bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synergy and specificity of two Na+–aromatic amino acid symporters in the model alimentary canal of mosquito larvae
Authors: Okech Bernard A. , Meleshkevitch Ella A. , Miller Melissa M. , Popova Lyudmila B. , Harvey William R. , Boudko Dmitri Y. 
Published: May 2008

SUMMARYThe nutrient amino acid transporter (NAT) subfamily is the largest subdivision of the sodium neurotransmitter symporter family (SNF; also known as SLC6; HUGO). There are seven members of the NAT population in the African malaria mosquito Anopheles gambiae, two of which, AgNAT6 and AgNAT8,preferably transport indole- and phenyl-branched substrates, respectively. The relative expression and distribution of these aromatic NATs were examined with transporter-specific antibodies in Xenopus oocytes and mosquito larval alimentary canal, representing heterologous and tissue expression systems, respectively. NAT-specific aromatic-substrate-induced currents strongly corresponded with specific accumulation of both transporters in the plasma membrane of oocytes. Immunolabeling revealed elevated expressions of both transporters in specific regions of the larval alimentary canal,including salivary glands, cardia, gastric caeca, posterior midgut and Malpighian tubules. Differences in relative expression densities and spatial distribution of the transporters were prominent in virtually all of these regions, suggesting unique profiles of the aromatic amino acid absorption. For the first time reversal of the location of a transporter between apical and basal membranes was identified in posterior and anterior epithelial domains corresponding with secretory and absorptive epithelial functions,respectively. Both aromatic NATs formed putative homodimers in the larval gut whereas functional monomers were over-expressed heterologously in Xenopus oocytes. The results unequivocally suggest functional synergy between substrate-specific AgNAT6 and AgNAT8 in intracellular absorption of aromatic amino acids. More broadly, they suggest that the specific selectivity, regional expression and polarized membrane docking of NATs represent key adaptive traits shaping functional patterns of essential amino acid absorption in the metazoan alimentary canal and other tissues.
Activating glucokinase (GCK) mutations as a cause of medically responsive congenital hyperinsulinism: prevalence in children and characterisation of a novel GCK mutation.
Authors: Christesen Henrik B T , Tribble Nicholas D , Molven Anders , Siddiqui Juveria , Sandal Tone , Brusgaard Klaus , Ellard Sian , Njølstad Pål R , Alm Jan , Brock Jacobsen Bendt , Hussain Khalid , Gloyn Anna L 
Published: May 2008

ObjectiveActivating glucokinase (GCK) mutations are a rarely reported cause of congenital hyperinsulinism (CHI), but the prevalence of GCK mutations is not known.MethodsFrom a pooled cohort of 201 non-syndromic children with CHI from three European referral centres (Denmark, n=141; Norway, n=26; UK, n=34), 108 children had no KATP-channel (ABCC8/KCNJ11) gene abnormalities and were screened for GCK mutations. Novel GCK mutations were kinetically characterised.ResultsIn five patients, four heterozygous GCK mutations (S64Y, T65I, W99R and A456V) were identified, out of which S64Y was novel. Two of the mutations arose de novo, three were dominantly inherited. All the five patients were medically responsive. In the combined Danish and Norwegian cohort, the prevalence of GCK-CHI was estimated to be 1.2% (2/167, 95% confidence interval (CI) 0–2.8%) of all the CHI patients. In the three centre combined cohort of 72 medically responsive children without KATP-channel mutations, the prevalence estimate was 6.9% (5/72, 95% CI 1.1–12.8%). All activating GCK mutations mapped to the allosteric activator site. The novel S64Y mutation resulted in an increased affinity for the substrate glucose (S0.5 1.49±0.08 and 7.39±0.05 mmol/l in mutant and wild-type proteins respectively), extrapolating to a relative activity index of ∼22 compared with the wild type.ConclusionIn the largest study performed to date on GCK in children with CHI, GCK mutations were found only in medically responsive children who were negative for ABCC8 and KCNJ11 mutations. The estimated prevalence (∼7%) suggests that screening for activating GCK mutations is warranted in those patients.
Bone Augmentation With Autologous Periosteal Cells and Two Different Calcium Phosphate Scaffolds Under an Occlusive Titanium Barrier: An Experimental Study in Rabbits
Authors: Maréchal Marina , Eyckmans Jeroen , Schrooten Jan , Schepers Evert , Luyten Frank P. , van Steenberghe Daniel 
Published: May 2008

