bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lead levels in primary teeth of children living in Mexico City
Authors: Hernández‐Guerrero J. C. , Jiménez‐Farfán M. D. , Belmont R. , Ledesma‐Montes C. , Baez A. 
Published: May 2004

Summary.  Objective.  The aim of this study was to discover the lead concentration in primary teeth extracted in the peripheral clinics of the Faculty of Dentistry, UNAM (Mexico City).Design.  One hundred healthy primary teeth were collected from 2 to 13‐year‐old children (52 girls and 48 boys). Sixty‐six were maxillary teeth and 34 were mandibular teeth. Lead concentrations were measured by Graphite Furnace Atomic Absorption Spectrophotometry.Results.  Our results indicate that lead concentration in the 10–13‐year‐old group (7·7 µg/g−1) was higher than in the other groups. Geometric mean lead concentration was higher in girls than in boys (7·3 µg/g−1 and 6·3 µg/g−1, respectively). Maxillary teeth had higher lead concentrations than mandibular teeth and primary canines showed the highest mean lead concentration followed by incisors and molars. Teeth from children living in the south‐east area (which according to the Mexico City's Pollution Center data is the more polluted area), presented the highest lead concentration but no statistically significant difference was found among teeth from the different areas.Conclusions.  Our results suggest that age, gender and place of residence are not related to the lead concentration in human primary teeth. This fact seems to indicate the ubiquitous presence of lead in the whole atmosphere of Mexico City and suggests that zones of residence do not appear to influence tooth lead concentration.
Dental anxiety in a students’ paediatric dental clinic: children, parents and students
Authors: Peretz Benjamin , Nazarian Yaron , Bimstein Enrique 
Published: May 2004

Summary.  Objective.  The purpose of the present study was to investigate the dental anxieties of children, parents and student caregivers in a dental school environment.Methods.  Eighty‐eight children, parents and the dental students who treated the children were included in the study. They were asked to complete questionnaires which gathered information about demographics and dental anxiety using the Dental Anxiety Scale (DAS). Students were also asked to respond to a visual analogue scale (VAS) to assess their anxiety prior to treating children.Results.  Significant differences were observed between the mean DAS of the children compared to the students (8·8 ± 3·9 and 7·3 ± 2·7, respectively), and between the scores of the parents and the students (8·3 ± 2·9 and 7·3 ± 2·7, respectively). No significance was noted between the mean DAS scores of the children and those of the parents. The number of children in family did not influence the mean DAS of the children. Parents’ age, education or place of birth did not influence the mean DAS of the parents or the children. The mean DAS of children who reacted excellently in previous treatments scored significantly lower in DAS compared with children who were fearful. Female dental students demonstrated higher DAS and VAS scores than male students. Students’ seniority, type of last treatment that they received, time since last treatment, parenthood or self‐ranking in class did not seem to significantly influence their DAS or VAS scores. A strong correlation in DAS scores between parents and children was found (r = 0·41, P = 0·0001). No correlation between children's and students’ DAS scores was found.Conclusions.  Students’ dental anxiety, or their anxiety prior to treating a child, may not be directly associated with the child's dental anxiety. However, a positive correlation exists between parental and children's dental anxiety.
Aetiology, diagnosis and treatment of posterior cross‐bites in the primary dentition
Authors: Malandris M. , Mahoney E. K. 
Published: May 2004

Summary.  Introduction.  Children who present with a posterior cross‐bite in the primary dentition may be predisposed to long‐term detrimental consequences if the condition is left untreated. Controversy exists in the literature as to the most appropriate time to treat this condition.Objectives.  The aim of this review is to evaluate the need for correcting posterior cross‐bites in the primary dentition based on the current understanding of the aetiology, likelihood of self‐correction, and consequences of various forms of this malocclusion persisting into the mixed and permanent dentitions. A review of the reported treatment options for management of this condition is also presented.Methods.  Literature pertaining to the epidemiology and management of posterior cross‐bites in the primary dentition are reviewed.Conclusion.  Posterior cross‐bites in the primary dentition are relatively common and their causes are numerous. Because a significant proportion of posterior cross‐bites self‐correct beyond the primary dentition, routine correction in the primary dentition phase cannot be advocated. A unilateral posterior cross‐bite as a result of a functional displacement of the mandible is one of the few malocclusions which should be considered for correction in the primary dentition. Further research is needed in the management of this condition.
Effect of diode laser and fluoride varnish on initial surface demineralization of primary dentition enamel: an in vitro study
Authors: Santaella M. R. L. A. , Braun A. , Matson E. , Frentzen M. 
Published: May 2004

