bluuebunny/crossref_metadata_2025 huggingface dataset:
Real‐time image enhancement of television for the visually impaired – pilot study
Authors: Wolffsohn James S
Published: February 2006

Purpose:  To determine whether a universal image enhancement could be conducted in real‐time to enhance the viewing clarity of television images by the visually impaired.

Method:  One minute clips of television news and advert footage were digitally captured and converted to AVI format. These were displayed to five subjects with low vision (<0.5 logMAR binocular visual acuity) at the same time as a real‐time image of the edges detected (white on black image) and the original colour image overlaid by the detected edges coloured in red.

Results:  Forced choice comparison resulted in the image enhanced colour image being preferred over the original and edges only image for both video clips in all subjects. This image analysis could be performed on a live television image and displayed at 25 Hz (PAL format).

Conclusion:  Current technology allows real‐time image enhancement of television images and a universal edge enhancement overlaid on the original footage appears to benefit the visually impaired. If larger trials support this finding, it is envisaged that a small signal processing box could be connected to a television to enhance the viewing clarity for the visually impaired.
Detecting clinical change using visual acuity measurements – the effect of uncorrected refractive error
Authors: Rosser Dan
Published: February 2006

It is well known that when visual acuity is measured repeatedly, the resultant acuity score tends to vary even in the absence of true clinical change. The greater the degree of test‐retest variability (TRV), the larger a genuine change in clinical status must be before it can be reliably detected using visual acuity data alone. TRV may be reduced by using charts based upon rigorous design principles, and/or employing interpolated scoring methods. A review of published estimates of TRV suggested that the presence of uncorrected refractive error may increase TRV. A study was designed to assess the effect of varying degrees of optical defocus upon the TRV of ETDRS logMAR visual acuity measurements in normal subjects. Estimates of TRV were ±0.10 log MAR for zero defocus, ±0.18 log MAR for +0.50 D defocus, and ±0.24 log MAR for +1.00 D defocus (p = 0.0002). These results suggest that even small degrees of uncorrected refractive error may have a dramatic affect upon the TRV of visual acuity measurements. This finding may have considerable implications for the detection of clinical change in individuals, as well as the design of clinical trials which use visual acuity data as a primary outcome variable.

Reference:  Rosser, D. A., Murdoch, I. E. and Cousens S. N. (2004) The effect of optical defocus on the test‐retest variability of visual acuity measurements. Invest Ophthalmol Vis Sci45, 1076–1079.
Thirty years in the life of the Moorfields Eye Hospital Low Vision clinic
Authors: Crossland Michael
Published: February 2006

Purpose:  The Moorfields Low Vision Clinic is thought to be the largest in the world. This presentation will provide a historical perspective of the work performed in the low vision clinic, based on a retrospective review of entries made in the clinic's summary ledger between 1973 and 2003.

Methods:  Data were collected from the ledger for all patients attending the low vision clinic during the month of June in 1973, 1978, 1983, 1988, 1993, 1998 and 2003. Demographic data and the type of low vision devices (LVDs) prescribed to newly attending patients were recorded.

Results:  1438 patient visits were identified, of which 40% were first attendances. The median age, proportion of patients over 60 and sex distribution of the patients did not alter significantly over time. The most frequently prescribed devices were non‐illuminated hand magnifiers, illuminated hand magnifiers and illuminated stand magnifiers. There was a linear increase in the proportion of hand magnifiers prescribed between 1973 and 2003 (r2 = 0.62, p < 0.05) and a corresponding decrease in the number of near spectacle‐mounted telescopes prescribed (r2 = 0.70, p < 0.05).

Conclusions:  Between 1973 and 2003, the low vision clinic at Moorfields Eye Hospital provided nearly 100 000 low vision consultations. The demographics of patients attending the clinic remained remarkably constant over this time. The number of spectacle‐mounted devices prescribed fell between 1973 and 2003. It is thought this is due in part to the increased availability of electronic magnification devices, and the development of illuminated hand magnifiers. The development of the acrylic bright field magnifier and LED illuminated LVDs have had particular clinical impact.

Reference:  Crossland, M.D. and Silver, J.H. (2005) Thirty years in an urban low vision clinic: changes in prescribing habits of low vision practitioners. Optom Vis Sci82, 617–622.
Clinical negligence
Authors: Woodward E. G.
Published: February 2006

Purpose:  In an increasingly litigious society a growing number of optometrists are being arraigned in the civil courts and by the Disciplinary Committee of the General Optical Council for clinical negligence. This study analysed the main grounds for these charges and considered future implications.

Methods:  50 cases where optometrists were either defendants in a civil court or appearing before the GOC Disciplinary Committee and where the author had provided an expert witness report were examined. These cases occurred between 1999 and 2004. The author was instructed in 19 cases by solicitors acting for the defendant and in 31 cases by the claimants’ solicitors.

Results:  The most frequent complaint was failing to detect glaucoma (15 cases), followed by failure to detect retinal detachments (13). Five of the glaucoma cases were relatively young contact lens wearers (40–60 years of age). There were six cases where failure to detect papilloedema was alleged and in every case the patients were young adults or children with migrainous symptoms referred to the optometrist for refraction. Of the five cases involving ocular neoplasms, four were choroidal melanomas all of which were eventually detected by a second optometrist. In the fifth case, where a melanoma of the iris was not detected the optometrist did record some changes and a difference in IOP between the two eyes, but took no action. In all, 12 different ocular and systemic conditions were the cause of civil litigation or disciplinary proceedings.