Background: This study used a tissue‐engineering approach, which combined autologous periosteal cells with a scaffold material, to promote bone augmentation under an occlusive titanium barrier that was placed on the skull of rabbits. Because the cell–matrix interaction is of key importance in tissue engineering, two different calcium phosphate–based scaffolds were seeded with autologous periosteal cells. One scaffold contained hydroxyapatite, tricalcium phosphate, and collagen; the other scaffold was a β‐tricalcium phosphate structure.Methods: The experiment involved 38 rabbits divided into five groups: the two different scaffolds with and without cells and a blood clot only. Prior to implantation, autologous periosteal cells were harvested from the tibia by stripping the periosteum. Cells were cultured, and 1 day before the implantation ∼20 million cells were collected and seeded onto the scaffolds. Two preformed dome–shaped full titanium barriers were placed subperiosteally onto the frontal and parietal bones of each rabbit. Before placement of the barriers, the different scaffolds, seeded with or without cells, were put on top of the skull. As a negative control, autologous blood was injected into the barriers. Histologic evaluation and histomorphometric analysis were performed after 12 weeks of undisturbed bone growth. Measurements involved the amounts of newly formed tissue and of new bone distinguishing between trabecular bone and osteoid.Results: No significant differences were found between the four treatment groups (scaffolds with or without cells). However, the amount of new bone tissue found underneath the titanium barriers with scaffolds was significantly higher (P <0.04) than with a blood clot only.Conclusion: A better understanding of the mode of action is required to optimize tissue‐engineering procedures before entering clinical applications.
Kindler Syndrome and Periodontal Disease: Review of the Literature and a 12‐Year Follow‐Up Case
Authors: Wiebe Colin B. , Petricca Giorgio , Häkkinen Lari , Jiang Guoqiao , Wu Chuanyue , Larjava Hannu S. 
Published: May 2008

Background: The association of aggressive periodontitis with Kindler syndrome was based on a single case in 1996 and later confirmed with a larger population. Since then, significant research has greatly increased our understanding of the molecular pathology of this disorder. We review recent advances in the molecular mechanisms of the syndrome and present a maintenance case report of a patient who has been followed in our clinic.Methods: A female patient who was diagnosed with Kindler syndrome and aggressive periodontitis at the age of 16 years has been followed and treated in our clinic for 12 years. Her main treatment has been maintenance therapy following her initial treatment and restorative work previously documented. Gingival biopsies obtained during the recent extraction of hopeless maxillary molars were used for histologic assessment of gingival tissue attachment apparatus and to isolate gingival fibroblasts. Reverse transcription‐polymerase chain reaction (RT‐PCR) was performed using these cells to confirm the lack of expression of kindlin‐1.Results: RT‐PCR showed the total loss of kindlin‐1 mRNA in cultured gingival fibroblasts, supporting the clinical diagnosis of Kindler syndrome. Tissue biopsies revealed atypical pocket epithelium. Maintenance therapy has been moderately successful. Teeth that were recently lost had a poor prognosis at the initial assessment. The patient's gingiva and oral mucosa continue to be fragile with episodes of sloughing and inflammation.Conclusions: Periodontitis in Kindler syndrome responds to maintenance therapy, but the gingiva and oral mucosa continue to display an abnormal appearance with white patches. Histologic findings suggest that the junctional epithelium in Kindler syndrome may be abnormal and could explain why these patients have periodontal disease. Attachment loss progressed around teeth with an initial guarded or poor prognosis. Teeth that started with a good or fair prognosis continue to have a fair prognosis. Limited dental implant treatment is being considered.
Dense Hydroxyapatite Inserted Into Postextraction Sockets: A Histologic and Histomorphometric 20‐Year Case Report
Authors: Mangano Carlo , Piattelli Adriano , Perrotti Vittoria , Iezzi Giovanna 
Published: May 2008