Summary.  Introduction.  Previous investigations have demonstrated improved enamel caries resistance after laser irradiation. The purpose of this in vitro study was to assess the caries‐preventive potential of 809 nm diode laser treatment of the enamel of primary teeth compared to topical fluoride application.Methods.  Eighty samples of sound primary teeth were embedded in plastic and stored in saline solution. The enamel surface of 80 samples was polished in an area of 2 × 2 mm. These tooth specimens were randomly assigned to one control and three test groups: (1) no treatment/control; (2) application of 0·1 mg of fluoride varnish (Duraphat®) for 6 h; (3) diode laser application (809 nm, 140 mJ, 50 Hz, Ø 600 µm fibre, contact mode, absorber, 1 min; ORA‐LASER01® I.S.T.); and (4) combined application – laser/fluoride varnish. Caries‐like lesions were created by pH‐cycling. After lesion formation, longitudinal sections were taken and examined by polarized light microscopy.Results.  In the control group, all samples showed lesions up to 30 µm in depth. After laser application, lesions could be identified in 15 out of 20 samples. Topical fluoride treatment in groups 2 (varnish) and 4 (laser/varnish) completely inhibited the development of caries‐like lesions in all samples.Conclusion.  In this in vitro investigation, topical fluoride treatment enhances the resistance of sound enamel of primary teeth more effectively than diode laser application.
Anoda cristata control with glyphosate in narrow‐ and wide‐row soyabean
Authors: Puricelli E , Faccini D , Orioli G , Sabbatini M R 
Published: May 2004

SummaryExperiments evaluated the effect of glyphosate rate and Anoda cristata density, on crop and weed biomass and weed seed production in wide (70 cm) and narrow rows (35 cm) glyphosate‐resistant soyabean (Glycine max). Soyabean density was higher at 35 cm row spacing as an increase in planting rate in narrow‐row soyabean is recommended for producers in Argentina. Soyabean biomass at growth stage V4 (four nodes on the main stem with fully developed leaves beginning with the unifoliate leaves) was higher when grown on narrow than in wide‐rows but was not affected by the presence of A. cristata. At growth stage R5 (seed initiation – seed 3 mm long in a pod at one of the four uppermost nodes on the main stem, with a fully developed leaf and full canopy development), crop biomass was greater in narrow rows compared with wide rows with 12 plants m−2 of A. cristata. In narrow‐row soyabean, a single application of a reduced rate of glyphosate maintained soyabean biomass at R5 and provided excellent weed control regardless of weed density. In wide‐row soyabean control was reduced at the high weed density. Regardless of row spacing, A. cristata biomass and seed production were severely reduced by half of the recommended dose rate of glyphosate but the relationship between biomass and seed production was not altered. Glyphosate rates as low as 67.5 g a.e. ha−1 in narrow rows or 540 g a.e. ha−1 in wide rows provided excellent control of A. cristata. To minimize glyphosate use, planting narrow‐row soyabean are effective where A. cristata density is low.
Integrated management of Striga hermonthica in sorghum using a mycoherbicide and host plant resistance in the Nigerian Sudano‐Sahelian savanna
Authors: Marley P S , Aba D A , Shebayan J A Y , Musa R , Sanni A 
Published: May 2004

