bluuebunny/crossref_metadata_2025 huggingface dataset:
Proopiomelanocortin Peptides Are Not Essential for Development of Ethanol‐Induced Behavioral Sensitization
Authors: Sharpe Amanda L. , Low Malcolm J.
Published: April 2009

Background:  Behavioral sensitization is a result of neuroadaptation to repeated drug administration and is hypothesized to reflect an increased susceptibility to drug abuse. Proopiomelanocortin (POMC) derived peptides including β‐endorphin and α‐melanocyte stimulating hormone have been implicated in development of behavioral sensitization and the reinforcing effects of alcohol and other drugs of abuse. This study used a genetically engineered mouse strain that is deficient for neural POMC to directly determine if any POMC peptides are necessary for the development of ethanol‐induced locomotor sensitization.

Methods:  Adult female mice deficient for POMC in neurons only (Pomc−/−Tg/Tg, KO) and wildtype (Pomc+/+Tg/Tg, WT) littermates were injected once daily with either saline or ethanol (i.p.) for 12 to 13 days. On ethanol test day (day 13 or 14) all mice from both treatment groups received an i.p. injection of ethanol immediately before a 15‐minute analysis of locomotor activity. Blood ethanol concentration (BEC) was measured on ethanol test day immediately following the test session. Baseline locomotor activity was measured for 15 minutes after a saline injection 2 days later in both groups.

Results:  There was no significant difference in BEC between genotypes (WT = 2.11 ± 0.06; KO = 2.03 ± 0.08 mg/ml). Both WT and nPOMC‐deficient mice treated repeatedly with ethanol demonstrated a significant increase in locomotor activity on test day when compared to repeated saline‐treated counterparts. In addition, mice of both genotypes in the repeated saline groups showed a significant locomotor stimulant response to acute ethanol injection.

Conclusions:  Central POMC peptides are not required for either the acute locomotor stimulatory effect of ethanol or the development of ethanol‐induced locomotor sensitization. While these peptides may modulate other ethanol‐associated behaviors, they are not essential for development of behavioral sensitization.
Nitric Oxide‐Mediated Intestinal Injury Is Required for Alcohol‐Induced Gut Leakiness and Liver Damage
Authors: Tang Yueming , Forsyth Christopher B. , Farhadi Ashkan , Rangan Jayanthi , Jakate Shriram , Shaikh Maliha , Banan Ali , Fields Jeremy Z. , Keshavarzian Ali
Published: April 2009

Background: Alcoholic liver disease (ALD) requires endotoxemia and is commonly associated with intestinal barrier leakiness. Using monolayers of intestinal epithelial cells as an in vitro barrier model, we showed that ethanol‐induced intestinal barrier disruption is mediated by inducible nitric oxide synthase (iNOS) upregulation, nitric oxide (NO) overproduction, and oxidation/nitration of cytoskeletal proteins. We hypothesized that iNOS inhibitors [NG‐nitro‐l‐arginine methyl ester (l‐NAME),l‐N6‐(1‐iminoethyl)‐lysine (l‐NIL)] in vivo will inhibit the above cascade and liver injury in an animal model of alcoholic steatohepatitis (ASH).

Methods: Male Sprague–Dawley rats were gavaged daily with alcohol (6 g/kg/d) or dextrose for 10 weeks ± l‐NAME,l‐NIL, or vehicle. Systemic and intestinal NO levels were measured by nitrites and nitrates in urine and tissue samples, oxidative damage to the intestinal mucosa by protein carbonyl and nitrotyrosine, intestinal permeability by urinary sugar tests, and liver injury by histological inflammation scores, liver fat, and myeloperoxidase activity.

Results: Alcohol caused tissue oxidation, gut leakiness, endotoxemia, and ASH.l‐NIL andl‐NAME, but not thed‐enantiomers, attenuated all steps in the alcohol‐induced cascade including NO overproduction, oxidative tissue damage, gut leakiness, endotoxemia, hepatic inflammation, and liver injury.

Conclusions: The mechanism we reported for alcohol‐induced intestinal barrier disruption in vitro — NO overproduction, oxidative tissue damage, leaky gut, endotoxemia, and liver injury — appears to be relevant in vivo in an animal model of alcohol‐induced liver injury. That iNOS inhibitors attenuated all steps of this cascade suggests that prevention of this cascade in alcoholics will protect the liver against the injurious effects of chronic alcohol and that iNOS may be a useful target for prevention of ALD.
Do Higher Real Minimum Wages Lead to More High School Dropouts? Evidence from Maryland Across Races, 1993–2004
Authors: Crofton Stephanie O. , Anderson William L. , Rawe Emily C.
Published: April 2009

