bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of Gating and Rundown of HCN Hyperpolarization-activated Channels by Exogenous and Endogenous PIP2
Authors: Pian Phillip , Bucchi Annalisa , Robinson Richard B. , Siegelbaum Steven A.
Published: October 2006

The voltage dependence of activation of the HCN hyperpolarization-activated cation channels is shifted in inside-out patches by −40 to −60 mV relative to activation in intact cells, a phenomenon referred to as rundown. Less than 20 mV of this hyperpolarizing shift can be due to the influence of the canonical modulator of HCN channels, cAMP. Here we study the role of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) in HCN channel rundown, as hydrolysis of PI(4,5)P2 by lipid phosphatases is thought to underlie rundown of several other channels. We find that bath application of exogenous PI(4,5)P2 reverses the effect of rundown, producing a large depolarizing shift in HCN2 activation. A synthetic short chain analogue of PI(4,5)P2, dioctanoyl phosphatidylinositol 4,5-bisphosphate, shifts the HCN2 activation curve to more positive potentials in a dose-dependent manner. Other dioctanoyl phosphatidylinositides with one or more phosphates on the lipid headgroup also shift activation, although phosphatidylinositol (PI) is ineffective. Several lines of evidence suggest that HCN2 is also regulated by endogenous PI(4,5)P2: (a) blockade of phosphatases slows the hyperpolarizing shift upon patch excision; (b) application of an antibody that binds and depletes membrane PIP2 causes a further hyperpolarizing shift in activation; (c) the shift in activation upon patch excision can be partially reversed by MgATP; and (d) the effect of MgATP is blocked by wortmannin, an inhibitor of PI kinases. Finally, recordings from rabbit sinoatrial cells demonstrate that diC8 PI(4,5)P2 delays the rundown of native HCN currents. Thus, both native and recombinant HCN channels are regulated by PI(4,5)P2.
Modelling population persistence on islands: mammal introductions in the New Zealand archipelago
Authors: Duncan Richard P , Forsyth David M
Published: October 2006

Islands are likely to differ in their susceptibility to colonization or invasion due to variation in factors that affect population persistence, including island area, climatic severity and habitat modification. We tested the importance of these factors in explaining the persistence of 164 introductions of six mammal species to 85 islands in the New Zealand archipelago using survival analysis and model selection techniques. As predicted by the theory of stochastic population growth, extinction risk was the greatest in the period immediately following introduction, declining rapidly to low probability by
ca
25 years. This suggests that initially small populations were at greatest risk of extinction and that populations which survived for 25 years were likely to persist subsequently for much longer. Islands in the New Zealand archipelago become colder and windier with increasing latitude, and the probability of mammal populations persisting on islands declined steeply with increasing latitude. Hence, our results suggest that climatic suitability was an important determinant of the outcome of these invasions. The form of the relationship between latitude and persistence probability differed among species, emphasizing that the outcome of colonization attempts is species-environment specific.
Sequence diversity of the mucABD locus in Pseudomonas aeruginosa isolates from patients with cystic fibrosis
Authors: Bragonzi Alessandra , Wiehlmann Lutz , Klockgether Jens , Cramer Nina , Worlitzsch Dieter , Döring Gerd , Tümmler Burkhard
Published: October 2006

ThemucAgene of themucoperon, which is instrumental in the control of the biosynthesis of the exopolysaccharide alginate, is a hotspot of mutation inPseudomonas aeruginosa, a micro-organism that chronically colonizes the airways of individuals with cystic fibrosis (CF). ThemucA,mucBandmucDgenes were sequenced in nine environmental isolates from aquatic habitats, and in 37P. aeruginosastrains isolated from 10 patients with CF, at onset or at a late stage of chronic airway colonization, in order to elucidate whether there was any association between mutation and background genotype. The 61 identified single nucleotide polymorphisms (SNPs) segregated into 18mucABDgenotypes. Acquired andde novostopmucAmutations were present in 14 isolates (38 %) of fivemucABDgenotypes. ΔG430 was the most frequent and recurrentmucAmutation detected in four genotypes. The classification of strains bymucABDgenotype was generally concordant with that by genome-wide SpeI fragment pattern or multilocus SNP genotypes. The exceptions point to intragenic mosaicism and interclonal recombination as major forces for intraclonal evolution at themucABDlocus.
Inhibition of Cdc42-dependent signalling in Saccharomyces cerevisiae by phosphatase-dead SigD/SopB from Salmonella typhimurium
Authors: Rodríguez-Escudero Isabel , Rotger Rafael , Cid Víctor J. , Molina María
Published: October 2006