Conclusion:  The two most frequent charges against optometrists related to the glaucomas and retinal detachment, and optometrists must practice ‘defensive optometry’ in every case where these might be a possibility. The number of cases relating to intra‐cranial neoplasms was surprising, as an optometrist has no legal obligation to diagnose such conditions. However, they are obliged to detect any consequent papilloedema and this was the issue in every case. Also, in the last few years there has been a tendency to sue both the general medical practitioner and the optometrist in such cases. This occurred in all six of the cases in this series and also in the one case involving diabetic retinopathy. With an increasing role for the optometrist in primary health care more optometrists are liable to find themselves as co‐defendants in actions for clinical negligence.
New chromosome abnormalities and lack of BCL‐6 gene rearrangements in Argentinean diffuse large B‐cell lymphomas
Authors: Cerretini Roxana , Noriega Maria F. , Narbaitz Marina , Slavutsky Irma
Published: February 2006

Abstract:  Objectives: Diffuse large B‐cell lymphoma (DLBCL) is the most common form of non‐Hodgkin lymphomas. Cytogenetic studies have revealed a broad spectrum of clonal genetic abnormalities and complex karyotypes. The purpose of this study was to contribute to the understanding of the genomic alterations associated with this group of lymphomas. Methods: Cytogenetic, fluorescence in situ hybridization (FISH) and molecular analyses were performed in 30 cases with DLBCL: 20 de novo DLBCL (dn‐DLBCL) and 10 DLBCL secondary to follicular lymphoma (S‐DLBCL). Results: A total of 37 different structural chromosomal rearrangements were found: 27% translocations, 54% deletions, and 19% other alterations. Chromosomes 8, 6, 2, and 9 were the most commonly affected. Interestingly, translocation t(3;14)(q27;q32) and/or BCL‐6 gene rearrangements were not observed either by cytogenetic studies or by FISH analysis. Fifteen novel cytogenetic alterations were detected, among them translocations t(2;21)(p11;q22) and t(8;18)(q24;p11.3) appeared as sole structural abnormalities. Translocation t(14;18)(q32;q21) and/or BCL‐2‐IGH gene rearrangements were the genomic alterations most frequently observed: 50% of S‐DLBCL and 30% of dn‐DLBCL. Deletions del(4)(q21), del(6)(q27), del(8)(q11), and del(9)(q11) were recurrent. The most common gains involved chromosome regions at 12q13‐q24, 7q10‐q32, and 17q22‐qter; 6q was the most frequently deleted region, followed by losses at 2q35‐qter, 7q32‐qter, and 9q13‐qter. Four novel regions of loss were identified: 5q13‐q21, 2q35‐qter (both recurrent in our series), 4p11‐p12, and 17q11‐q12. Conclusions: These studies emphasize the value of combining conventional cytogenetics with FISH and molecular studies to allow a more accurate definition of the genomic aberrations involved in DLBCL.
ZAP‐70 mRNA quantification in B‐cell chronic lymphocytic leukaemia
Authors: Catherwood Mark A. , Matthews Christine , Niblock Roberta , Dobbin Edwina , Morris T. C. M. , Denis Alexander H.
Published: February 2006

Abstract:  Objective: The mutational status of the immunoglobulin (Ig) VH gene in B‐cell chronic lymphocytic leukaemia (B‐CLL) identifies two subgroups of patients with significantly different outcomes. We investigated the association of ZAP‐70 expression with IgVH mutational status in B‐CLL by quantifying ZAP‐70 mRNA, to evaluate its use as a surrogate marker for mutational status. The aim of this study was to develop a quantitative reverse transcriptase‐polymerase chain reaction (RQ‐PCR) assay for the detection of ZAP‐70 expression in a group of patients whose mutational status and cytogenetics had been determined previously. Methods: RQ‐PCR was used to analyse ZAP‐70 expression from 42 B‐CLL patients. B cells were purified using CD19 magnetic bead system and total RNA was isolated. RQ‐PCR was performed using Taqman PCR. Results: Twenty‐five patients (60%) had mutated and 17 (40%) had unmutated IgVH genes; 94% (16/17) of patients with unmutated IgVH gene were ZAP‐70 positive as assessed by RQ‐PCR and 92% (23/25) of patients with mutated IgVH gene were ZAP‐70 negative. In three patients, ZAP‐70 expression and IgVH mutational status were discordant. Conclusion: This paper describes an RQ‐PCR assay for the detection of ZAP‐70 expression and confirms that IgVH unmutated CLL cells have a high expression of ZAP‐70 in comparison with IgVH mutated CLL. This robust method acts as a surrogate marker for IgVH mutational status albeit with <100% concordance. However, it does provide better concordance with mutational status than that reported using flow cytometry.
Antiphospholipid antibodies may be a new prognostic parameter in aggressive non‐Hodgkin's lymphoma
Authors: Bairey Osnat , Blickstein Dorit , Monselise Yehudit , Lahav Judith , Stark Pinhas , Prokocimer Miron , Nativ Hila Magen , Kirgner Ilia , Pazgal Idit , Shaklai Mati
Published: February 2006

