bluuebunny/crossref_metadata_2025 huggingface dataset:
Aloe vera in the treatment for oral submucous fibrosis – a preliminary study
Authors: Sudarshan Ramachandran , Annigeri Rajeshwari G. , Sree Vijayabala G.
Published: May 2012

J Oral Pathol Med (2012) 41: 755–761

Background and objectives:  Oral submucous fibrosis (OSMF) is a potentially malignant disorder of the oral mucosa, mainly associated with the practice of chewing gutka and betel quid. The pathogenesis is obscure, and till date, no definitive therapy is available for the management of OSMF. Hence, this preliminary study was carried out to compare the efficacy of Aloe vera with antioxidants in the treatment for OSMF.

Methods:  Twenty study subjects with OSMF were included in the study. Patients were divided into two groups. There were 10 patients in each group; group A subjects received 5 mg of aloe vera gel to be applied topically three times daily for 3 months and group B subjects received antioxidant capsules twice daily for 3 months. The results were analyzed with paired ‘t’ test and unpaired ‘t’ test.

Results:  Aloe vera responded better in all the parameters assessed and responded in all the clinicohistopathological stages particularly in those with mild‐stage clinically and early‐stage histopathologically. Aloe vera showed a statistically significant reduction in burning sensation (P = 0.008), improvement in mouth opening (P = 0.02), and cheek flexibility (P = 0.01) on comparing with the antioxidant group.

Interpretation and conclusion:  Overall assessment of the parameters depicted that Aloe vera group showed a better treatment response compared to the antioxidants group. It reduces the burning sensation and improves mouth opening thereby enhanced the patients’ compliance. It proves to be a relatively safe, can be applied topically, easily available, economical, noninvasive, and efficacious in the treatment for OSMF.
Sustained release of melatonin from poly (lactic‐co‐glycolic acid) (PLGA) microspheres to induce osteogenesis of human mesenchymal stem cells in vitro
Authors: Zhang Liangming , Zhang Jinling , Ling You , Chen Changhua , Liang Anjing , Peng Yan , Chang Hong , Su Peiqiang , Huang Dongsheng
Published: May 2012

Abstract:  Melatonin promotes bone formation and prevents bone degradation via receptor‐dependent or receptor‐independent actions. The aim of this study is to encapsulate melatonin into poly (lactic‐co‐glycolic acid) (PLGA) microspheres (PLGA‐MEL‐MS) and create a melatonin sustained release system, then to evaluate its effect on the osteogenesis of human mesenchymal stem cells (hMSCs) in vitro. PLGA‐MEL‐MS were prepared by single emulsion solvent evaporation technique. Scanning electron microscopy demonstrated the incorporation of melatonin did not disturb the conventional generation of PLGA microspheres in size and morphology. In vitro drug release assay showed that PLGA‐MEL‐MS exhibited a biphasic drug release pattern: a low initial burst release effect with approximately 40% drug release at the first 3 days and a relatively retarded and continuous release with about 85% drug release over the 25 days. Cell proliferation assay demonstrated that PLGA‐MEL‐MS had no apparent effect on proliferation of human MSCs. In an osteogenesis assay, PLGA‐MEL‐MS obviously enhanced alkaline phosphatase (ALP) mRNA expression and increased ALP activity compared to that in the control group. Meanwhile, several markers of osteoblast differentiation were also significantly upregulated, including runx2, osteopontin, and osteocalcin. Furthermore, quantificational alizarin red‐based assay demonstrated that PLGA‐MEL‐MS significantly enhanced calcium deposit of hMSCs compared to the controls. Therefore, this simple melatonin sustained release system can control released melatonin to generate a microenvironment with a relatively stable concentration of melatonin for a period of time to support osteogenic differentiation of hMSCs in vitro. This suggests that this system may be used as bone growth stimulator in bone healing in vivo.
Analysis of the expression of heat‐shock protein 27 in patients with oral lichen planus
Authors: García‐García V , Bascones‐Martínez A , García‐Kass AI , Martinelli‐Kläy CP , Küffer R , Álvarez‐Fernández E , Lombardi T
Published: May 2012

Oral Diseases (2012) 19, 65–72

Objective:  Heat‐shock protein 27 (hsp27) has been implicated in several biological events. In this experimental study, we aimed at analysing, for the first time, the expression of hsp27 in the diverse stages of oral lichen planus (OLP) lesions.