Heterologous expression of bacterial virulence factors inSaccharomyces cerevisiaeis a feasible approach to study their molecular function. The authors have previously reported that theSalmonella typhimuriumSigD protein, a phosphatidylinositol phosphatase involved in invasion of the host cell, inhibits yeast growth, presumably by depleting an essential pool of phosphatidylinositol 4,5-bisphosphate, and also that a catalytically inactive version, SigDR468A, was able to arrest growth by a different mechanism that involved disruption of the actin cytoskeleton. This paper describes marked differences between the phenotypes elicited by expression of SigD and SigDR468Ain yeast. First, expression of SigDR468Acaused accumulation of large unbudded cells and loss of septin organization, while SigD expression caused none of these effects. Second, growth inhibition by SigDR468Awas mediated by a cell cycle arrest in G2 dependent on the Swe1 morphogenetic checkpoint, but SigD-induced growth inhibition was cell cycle independent. And third, SigD caused strong activation of the yeast MAP kinase Slt2, whereas SigDR468Arather inactivated another MAP kinase, Kss1. In a screen for suppressors of SigDR468A-induced growth arrest by overexpression of a yeast cDNA library, the Cdc42 GTPase was isolated. Furthermore, SigDR468Awas co-purified with Cdc42 from yeast lysates. It is concluded that theSalmonellaSigD protein deprived of its phosphatase activity is able to disrupt yeast morphogenesis by interfering with Cdc42 function, opening the possibility that the SigD N-terminal region might directly modulate small GTPases from the host during infection.
Rapid diversification of colouration among populations of a poison frog isolated on sky peninsulas in the central cordilleras of Peru
Authors: Roberts Jennifer L. , Brown Jason L. , Schulte Rainer , Arizabal Wilfredo , Summers Kyle
Published: October 2006

Aim  Comparison of Epipedobates bassleri (Myers, 1987), which occurs on high‐altitude mountain ridges (‘sky peninsulas’) in the Andean transition zone and demonstrates high levels of divergence in colouration among populations, and Epipedobates hahneli (Schulte, 1999), which occurs throughout the lowland regions of the Amazon basin and is morphologically conserved, using phylogenetic analysis of mitochondrial sequence data and comparison of colour pattern.

Location  Central cordilleras of Peru (near Tarapoto, San Martin).

Methods  DNA was extracted from individuals of E. bassleri from the central cordilleras of Peru, and from individuals of E. hahneli from across Peru. The cytochrome b mitochondrial gene region was amplified and sequenced for individuals of each species, and phylogenetic analysis was carried out using Bayesian inference. Genetic distances among populations and geographic distances of each species were examined and compared using Mantel tests. Parametric bootstrapping was used to test the monophyly of E. bassleri.

Results  Epipedobates bassleri formed a well‐supported monophyletic group and showed higher levels of genetic divergence among populations than was shown among populations of E. hahneli from the same region. Distinct clades representing different geographic regions were recovered for E. hahneli. Levels of divergence among more geographically distant populations of E. hahneli were higher than levels of divergence among E. bassleri populations. We found a significant correlation between genetic divergence and geographic distance as measured along a 1000‐m contour line, but not as measured by direct routes (crossing putative biogeographical barriers).

Main conclusions  Levels of genetic divergence were higher among populations of morphologically conservative E. hahneli than among populations of morphologically variable E. bassleri, suggesting rapid divergence in colouration among populations of E. bassleri. These patterns support previous arguments concerning the role of the montane transition zone between the high mountains and lowlands in divergence and speciation. High levels of both genetic and phenotypic divergence among populations of E. bassleri indicate that ecological or behavioural factors may be responsible for the high levels of colour variation seen among E. bassleri, but not among E. hahnleli, populations.
Chloroplast DNA variation in the Turnera sidoides L. complex (Turneraceae): biogeographical implications
Authors: Speranza P. R. , Seijo J. G. , Grela I. A. , Solís Neffa V. G.
Published: October 2006

Aim  To analyse the current geographical structure of chloroplast DNA variation in the Turnera sidoides L. complex in order to establish historical biogeographical hypotheses for the mid‐latitude South American lowlands. During the Quaternary, the climate shifted from tropical humid to cold dry, and the vegetation cover has not been stable. The consequences of these processes on the current distribution of the vegetation of this area have received very little attention.

Location  The mid‐latitude South American lowlands extend between c. 20 and 40°S and include Uruguay, northern, central and eastern Argentina, southern Brazil, and parts of southern Paraguay and Bolivia. They are surrounded by higher‐elevation systems.

Methods  Turnera sidoides is a well‐studied polyploid complex of perennial rhizomatous herbs occurring throughout the area of interest. We analysed 321 individuals from 79 populations of the five recognized subspecies. We also included progenies from artificial crosses in order to analyse chloroplast inheritance. After screening sequences for four non‐coding chloroplast DNA regions, the trnL–trnF spacer was selected to characterize the collection.

Results  Three haplotypes can be easily identified, with each differing from the others in two independent characters. A clear geographic structure is revealed when haplotypes are plotted for the complex as a whole regardless of subspecies and cytotype. Three distinct regions can be identified.