Abstract:  Objectives: Patients with malignancies have an increased prevalence of antiphospholipid antibodies (APA). The aim of this study was to determine the prevalence of IgG, IgM, and IgA anticardiolipin antibodies (aCL) and anti‐beta‐2 glycoprotein I antibodies (anti‐β2‐GPI) in patients with non‐Hodgkin's lymphoma (NHL), and to investigate their clinical and prognostic significance. Methods: The study group included 86 patients with NHL. Enzyme‐linked immunosorbent assay kits were used to measure the concentrations of aCL and anti‐β2‐GPI, and coagulation tests, to measure lupus anticoagulant (LAC) activity. Blood was collected at diagnosis in all patients and at follow‐up in 15. Median follow‐up time was 1.9 yr. Results: Elevated APA levels were found in 35 patients (41%) at diagnosis: one patient aCL IgG, five patients aCL IgM, five aCL IgA, one anti‐β2‐GPI IgG, 14 anti‐β2‐GPI IgM, and 19 anti‐β2‐GPI IgA; LAC activity was found in three of 67 patients (4.5%). There was no significant correlation between elevated APA levels and patient's age or sex, disease stage or grade, bone marrow involvement, B symptoms, serum lactate dehydrogenase levels, serum β2 microglobulin levels, International Prognostic Index (IPI) score, performance status, type of treatment, or response to treatment. There was a correlation between elevated APA and absence of extranodal disease (P = 0.045). A strong negative correlation was found between elevated APA at diagnosis and survival time. Two‐year survival was 90 ± 5% for patients without APA at diagnosis compared with 63 ± 11% for patients with an elevated APA levels (P = 0.0025). APA added to the predictive value of IPI for event‐free and overall survival. Conclusions: APA are elevated in 41% of NHL patients at diagnosis and are correlated with shortened survival. Their level may serve as an independent prognostic variable in aggressive NHL.
Incidence and clinical significance of anti‐PF4/heparin antibodies of the IgG, IgM, and IgA class in 755 consecutive patient samples referred for diagnostic testing for heparin‐induced thrombocytopenia
Authors: Juhl David , Eichler Petra , Lubenow Norbert , Strobel Ulrike , Wessel Antje , Greinacher Andreas
Published: February 2006

Abstract:  Background: Heparin‐induced thrombocytopenia (HIT) is usually caused by anti‐platelet factor 4 (PF4)/heparin antibodies, leading to intravascular platelet activation. These antibodies can be detected by PF4/polyanion antigen assays or platelet activation assays. While antigen assays are very sensitive and recognize immunoglobulin (Ig)G, IgA, and IgM antibodies, the role of IgM and IgA HIT‐antibodies is debated. Platelet activation assays recognize IgG and are more specific for clinical HIT. Methods: We analyzed sera from 755 consecutive patients referred for diagnostic testing for HIT using a PF4/heparin enzyme‐linked immunosorbent assay (ELISA) for IgG, IgA, and IgM and by the heparin‐induced platelet activation (HIPA) test. Clinical information was provided by the treating physicians. Results: A total of 108 of 755 (14.3%) patients tested positive, 105 (13.9%) in the PF4/heparin IgG/A/M ELISA [28 (26.7%) only for IgM/A]; 53 (7.0%) sera were positive in the HIPA, of those 50 tested also positive in the ELISA. In 77 patients sufficient clinical information was provided. Available clinical information for 17 of the 28 patients who had only IgM and/or IgA detected showed plausible alternative (non‐HIT) explanations in four of seven who had thromboembolic complications and in nine of 10 who had isolated HIT. Conclusion: Detection of IgG, IgM and IgA class antibodies by PF4/heparin ELISA yields a positive test result about twice as often as does a platelet activation assay, with only a minority of the additional patients detected likely having HIT. Thus, there is a potential for considerable over‐diagnosis of HIT by laboratories that utilize only an ELISA for diagnostic testing.
Differences between single‐ and dual‐species biofilms of Streptococcus mutans and Veillonella parvula in growth, acidogenicity and susceptibility to chlorhexidine
Authors: Kara Duygu , Luppens Suzanne B. I. , ten Cate Jacob M.
Published: February 2006

Streptococcus mutans, considered a primary pathogen in dental caries, thrives in dental plaque, which is a multispecies biofilm. Metabolic interactions between S. mutans and Veillonella parvula have been suggested. In this study we developed a biofilm model to quantify single‐species (S. mutans or V. parvula) and dual‐species (S. mutans and V. parvula) biofilm formation, and we identified the differences between the respective biofilms in terms of growth, acid formation, and response to chlorhexidine. Polystyrene 96‐well microtiter plates were used for biofilm formation. These biofilms were exposed to various chlorhexidine concentrations (0.025–0.4 mg ml−1) and treatment conditions. Growth of the biofilms and the effects of chlorhexidine were evaluated by viable counts. Viability of the two species in all biofilm types was similar (≈ 108 colony‐forming units per well) after 72 h. Lactic acid accumulation of dual‐species biofilms was significantly lower at 48 and 72 h than single‐species biofilms of S. mutans. Dual‐species biofilms were less susceptible to chlorhexidine than single‐species biofilms when a neutralization step was included. These results indicate that bacteria in dual‐species biofilms have different properties from bacteria in single‐species biofilms.
Photosensitization of in vitro biofilms by toluidine blue O combined with a light‐emitting diode
Authors: Zanin Iriana C. J. , Lobo Maristela M. , Rodrigues Lidiany K. A. , Pimenta Luiz A. F. , Höfling José F. , Gonçalves Reginaldo B.
Published: February 2006