Summary Striga hermonthica is a major biotic constraint to sorghum production in Nigeria, sometimes causing total yield loss. Recommendations for Striga management often include the use of cultural and agronomic practices, herbicides and host plant resistance when available. The use of biological control has not been commercialized. Fusarium oxysporum (isolate PSM 197)‐based mycoherbicide was used in combination with selected sorghums (the Striga‐resistant cultivar Samsorg 40, and the Striga tolerant landrace Yar'ruruka) as an Integrated Striga Management strategy (ISM) in on‐farm trials in the Sudano‐Sahelian savanna of Nigeria. Crop stands were significantly (P = 0.05) higher in ISM compared with non‐ISM plots on which the mycoherbicide was not applied. Similarly, ISM plots had significantly (P = 0.05) lower Striga counts than non‐ISM plots. Striga emergence was reduced by ISM by around 95%. Sorghum yields were 49.6% higher where integrated management was used. Cost benefit analysis of the ISM package shows that use of the mycoherbicide increased the profitability of sorghum production on Striga‐infested soils. Farmers’ preferences monitored during and after the trials highlighted the need for careful selection and integration of control components into an ISM package.
Size and composition of the weed seedbank after 7 years of different cover‐crop‐maize management systems
Authors: Moonen A C , Bàrberi P 
Published: May 2004

SummaryThe objective of this study was to obtain detailed information on the long‐term weed suppression potential of four winter soil cover types included in an arable crop system managed at various input levels. We used weed seedbank size and composition to assess weed suppression potential. A field experiment was established in 1993 as a split‐split‐plot design with four replications, including two tillage systems [a conventional system (CS) including ploughing in the cover crops and a low‐input system (LIS) including no tillage with surface mulching of the cover crops] in the main plots, three mineral nitrogen fertilization rates for the main crop in the sub‐plots and four soil cover types (main crop residue, rye, crimson clover and subterranean clover) in the sub‐sub‐plots. Seedbank sampling took place in winter 2000/01. The weed seedbank was analysed with the seedling emergence method. Data were analysed using anova and multivariate techniques. Results indicated that the seedbank density in the LIS was about five times higher than in the conventional input system. In the CS, use of a rye cover crop resulted in a lower seedbank density with respect to the crop residue treatment (−25%), whereas in the LIS the subterranean clover cover crop decreased weed seedbank density as compared with the other cover crops and the crop residue treatment (−22% on average). Differences in species composition were mainly related to tillage system. Implications for cover crop management and the development of sustainable cropping systems are discussed.
Spatial stability of Avena sterilis ssp. ludoviciana populations under annual applications of low rates of imazamethabenz
Authors: Barroso J , Fernàndez‐Quintanilla C , Ruiz D , Hernaiz P , Rew LJ 
Published: May 2004

SummaryLong‐term experiments were conducted in two winter barley fields in central Spain to determine the spatial stability of Avena sterilis ssp. ludoviciana populations under annual applications of low rates of imazamethabenz herbicide. Weed density was sampled every year (over 5 years in the first field and over 3 years in the second) on the same grid locations prior to herbicide application. Although weed patches were stable in their location, weed density decreased in most of the years. In the first field, the populations decreased exponentially over the 5‐year period. The rates of population decline were dependent on the initial density of the population, being higher for the central core of the patches and lower for the low‐density areas. Under the conditions present in this experiment, it was possible to reduce heavy weed patches (up to 1200 seedlings m−2) down to relatively safe levels (18 seedlings m−2) in a period of 3 years using a density‐specific control programme, applying low rates of herbicides when weed densities were below a given level (1000 seedlings m−2). However, under adverse environmental conditions, half rates of the herbicide failed to control the weed populations adequately. The stability of the location of patches of A. sterilis ssp. ludoviciana suggest that weed seedling distributions mapped in one year are good predictors of future seedling distributions. However, the actual densities established each year will depend on the control level achieved the previous year and the climatic conditions present during the establishment period.
Resistance of Camelina microcarpa to acetolactate synthase inhibiting herbicides
Authors: Hanson B D , Park K W , Mallory‐Smith C A , Thill D C 
Published: May 2004

SummaryAn accession of Camelina microcarpa suspected to be resistant to sulfonylurea herbicides was identified in Oregon in 1998 field experiments. Greenhouse research confirmed that the putative resistant biotype was resistant to chlorsulfuron and metsulfuron on a whole plant level. Compared with the resistant (R) biotype, the susceptible (S) biotype was 1000 and 10 000‐fold more sensitive to metsulfuron and chlorsulfuron respectively. The R biotype was also resistant to other sulfonylurea, sulfonylaminocarbonyl‐triazolinone, imidazolinone and triazolopyrimidine herbicides. An in vivo enzyme assay indicated that acetolactate synthase (ALS) from the R plants required 111 times more chlorsulfuron to inhibit activity by 50% compared with the amount required to have a similar effect on ALS from S plants. Analysis of the nucleotide and amino acid sequences demonstrated that a single‐point mutation from G to T in the als1 gene conferred the change from the amino acid tryptophan to leucine at position 572 in the resistant biotype. This research confirmed that ALS inhibitor resistance in an Oregon accession of C. microcarpa is based on an altered target site conferred by a single‐point mutation.
Synergistic interactions between an exotic honeybee and an exotic weed: pollination of Lantana camara in Australia
Authors: Goulson D , Derwent L C 
Published: May 2004