Abstract

We explore whether higher levels of the real minimum wage have differing effects on high school dropout rates across students of various races and ethnicities (whites, African Americans, Hispanics, and Asians). Using a panel of data across Maryland counties and annual observations in 1993–2004, we found higher real minimum wages to be associated with higher dropout rates for Hispanic students, but not for other races and ethnicities. We used a variety of model specifications and explanatory variables, including real income, the unemployment rate, teen pregnancy rates, and educational attainment among adults. Several of our findings are broadly consistent with commonly reported sociological observations regarding how behavioral choices may be affected by different levels across races and ethnicities of cultural integration of recent immigrants, family cohesiveness, the value placed on education, small business ownership, and hourly (vs. salaried) employment.
Home Ownership and School Outcomes of Children: Evidence from the PSID Child Development Supplement
Authors: Mohanty Lisa L. , Raut Lakshmi K.
Published: April 2009

Abstract

Using the PSID Child Development Supplement (CDS) and the corresponding PSID main data sets, we examine whether home ownership has positive effects on the academic achievement of children after correcting for selectivity bias and controlling for home environment, neighborhood quality, residential stability, and income. While we find no independent effects of home ownership, there are positive significant effects of home environment, neighborhood quality, and residential stability on the reading and math performance of children between the ages of three and twelve. The main policy implication of our study is that improvement of a child's home environment, residential stability, and the quality of the neighborhood is more important than ownership of a home to achieve better child outcomes. Subsidized home ownership can lead to better child outcomes to the extent that it places a child in a better home environment, in a more stable residence, and in a better neighborhood.
The Impact of American Politics on Perceptions of Women's Golfing Abilities
Authors: Arthur Michelle M. , Van Buren III Harry J. , Del Campo Robert G.
Published: April 2009

Abstract

We examine the relationship between political environments and perceptions of women's physical abilities. Using a sample of 496 golf courses located in the United States, we find a significant relationship between state political affiliations, ratings of senators and congressional representatives on a liberal to conservative continuum, and perceptions of gendered physical abilities. Institutional theory is presented as an explanation for the regional variation in perceptions of women's golfing abilities. Implications and results are discussed. Suggestions for further research are presented.
Migration and the Tiebout‐Tullock Hypothesis Revisited
Authors: Cebula Richard J.
Published: April 2009

Abstract

This study investigates, using state‐level data for the period 2000–2005, the Tiebout hypothesis (as extended by Tullock) of “voting with one's feet.” This analysis differs from previous related studies not only in its adoption of more current migration and other data but also in other ways. First, unlike most earlier related studies, it includes a separate measure of the overall cost of living; second, it examines per pupil (rather than per capita) outlays on public primary and secondary education; and third, in addition to property taxes, it also focuses on per capita state income tax burdens. Inclusion of the last of these variables in the analysis is based on studies that have found the existence of a state income tax to have influenced migration patterns and other studies that have found higher state income tax levels to have resulted in reduced per capita income growth over time. Moreover, including both property tax burdens and income tax burdens broadens the scope of the hypothesis. Strong empirical support for the Tiebout‐Tullock hypothesis (as interpreted here) is obtained for the study period.
An Introduction to Destructive Coordination
Authors: Vahabi Mehrdad
Published: April 2009

Abstract

Polanyi (1944, [1957]1968) has distinguished three “patterns of social integration,” namely, “reciprocity,”“redistribution,” and “exchange.” This triad has provided the starting point for most subsequent discussion. Our purpose is to introduce a further type of coordination, the “destructive mode of coordination.” This mode achieves coordination by intimidation, threat, and the use of non‐institutionalized coercive means. Resources and human efforts are allocated in order to appropriate what other people produce. Two simple examples provide an introductory illustration: traffic circles (roundabouts) and prisons. Appropriation through pirating provides a further example of destructive coordination. More specifically, biopiracy (blood patenting) is discussed in order to clarify the relationship between destructive coordination and the institutionalization of property rights. Finally, we focus on the role of destructive coordination as a transitional mechanism that is supported by the institutional vacuum, ultimately yielding to other modes of coordination.
How Bad Can a Crisis Be If It Does Not Top the News?
Authors: Mazur Allan
Published: April 2009

Sudden onset of front‐page news about the U.S. financial crisis, beginning September 6, 2008, may have exacerbated underlying financial problems and facilitated the spread of risk panic to other nations.
Entrepreneurial Orientation and Business Performance: An Assessment of past Research and Suggestions for the Future
Authors: Rauch Andreas , Wiklund Johan , Lumpkin G.T. , Frese Michael
Published: April 2009