In natural ecosystems, micro‐organisms grow preferentially attached to surfaces, forming matrix‐enclosed biofilms. The aim of this study was to determine photodestruction levels in biofilms after subjecting them to photodynamic therapy. Biofilms of Streptococcus mutans, S. sobrinus, and S. sanguinis were grown on enamel slabs for 3, 5 or 7 d. Both the number of viable micro‐organisms and the concentration of water‐insoluble polysaccharides were analysed, and mineral loss (ΔZ) analyses were performed on the enamel slabs. The antimicrobial potential of toluidine blue O (0.1 mg ml−1), associated with 85.7 J cm−2 of a light‐emission diode, was evaluated on the viability of 5‐d biofilms. Both the number of micro‐organisms and the concentration of water‐insoluble polysaccharide increased with the age of the biofilms. A significant reduction (≈ 95%) in viability was observed for S. mutans and S. sobrinus biofilms following photosensitization, with a > 99.9% reduction in the viability of S. sanguinis biofilms. In conclusion, a biofilm model was shown to be suitable for studying changes in bacterial numbers and enamel mineralization and for demonstrating the potential value of photosensitization in the control of in vitro biofilms.
Fluoride's effect on human dentin ultrasound velocity (elastic modulus) and tubule size
Authors: Vieira Anya P. G. F. , Hancock Ron , Dumitriu Mircea , Limeback Hardy , Grynpas Marc D.
Published: February 2006

Despite fluoride (F) use in caries prevention, not much is known about its effects on tooth quality. This study evaluated the effect of tooth F concentration ([F]) on selected dentin structural and mechanical properties. Third molars (n = 136) from Toronto, which has 1 part per million (p.p.m.) water [F], Montreal (0.2 p.p.m. water [F]), and Fortaleza (Brazil) (0.7 p.p.m. water [F]), were analyzed for [F], dental fluorosis (DF) severity, ultrasound velocity, and dentin tubule size and density. The enamel [F] was found to vary between 32 and 940 p.p.m., the dentin [F] was found to vary between 110 and 860 p.p.m., while the DF severity varied between TF0 and TF4. The enamel [F] showed no correlation with dentin [F], DF severity, ultrasound velocity, dentin tubule size or density. The dentin [F] correlated with DF severity, dentin tubule size, and ultrasound velocity. DF severity showed a correlation with dentin [F] and ultrasound velocity. It was concluded that dentin [F] is an indicator of dentin structural properties (dentin tubule size and ultrasound velocity), while DF severity is an indicator of dentin mechanical properties (ultrasound velocity).
Mechanical behavior of bovine periodontal ligament under tension‐compression cyclic displacements
Authors: Shibata Tatsuya , Botsis John , Bergomi Marzio , Mellal Aissa , Komatsu Koichiro
Published: February 2006

In the present study, the mechanical response of bovine periodontal ligament (PDL) subjected to displacement‐controlled tension–compression harmonic oscillations and subsequent rupture was examined. Specimens including dentine, cementum, PDL, and alveolar bone were extracted from different depths and locations of bovine first molars. They were immersed in a saline solution at room temperature and clamped on their bone and dentine extremities. The samples were tested at ±35% of the PDL's width, with a frequency of 1 Hz. The mechanical parameters evaluated were hysteresis, phase lag, and the modulus of the stress–stretch ratio curves in tension and compression. The tensile strength and the corresponding stretch ratio were also recorded. Stress–stretch ratio curves indicated a non‐linear, time‐dependent response with hysteresis and preconditioning effects. The hysteresis and phase lag in compression were much higher than in tension, suggesting that the dissipated energy was higher in compression than in tension. The root depth and location did not play essential roles for the tension or compression data, with the exception of limited statistical differences for tensile strength and corresponding stretch ratio. Thus, biological variability in the specimens, as a result of different bone contours, PDL width, and fiber orientation, did not affect the energy‐absorbing capacity of the PDL. The evolution of the stress rate with stress demonstrated a constant increase of stiffness with stress. The stiffness values were twofold higher in tension than in compression. The data also showed that the stiffness of the PDL was comparable with data reported for other soft tissues.
Substitution of bovine dentine sialoprotein with chondroitin sulfate glycosaminoglycan chains
Authors: Sugars Rachael V. , Olsson Marie‐Louise , Waddington Rachel , Wendel Mikael
Published: February 2006

Dentine sialoprotein (DSP) represents 5–8% of all non‐collagenous proteins present in the tooth, but, together with dentine phosphoprotein, has been shown to be vital for correct tooth formation. Recently, the existence of a highly glycosylated form of porcine DSP has been reported and it was shown to possess glycosaminoglycan (GAG) chains. The current investigation confirms that this is also the case for bovine DSP and has further characterized these carbohydrates. Dentine sialoprotein was purified from bovine dentine extracts by anion exchange chromatography and identified by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE), western blotting, and mass spectroscopy. An increase in molecular mass was observed, from 120 kDa to greater than 250 kDa, with a corresponding rise in anionic strength. Cellulose acetate electrophoresis and western blotting indicated the presence of chondroitin sulfate GAG chains within these dentine fractions. Further examination using sequential digestion with chondroitinase AC and N‐glycosidase cleaved the samples first to 95 kDa and then to 80 kDa, respectively, confirming a high level of glycosylation. These results support the classification of bovine DSP as a proteoglycan, and that the carbohydrate substitutions may contribute to the functional properties of DSP.
Preferences over dental restorative materials among young patients and dental professionals
Authors: Espelid Ivar , Cairns John , Askildsen Jan E. , Qvist Vibeke , Gaarden Torunn , Tveit Anne B.
Published: February 2006