Main conclusions  We propose three putative refugial areas for the Turnera sidoides complex, which are associated with the orographical systems of the region. Ravines and slopes in the Haedo Cuchilla system in northern Uruguay, the elevations of the western side of the area in Argentina, and the eastern Serranías system in south‐eastern Uruguay may each have served as refugia in which the A, B and C haplotypes became fixed during the drier climatic phases. Biogeographical patterns in the area covered by T. sidoides, particularly east of the Uruguay River, have not previously been analysed from a historical perspective.
Footbath acaricide treatment to control cattle infestation by the tick Amblyomma variegatum
Authors: STACHURSKI F. , LANCELOT R.
Published: October 2006

Abstract Previous studies have shown that about 90% of adult Amblyomma variegatum Fabricius (Acari: Ixodidae) picked up daily by grazing cattle are still attached to the interdigital areas in the evening, when the animals return from pasture. It was therefore postulated that a targeted treatment, designed to kill the ticks attached to the feet, would limit infestation of the predilection sites. Footbaths filled with various pyrethroid formulations were used over 3 years, at the beginning of the rainy season (from mid‐May to the end of July), to assess the efficacy of such a control method. It proved efficient in preventing the ticks from attaching to the predilection sites. Although five to 12 A. variegatum adults attached to each treated animal daily, and although the tick burden of the predilection sites of control cattle increased each day by four to 10 ticks, the average infestation of the predilection sites of treated cattle that were initially highly infested (over 100 ticks/animal) continuously decreased to reach a level of about 10–30 ticks/animal after 6–8 weeks of treatment. In herds with a lower initial tick burden (40–70 ticks/animal) this level was obtained within 2–3 weeks and the mean infestation subsequently remained consistently low. Footbath treatment carried out every other day during the adult peak infestation period should therefore greatly limit losses due to ticks. This method was appreciated by traditional livestock farmers, essentially because it is not time‐consuming and because it requires only c. 200 mL aqueous formulation per animal at each passage. The cost of the acaricide needed to treat one animal during the peak infestation period was assessed at c. € 0.20. This control method might also have an impact on some species of tsetse flies and mosquitoes, thereby contributing to trypanosomiasis and malaria control.
Classification of feline intraocular neoplasms based on morphology, histochemical staining, and immunohistochemical labeling
Authors: Grahn Bruce H. , Peiffer Robert L. , Cullen Cheryl L. , Haines Deborah M.
Published: October 2006

The objectives of this study were to evaluate morphologic, histochemical, and immunohistochemical characteristics of well‐differentiated and anaplastic intraocular neoplasms of cats, and to develop a diagnostic algorithm for, and investigate the association of ruptured lenses with these neoplasms. Seventy‐five feline globes with intraocular neoplasms were stained with hematoxylin and eosin and examined by light microscopy. Morphologic diagnoses included 33 intraocular sarcomas, 17 diffuse iris melanomas, 15 lymphosarcomas, three ciliary adenomas, one metastatic carcinoma, and six undifferentiated intraocular neoplasms. Sections of these globes were then stained with periodic acid Schiff (PAS), and immunohistochemical (IHC) labels for various cellular markers. Histochemical staining and IHC labeling confirmed cellular differentiation in 73/75 neoplasms but was discordant with morphologic diagnoses in 8/75. These included four neoplasms morphologically diagnosed as lymphosarcomas but which expressed differentiation antigens consistent with melanoma (n = 3) or ciliary adenocarcinoma (n = 1), and four tumors morphologically diagnosed as intraocular sarcomas that expressed differentiation antigens for melanoma (n = 2), metastatic carcinoma (n = 1), or remained undifferentiated (n = 1). Immunohistochemical labeling suggested a diagnosis in 5/6 morphologically undifferentiated neoplasms including one intraocular sarcoma, two diffuse iridal melanomas, and two ciliary adenocarcinomas. Based upon morphologic, histochemical, and IHC characterization, ruptured lens capsules were detected in 28/30 intraocular sarcomas, 3/24 diffuse iris melanomas and 1/11 lymphosarcomas, but not in ciliary epithelial neoplasms, metastatic carcinomas, or undifferentiated intraocular neoplasms. An algorithm is provided that facilitates stain and IHC label selection for differentiating anaplastic intraocular feline neoplasms.
Amniotic membrane transplantation for corneal surface reconstruction after excision of corneolimbal squamous cell carcinomas in nine horses
Authors: Ollivier F. J. , Kallberg M. E. , Plummer C. E. , Barrie K. P. , O’Reilly S. , Taylor D. P. , Gelatt K. N. , Brooks D. E.
Published: October 2006

Objective The purpose of this study was to evaluate the usefulness and effectiveness of permanent amniotic membrane transplantation as an adjunctive treatment to superficial keratectomy alone or combined with strontium‐90 irradiation for treatment of equine corneolimbal squamous cell carcinoma (SCC) to decrease corneal scarring and recurrence rate.

Study The retrospective case study included 11 horses (n = 12 eyes) diagnosed and treated for ocular SCC that involved the limbus and cornea. Nine of those horses (n = 9 eyes) were treated between 2002 and 2006, with superficial lamellar keratectomy alone or combined with strontium‐90 irradiation and followed by placement of a permanent amniotic membrane graft in the surgical defect. The level of scarring (i.e. the clarity of the cornea) resulting with the use of amniotic membrane was subjectively compared to cases where a permanent bulbar conjunctival graft was performed following keratectomy combined with strontium‐90 irradiation or cryotherapy (n = 3 eyes). Recurrence was defined as the postoperative and postirradiation regrowth of SCC in the same site and globe.