Entrepreneurial orientation (EO) has received substantial conceptual and empirical attention, representing one of the few areas in entrepreneurship research where a cumulative body of knowledge is developing. The time is therefore ripe to document, to review, and to evaluate the cumulative knowledge on the relationship between EO and business performance. Extending beyond qualitative assessment, we undertook a meta–analysis exploring the magnitude of the EO–performance relationship and assessed potential moderators affecting this relationship. Analyses of 53 samples from 51 studies with an N of 14,259 companies indicated that the correlation of EO with performance is moderately large (r = .242) and that this relationship is robust to different operationalizations of key constructs as well as cultural contexts. Internal and environmental moderators were identified, and results suggest that additional moderators should be assessed. Recommendations for future research are developed.
Founders, Private Equity Investors, and Underpricing in Entrepreneurial IPOs
Authors: Bruton Garry D. , Chahine Salim , Filatotchev Igor
Published: April 2009

One of the most important events in the life of an entrepreneurial firm is when it undergoes an initial public offering (IPO). Combining signaling theory with research on the role of information asymmetry in pricing of IPOs this study examines the performance outcomes of two distinct types of agency conflicts at the time of the IPO: adverse selection and moral hazard. Empirical results show a curvilinear (U–shaped) relationship between founders‘ retained equity and underpricing. This suggests that founders‘ retained ownership in an entrepreneurial IPO limits adverse selection problems and the associated IPO underpricing; however, at some point entrepreneurs‘ investment and risk become so great that entrepreneurs may no longer act rationally and moral hazard increases. Empirical findings also indicate that the retained ownership of business angels has a stronger mitigating effect on adverse selection and moral hazard problems than do venture capitalist investors.
Ferroelectric Phase Stability Studies in Spray Deposited KNO3:PVA Composite Films
Authors: Dabra Navneet , Hundal Jasbir S. , Sekhar Kopple C. , Nautiyal Arvind , Nath Rabinder
Published: April 2009

The composite films of potassium nitrate (KNO3):poly(vinyl alcohol) (PVA) have been prepared at different temperatures by spray‐deposition technique. Ferroelectric hysteresis loops were traced at room temperature for the composite films using modified Sawyer and Tower circuit. The X‐ray diffraction studies confirm the existence of ferroelectric phase III of KNO3 in the composite films at the room temperature, where this phase in pure KNO3 films is known to exist in the temperature range 110°–124°C. The composite films deposited at 200°C shows the optimum remanent polarization, Pr∼17 μC/cm2. The Pr was studied in the frequency range 10 Hz–1 kHz. The stability of the Pr in the composite films exhibits improved fatigue compared with that of quenched KNO3 films. The capacitance–voltage (C–V) characteristics exhibits butterfly features which supports the presence of ferroelectric phase in the composite films. The atomic force microscopy images show that the composite films have uniform dispersion of KNO3 particles in the PVA matrix.
The Role of Parental Attitudes and Monitoring in the Risk Exposure of Young Children1
Authors: Waylen Andrea , McKenna Frank
Published: April 2009

The parental monitoring literature debates the role of parental activity, as opposed to parental knowledge in childhood risk taking. We examined parents’ attitudes and behaviors regarding roadside supervision of children aged 4 to 6 years using self‐report and observational measures. Although parents perceived sons as less careful than daughters, they reported no sex differences in the age children would be allowed out unsupervised. There were no self‐report differences in supervision according to socioeconomic status. However, roadside observations showed that boys and children from a lower socioeconomic area received less supervision than girls or those from a higher socioeconomic area. Such findings contribute to our understanding of the sex and socioeconomic differences in accident involvement and the role of parental monitoring.
Organizational Culture and Similarity Among Team Members’ Salience of Multiple Diversity Characteristics
Authors: Randel Amy E. , Earley P. Christopher
Published: April 2009

Research often has focused on the presence of individuals’ demographic differences, rather than the perception of such differences. We examined how organizational culture relates to similarity among individuals’ salience of their team members’ diversity characteristics. Moreover, we introduced a new approach to studying multiple diversity characteristics simultaneously. Team members who perceive their organizational culture as emphasizing respect for people were found to be unlikely to hold convergent views of their team members’ demographics. Also, high‐performing team members were found to view the salience of demographic characteristics similarly to other team members. Our findings suggest that an organizational culture emphasizing respect for people may be associated with unexpected barriers among team members that pose a threat to effective team functioning.
Resistance to Deficient Organizational Authority: The Impact of Culture and Connectedness in the Workplace
Authors: Wosinska Wilhelmina , Cialdini Robert B. , Petrova Petia K. , Barrett Daniel W. , Gornik‐Durose Malgorzata , Butner Jonathan , Griskevicius Vladas
Published: April 2009

In 2 countries differing on individualistic–collectivistic orientation, we investigated resistance to a request made by a manager perceived as lacking personal power based on a key attribute (e.g., expertise, relationality). Results of an experiment with Polish and American participants were consistent with cultural differences in the preferred attribute of leaders in the 2 nations. Participants were more resistant to a manager who lacked the attribute more valued in their culture: Americans were more resistant to managers perceived as lacking in expertise, whereas Poles were more resistant to managers perceived as lacking in relational skills. This effect occurred only under conditions of well‐established workplace relationships, suggesting that group connectedness creates a tendency to behave in line with predominant cultural norms.
Is Transformational Leadership Always Perceived as Effective? Male Subordinates' Devaluation of Female Transformational Leaders1
Authors: Ayman Roya , Korabik Karen , Morris Scott
Published: April 2009