Knowledge of the patient's view is necessary, as patients' rights are an issue of increasing importance in dental practice. This study aimed to examine how dentists (n = 42), dental assistants (n = 65), and young dental patients (n = 306) in Norway and Denmark valued three attributes of dental restorations, namely, expected longevity, the appearance, and the risk of an adverse reaction. According to the discrete choice method, participants were presented with several scenarios, describing different levels of the attributes, for comparison of two restorations (A and B). The differences among patients, dentists, and dental assistants were examined by logistic regression analyses. The likelihood of a dentist favoring one restoration over another was very sensitive to the difference in the expected longevity of the restorations, and much less to differences in visibility. The patients had considerable sensitivity to differences in visibility and much less to differences in duration. Danish teenagers attach less importance to visibility of the restoration and greater importance to the risk of an adverse reaction than Norwegian teenagers. All differences were statistically significant. Preferences associated with properties of dental restorations differ between teenage patients and dental professionals and this should be addressed in clinical decision‐making.
Effect of interleukin‐10 on gene expression of osteoclastogenic regulatory molecules in the rat dental follicle
Authors: Liu Dawen , Yao Shaomian , Wise Gary E.
Published: February 2006

The aim of this study was to determine the effect of interleukin‐10 (IL‐10) on the gene expression of osteoclastogenic regulatory molecules in rat dental follicle cells. Interleukin‐10 is an anti‐inflammatory cytokine that inhibits alveolar bone resorption, but the molecular basis for this is unknown. Alveolar bone resorption is required for tooth eruption and the dental follicle functions to regulate the osteoclastogenesis needed for eruption. It does this by regulating its expression of receptor activator of nuclear factor‐kappa B ligand (RANKL), colony‐stimulating factor‐1 (CSF‐1), and osteoprotegerin (OPG). In this study, dental follicle cells were treated with IL‐10, and the effect on gene expression of CSF‐1, RANKL, and OPG was measured by reverse transcription–polymerase chain reaction (RT–PCR). Interleukin‐10 enhanced the expression of OPG and down‐regulated the expression of RANKL and CSF‐1. Laser capture microdissection was carried out to detect IL‐10 gene expression in the dental follicle. Knockdown of the IL‐10 gene expression in the follicle cells was accomplished using a short interfering RNA (siRNA) targeting IL‐10 mRNA. In these knockdowns, RANKL expression was increased and OPG expression was decreased. All of these results suggest that IL‐10 inhibits bone resorption by up‐regulating OPG expression while down‐regulating expression of RANKL and CSF‐1.
Porcine dentin matrix protein 1: gene structure, cDNA sequence, and expression in teeth
Authors: Kim Jung‐Wook , Yamakoshi Yasuo , Iwata Takanori , Hu Yuan Yuan , Zhang Hengmin , Hu Jan C.‐C. , Simmer James P.
Published: February 2006

Dentin matrix protein 1 (DMP1) is an acidic non‐collagenous protein that is necessary for the proper biomineralization of bone, cartilage, cementum, dentin, and enamel. Dentin matrix protein 1 is highly phosphorylated and potentially glycosylated, but there is no experimental data identifying which specific amino acids are modified. For the purpose of facilitating the characterization of DMP1 from pig, which has the advantage of large developing teeth for obtaining protein in quantity and extensive structural information concerning other tooth matrix proteins, we characterized the porcine DMP1 cDNA and gene structure, raised anti‐peptide immunoglobulins that are specific for porcine DMP1, and detected DMP1 protein in porcine tooth extracts and histological sections. Porcine DMP1 has 510 amino acids, including a 16‐amino acid signal peptide. The deduced molecular weight of the secreted, unmodified protein is 53.5 kDa. The protein has 93 serines and 12 threonines in the appropriate context for phosphorylation, and four asparagines in a context suitable for glycosylation. Dentin matrix protein 1 protein bands with apparent molecular weights between 30 and 45 kDa were observed in partially purified dentin extracts. In developing teeth, immunohistochemistry localized DMP1 in odontoblasts and the dentinal tubules of mineralized dentin and in ameloblasts, but not in the enamel matrix.
Restriction Fragment Length Polymorphism Analysis of Large Subunit rDNA of Symbiotic Dinoflagellates from Scleractinian Corals in the Zhubi Coral Reef of the Nansha Islands
Authors: Huang Hui , Dong Zhi‐Jun , Huang Liang‐Min , Zhang Jun‐Bin
Published: February 2006

Zooxanthellae are very important for the coral reef ecosystem. The diversity of coral hosts is high in the South China Sea, but the diversity of zooxanthellae has not yet been investigated. We chose the Zhubi Coral Reef of the Nansha Islands as the region to be surveyed in the present study because it represents a typical tropical coral reef of the South China Sea and we investigated zooxanthellae diversity in 10 host scleractinian coral species using polymerase chain reaction (PCR) of the large subunit rRNA and restriction fragment length polymorphism (RFLP) patterns. Pocillopora verrucosa, Acropora pelifera, Acropora millepora, Fungia fungites, Galaxea fascicularis, and Acropora pruinosa harbor Clade C, Goniastrea aspera harbors Clade D, and Acropora formosa harbors Clades D and C. Therefore, the Clade C is the dominant type in the Zhubi Coral Reef of the Nansha Islands. Furthermore, the results of the present also disprove what has been widely accepted, namely that one coral host harbors only one algal symbiont. The coral‐algal symbiosis is flexible, which may be an important mechanism for surviving coral bleaching. Meanwhile, on the basis of the results of the present study, we think that Symbiodinium Clade D may be more tolerant to stress than Symbiodinium Clade C.

