and protocol biopsies after kidney transplantation in children
Authors: Seikku Paula , Krogerus Leena , Jalanko Hannu , Holmberg Christer
Published: October 2005

Abstract:  Subclinical rejection may be associated with decreased graft function after renal transplantation (Tx). Detection by protocol biopsies and treatment could thus be important for the long‐term prognosis. We have earlier discovered that glomerular filtration rate (GFR) declined in young children during the first 18 months. Consequently, we slightly enhanced and individualized each patient's immunosuppression. This was a retrospective study of 59 pediatric renal Tx patients between 1995 and 2001. The 35 historical controls received triple‐therapy of azathioprine, methylprednisolone and cyclosporine. GFR was measured by protocol at discharge, 6 and 18 months, and a core biopsy was obtained at 18 months. The 24 study patients in addition received basiliximab, had GFR measured at 3 and 12 months, and a biopsy taken at 3 months. Based on histology and function, immunosuppression was individually adjusted. The groups were compared for GFR and histology at 18 months after Tx. There were less acute rejection episodes in the study group (0.38 vs. 1.23 per patient) and serum creatinine concentrations were lower. Subclinical rejection was detected and treated in 39% at 3 months. There were more chronic changes in the control (47%) than in the study group (29%) at 18 months. GFR was significantly higher in the study group at 18 months (87 vs. 68 mL/min/1.73 m2), most remarkably in patients ≤2 yr of age (99 vs. 68 mL/min/1.73 m2). Detection of subclinical rejection and slightly enhanced and individualized immunosuppression improved GFR 18 months after renal Tx, especially in the youngest patients.
Determinants of graft survival in pediatric and adolescent live donor kidney transplant recipients: A single center experience
Authors: El‐Husseini Amr A. , Foda Mohamed A. , Shokeir Ahmed A. , Shehab El‐Din Ahmed B. , Sobh Mohamed A. , Ghoneim Mohamed A.
Published: October 2005

Abstract:  To study the independent determinants of graft survival among pediatric and adolescent live donor kidney transplant recipients. Between March 1976 and March 2004, 1600 live donor kidney transplants were carried out in our center. Of them 284 were 20 yr old or younger (mean age 13.1 yr, ranging from 5 to 20 yr). Evaluation of the possible variables that may affect graft survival were carried out using univariate and multivariate analyses. Studied factors included age, gender, relation between donor and recipient, original kidney disease, ABO blood group, pretransplant blood transfusion, human leukocyte antigen (HLA) matching, pretransplant dialysis, height standard deviation score (SDS), pretransplant hypertension, cold ischemia time, number of renal arteries, ureteral anastomosis, time to diuresis, time of transplantation, occurrence of acute tubular necrosis (ATN), primary and secondary immunosuppression, total dose of steroids in the first 3 months, development of acute rejection and post‐transplant hypertension. Using univariate analysis, the significant predictors for graft survival were HLA matching, type of primary urinary recontinuity, time to diuresis, ATN, acute rejection and post‐transplant hypertension. The multivariate analysis restricted the significance to acute rejection and post‐transplant hypertension. The independent determinants of graft survival in live‐donor pediatric and adolescent renal transplant recipients are acute rejection and post‐transplant hypertension.
Pediatric obesity at renal transplantation: A single center experience
Authors: Omoloja Abiodun , Stolfi Adrienne , Mitsnefes Mark
Published: October 2005

Abstract:  Obesity is a major issue affecting health care delivery. While studies have been done in adults with end‐stage renal disease, similar studies are lacking in pediatric patients with this disease. We retrospectively analyzed our renal transplant database from 1978 to 2002, to identify prevalence and predisposing factors to obesity in a pediatric end‐stage renal disease population. Obesity, particularly in younger individuals, was found to be prevalent at transplantation.