This study investigated the impact of the gender composition of the leader–subordinate dyad on the relationship between leaders' transformational leadership behavior and their subordinates' ratings of the leaders' effectiveness. There were 109 dyads of leaders (58 male, 51 female) paired with a subordinate who was either the same or a different gender from themselves. The relationship between a leader's self‐report on transformational leadership and their subordinates' evaluation of their performance was significantly less positive for female leaders with male subordinates than for female leaders with female subordinates. The male and female subordinates of male leaders rated their performance as equally effective, regardless of their levels of transformational leadership.
Preference for Same‐ Versus Cross‐Sex Friendships1
Authors: Baumgarte Roger , Nelson Donna Webster
Published: April 2009

How is preferring same‐ vs. cross‐sex friendships related to one's perceptions of these friendships? In Phase 1, college students (N = 122) listed qualities they valued in their same‐ and cross‐sex friends. In Phase 2, survey items constructed from the responses were administered to 231 students who indicated a preference for same‐ vs. cross‐sex friendship. Those who reported a preference for opposite‐sex friends rated these friendships as higher in closeness, trust, caring, having common interests, and providing narcissistic benefits, compared to those who reported a preference for same‐sex friends. Results demonstrate that gender differences often associated with close friendships are greatly attenuated and sometimes reversed when preference for same‐ vs. cross‐sex friendship is included as a moderating variable.
The Devaluation of Relationships (not Individuals): The Case of Dyadic Relationship Stigmatization
Authors: Conley Terri D. , Rabinowitz Joshua L.
Published: April 2009

This study addresses how people devalue romantic relationships without devaluing the individuals in the relationship. We examined perceptions of condom use in close relationships in 3 studies. Relationships of couples who used condoms were devalued, relative to relationships of those who used oral contraceptives. However, the perceptions of individuals in the relationships were unchanged by type of birth‐control use. In 2 studies, the dyadic devaluation concept was extended to relationships in which one partner was significantly older than the other. Participants believed that relationships in which the woman was substantially older than the man were of lesser quality than relationships in which the man and woman were the same age. Implications for stigma and person perception research are discussed.
Juries, Gender, and Assault Weapons1
Authors: Meyer Glenn E. , Baños Alicia S. , Gerondale Tiffany , Kiriazes Christine , Lakin Claire M. , Rinker Amanda C.
Published: April 2009

Firearms appearance can have psychological import in legal proceedings by keying aggressive ideations, impacting sentencing and gender‐based attributions. We presented mock jurors with a homeowner's defensive gun use. Reasonable arguments were for shooting or not in the scenario by the defendant. The firearm varied in type. Assault rifle use led to harsher legal outcomes than did other firearms. A female defendant was at more risk than a male. In the last experiment, a police shooting scenario was tested. In that case, the male officer was at more risk than the female officer when wielding the assault rifle. Weapons and gender interactions were, for the most part, congruent with social cognitive theories of attribution and weapons priming of aggressive ideation.
Real‐Time Realities: The Application of Commercial Information Technology to Combat Control Systems
Authors: ZILIC ANTHONY M. , BARON NEIL T.
Published: April 2009

The Navy is steward to the most lethal arsenal of national and combat power ever amassed. The command responsibilities associated with such destructive force require us to always be in complete positive control over these weapons. The Navy, to meet this mission requirement, traditionally developed its systems using special purpose technology to achieve “Deterministic Control.” Control system technologies are fielded in all aspects of shipboard combat systems with specific challenges in timing and safety in the surface anti‐air warfare systems, the submarine launched ballistic missile systems, and air launched missile systems. Today's naval combat system is a highly complex, computer‐based control system that is evolving within the framework of the commercial computer industry. This paper will briefly describe some critical and unique characteristics of a large‐scale digital weapon control system and identify emerging technologies that have the potential to respond to the Navy's warfighting needs.
Structuring a Flexible, Affordable Naval Force to Meet Strategic Demand in the 21st Century
Authors: MORELAND JAMES D.
Published: April 2009

“While defending our homeland and defeating adversaries in war remain the indisputable ends of seapower, it must be applied more broadly if it is to serve the national interest.” This concept from A Cooperative Strategy for 21st Century Seapower (Conway et al. 2007), stresses the importance of protecting the interests of the United States while promoting security, stability, and trust. This paper explains the challenges faced by the naval enterprise, methods for improving our force planning and acquisition processes, and the need for naval capabilities to be transformed through the co‐evolution of technology and organizational cultures. A force structure framework that provides a flexible, adaptive, and affordable force without regard to the future state of the world is a critical requirement in the “Next Navy” and the “Navy after Next.” The agility, scalability, and flexibility of an adaptive force provide commanders a range of options when responding to a crisis situation. This paper will identify characteristics and capabilities required to address the range of threats that exist today as well as threats expected in future environments.
Enabling CAIV through Design, Modularity, and Program Management
Authors: DOERRY NORBERT
Published: April 2009