(Managing editor: Ya‐Qin Han)
Distribution of Vascular Plant Species Richness Along an Elevational Gradient in the Dongling Mountains, Beijing, China
Authors: Ren Hai‐Bao , Niu Shu‐Kui , Zhang Lin‐Yan , Ma Ke‐Ping
Published: February 2006

Quantifying spatial patterns of species richness and determining the processes that give rise to these patterns are core problems in biodiversity theory. The aim of the present paper was to more accurately detect patterns of vascular species richness at different scales along altitudinal gradients in order to further our understanding of biodiversity patterns and to facilitate studies on relationships between biodiversity and environmental factors. Species richness patterns of total vascular plants species, including trees, shrubs, and herbs, were measured along an altitudinal gradient on one transect on a shady slope in the Dongling Mountains, near Beijing, China. Direct gradient analysis, regression analysis, and geostatistics were applied to describe the spatial patterns of species richness. We found that total vascular species richness did not exhibit a linear pattern of change with altitude, although species groups with different ecological features showed strong elevational patterns different from total species richness. In addition to total vascular plants, analysis of trees, shrubs, and herbs demonstrated remarkable hierarchical structures of species richness with altitude (i.e. patchy structures at small scales and gradients at large scales). Species richness for trees and shrubs had similar spatial characteristics at different scales, but differed from herbs. These results indicated that species groups with similar ecological features exhibit similar biodiversity patterns with altitude, and studies of biodiversity based on species groups with similar ecological properties or life forms would advance our understanding of variations in species diversity. Furthermore, the gradients or trends appeared to be due mainly to local variations in species richness means with altitude. We also found that the range of spatial scale dependencies of species richness for total vascular plants, trees, shrubs, and herbs was relatively large. Thus, to detect the relationships between species richness with environmental factors along altitudinal gradients, it was necessary to quantify the scale dependencies of environmental factors in the sampling design or when establishing non‐linear models.

(Managing editor: Ya‐Qin Han)
The Putative Ser/Thr Protein Kinase GeneGmAAPKfrom Soybean is Regulated by Abiotic Stress
Authors: Luo Guang‐Zuo , Wang Yong‐Jun , Xie Zong‐Ming , Gai Jun‐Yi , Zhang Jin‐Song , Chen Shou‐Yi
Published: February 2006

Osmotic stress caused by dehydration or high‐salt conditions poses a major environmental challenge for plant growth and development. Many studies have shown that protein kinases are important regulators during osmotic stress in plants. In the present study, we describeGmAAPK, a soybean(Glycine max(L.) Merr.) gene coding for a putative serine/threonine protein kinase (abscisic acid (ABA)‐activated protein kinase (AAPK)). The cDNA forGmAAPKis 1 409 bp long and contains a single long open reading frame representing a complete coding region of 359 amino acids.GmAAPKwas mapped onto the D1 a+Q linkage group. Its transcripts are expressed in all tissues, but at high levels in the cotyledon.GmAAPKmRNA was induced by polyethylene glycol, ABA, Ca2+, and Na+, but not cold (4 °C) treatments in soybean leaves. The results suggest that GmAAPK may participate in the regulatory process during osmotic stresses in soybean.

(Managing editor: Li‐Hui Zhao)
Culturing the Segments of Bryopsis hypnoides Lamouroux Thalli Regenerated from Protoplast Aggregations
Authors: Wang Guang‐Ce , Tseng Cheng‐Kui
Published: February 2006

Bryopsis hypnoides Lamouroux was regenerated in vitro from the protoplasm squeezed out from wild algae and the regenerated individuals had an advantage over individuals from the wild in terms of growth. Culturing of segments of thalli also showed that segments from the regenerated algae grew better than those from individuals from the wild. The segment that corresponds to a part of a cell, at least a part of the protoplasm, can develop into a mature individual, including rhizoid and thallus, suggesting that a multinucleate alga, such as B. hypnoides, is different from higher plants, whose totipotency is based on an intact cell (or protoplasm). Further cultivation of mature individuals from segments indicated that the organelles in the thallus had two ways in which they could survive when the alga was on the decline: (i) the organelles were transferred into a ball with a gelatinous envelope through a formed pipe and the ball seemed to be capable of being propagated; and (ii) the organelles were aggregated in the thallus and then moved to the outside. An interesting result is that one organelle aggregation located outside the thallus germinated and developed into a mature alga, although most organelle aggregations gradually lost vitality and died. The results of the present study reveal that the aggregation of organelles can regenerate a stronger organism than individuals from the wild owing to the complete exchange of genetic material and may possibly enable organelles to survive in unfavorable surroundings.