Results The nine horses that received an amniotic membrane graft after keratectomy alone or combined with irradiation showed a minimal level of scarring in a cornea that regained a greater transparency in comparison to the horses that were treated with a bulbar conjunctival graft. All of the horses that received an amniotic membrane graft had 226 ± 218 days of follow‐up without tumor recurrence (mean ± SD), ranging from 21 days to 778 days.

Conclusions The combination of superficial keratectomy alone or associated with β‐irradiation and permanent amniotic membrane transplantation is an effective treatment of corneal or corneolimbal SCC in horses. The placement of an amniotic membrane material represents an alternative surgical procedure to bulbar conjunctival grafts, especially if there is a lack of bulbar conjunctiva tissue available after tumor resection or if a particularly large corneal resection is necessary. The amniotic membrane is incorporated into the corneal defect and seems to create noticeably much less scarring than a corneal defect covered by bulbar conjunctiva.
Is Fiscal Policy Sustainable in Developing Economies?
Authors: Ghatak Subrata , Sánchez‐Fung José R.
Published: October 2006

This paper investigates fiscal policy sustainability in Peru, the Philippines, South Africa, Thailand, and Venezuela using competing methodologies. Standard unit roots and cointegration analyses do not endorse the validity of the intertemporal budget constraint. In contrast, to varying degrees across countries, alternative testing employing a fiscal policy reaction function indicates sustainability defined as surplus adjustments in response to higher debt‐to‐income ratios. Corresponding debt‐dynamics analyses show that corrective measures were put in place to revert non‐sustainable trends in government debt. However, ancillary variables in the debt modeling produce statistically weak evidence of procyclical fiscal behavior in the Latin American countries.
New Child–Caregiver Attachment Relationships: Entering Childcare When the Caregiver Is and Is Not an Ethnic Match
Authors: Howes Carollee , Shivers Eva Marie
Published: October 2006

The goal of the research reported in this article was to examine the process of forming attachment to caregivers in children new to childcare. We examined child and adult behaviors and the adult's perception of the child at entry, and the ethnic/racial match between the child and caregiver as predictors of attachment relationship quality measured six months later. Adult perceptions of the child did not predict attachment security. Children who did not share an ethnic heritage with their caregiver and had conflictual interactions with her at entry or at Time 2 had the lowest attachment security at Time 2. Children who shared an ethnic heritage with their caregivers and either did or did not engage in conflictual interaction and children who did not share an ethnic heritage and had low conflict at entry and at Time 2 were similar in security.
Media Exposure, Aggression and Prosocial Behavior During Early Childhood: A Longitudinal Study
Authors: Ostrov Jamie M. , Gentile Douglas A. , Crick Nicki R.
Published: October 2006

Preschool children (N = 78) enrolled in multi‐informant, multi‐method longitudinal study were participants in a study designed to investigate the role of media exposure (i.e., violent and educational) on concurrent and future aggressive and prosocial behavior. Specifically, the amount of media exposure and the nature of the content was used to predict concurrent and future physical, verbal and relational aggression as well as prosocial behavior for girls and boys. This two‐year longitudinal study found that media exposure predicted various subtypes of aggression and prosocial behavior. These findings are qualified by the gender of the focal child. That is, parental reports of media exposure were associated with relational aggression for girls and physical aggression for boys at school. Ways in which these findings extend our understanding of the role of media during early childhood are discussed.
Appearance Culture in Nine‐ to 12‐Year‐Old Girls: Media and Peer Influences on Body Dissatisfaction
Authors: Clark Levina , Tiggemann Marika
Published: October 2006

Little research has investigated sociocultural factors in the development of body dissatisfaction in preadolescent girls. This study examined the combined influence of media and peer factors. The participants were 100 girls aged nine to 12 years. The girls completed questionnaire measures of media exposure (television and magazines), peer influences (appearance norms, appearance conversations), internalization and body dissatisfaction. Their height and weight were also measured. About half (49 percent) of the girls displayed a desire to be thinner. The influence of sociocultural factors was confirmed in addition to biological determinants, such as body mass index. Their exposure to appearance‐focused media was not directly related to their body dissatisfaction, but was indirectly related via their conversations about appearance among peers. The path analysis showed that peer appearance conversations demonstrated a significant relationship with internalization of thin ideals, which was, in turn, significantly related to body dissatisfaction. Like their adolescent counterparts, preadolescent girls are also exposed to appearance ideals presented in the media and manifested among peers. The results provided evidence for the existence of an ‘appearance culture’ consisting of interrelated media and peer influences among girls as young as nine to 12 years of age.
Lessons from leeches: a call for DNA barcoding in the lab
Authors: Bely Alexandra E. , Weisblat David A.
Published: October 2006