Many naval ship acquisition programs have not been able to effectively implement cost as an independent variable (CAIV). With a CAIV approach, operational requirements provided by the customer are given in terms of threshold and objective values. The range between these two values provides the program manager with trade‐space to match the available funds with the capabilities that can be bought for that amount—the total program cost remains a constant. In practice though, much of the final cost of an acquisition program is fixed early in the design process through basic design decisions on architecture and the allocation of operational requirements and derived requirements to systems. Unfortunately, while much of the cost is determined early in the design process, estimating that cost to any degree of certainty is nearly impossible. As the costs of the program are better understood, the remaining design flexibility to adjust to increasing costs may not be sufficient to enable the program manager time to take corrective action when the cost estimates indicate a possible problem. This paper describes the techniques, including the use of modularity, cost contingencies, and set‐based design, to provide the program manager with sufficient flexibility to implement CAIV. The views expressed in this paper are those of the author and are not necessarily official policy of the US Navy or any other organization. The intent of this paper is to foster dialogue to gain a better understanding of how to develop an acquisition strategy and systems engineering strategy to enable CAIV.
Medicago truncatula‐derived calcium oxalate crystals have a negative impact on chewing insect performance via their physical properties
Authors: Park Sang‐Hyuck , Doege Sarah J. , Nakata Paul A. , Korth Kenneth L.
Published: April 2009

Plant structural traits often act as defenses against herbivorous insects, causing them to avoid feeding on a given plant or tissue. Mineral crystals of calcium oxalate in Medicago truncatula Gaertn. (Fabaceae) leaves have previously been shown to be effective deterrents of lepidopteran insect feeding. They are also inhibitors of conversion of plant material into insect body mass during or after consumption. Growth of beet armyworm, Spodoptera exigua Hübner (Lepidoptera: Noctuidae), larvae was correspondingly greater on calcium oxalate‐defective (cod) mutants of M. truncatula with lower levels of crystal accumulation. Data presented here show that insects feeding on M. truncatula leaves with calcium oxalate crystals experience greater negative effects on growth and mandible wear than those feeding on artificial diet amended with smaller amorphous crystals from commercial preparations. Commercial calcium oxalate can be added to insect artificial diet at levels up to 7.5‐fold higher than levels found in wild‐type M. truncatula leaves with minimal effect on insect growth or lepidopteran mandibles. These data suggest that negative impacts of calcium oxalate in the diet of larvae are due to physical factors, and not toxicity of the compound, as high levels of the commercial crystals are readily tolerated. In contrast to the dramatic physical effects that M. truncatula‐derived crystals have on insect mandibles, we could detect no damage to insect peritrophic gut membranes due to consumption of these crystals. Taken together, the data indicate that the size and shape of prismatic M. truncatula oxalate crystals are important factors in determining effects on insect growth. If manipulation of calcium oxalate is to be used in developing improved insect resistance in plants, then our findings suggest that controlling not only the overall amount, but also the size and shape of crystals, could be valuable traits in selecting desirable plant lines.
Context‐dependent transmission of a generalist plant pathogen: host species and pathogen strain mediate insect vector competence
Authors: Lopes João R. S. , Daugherty Matthew P. , Almeida Rodrigo P. P.
Published: April 2009

The specificity of pathogen–vector–host interactions is an important element of disease epidemiology. For generalist pathogens, different pathogen strains, vector species, or host species may all contribute to variability in disease incidence. One such pathogen is Xylella fastidiosa Wells et al., a xylem‐limited bacterium that infects dozens of crop, ornamental, and native plants in the USA. This pathogen also has a diverse vector complex and multiple biologically distinct strains. We studied the implications of diversity in this pathogen–vector–host system, by quantifying variability in transmission efficiency of different X. fastidiosa strains (isolates from almond and grape genetic groups) for different host plants (grape, almond, and alfalfa) by two of the most important vectors in California: glassy‐winged sharpshooter [Homalodisca vitripennis (Germar)] and green sharpshooter (Draeculacephala minerva Ball) (both Hemiptera: Cicadellidae). Transmission of isolates of the almond strain by H. vitripennis did not differ significantly, whereas transmission varied significantly among isolates from the grape strain (15–90%). Host plant species did not affect H. vitripennis transmission. Conversely, D. minerva efficiency was mediated by both host plant species and pathogen strain. No acquisition of an almond isolate occurred regardless of plant type (0/122), whereas acquisition of a grape isolate from alfalfa was 10‐fold higher than from grape or almond plants. These results suggest that pathogen, vector, and host diversity impose contingencies on the transmission ecology of this complex disease system. Studies aimed at the development of management strategies for X. fastidiosa diseases should consider the complexity of these interactions as they relate to disease spread.
Calcium pantothenate modulates gene expression in proliferating human dermal fibroblasts
Authors: Wiederholt Tonio , Heise Ruth , Skazik Claudia , Marquardt Yvonne , Joussen Sylvia , Erdmann Kati , Schröder Henning , Merk Hans F. , Baron Jens Malte
Published: April 2009