(Managing editor: Wei Wang)
Cloning and Expressional Studies of the Voltage‐dependent Anion Channel Gene from Brassica rapa L.
Authors: Wang Jiang , Zhang Li‐Da , Zuo Kai‐Jing , Qian Hong‐Mei , Cao You‐Fang , Tang Ke‐Xuan
Published: February 2006

The voltage‐dependent anion channel (VDAC) plays an essential role in the permeability of mitochondrial membrane. In the present study, we isolated a novel VDAC gene (brvdac) based on the assembly of expressed sequence tag sequences from Brassica rapa L. and explored its differential expression patterns in growth, tissues, abiotic stress, and stress recovery. Results of a tissue‐specific expression study in young seedlings indicated that, of all tissues tested, brvdac expression was the highest in the leaves. Under cold, drought, and salt stresses, brvdac expression showed a transient increase, and then returned to normal levels when the stress was removed. When plants were exposed to heat shock, there was no increase in brvdac expression, whereas during recovery a quick and considerable increase in expression was observed. These observations indicate that dissimilar modulations of brvdac transcription may occur when plant cells encounter heat shock and the other three types of stress. In addition, phylogenetic analysis implied that an earlier duplication of vdac probably occurred before the divergence between monocotyledons and dicotyledons.

(Managing editor: Li‐Hui Zhao)
Cloning and Expression of Low Molecular Weight Glutenin Genes from the Chinese Elite Wheat Cultivar “Xiaoyan 54”
Authors: Wang Xin‐Yu , Liu Kun‐Fan , Guo Wang‐Zhen
Published: February 2006

The low molecular weight (LMW) glutenin subunits account for 40% of wheat gluten protein content by mass and these proteins are considered to significantly affect dough quality characteristics. Five new full‐length LMW glutenin genes (designated LMW‐5, LMW‐7, LMW‐42, LMW‐58, and LMW‐34) were isolated from the Chinese elite wheat cultivar “Xiaoyan 54” by PCR amplification of genomic DNA using a pair of degenerate primers designed from the conserved sequences of the N‐ and C‐terminal regions of published LMW glutenin genes. Deduced amino acid sequence analysis showed that LMW‐5 belongs to the LMW‐i type genes and that the other four belong to LMW‐m type genes. Sequence comparisons revealed that point mutations occasionally occurred in signal peptide and N‐terminus domains and often existed in domain III and domain V. Small insertions and deletions are represented in the repetitive domain. There is a stop codon after amino acid position 110 in the repetitive domain of LMW‐34, indicating that it is a pseudogene. The other four genes have complete open reading frames and the putative mature regions of these genes were subcloned into pET‐30a expression vector and successfully expressed in Escherichia coli. Protein sodium dodecyl sulfate‐polyacrylamide gel electro‐phoresis analysis showed that all proteins expressed in E. coli by the four genes could be related to B‐group LMW glutenin subunits of wheat.

(Managing editor: Li‐Hui Zhao)
Calcium‐Mediated Mitochondrial Permeability Transition Involved in Hydrogen Peroxide‐Induced Apoptosis in Tobacco Protoplasts
Authors: Wang Yuan , Lin Jiu‐Sheng , Wang Gen‐Xuan
Published: February 2006

In the present study, we focused on whether intracellular free Ca2+ ([Ca2+]i) regulates the formation of mitochondrial permeability transition pore (MPTP) in H2O2‐induced apoptosis in tobacco protoplasts. It was shown that the decrease in mitochondrial membrane potential (ΔΨm) preceded the appearance of H2O2‐induced apoptosis; pretreatment with the specific MPTP inhibitor cyclosporine A, which also inhibits Ca2+ cycling by the mitochondria, effectively retarded apoptosis and the decrease in ΔΨm. Apoptosis and decreased ΔΨm were exacerbated by CaCl2, whereas the plasma membrane voltage‐dependent Ca2+ channel blocker lanthanum chloride (LaCl3) attentuated these responses. Chelation of extracellular Ca2+ with EGTA almost totally inhibited apoptosis and the decrease in ΔΨm induced by H2O2. The time‐course of changes in [Ca2+]i in apoptosis was detected using the Ca2+ probe Fluo‐3 AM. These studies showed that [Ca2+]i was increased at the very early stage of H2O2‐induced apoptosis. The EGTA evidently inhibited the increase in [Ca2+]i induced by H2O2, whereas it was only partially inhibited by LaCl3. The results suggest that H2O2 may elevate cytoplasmic free Ca2+ concentrations in tobacco protoplasts, which mainly results from the entry of extracellular Ca2+, to regulate mitochondrial permeability transition. The signaling pathway of [Ca2+]i‐mediated mitochondrial permeability transition was associated with H2O2‐induced apoptosis in tobacco protoplasts.

(Managing editor: Ping He).
Global Warming: Can Existing Reserves Really Preserve Current Levels of Biological Diversity?
Authors: Li Mai‐He , Kräuchi Norbert , Gao Su‐Ping
Published: February 2006

Paleoecological evidence and paleoclimatic records indicate that there was a plant poleward migration in latitude and an upward shift in elevation with increased temperatures after the last glaciation. Recent studies have shown that global warming over the past 100 years has been having a noticeable effect on living systems. Current global warming is causing a poleward and upward shift in the range of many plants and animals. Climate change, in connection with other global changes, is threatening the survival of a wide range of plant and animal species. This raises the question: can existing reserves really preserve current levels of biological diversity in the long term given the present rapid pace of climate change? The present paper deals with this question in the context of the responses of plants and animals to global climate change, based on a literature review. Consequently, we recommend expanding reserves towards the poles and/or towards higher altitudes, to permit species to shift their ranges to keep pace with global warming.