Background: The biologic behavior, i.e., the degradation of hydroxyapatite (HA) in the human body, is of relevance for clinicians. The present investigation is a long‐term (20‐year) histologic and histomorphometric evaluation of dense HA used in postextraction sockets.Methods: Dense HA particles were used in a patient in postextraction alveolar sockets to maintain the alveolar ridge height. The patient returned after 20 years for implant treatment. A ridge remodeling was necessary during implant insertion surgery, and the HA/bone tissue was harvested with bone‐cutting forceps from the canine and premolar area. The specimen was processed for histology and histomorphometry at the Implant Retrieval Centre, Dental School, University of Chieti‐Pescara.Results: Most of the particles (56%) were surrounded partially by bone, whereas some particles (39%) were surrounded completely. At higher magnification, bone was in close contact with the particles, and neither gaps nor fibrous tissues were present at the bone–biomaterial interface. Microscopically, the particles had a dense appearance. In only a few fields, it was possible to observe that the outer part of some particles had detached from the original particles' surface. Histomorphometry showed that bone represented 25.4% ± 3.2%, marrow spaces represented 41.3% ± 5.2%, and residual HA particles represented 38.1% ± 4.1%.Conclusions: Intimate binding between bone and HA particles was present after a long‐term implantation period (20 years). The fact that HA particles were surrounded closely by bone is very promising for the long‐term stability of the augmentation.
Effects of Periodontal Therapy on Glycemic Control and Inflammatory Markers
Authors: O'Connell Patricia A.A. , Taba Mario , Nomizo Auro , Foss Freitas Maria C. , Suaid Flavia A. , Uyemura Sergio A. , Trevisan Glauce L. , Novaes Arthur B. , Souza Sergio L.S. , Palioto Daniela B. , Grisi Marcio F.M. 
Published: May 2008

Background: Periodontitis, a complication of diabetes mellitus (DM), can induce or perpetuate systemic conditions. This double‐masked, placebo‐controlled study evaluated the effects of periodontal therapy (scaling and root planing [SRP]) on the serum levels of glycated hemoglobin (HbA1c) and on inflammatory biomarkers.Methods: Thirty subjects with type 2 DM and periodontitis were treated with SRP + placebo (SRP; N = 15) or with SRP + doxycycline (SRP+Doxy; N = 15), 100 mg/day, for 14 days. Clinical and laboratory data were recorded at baseline and at 3 months after treatment.Results: After 3 months, the reduction in probing depth was 0.8 mm for the SRP group (P <0.01) and 1.1 mm for the SRP+Doxy group (P <0.01) followed by a 0.9% (SRP; P = 0.17) and 1.5% (SRP+Doxy; P <0.01) reduction in HbA1c levels. A significant reduction in interleukin (IL)‐6; interferon‐inducible protein 10; soluble fas ligand; granulocyte colony‐stimulating factor; RANTES; and IL‐12 p70 serum levels were also verified (N = 30). To our knowledge, this is the first report on the effects of periodontal therapy on multiple systemic inflammatory markers in DM.Conclusions: Periodontal therapy may influence the systemic conditions of patients with type 2 DM, but no statistical difference was observed with the adjunctive systemic doxycycline therapy. Moreover, it is possible that the observed improvement in glycemic control and in the reduction of inflammatory markers could also be due to diet, which was not controlled in our study. Therefore, a confirmatory study with a larger sample size and controlled diet is necessary.
Locally Delivered Doxycycline During Supportive Periodontal Therapy: A 3‐Year Study
Authors: Bogren Anna , Teles Ricardo P. , Torresyap Gay , Haffajee Anne D. , Socransky Sigmund S. , Wennström Jan L. 
Published: May 2008

Background: Adjunctive locally delivered antibiotics during maintenance may favor the control of periodontal infections. This study evaluated the long‐term clinical and microbiologic effects of yearly locally delivered controlled‐release doxycycline as an adjunct to mechanical debridement.Methods: A total of 128 periodontal maintenance patients having at least four teeth with probing depth (PD) ≥5 mm were randomly assigned to local application of doxycycline gel at baseline and 1 and 2 years as an adjunct to mechanical debridement (test) or mechanical debridement only (control). Supportive periodontal therapy (mechanical debridement, polishing, and oral hygiene reinforcement) was provided every 6 months. Plaque, bleeding on probing (BOP), PD, and relative attachment level (RAL) were scored at baseline; 3 months; and 1, 2, and 3 years. Subgingival plaque samples were taken at each examination and analyzed for their content of 40 bacterial species. Data analyses were performed on an intention‐to‐treat basis with the subject as the statistical unit.Results: Significant reductions in BOP, PD, RAL, and the mean counts of a number of target species between baseline and 3 years were documented for both treatment groups, whereas plaque scores remained unchanged. A statistically significant difference in favor of the adjunctive doxycycline therapy was found between the two groups only at the 3‐month examination for BOP, PD, and RAL and for a minority of bacterial species at 2 years.Conclusion: Although short‐term effects on clinical parameters were found with the adjunctive use of locally delivered doxycycline, repeated applications annually had no clinical or microbiologic effects beyond those observed with mechanical debridement alone in maintenance patients.
Analysis of the Activity to Induce Toll‐Like Receptor (TLR)2‐ and TLR4‐Mediated Stimulation of Supragingival Plaque
Authors: Yoshioka Hidenobu , Yoshimura Atsutoshi , Kaneko Takashi , Golenbock Douglas T. , Hara Yoshitaka 
Published: May 2008