SUMMARY
Many evolution of development labs study organisms that must be periodically collected from the wild. Whenever this is the case, there is the risk that different field collections will recover genetically different strains or cryptic species. Ignoring this potential for genetic variation may introduce an uncontrolled source of experimental variability, leading to confusion or misinterpretation of the results. Leeches in the genus Helobdella have been a workhorse of annelid developmental biology for 30 years. Nearly all early Helobdella research was based on a single isolate, but in recent years isolates from multiple field collections and multiple sites across the country have been used. To assess the genetic distinctness of different isolates, we obtained specimens from most Helobdella laboratory cultures currently or recently in use and from some of their source field sites. From these samples, we sequenced part of the mitochondrial gene cytochrome oxidase I (COI). Sequence divergences and phylogenetic analyses reveal that, collectively, the Helobdella development community has worked on five distinct species from two major clades. Morphologically similar isolates that were thought to represent the same species (H. robusta) actually represent three species, two of which coexist at the same locality. Another isolate represents part of a species complex (the “H. triserialis” complex), and yet another is an invasive species (H. europaea). We caution researchers similarly working on multiple wild‐collected isolates to preserve voucher specimens and to obtain from these a molecular “barcode,” such as a COI gene sequence, to reveal genetic variation in animals used for research.
Conservation and divergence of Bmp2a, Bmp2b, and Bmp4 expression patterns within and between dentitions of teleost fishes
Authors: Wise Sarah B. , Stock David W.
Published: October 2006

SUMMARY
The diversity of tooth location in teleost fishes provides an excellent system for comparing genetic divergence between teeth in different species (phylogenetic homologs) with divergence between teeth within one species (iterative homologs). We have chosen to examine the expression of three members of the bone morphogenetic protein (Bmp) family because they are known to play multiple roles in tooth development and evolution in tetrapod vertebrates. We characterized expression of Bmp2a, Bmp2b, and Bmp4 during the development of oral and pharyngeal dentitions in three species of teleost fishes, the zebrafish (Danio rerio), Mexican tetra (Astyanax mexicanus), and Japanese medaka (Oryzias latipes). We found that expression in teleosts is generally highly conserved, with minor differences found among both iteratively homologous and phylogenetically homologous teeth. Expression of orthologous genes differs in several ways between the teeth of teleost fishes and those of the mouse, but between these vertebrate groups the summed expression pattern of Bmp genes is highly conserved. Significantly, the toothless oral region of the zebrafish lacks Bmp expression domains found in teleosts with oral teeth, implicating these genes in evolutionary tooth loss. We conclude that Bmp expression has been largely conserved in vertebrate tooth development over evolutionary time, and that loss of Bmp expression is correlated with region‐specific loss of the dentition in a major group of fishes.
Endogenous thyroid hormone synthesis in facultative planktotrophic larvae of the sand dollar Clypeaster rosaceus: implications for the evolutionary loss of larval feeding
Authors: Heyland Andreas , Reitzel Adam M. , Price David A. , Moroz Leonid L.
Published: October 2006

SUMMARY
Critical roles of hormones in metamorphic life history transitions are well documented in amphibians, lampreys, insects, and many plant species. Recent evidence suggests that thyroid hormones (TH) or TH‐like compounds can regulate development to metamorphosis in echinoids (sea urchins, sand dollars, and their relatives). Moreover, previous research has provided evidence for endogenous hormone synthesis in both feeding and nonfeeding echinoderm larvae. However, the mechanisms for endogenous synthesis remain largely unknown. Here, we show that facultatively planktotrophic larvae (larvae that reach metamorphosis in the absence of food but have the ability to feed) from the subtropical sea biscuit Clypeaster rosaceus can synthesize thyroxine endogenously from incorporated iodine (I125). When treated with the goitrogen thiourea (a peroxidase inhibitor), iodine incorporation, thyroxine synthesis, and metamorphosis are all blocked in a dose‐dependent manner. The inhibitory effect on metamorphosis can be rescued by administration of exogenous thyroxine. Finally, we demonstrate that thiourea induces morphological changes in feeding structures comparable to the phenotypic plastic response of larval structures to low food conditions, further supporting a signaling role of thyroxine in regulating larval morphogenesis and phenotypic plasticity. We conclude that upregulation of endogenous hormone synthesis might have been associated with the evolution of nonfeeding development, subsequently leading to morphological changes characteristic of nonfeeding development.
Recent Advances and New Challenges in Child Maltreatment Research, Practice, and Policy: Previewing the Issues
Authors: Bottoms Bette L. , Quas Jodi A.
Published: October 2006

Few issues are of such grave importance to society and to the science and practice of psychology as child maltreatment. Our goal in editing this issue of JSI was to inform scientists across various sub‐fields of psychology about the most current knowledge in the field of child maltreatment, broadly defined. The authors of the articles have gone further, pushing past the edge of current knowledge and setting aggressive agendas for future empirical and policy‐relevant work. We believe that the result will be enriched future research, practice, policy, and law, and in turn, the increased well‐being of children and their families.
Developing Evidence‐Based Interventions for Foster Children: An Example of a Randomized Clinical Trial with Infants and Toddlers
Authors: Dozier Mary , Peloso Elizabeth , Lindhiem Oliver , Gordon M. Kathleen , Manni Melissa , Sepulveda Sandra , Ackerman John , Bernier Annie , Levine Seymour
Published: October 2006