(Managing editor: Ya‐Qin Han)
Involvement of Hydrogen Peroxide Generated by Polyamine Oxidative Degradation in the Development of Lateral Roots in Soybean
Authors: Su Guo‐Xing , Zhang Wen‐Hua , Liu You‐Liang
Published: February 2006

In order to determine whether hydrogen peroxide (H2O2) generated by polyamine oxidative degradation is involved in the development of lateral roots in soybean, the length and the number of lateral roots, the activities of polyamine oxidases and diamine oxidases, and the endogenous free polyamine and H2O2 content were analyzed in soybean (Glycine max (Linn.) Merr.) main roots of 2‐d‐old seedlings after treatments for 2 d with exogenous β‐hydroxyethylhydrazine (an inhibitor of polyamine oxidases), H2O2, putrescine, cyclohexylamine (an inhibitor of spermidine synthase) or N, N′‐dimethylthiourea (a scavenger of hydrogen peroxide). β‐hydroxyethylhydrazine treatment strongly inhibited the development of lateral roots in soybean seedlings, reduced the activities of polyamine oxidases and diamine oxidases, decreased H2O2 levels, and led to the accumulation of endogenous polyamines in the main roots. The inhibitory effect of β‐hydroxyethylhydrazine on root development could be alleviated by exogenously applied 10 μmol/L H2O2 (a major product of polyamine oxidation). Treatment with cyclohexylamine and putrescine promoted root growth slightly, but treatment with cyclohexylamine plus N, N′‐dimethylthiourea or putrescine plus N, N′‐dimethylthiourea prevented the development of soybean lateral roots. The effects of these treatments on the development of soybean lateral roots were consistent with the changes in endogenous H2O2 levels. These results suggest that the development of soybean lateral roots is associated with the oxidative degradation of polyamines, and that their products, especially H2O2, are likely to play an important role in the growth of soybean lateral roots.

(Managing editor: Ping He)
Analysis of Steady Ground Water Flow Toward Wells in a Confined‐Unconfined Aquifer
Authors: Chong‐Xi Chen , Li‐Tang Hu , Xu‐Sheng Wang
Published: February 2006

A confined aquifer may become unconfined near the pumping wells when the water level falls below the confining unit in the case where the pumping rate is great and the excess hydraulic head over the top of the aquifer is small. Girinskii’s potential function is applied to analyze the steady ground water flow induced by pumping wells with a constant‐head boundary in a mixed confined‐unconfined aquifer. The solution of the single‐well problem is derived, and the critical radial distance at which the flow changes from confined to unconfined condition is obtained. Using image wells and the superposition method, an analytic solution is presented to study steady ground water flow induced by a group of pumping wells in an aquifer bounded by a river with constant head. A dimensionless function is introduced to determine whether a water table condition exists or not near the pumping wells. An example with three pumping wells is used to demonstrate the patterns of potentiometric surface and development of water table around the wells.
Mentoring—A complex relationship
Authors: Barker E. R.
Published: February 2006

Purpose: To address the process of mentoring the advanced practice nurse (APN) and provide suggestions for the formulation, implementation, and termination of the relationship.

Data sources: Research studies from nursing as well as other disciplines and personal experience as a mentor and protégé.

Conclusions: Mentoring is a dynamic and complex relationship that can support growth, increase synergy, and develop ways to succeed as an APN. Before entering into the relationship, care should be taken to assure compatibility between the mentor and the protégé. Major pitfalls include poor communication patterns and inadequate identification of objectives. Keys for repair or termination of the relationship include personal introspection, honest and nonblaming communication, and development of alternative support networks.

Implications for practice: Successful mentoring relationships improve professional growth, competency, and productivity. They also form the basis for ongoing preparation of a new generation of APNs.
Fractured penis
Authors: Cole Frank L. , Vogler Robert W.
Published: February 2006

Purpose: To provide nurse practitioners (NP) with information concerning the uncommon occurrence of penile fracture, a review of the anatomy and physiology of the penile shaft, signs and symptoms to be included in assessment, diagnostic tests, treatment, and referral are discussed.

Data sources: Current literature available in journals and textbook, and clinical experience.

Conclusions: Penile fracture, although an uncommon incident, is an urgent condition that requires a urology consult and surgical repair.

Implications for practice: Because of the serious nature of this injury and the potential for complications, NPs need to obtain an urgent urology consult when penile fracture is suspected or diagnosed. The characteristic typical clinical presentation usually eliminates the need for expensive or invasive tests for diagnosis.
Thermophilic aerobic wastewater treatment of waste metalworking fluids
Authors: Cheng Christina , Phipps David , Alkhaddar Rafid M.
Published: February 2006

An investigation into aerobic biological wastewater treatment was conducted over the temperature range 25–75°C in a semi‐batch bioreactor using waste metalworking fluids (MWFs) generated from Liverpool John Moores University's engineering workshop. The best treatment performance in terms of chemical oxygen demand (COD) removal occurred at 50°C (97.27%), with an operational time of 77.5 h. Cell viability was observed throughout the operation and it was found that higher temperature did not directly correlate to low viability. Effluent turbidity reduced considerably from 35 to 50°C and increased thereafter. Even when the system encountered alkaline shock, the overall performance was not affected, thus indicating how stable the system was. The results of this study indicate that an existing industrial‐activated sludge plant could be used to treat waste MWFs under thermophilic conditions. The COD reduction was significant but further investigation into biodegradation of recalcitrant compounds is needed to achieve optimum performance.