Background: The deleterious effects of the accumulation of supragingival plaque are well known, but the role of the proinflammatory property of supragingival plaque in periodontal diseases has not been completely elucidated. The aim of this study was to determine the relevance of Toll‐like receptor (TLR)2‐ and TLR4‐stimulating activity of supragingival plaque to periodontal parameters.Methods: We isolated 144 supragingival plaque samples and analyzed TLR2‐ and TLR4‐stimulating activity using genetically engineered Chinese hamster ovary reporter cells that express a reporter molecule upon activation of nuclear factor‐kappa B through TLR2 or TLR4. The numbers of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), and Streptococcus mutans cells in each plaque sample were determined by real‐time polymerase chain reaction.Results: The activity to induce TLR4‐mediated stimulation, but not TLR2‐mediated stimulation, was positively associated with the plaque score and bleeding on probing score of the teeth from which the plaque samples were taken. The activity to induce TLR2‐mediated stimulation, but not TLR4‐mediated stimulation, was negatively associated with probing depth and clinical attachment level. The ratio of TLR4‐/TLR2‐mediated stimulation was positively associated with all of those parameters. The number of P. gingivalis cells in each plaque sample was associated with the plaque score and clinical attachment level, but no strong association was observed between the ratio of examined bacteria in each plaque sample and the activity to induce TLR2‐ or TLR4‐mediated stimulation, except for a weak correlation between the ratio of A. actinomycetemcomitans cells and the activity to induce TLR4‐mediated stimulation.Conclusion: The TLR2‐ and TLR4‐stimulating activity of supragingival plaque is associated with clinical parameters for gingivitis and periodontitis.
In Vitro Characterization of the Cytokine Profile of the Epithelial Cell Rests of Malassez
Authors: Ohshima Mitsuhiro , Yamaguchi Yoko , Micke Patrick , Abiko Yoshimitsu , Otsuka Kichibee 
Published: May 2008

Background: The epithelial cell rests of Malassez (ERM) are an integral part of the periodontal ligament and are considered to play an important role in dental pathology. Surprisingly, this cell type is poorly described and is often disregarded in the context of periodontal research. The aim of this study was to establish primary cell cultures of human ERM, characterize the cytokine profile, and compare it to other periodontal cell entities.Methods: ERM‐derived epithelial cells were isolated from the periodontal ligament of three subjects. A cytokine antibody array, including 120 cytokines in two membranes, was used to determine the cytokine profile of conditioned medium from the ERM‐derived epithelial cells. The results were compared to those of gingival epithelial cells and periodontal ligament fibroblasts.Results: ERM‐derived epithelial cells expressed 29 of 120 cytokines in significant amounts, including cytokines, chemokines, growth factors, and related proteins, such as interleukin (IL)‐1, −6, −8, and −10; granulocyte macrophage‐colony stimulating factor; monocyte chemoattractant protein (MCP)‐1, −2, and −3; amphiregulin; glial‐derived neurotrophic factor; vascular endothelial growth factor; and insulin‐like growth factor binding protein‐2. The cytokine profile of ERM cells was similar to that of gingival epithelial cells but strikingly different from the profile of periodontal ligament fibroblasts.Conclusions: The results indicated that, via paracrine secretion of a variety of soluble factors, the ERM cells actively take part in the homeostasis of the periodontium. Therefore, future research on the pathophysiology of periodontal tissue should include this often overlooked cell type.
Growth and Elemental Accumulation by Canola on Soil Amended with Coal Fly Ash
Authors: Yunusa I. A. M. , Manoharan V. , DeSilva D. L. , Eamus D. , Murray B. R. , Nissanka S. P. 
Published: May 2008