Materials and methods:  Thirty‐six biopsy specimens of patients with OLP and 10 of healthy patients were selected. OLP specimens were divided into three groups: G1 – moderate or mildly active OLP; G2 – active or moderately active atrophic OLP; G3 – mild or inactive atrophic OLP. Hsp27 expression was analysed by immunohistochemistry (staining intensity and percentage of stained cells), and results of staining were compared between the different groups. Gender, age and anatomical location were also studied.

Results:  In the basal layer, an increase of hsp27 expression in both G2 and G3 was observed when compared to G1 and control group. In contrast, a decrease of hsp27 expression in the superficial layer was observed in all groups when compared to control group.

Conclusion:  The increased expression of Hsp27 in the basal layer observed during the OLP evolution and the less staining in the superficial layers in all cases of OLP suggest that hsp27 may have a role in the OLP pathogenesis.
A discussion on the assumption of ambipolar diffusion of meteor trails in the Earth's upper atmosphere
Authors: Kumar Karanam Kishore , Subrahmanyam Kandula Venkata
Published: May 2012

For the first time, height profiles of meteor trail decay time due to the ambipolar diffusion process are estimated using temperature and pressure measurements by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on-board Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite. The comparison of the meteor trail decay time measured by a meteor radar over Thumba (8°.5 N, 77°E) and SABER offered very valuable insights into the meteor trail decay processes and also provided much needed validation for assumption of ambipolar diffusion of meteor trails. It is observed that the assumption of ambipolar diffusion is valid in the height region of 90–96 km only where both SABER and radar measurements show excellent agreement in meteor trail decay time. The present analysis also shows that there are other processes which govern the meteor trail decay in the 80–90 km region, where large deviations are found between radar and SABER measurements. The differences between the SABER- and radar-observed decay times are quantified, and the processes responsible for the observed differences are also discussed extensively in the light of present understanding. The important outcome of the present study is the validation of assumption on ambipolar diffusivity of the meteor trails, which has significant implications in estimating the temperature using meteor trail decay time.
The Relationship Between Rural Status, Individual Characteristics, and Self‐Rated Health in the Behavioral Risk Factor Surveillance System
Authors: Bethea Traci N. , Lopez Russell P. , Cozier Yvette C. , White Laura F. , McClean Michael D.
Published: May 2012

Purpose: To examine rural status and social factors as predictors of self‐rated health in community‐dwelling adults in the United States.

Methods: This study uses multinomial logistic and cumulative logistic models to evaluate the associations of interest in the 2006 US Behavioral Risk Factor Surveillance System, a cross‐sectional survey of 347,709 noninstitutionalized adults.

Findings: Self‐rated health was poorer among rural residents, compared to urban residents (OR = 1.77, 95% CI: 1.54, 1.90). However, underlying risk factors such as obesity, low income, and low educational attainment were found to vary by rural status and account for the observed increased risk (OR = 1.03, 95% CI: 0.94, 1.12). There was little evidence of effect modification by rural status, though the association between obesity and self‐rated health was stronger among urban residents (OR = 2.50, 95% CI: 2.38, 2.64) than among rural residents (OR = 2.18, 95% CI: 2.03, 2.34).

Conclusions: Our findings suggest that differences in self‐rated health by rural status were attributable to differential distributions of participant characteristics and not due to differential effects of those characteristics.
Ongoing Self‐Engagement in Quit Attempts and Cessation Outcomes Among Rural Smokers Who Were Unable to Quit After 2 Years of Repeated Interventions
Authors: Azor Hui Siu‐kuen , Nazir Niaman , Faseru Babalola , Ellerbeck Edward F.
Published: May 2012

Purpose: As many smokers experience repeated failures with cessation attempts, it has been postulated that we may create a cadre of highly resistant smokers who are unlikely to engage in treatment or succeed in quitting. Our purpose was to follow a group of recalcitrant rural smokers and examine their ongoing engagement in smoking cessation activities.