Summary Lantana camara, a woody shrub originating in south and central America, is among the most widespread and troublesome exotic weeds of the old‐world tropics. It invades pasture, crops and native ecosystems, causing substantial economic losses and environmental degradation. In Australia alone, L. camara is currently estimated to cover c. 40 000 km2 . In glasshouse studies we demonstrate that L. camara requires cross‐pollination to set fruit, and that honeybee visits result in effective pollination. Field studies carried out in Queensland, Australia, suggest that fruit set is limited by pollinator abundance, and that the main pollinator of L. camara throughout a substantial portion of its Australian range appears to be the honeybee, Apis mellifera. Seed set was strongly correlated with honeybee abundance, and at many sites, particularly in southern Queensland, honeybees were the only recorded flower visitors. Of 63 sites that were visited, seed set was highest at five sites where only honeybees were present. Hives are frequently stationed within and adjacent to areas such as National Parks that are threatened by this noxious weed. Management of honeybee populations may provide a powerful tool for cost‐effective control of L. camara that has previously been overlooked. We suggest that there are probably many other weeds, both in Australia and elsewhere, that benefit from honeybee pollination.
Characterization of the Orobanche–Medicago truncatula association for studying early stages of the parasite–host interaction
Authors: Rodríguez‐Conde M F , Moreno M T , Cubero J I , Rubiales D 
Published: May 2004

SummaryThere is an increasing interest in the legume species Medicago truncatula as a model plant for structural and functional genomic studies that can be used to identify agronomically important genes in legumes. Field screening has shown very high levels of resistance to Orobanche crenata in M. truncatula. However, in vitro studies with O. crenata, Orobanche foetida, Orobanche ramosa and Orobanche minor showed useful variation among accessions at early stages of the parasite–host interaction. Significant differences were observed in the levels of germination of O. crenata and O. foetida seeds induced by different accessions of M. truncatula. Only limited germination was observed on accession SA‐4327. All accessions induced little O. ramosa and O. minor germination. Accessions also varied in the number of O. crenata and O. foetida attachments supported, with few developing on accession SA‐27774. The variation observed for induction of germination and of subsequent attachment will be useful to isolating and characterizing genes involved in the early stages of Orobanche–host plant interaction and for the study of the biosynthetic pathways of production for germination stimulants.
Visualization of the effect of a surfactant on the uptake of xenobiotics into plant foliage by confocal laser scanning microscopy
Authors: Liu Z Q , Gaskin R E , Zabkiwicz J A 
Published: May 2004

SummaryA radiolabelling method is generally used to determine the foliar uptake of xenobiotics. This technique cannot provide any information on the localization of chemicals inside leaf tissues. The influence of an alcohol ethoxylate surfactant on the uptake of three fluorescent dyes, difluorofluorescein (hydrophilic), rhodamine B (moderately lipophilic) and a naphthalimide dye (lipophilic), into the leaves of three contrasting species, bean (Vicia faba), wheat (Triticum aestivum) and cabbage (Brassica oleracea), at 16 h after treatment was measured using a conventional wash‐off method and also visualized in vivo by confocal laser scanning microscopy (CLSM). Whereas the lipophilic dyes showed greater intrinsic uptake than the hydrophilic one, the enhancing effect of the surfactant on uptake was more pronounced for the latter. CLSM revealed that the presence of the surfactant increased the transport of difluorofluorescein into the epidermal cells of bean and wheat leaves, but not cabbage leaves. Rhodamine B showed greatest transcuticular diffusion in all three species, but most of the dye moved into the vacuole of the epidermal cells. The naphthalimide dye was strongly retained by the wax–cuticle layer of all species, even in the presence of the surfactant. CLSM has proven to be an attractive tool for studying xenobiotic diffusion. The results obtained using fluorescent dyes are believed to be applicable to the foliar uptake of herbicides.
Impact of HCV infection on first cadaveric renal transplantation, a single center experience
Authors: Lin Hsin‐Hung , Huang Chiu‐Ching , Huang Jeng‐Yi , Yang Chih‐Wei , Wu Mai‐Szu , Fang Ji‐Tseng , Yu Chun‐Chen , Chiang Yang‐Jen , Chu Sheng‐Hsieh 
Published: May 2004