AbstractTo explore the agronomic potential of an Australian coal fly ash, we conducted two glasshouse experiments in which we measured chlorophyll fluorescence, CO2 assimilation (A), transpiration, stomatal conductance, biomass accumulation, seed yield, and elemental uptake for canola (Brassica napus) grown on soil amended with an alkaline fly ash. In Experiment 1, application of up to 25 Mg/ha of fly ash increased A and plant weight early in the season before flowering and seed yield by up to 21%. However, at larger rates of ash application A, plant growth, chlorophyll concentration, and yield were all reduced. Increases in early vigor and seed yield were associated with enhanced uptake of phosphorus (P) by the plants treated with fly ash. Fly ash application did not influence accumulation of B, Cu, Mo, or Zn in the stems at any stage of plant growth or in the seed at harvest, except Mo concentration, which was elevated in the seed. Accumulation of these elements was mostly in the leaves, where concentrations of Cu and Mo increased with any amount of ash applied while that of B occurred only with ash applied at 625 Mg/ha. In Experiment 2, fly ash applied at 500 Mg/ha and mixed into the whole 30 cm soil core was detrimental to growth and yield of canola, compared with restricting mixing to 5 or 15 cm depth. In contrast, application of ash at 250 Mg/ha with increasing depth of mixing increased A and seed yield. We concluded that fly ash applied at not more than 25 Mg/ha and mixed into the top 10 to 15 cm of soil is sufficient to obtain yield benefits.
Pesticide Fate and Transport throughout Unsaturated Zones in Five Agricultural Settings, USA
Authors: Hancock Tracy C. , Sandstrom Mark W. , Vogel Jason R. , Webb Richard M.T. , Bayless E. Randall , Barbash Jack E. 
Published: May 2008

AbstractPesticide transport through the unsaturated zone is a function of chemical and soil characteristics, application, and water recharge rate. The fate and transport of 82 pesticides and degradates were investigated at five different agricultural sites. Atrazine and metolachlor, as well as several of the degradates of atrazine, metolachlor, acetochlor, and alachlor, were frequently detected in soil water during the 2004 growing season, and degradates were generally more abundant than parent compounds. Metolachlor and atrazine were applied at a Nebraska site the same year as sampling, and focused recharge coupled with the short time since application resulted in their movement in the unsaturated zone 9 m below the surface. At other sites where the herbicides were applied 1 to 2 yr before sampling, only degradates were found in soil water. Transformations of herbicides were evident with depth and during the 4‐mo sampling time and reflected the faster degradation of metolachlor oxanilic acid and persistence of metolachor ethanesulfonic acid. The fraction of metolachlor ethanesulfonic acid relative to metolachlor and metolachlor oxanilic acid increased from 0.3 to >0.9 at a site in Maryland where the unsaturated zone was 5 m deep and from 0.3 to 0.5 at the shallowest depth. The flux of pesticide degradates from the deepest sites to the shallow ground water was greatest (3.0–4.9 μmol m−2 yr−1) where upland recharge or focused flow moved the most water through the unsaturated zone. Flux estimates based on estimated recharge rates and measured concentrations were in agreement with fluxes estimated using an unsaturated‐zone computer model (LEACHM).
Soil Sulfur Amendments Suppress Selenium Uptake by Alfalfa and Western Wheatgrass
Authors: Mackowiak C. L. , Amacher M. C. 
Published: May 2008

AbstractSelenium (Se) is a potential soil contaminant in many parts of the world where it can pose a health risk to livestock and wildlife. Phosphate ore mining in Southeast Idaho has resulted in numerous waste rock dumps revegetated with forages to stabilize the dumps and support grazing. Alfalfa (Medicago sativa L.), smooth brome (Bromus inermis Leyss.), and western wheat grass [Pascopyrum smithii (Rydb.) A. Löve] are the dominant forage species on these lands. To demonstrate the feasibility of using sulfur (S) as a soil amendment to restrict plant Se uptake, 3 kg pots containing 50:50 w/w soil and waste shale were uniformly mixed with 0, 0.5, 1.0, or 2.0 Mg ha−1 S as either elemental S or gypsum. Pots were seeded with alfalfa or western wheat grass. Dry mass and tissue Se were monitored over several clippings. Soils were sampled at the conclusion of the study and analyzed for water‐soluble, oxalate‐extractable, and total Se. Sulfur amendments as either elemental S or gypsum at 1.0 Mg ha−1 or greater equally suppressed Se uptake over 60% in both forage species. Alfalfa accumulated more Se than western wheat grass. Plant removal via successive clippings resulted in lower tissue Se accumulation over time than the use of S soil amendments alone. Alfalfa‐planted soils contained lower water‐soluble and oxalate‐extractable Se than did the non‐planted controls while western wheat grass‐planted soils contained lower water‐soluble Se. Applying S to these shale‐based soils may be an economically viable option for treating Se‐impacted, revegetated lands.