Methods: At the end of a 24‐month disease management program for rural smokers, we identified participants who reported ongoing daily smoking despite exposure to 4 previous cycles of smoking cessation interventions. At month 36 (1 year after conclusion of the study), we contacted these participants and assessed changes in smoking status and ongoing engagement in cessation activities over the preceding 6 months. We assessed quit attempts and use of pharmacotherapy during the prior 6 months, as well as smoking abstinence at 36 months.

Findings: Among 333 recalcitrant smokers, 49% reported at least one 24‐hour quit attempt during the preceding 6 months, 29% tried smoking cessation pharmacotherapy, and 5% quit smoking. Significant predictors of having at least one 24‐hour quit attempt were lower numbers of cigarettes smoked per day, being in preparation stage of change, and more pharmacotherapy‐assisted quit attempts during the original 24‐month trial. Higher motivation to quit and more previous pharmacotherapy‐assisted quit attempts significantly predicted cessation medication use. Use of varenicline was strongly associated with cessation.

Conclusions: Many recalcitrant rural smokers continue to engage in treatment and make quit attempts even in the absence of active interventions.
The proliferative effects of ghrelin on human gastric cancer AGS cells
Authors: TIAN Pei Ying , FAN Xiao Ming
Published: May 2012

OBJECTIVE:  To investigate the role of ghrelin in the gastric cancer cell line AGS and its probable mechanism.

METHODS:  Cell proliferation was detected by MTT assay after treated with ghrelin or des‐acyl ghrelin. The expression of growth hormone secretagogue receptor 1a (GHS‐R1a) and 1b (GHS‐R1b) mRNA was detected using reverse transcription polymerase chain reaction (RT‐PCR). The activity of extracellular signal‐regulated kinase 1/2 (ERK1/2) and Akt was measured by Western blot in cells either treated with ghrelin or inhibitors for ERK1/2 and phosphoinositide‐3 kinase (PI3K). The distribution of cell cycle phases was determined by flow cytometry analysis of DNA content.

RESULTS:  GHS‐R1a and GHS‐R1b mRNA were expressed in the AGS cells. Ghrelin and des‐acyl ghrelin induced AGS cell proliferation at concentrations of 1 nmol/L and 10 nmol/L but had no proliferative effect at a concentration of 100 nmol/L. The treatment of AGS cells with 10 nmol/L of ghrelin and des‐acyl ghrelin resulted in the progression of the increased cells in the S phase. ERK1/2 and Akt were activated by ghrelin and des‐acyl ghrelin. Specific ERK1/2 inhibitor PD98059 and PI3K inhibitor wortmannin reduced phosphorylation of ERK1/2 and Akt, respectively and blocked ghrelin‐ and des‐acyl ghrelin‐induced AGS cell proliferation.

CONCLUSION:  Ghrelin and des‐acyl ghrelin stimulate the proliferation of gastric cancer cells via the activation of the ERK1/2 and PI3K/Akt pathway.
Metabolic Syndrome in South Asians
Authors: Ram C. Venkata S. , Farmer John A.
Published: May 2012

Metabolic syndrome (MS) is a cluster of multiple cardio‐metabolic risk factors in the same individual. People with MS are at high risk for the development of cardiovascular disease (CVD), chronic kidney disease (CKD), and cerebrovascular disease (CeVD). The excessive presence of MS in South Asians is likely responsible for significant morbidity in this population. This review discusses the scope of MS in South Asians and measures to combat its effects by preventive and therapeutic measures. J Clin Hypertens (Greenwich). 2012;00:00–00. ©2012 Wiley Periodicals, Inc.
A Regional‐Scale Habitat Suitability Model to Assess the Effects of Flow Reduction on Fish Assemblages in Michigan Streams1
Authors: Zorn Troy G. , Seelbach Paul W. , Rutherford Edward S.
Published: May 2012