Children who enter foster care have usually experienced maltreatment as well as disruptions in relationships with primary caregivers. These children are at risk for a host of problematic outcomes. However, there are few evidence‐based interventions that target foster children. This article presents preliminary data testing the effectiveness of an intervention, Attachment and Biobehavioral Catch‐up, to target relationship formation in young children in the foster care system. Children were randomly assigned to the experimental intervention that was designed to enhance regulatory capabilities or to a control intervention. In both conditions, the foster parents received in‐home training for 10 weekly sessions. Post‐intervention measures were collected 1 month following the completion of the training. Outcome measures included children's diurnal production of cortisol (a stress hormone), and parent report of children's problem behaviors. Children in the experimental intervention group had lower cortisol values than children in the control intervention. Also, the experimental intervention parents reported fewer behavior problems for older versus younger foster children. Results provide preliminary evidence of the effectiveness of an intervention that targets children's regulatory capabilities and serve as an example of how interventions can effectively target foster children in the child welfare system.
Measuring State Welfare Policy Changes: Why Don't They Explain Caseload and Employment Outcomes?*
Authors: Cadena Brian , Danziger Sheldon , Seefeldt Kristin
Published: October 2006

Objectives. Since the implementation of the 1996 Personal Responsibility and Work Opportunity Reconciliation Act, many analysts have attempted to measure the effects of new state welfare policies, particularly work requirements, sanctions, and time limits, on the Act's key goals—reducing cash assistance caseloads and increasing employment among single mothers. De Jong et al. present new measures of state policy variations, but they do not attempt to evaluate the relationships between these measures and welfare reform outcomes. For their analysis to be meaningful, it should contribute to a better understanding of cross‐state variations in caseload declines and increased employment among single mothers.

Methods. We first raise conceptual questions about the extent to which their measures are meaningful in a policy sense. We then present analyses of Current Population Survey data.

Results. We find that differences in the De Jong et al. stringency measures (factor scores) are not significantly correlated with differences in welfare reform outcomes by state.
Forensic Science Does Not Start in the Lab: The Concept of Diagnostic Field Tests*
Authors: Almog Joseph
Published: October 2006

ABSTRACT: An attempt to improve an analytical system can focus either on the actual processing or on the input. In forensic science, much emphasis has been placed on improving laboratory procedures, as though the input is already the best that can be obtained. Means of improving the basic input have gained much less attention. Yet, it must be agreed that even the best laboratory cannot gain from an item more than has been contained in it when it arrived from the field. The detection of latent materials at the crime scene by physical or chemical techniques and the diagnostic examination of material already discovered belong to the concept of diagnostic field tests. This group also includes “mapping” for the presence of certain materials, such as latent fingerprints through the distribution of amino acids on the surface. These tests are conducted outside the laboratory, without sophisticated instrumentation, at the crime scene, the suspect's home, or elsewhere. A significant advantage of the use of diagnostic field tests is the ability to deal with “dissipating evidence” such as gunshot residue or explosive traces on the hands of suspects. If time is lost, there is a risk of losing such evidence, which is liable to deteriorate rapidly. In my presentation, I will discuss older and some newly developed forensic field tests, with specific emphasis on the Israeli experience.
Simplified Methods of Implant Treatment in the Edentulous Lower Jaw. A Controlled Prospective Study. Part I: One‐Stage versus Two‐Stage Surgery
Authors: Engquist Bo , Åstrand Per , Anzén Bengt , Dahlgren Simon , Engquist Eva , Feldmann Hartmut , Karlsson Ulf , Gunnar Nord Per , Sahlholm Sten , Svärdström Pia
Published: October 2006

Background: The original protocol for Brånemark System implants in the mandible was a two‐stage procedure with 3 months healing time. With five or six implants and a cast framework of gold, the treatment is rather expensive, and simplified methods would be desirable.

Purpose: The goal of this controlled serial study was to investigate the outcome of a simplified procedure with one‐stage surgery, four Brånemark implants, shortened healing time, and a new titanium‐acrylic fixed full prosthesis.

Materials and Methods: Eighty‐two patients were treated in three different groups at two specialist centers. All patients were provided with four implants, loaded with a Procera All‐in‐One bridge (Nobel Biocare, Gothenburg, Sweden) after 12 weeks. In group A (n = 30), one‐stage surgery was combined with two‐piece implants. In group B (n = 30), the control group, two‐stage surgery and two‐piece implants were used. In group C (n = 22), one‐stage surgery was combined with one‐piece implants. Marginal bone level was rated from radiographs at implant insertion, at baseline, and after 1 year.

Results: The survival rate after 1 year for group A was 93.3%; group B, 97.5%; and group C, 93.2%. The differences were not statistically significant. Between fixture insertion and baseline, the average bone loss for group A was 1.2 mm; group B, 1.3 mm; and group C, 1.3 mm. No complications in the form of bridge loosening or acrylic fractures were recorded during the first year.