Abstract:  Topical application of pantothenate is widely used in clinical practice for wound healing. Previous studies identified a positive effect of pantothenate on migration and proliferation of cultured fibroblasts. However, these studies were mainly descriptive with no molecular data supporting a possible model of its action. In this study, we first established conditions for an in vitro model of pantothenate wound healing and then analysed the molecular effects of pantothenate. To test the functional effect of pantothenate on dermal fibroblasts, cells were cultured and in vitro proliferation tests were performed using a standardized scratch test procedure. For all three donors analysed, a strong stimulatory effect of pantothenate at a concentration of 20 μg/ml on the proliferation of cultivated dermal fibroblasts was observed. To study the molecular mechanisms resulting in the proliferative effect of pantothenate, gene expression was analysed in dermal fibroblasts cultivated with 20 μg/ml of pantothenate compared with untreated cells using the GeneChip® Human Exon 1.0 ST Array. A number of significantly regulated genes were identified including genes coding for interleukin (IL)‐6, IL‐8, Id1, HMOX‐1, HspB7, CYP1B1 and MARCH‐II. Regulation of these genes was subsequently verified by quantitative real‐time polymerase chain reaction analysis. Induction of HMOX‐1 expression by pantothenol and pantothenic acid in dermal cells was confirmed on the protein level using immunoblots. Functional studies revealed the enhanced suppression of free radical formation in skin fibroblasts cultured with panthenol. In conclusion, these studies provided new insight in the molecular mechanisms linked to the stimulatory effect of pantothenate and panthenol on the proliferation of dermal fibroblasts.
Melatonin protects kidney grafts from ischemia/reperfusion injury through inhibition of NF‐kB and apoptosis after experimental kidney transplantation
Authors: Li Zhanqing , Nickkholgh Arash , Yi Xue , Bruns Helge , Gross Marie‐Luise , Hoffmann Katrin , Mohr Elvira , Zorn Markus , Büchler Markus W. , Schemmer Peter
Published: April 2009

Abstract:  Free radicals are involved in pathophysiology of ischemia/reperfusion injury (IRI). Melatonin is a potent scavenger of reactive oxygen and nitrogen species. Thus, this study was designed to elucidate its effects in a model of rat kidney transplantation. Twenty Lewis rats were randomly divided into 2 groups (n = 10 animals each). Melatonin (50 mg/kg BW) dissolved in 5 mL milk was given to one group via gavage 2 hr before left donor nephrectomy. Controls were given the same volume of milk only. Kidney grafts were then transplanted into bilaterally nephrectomized syngeneic recipients after 24 hr of cold storage in Histidine–Tryptophan–Ketoglutarate solution. Both graft function and injury were assessed after transplantation through serum levels of blood urea nitrogen (BUN), creatinine, transaminases, and lactate dehydrogenase (LDH). Biopsies were taken to evaluate tubular damage, the enzymatic activity of superoxide dismutase (SOD) and lipid hydroperoxide (LPO), and the expression of NF‐kBp65, inducible nitric oxide synthase (iNOS), caspase‐3 as indices of oxidative stress, necrosis, and apoptosis, respectively. Melatonin improved survival (P < 0.01) while decreasing BUN, creatinine, transaminases, and LDH values up to 39–71% (P < 0.05). Melatonin significantly reduced the histological index for tubular damage, induced tissue enzymatic activity of SOD while reducing LPO. At the same time, melatonin down‐regulated the expression of NF‐kBp65, iNOS, and caspase‐3. In conclusion, donor preconditioning with melatonin protected kidney donor grafts from IRI‐induced renal dysfunction and tubular injury most likely through its anti‐oxidative, anti‐apoptotic and NF‐kB inhibitory capacity.
Melatonin induces mitochondrial‐mediated apoptosis in human myeloid HL‐60 cells
Authors: Bejarano Ignacio , Redondo Pedro C. , Espino Javier , Rosado Juan A. , Paredes Sergio D. , Barriga Carmen , Reiter Russel J. , Pariente José A. , Rodríguez Ana B.
Published: April 2009