Zorn, Troy G., Paul W. Seelbach, and Edward S. Rutherford, 2012. A Regional‐Scale Habitat Suitability Model to Assess the Effects of Flow Reduction on Fish Assemblages in Michigan Streams. Journal of the American Water Resources Association (JAWRA) 48(5): 871‐895. DOI: 10.1111/j.1752‐1688.2012.00656.x

Abstract:  In response to concerns over increased use and potential diversion of Michigan’s freshwater resources, and the resulting state legislative mandate, an advisory council created an integrated assessment model to determine the potential for water withdrawals to cause an adverse resource impact to fish assemblages in Michigan’s streams. As part of this effort, we developed a model to predict how fish assemblages characteristic of different stream types would change in response to decreased stream base flows. We describe model development and use in this case study. The model uses habitat suitability information (i.e., catchment size, base‐flow yield, and July mean water temperature) for over 40 fish species to predict assemblage structure in an individual river segment under a range of base‐flow reductions. By synthesizing model runs for individual fish species at representative segments for each of Michigan’s 11 ecological stream types, we developed curves describing how typical fish assemblages in each type respond to flow reduction. Each stream type‐specific, fish response curve was used to identify streamflow reduction levels resulting in adverse resource impacts to characteristic fish populations, the regulatory standard. Used together with a statewide map of stream types, our model provided a spatially comprehensive framework for evaluating impacts of flow withdrawals on biotic communities across a diverse regional landscape.
Impacts of Dams on Flow Regimes in Three Headwater Subbasins of the Columbia River Basin, United States1
Authors: Moore Johnnie N. , Arrigoni Alicia S. , Wilcox Andrew C.
Published: May 2012

Moore, Johnnie N., Alicia S. Arrigoni, and Andrew C. Wilcox, 2012. Impacts of Dams on Flow Regimes in Three Headwater Subbasins of the Columbia River Basin, United States. Journal of the American Water Resources Association (JAWRA) 48(5): 925‐938. DOI: 10.1111/j.1752‐1688.2012.00660.x

Abstract:  We compared long‐term changes in flow regimes resulting from climate change with those resulting from dams in three matched pairs of natural and modified headwater subbasins of the Columbia River. Based on the analysis of 12 flow‐regime metrics, we found that damming had minimal effect on most quantity of flow metrics, but major effect on timing of flow metrics, especially those representing “spring runoff.” In all modified subbasins, “spring runoff” metrics occurred much earlier than natural flow (up to ∼44 days earlier for April‐July flows). Storage capacity modulated the magnitude of timing of flow‐metric changes, with the largest storage capacity leading to the most change. However, even in subbasins with low storage capacity, we found significant change in most timing of flow metrics. We also found that damming, especially in subbasins with higher storage capacity, overwhelmed climate variability in all basins for most flow metrics. This shows that reservoir operations need to be modified to more closely match the natural timing of flow regimes to promote positive ecologic response in modified rivers, even in basins where quantity of flow metrics have not changed substantially as a result of damming.
Blood pressure variables and prevalent electrocardiographic left ventricular hypertrophy in sub‐Saharan African individuals with type 2 diabetes
Authors: Dzudie Anastase , Choukem Simeon P. , Dehayem Mesmin Y. , Kengne Andre P.
Published: May 2012

Background:  The aim of the present study was to investigate whether brachial blood pressure (BP) variables (systolic BP [SBP], diastolic BP [DBP], pulse [PP] and mean arterial pressure [MAP]) are similar determinants of prevalent electrocardiographic left ventricular hypertrophy (LVH) in sub‐Saharan Africans with type 2 diabetes (T2D).