Conclusions: The survival rates and the marginal bone changes did not differ significantly between the one‐stage groups and the control group. The survival rate and the marginal bone changes were similar for one‐piece and two‐piece implants. Four implants were sufficient to support full fixed prostheses in the mandibles. The Procera All‐in‐One bridges proved to be of high quality, and no complications were experienced.
Stability Measurements of Osseointegrated Implants Using Osstell in Partially Edentulous Jaws after 1 Year of Loading: A Pilot Study
Authors: Balleri Piero , Cozzolino Annunziata , Ghelli Luca , Momicchioli Guido , Varriale Angelo
Published: October 2006

Background: The introduction of resonance frequency analysis (RFA) as a commercially available technique has made it possible to measure implant stability in implant stability quotient (ISQ) units at any time during the course of implant treatment and loading. However, no information on normal ISQ levels can be found in the literature.

Purpose: The aim of this pilot study was to measure the stability of clinically successful implants in partially edentulous patients after 1 year of loading and to study the influence of jaw, anterior/posterior position, implant length, and marginal bone level on implant stability.

Materials and Methods: Fourteen partially edentulous patients previously treated with 45 implants were subjected to clinical and radiographie evaluations and RFA measurements using Osstell (Integration Diagnostics, Sävedalen, Sweden) after 1 year of loading.

Results: All 45 implants were stable, and implant stability levels were in the range of 57 to 82 ISQ units with a mean of 69 ± 6.5 ISQ after 1 year of loading. Mandibular implants were more stable than were maxillary ones. There were no differences between anterior and posterior implants. No correlation could be found between implant length and stability. Only minor marginal bone resorption was observed.

Conclusions: The results from this limited material showed that successfully integrated implants have ISQ levels from 57 to 82 ISQ with a mean of 69 ISQ after 1 year of loading. Mandibular implants are more stable than are maxillary ones. High implant stability can be achieved with short implants and placement in posterior regions.
rhBMP‐2/αBSM® Induces Significant Vertical Alveolar Ridge Augmentation and Dental Implant Osseointegration
Authors: Wikesjö Ulf M.E. , Sorensen Rachel G. , Kinoshita Atsuhiro , Wozney John M.
Published: October 2006

Background: Recombinant human bone morphogenetic protein 2 (rhBMP‐2) in a carrier has been shown to induce significant bone formation. Several candidate carriers, however, lack structural integrity to offset compressive forces that may compromise rhBMP‐2 bone induction, in particular, for challenging onlay indications such as alveolar ridge augmentation.

Purpose: The objective of this study was to evaluate rhBMP‐2 in a calcium‐phosphate cement carrier, αBSM, for vertical alveolar ridge augmentation and immediate dental implant Osseointegration.

Materials and Methods: Six adult Hound Labrador mongrels with 5 mm critical size supra‐alveolar peri‐implant defects were used. Three animals received rhBMP‐2/αBSM (rhBMP‐2 at 0.40 and 0.75 mg/mL) in contralateral jaw quadrants (total implant volume/defect ∼ 1.5 mL). Three animals received αBSM without rhBMP‐2 (control group). The animals were euthanized at 16 weeks post surgery, and block biopsies were processed for histologie and histometric analysis.

Results: rhBMP‐2/αBSM induced substantial augmentation of the alveolar ridge. Control sites exhibited limited new bone formation. Vertical bone augmentation averaged (SD) 4.9 ± 1.0 mm (rhBMP‐2 at 0.40 mg/mL), 5.3 ± 0.3 mm (rhBMP‐2 at 0.75 mg/mL), and 0.4 ± 0.4 mm (control); new bone area 8.5 ± 4.2 mm 2, 9.0 ± 1.9 mm 2, and 0.5 ± 0.4 mm 2; new bone density 55.1 ± 6.4%, 61.1 ± 6.0%, and 67.7 ± 9.5%; and new bone‐implant contact 26.9 ± 17.5%, 28.5 ± 1.4%, and 24.6 ± 16.1%, respectively. Residual αBSM comprised 1% of the new bone. Bone density for the contiguous resident bone ranged from 65 to 71%, and bone‐implant contact ranged from 49 to 64%.

Conclusions: Surgical implantation of rhBMP‐2/αBSM appears an effective protocol for vertical alveolar ridge augmentation procedures and immediate dental implant Osseointegration and for onlay indications of lesser complexity.
Retention Mechanisms and Prosthetic Complications of Implant‐Supported Mandibular Overdentures: Long‐Term Results
Authors: Dudic Alexander , Mericske‐Stern Regina
Published: October 2006

Background: Although many studies report high survival rates of mandibular implants supporting an overdenture, complications with prostheses and the need for prosthetic maintenance are not so well documented.

Purpose: The purpose of the present study was to analyze three categories of prosthetic complications in relation to the type of retention mechanism for overdenture connection to the implants (ie, rigid or resilient).

Materials and Methods: One hundred nineteen patients with a total of 258 implants participated in the study. They had been monitored regularly during an observation period of 5 to 15 years (mean 9.3 yr). Seventy‐five patients had a resilient retention device (ball anchors or a round clip bar); 44 patients had a rigid bar with or without distal extensions. The incidence and rate of complications were calculated for the overall‐ and for the 2‐ and 5‐year observation periods. Comparisons were made between the three categories of maintenance and the two types of retention. A Kaplan‐Meier analysis was applied for calculations of changes of the retention mechanism.