Abstract: Background: Controversy still persists regarding the impact of HCV infection on renal transplant recipients. This study aimed to evaluate the effect of anti‐HCV antibody status on patients and grafts of renal transplants at a single center.Methods: We examined 299 first cadaveric renal transplants performed between July 1981 and May 2000 at our hospital, including 129 patients with anti‐HCV antibody positive (HCV+ group) and 170 patients with anti‐HCV antibody negative (HCV− group). The HBsAg of the 299 patients were all negative throughout the follow‐up period. Causes of graft failure and patient death were analyzed. Patient and graft cumulative survival were compared between HCV+ and HCV− groups. Multivariate analysis with Cox proportional hazard model were calculated for risk hazards of outcome.Results: Overall cumulative patient survival was 97.72, 85.63 and 71.31% at 1, 10, and 15 yr, respectively, in the HCV+ group, compared with 95.02, 67.85 and 59.83% at 1, 10 and 15 yr, respectively, in the HCV− group (p = 0.014). The major cause of patient death in both groups was infection with 26.67% in HCV+ group and 60.87% in HCV− group. Cumulative graft survival in the HCV+ group revealed 92.26, 55.97 and 26.16% at 1, 10 and 15 yr, respectively, compared with 88.07, 58.34 and 58.32% at 1, 10 and 15 yr, respectively, in the HCV− group (p = 0.700). The major cause of graft failure was chronic allograft dysfunction (56.82%) in HCV+ group, and patient death (32.43%) in the HCV− group. Multivariate analysis of patient survival revealed anti‐HCV antibody+ had lesser risk hazard (aRR: 0.30, p = 0.002), chronic hepatitis had higher risk hazard (aRR: 1.90, p = 0.135), male recipient had higher risk hazard (aRR: 2.18, p = 0.051), and older recipients (age >55) also had higher risk hazard (aRR: 4.21, p = 0.063). Analysis of graft survival revealed only older donors (age >35) had higher risk hazard (aRR: 1.90, p = 0.081).Conclusions: The study revealed that patients with anti‐HCV antibody had higher incidence of chronic hepatitis, chronic allograft dysfunction and post‐transplantation nephrotic syndrome. Graft survival tended lower in the very long time. However, patients with anti‐HCV antibodies had better patient survival when compared with patients without HCV antibodies up to 15 yr follow up. Patients of hepatitis C group without clinical chronic hepatitis was associated with best patient survival.
Severe hemolytic anemia due to passenger lymphocytes after living‐related bowel transplant
Authors: Panaro F , DeChristopher PJ , Rondelli D , Testa G , Sankary H , Popescu M , Benedetti E 
Published: May 2004

Abstract: Background: Hemolytic anemia following solid organ transplant may be caused by ‘passenger’ lymphocytes producing antibodies against erythrocytes. This phenomenon has never been described after intestinal transplant.Materials and methods: We report a case of severe, immune‐mediated hemolysis due to symptomatic passenger lymphocyte syndrome (PLS) in a 4‐yr‐old recipient of living donor small bowel transplant. The Coombs’‐positive hemolysis was caused by anti‐A,B antibodies derived from donor lymphocytes in an ABO‐compatible donor–recipient pair (O into A).Results: This complication was successfully and efficiently treated by the novel combined use of group O RBC transfusion, plasmapheresis and rituximab (anti‐CD20).Conclusions: A severe hemolytic anemia due to PLS can occur in bowel transplantation. This complication should be considered when performing ABO‐incompatible bowel transplant with a blood group O donor and an A or B recipient. Treatment with plasmapheresis, blood group O transfusion and rituximab has proved successful in our case.