Abstract:  The role of melatonin in the mediation of apoptotic events has recently gained attention, especially after recent studies have reported that melatonin exerts antiapoptotic actions in normal cells but may activate proapoptotic pathways in some tumor cells. Here, we have evaluated the effect of melatonin on apoptosis in the human leukemia cell line HL‐60. Melatonin treatment (1 mm) induced a significant increase in caspase‐3 and ‐9 activities. The effect of melatonin on the activation of caspases was time dependent, reaching a maximum after 12 hr of stimulation, and then decreasing to a minimum after 72 hr. Treatment with melatonin also evoked mitochondrial membrane depolarization and permeability transition pore induction, which caused loss of mitochondrial staining by calcein, and increased cell death by apoptosis/necrosis as demonstrated by propidium iodide positive‐staining of cells after 72 hr of stimulation. In addition, the exposure of cells to melatonin resulted in an activation and association of the proapoptotic proteins Bax and Bid, as well as promoting detectable increases in the expression of both proteins. We conclude that melatonin has proapoptotic and/or oncostatic effects in the human myeloid cell line HL‐60.
Altered basal and postprandial plasma melatonin, gastrin, ghrelin, leptin and insulin in patients with liver cirrhosis and portal hypertension without and with oral administration of melatonin or tryptophan
Authors: Celinski K. , Konturek P.C. , Slomka M. , Cichoz‐Lach H. , Gonciarz M. , Bielanski W. , Reiter R.J. , Konturek S.J.
Published: April 2009

Abstract:  This investigation was designed to assess the effects of oral administration of melatonin (10 mg) and tryptophan (Trp) (500 mg) on fasting and postprandial plasma levels of melatonin, gastrin, ghrelin, leptin and insulin in 10 healthy controls and in age‐matched patients with liver cirrhosis (LC) and portal hypertension. Fasting plasma melatonin levels in LC patients were about five times higher (102 ± 15 pg/mL) than in healthy controls (22 ± 3 pg/mL). These levels significantly increased postprandially in LC patients, but significantly less so in controls. Treatment with melatonin or l‐Trp resulted in a further significant rise in plasma melatonin, both under fasting and postprandial conditions, particularly in LC patients. Moreover, plasma gastrin, ghrelin, leptin and insulin levels under fasting and postprandial conditions were significantly higher in LC subjects than in healthy controls and they further rose significantly after oral application of melatonin or Trp. This study shows that: (a) patients with LC and portal hypertension exhibit significantly higher fasting and postprandial plasma melatonin levels than healthy subjects; (b) plasma ghrelin, both in LC and healthy controls reach the highest values under fasting conditions, but decline postprandially, especially after oral application of melatonin or Trp; and (c) plasma melatonin, gastrin, ghrelin and insulin levels are altered significantly in LC patients with portal hypertension compared with that in healthy controls possibly due to their portal systemic shunting and decreased liver degradation.
A study of a method for distribution analysis of skin color
Authors: Ha Seunghan , Lee Minhee , Lee Onseok , Lee Gunwoo , Kim Jeayoung , Moon Jongsub , Kim Mingi , Oh Chilhwan
Published: April 2009

Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color.

Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information.

In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method.

Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L*, b*, a*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L* parameter and a significant statistical difference in the x and z parameters, except b*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L* parameter and a significant statistical difference in the parameters except y and b*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters.

Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too.
A pilot study of the association between cariogenic oral bacteria and preterm birth*
Authors: Durand R , Gunselman EL , Hodges JS , DiAngelis AJ , Michalowicz BS
Published: April 2009

Objectives:  We examined the associations between preterm birth and low birth weight and maternal caries history, maternal periodontal status, and salivary levels of mutans streptococci and Lactobacilli.

Design:  This study was a matched case–control study in women during their pregnancy or up to 8 weeks after delivery.

Subjects and methods:  Thirty‐four women delivering before 37 weeks gestation were recruited along with 73 term controls matched for age and race/ethnicity. Demographic and obstetric information was collected from questionnaires and medical records and oral examinations along with commercial salivary tests were completed within the study groups.

Main outcome measures:  The main outcome variables were the preterm birth and low birth weight status. The independent variables measured were the salivary levels of Lactobacilli and mutans streptococci and the caries and periodontal status of the subjects.

Results:  The odds ratio comparing low levels of bacteria in preterm mothers and controls was statistically significant for Lactobacilli (odds ratio (OR) = 3.45, 95% confidence interval (CI)  = 1.27 to 10.00) and almost significant for mutans streptococci (OR = 2.63, 95% CI = 0.95 to 8.33). Clinical caries and periodontal disease measures did not differ significantly between groups.

Conclusion:  Within the limitation of our study, low levels of Lactobacilli in saliva were found to be associated with preterm birth.
Child abuse and dental neglect: the dental team’s role in identification and prevention
Authors: Nuzzolese E , Lepore MM , Montagna F , Marcario V , De Rosa S , Solarino B , Di Vella G
Published: April 2009

Abstract:  Health, education and social services are placing increasing emphasis on preventing abuse and neglect by early intervention to support families where children and young people may be at risk. Dental hygienist and dental assistants, like all other health professionals, can have a part in recognizing and preventing children from those who would cause them harm. They should be aware of the warning signs, recognizing what to consider as abuse or dental neglect and know how to deal with these young patients, and to fulfil their legal and ethical obligation to report suspected cases.