Results: The mean number of complications per overdenture during the entire observation period was 3.5; this did not differ statistically between the two retention groups. Some significant differences were found only for the 2‐ and 5‐ year period. Broken, loose, or lost female parts were more frequently observed with resilient devices, as were repairs and relining of the resin denture base, whereas tightening of bar retainers was more typical with rigid bars. A change from a resilient retention device to a rigid bar was performed more often than vice versa but not at a statistically significant level.

Conclusion: Although these long‐term results do not indicate a significant difference between the retention groups, a slight superiority of the rigid bar is suggested.
Immediate Functional Loading of Brånemark System® Implants with Enhanced Initial Stability: A Prospective 1– to 2‐Year Clinical and Radiographic Study
Authors: Calandriello Roberto , Tomatis Massimiliano , Rangert Bo
Published: October 2006

Background:

The interest in the benefits of immediate loading of titanium implants has recently involved fixed prostheses for partially edentulous areas. The advantages of this approach well justify the need for extending the procedure to all regions of the mouth. Current available clinical literature on this subject is incomplete.

Purpose:

The purpose of this study is to investigate the clinical outcome of the immediate loading of Brånemark System® implants (Nobel Biocare AB, Gothenburg, Sweden) inserted with enhanced initial stability principally in posterior sites (78%).

Materials and Methods:

The present study was conducted in 26 consecutively treated patients. A total of 50 Brånemark System machined surface implants were placed supporting 30 fixed temporary partial dentures in light occlusion. All implants were followed up for a minimum of 1 year of function. Minimum requirements for immediate loading were proposed. Bone quality and quantity were classified according to Lekholm and Zarb's criteria. Stability of the marginal bone level, both mesial and distal, was measured on the basis of radiographic analysis. Implant survival rate was calculated according to Kaplan‐Meier analysis. The peak insertion torque employed during fixture placement was between 40 and 72 Ncm, except in the case of one implant that was lost.

Results:

Overall survival rate was 98%. An unpaired t‐test revealed bone remodeling conforming to biologic width establishment (p < .005).

Conclusions:

Within the limit of this study, immediate loading appears to be a viable procedure in posterior sites and for a growing number of clinical indications. Enhanced implant stability and light occlusion seem to be security factors. In spite of unfavorable conditions such as the presence of quality 4 bone and a lack of splinting, all implants with enhanced primary stability survived.
Immediate Loading in the Maxilla Using Flapless Surgery, Implants Placed in Predetermined Positions, and Prefabricated Provisional Restorations: A Retrospective 3‐Year Clinical Study
Authors: Rocci Antonio , Martignoni Massimiliano , Gottlow Jan
Published: October 2006

Background:

Immediate loading of dental implants shortens the treatment time and makes it possible to give the patient an esthetic appearance during the whole treatment period.

Purpose:

The aim of the present study was to evaluate an immediate‐loading treatment protocol, which included flapless surgery, implants placed in predetermined positions and connected to prefabricated provisional restorations, and the 3‐year clinical results.

Materials and Methods:

A total of 97 Brånemark System® Mk IV implants (Nobel Biocare AB, Gothenburg, Sweden) with a machined surface were inserted in the maxillas of 46 patients. A presurgical three‐dimensional model of the patients' soft tissue and underlying alveolar bone anatomy was created, which allowed the clinician to place the implants in predetermined positions and connect them to prefabricated provisional restorations. A surgical template with drilling guides corresponding to each implant was used. The apical part of the master guide was equipped with a circular “mucotome,” which punched out a 5 mm hole in the mucosa to eliminate the need for flap elevation. The patients received 25 fixed partial prostheses and 27 single‐tooth restorations. Bone quality and quantity were assessed. Radiographic examinations were performed on the day of surgery/loading and at the 1‐, 2‐, and 3‐year follow‐up visits.

Results:

All implant sites showed intact buccal and lingual bone walls during surgery, confirming the accuracy of the bone‐mapping procedure. The prefabricated temporary restorations fitted, meaning that the implants were positioned clinically in the same way as on the cast. Nine implants in eight patients failed during the first 8 weeks of loading. This resulted in a cumulative survival rate of 91% after 3 years of prosthetic load. The survival rate of splinted implants was 94%. The number of failed implants was significantly higher in cases of single‐tooth replacements and placement in soft bone sites and smokers. The failed implants were successfully replaced according to a two‐stage protocol. All patients finally received the expected restoration. The marginal bone resorption was on average 1.0 mm during the first year of loading, 0.4 mm during the second year, and 0.1 mm during the third year.

Conclusions:

The study confirmed the feasibility of an immediate‐loading treatment protocol in the maxilla, which included flapless surgery, implants and abutments placed in predetermined positions, and prefabricated provisional restorations. All failures occurred within the first 2 months of loading. The unchanged survival rate and the low average bone loss found during the following 34‐month study period indicate a good long‐term prognosis for the performed immediate‐loading treatment.