The purpose of this report is to review the oral and dental aspects of child abuse and dental neglect thus helping the dental team in detecting such conditions. In particular, this report addresses the evaluation of bite marks as well as perioral and intraoral injuries, infections, early childhood caries and diseases that may be indicative of child abuse or neglect.

Emphasis is placed on an appropriate protocol to follow in the dental practice to best treat and protect children who may have suffered abuse, helping the team in the diagnosis and documentation.
Gingival recession: epidemiology and risk indicators in a university dental hospital in Turkey
Authors: Toker H , Ozdemir H
Published: April 2009

Abstract:  Objective:  Gingival recession is a common manifestation of periodontal disease, but is also associated with several risk factors. In this study, we investigated prevalence of gingival recession and assessed various risk indicators in a university dental hospital in Turkey.

Materials and methods:  The study group consisted of 831 persons (537 females, 294 males). Gingival recession, dental plaque, calculus, tobacco consumption, toothbrushing frequency, traumatic toothbrushing and high frenum were assessed. Gingival recession scored as present whenever the free gingival margin was apical to the cemento‐enamel junction and root surface was exposed.

Results:  Overall, the prevalence of gingival recession was 78.2%. The gingival recession for buccal surfaces measured approximately between 1 and 2 mm was 17.4%. The number of gingival recession site of male subjects was significantly higher than that of the female ones (P < 0.05). The dental calculus and plaque levels of mandibular teeth were significantly higher than those of the maxillary teeth (P < 0.05). The multiple regression analyses showed that age, smoking duration, traumatic toothbrushing and high frenum are significant contributors to gingival recession.

Conclusions:  Periodontal condition is very high in this population. High level of gingival recession in this population is significantly associated with a high level of dental plaque and calculus, male gender, smoking duration, toothbrushing frequency, traumatic toothbrushing and high frenum.
Growth factors in periodontal regeneration
Authors: Raja S , Byakod G , Pudakalkatti P
Published: April 2009

Abstract:  Inflammatory periodontal disease is an almost ubiquitous disorder in the adult population. Cases or sites with moderate to advanced disease often continue to show signs of inflammation after non‐surgical approach. Our current understanding of periodontal healing is based on a hypothesis by Melcher who proposed that the cell type that repopulates the exposed root surface at the periodontal repair site will define the nature of the attachment/repair that take place. If mesenchymal cells from periodontal ligament/perivascular region of the bone proliferate and colonize the root surface, regeneration occurs. Growth factors are natural cell products that are released or activated when cell division is needed. This action typically occurs during such events as wound healing or tissue regeneration. Activated platelets at the wound margins release several growth factors such as platelet‐derived growth factor (PDGF), transforming growth factor (TGF)‐α, epidermal growth factor etc. Cells adjacent to the injured site also are induced to release growth factors such as insulin‐like growth factor‐I, PDGF, TGF‐α and TGF‐α within a few hours after injury. In periodontal regeneration, the coronal re‐establishment of the periodontal ligament (PDL) is required together with corresponding cementum and supporting alveolar bone. Thus, agents which promote periodontal ligament fibroblast (PLF) proliferation and migration as well as collagen biosynthesis would appear to be mediators for enhancing new PDL formation. When combinations or cocktails of different factors are used, greater repair is achieved than when individual factors are applied.
Reproductive variability inPinus sylvestrisin southern France: Implications for invasion
Authors: Debain S. , Curt T. , Lepart J. , Prevosto B.
Published: April 2009

Abstract.Though fecundity and dispersal have been recognized as major factors in most invasion models, their ecological determinants are still poorly known. This paper aims to identify the main sources of variation in seed production and dispersal distance in a naturally expandingPinus sylvestrispopulation. We propose some tree measurements that may be related to their contribution to population expansion. We quantified cone and seed production and measured three seed characteristics related to their dispersal ability: mass, wing area and wing‐loading (mass:area ratio) in cones sampled at different relative heights and aspects in the canopy and in trees of different age and competitive status. Results showed that isolated trees had a much more abundant cone production, which was more evenly distributed in the canopy than trees within stands. Age was also positively related to cone production. Seed dimensions varied between and within trees but we found no effect of isolation or age. The strong positive correlation between wing area and seed mass leads to a limited variability of seed wing loading. Seed characteristics may thus play a minor role in individual dispersal ability and relative tree position in the stand that is strongly linked to tree fecundity should be more appropriate for estimating the individual contribution to the whole population expansion. Our results also highlight the importance of obtaining demographic data in low‐density populations to estimate the invasive potential of a species.