Methods:  The study included 420 individuals (49% men) with T2D who were receiving chronic care in two main referral centers in the two major cities (Douala and Yaounde) of Cameroon. Logistic regression models were used to estimate the odds ratio (OR) and 95% confidence intervals (CI) for a standard deviation (SD) higher level of SBP (25 mmHg), DBP (13), PP (18) and MAP (20) with the risk of LVH. Discrimination was assessed and compared with c‐statistics and relative integrated discrimination improvement (RIDI; %).

Results:  The multivariable adjusted OR (95% CI) for prevalent LVH with each SD higher pressure variable was 1.61 (1.22–2.11) for SBP, 1.27 (0.99–1.63) for DBP, 1.62 (1.23–2.15) for PP and 1.44 (1.11–1.87) for MAP. Comparison of c‐statistics revealed no difference in the discrimination power of models with each of the BP variables (P > 0.09). However, RIDI showed enhanced discrimination in the models when other BP variables were replaced with PP. However, this enhancement was marginal for SBP. Using BP combinations modestly improved discrimination.

Conclusions:  The best predictors of prevalent LVH in the present study population were PP and SBP, whereas DBP was the least effective predictor. These findings have implications for cardiovascular risk stratification and monitoring of risk‐reducing therapies.
One Interviewer Versus Several: Modernist and Postmodernist Perspectives in Qualitative Family Interviewing
Authors: Rosenblatt Paul C.
Published: May 2012

In the past I worked at meeting modernist research standards by carrying out qualitative family research using multiple interviewers. But different interviewers brought back different interview material, and although from a postmodern perspective that is to be expected and can be beneficial, it created several problems. As I have evolved to be more of a postmodern researcher, the modernist standards I once believed in still matter to me, but I now think that, from symbolic interaction, social construction, and other perspectives, single‐interviewer research is legitimate and, in some ways, preferable. But then I have found in my recent interview research that there are good reasons to use more than one interviewer as long as they interview together.
Examining a Brief Suicide Screening Tool in Older Adults Engaging in Risky Alcohol Use
Authors: Ribeiro Jessica D. , Braithwaite Scott R. , Pfaff Jon J. , Joiner Thomas E.
Published: May 2012

Alcohol misuse increases risk of suicidal behavior in older adults. The Depressive Symptom Inventory‐Suicidality Subscale (DSI‐SS; Metalsky & Joiner, 1997) and its relation to suicide attempt history was examined to see if it differed for older adults as a function of their alcohol use. Structural equation modeling was used in a sample (N = 1,061) of older adult outpatients to examine the scale’s measurement invariance and population heterogeneity and its relation to suicide attempt history. Analyses supported the equivalence of the DSI‐SS in risky and nonrisky drinkers. The DSI‐SS significantly predicted past suicide attempts. Findings support the viability of the DSI‐SS as suicide screening tool for older adults.
Suicidal Ideation, Depression, and Conduct Disorder in a Sample of Adolescent and Young Adult Twins
Authors: Linker Julie , Gillespie Nathan A. , Maes Hermine , Eaves Lindon , Silberg Judy L.
Published: May 2012

The co‐occurrence of suicidal ideation, depression, and conduct disturbance is likely explained in part by correlated genetic and environmental risk factors. Little is known about the specific nature of these associations. Structured interviews on 2,814 twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and Young Adult Follow‐Up (YAFU) yielded data on symptoms of depression, conduct disorder, and adolescent and young adult suicidal ideation. Univariate analyses revealed that the familial aggregation for each trait was explained by a combination of additive genetic and shared environmental effects. Suicidal ideation in adolescence was explained in part by genetic influences, but predominantly accounted for by environmental factors. A mixture of genetic and shared environmental influences explained ideation occurring in young adulthood. Multivariate analyses revealed that there are genetic and shared environmental effects common to suicidal ideation, depression, and conduct disorder. The association between adolescent suicidal ideation and CD was attributable to the same genetic and environmental risk factors for depression. These findings underscore that prevention and intervention strategies should reflect the different underlying mechanisms involving depression and conduct disorder to assist in identifying adolescents at suicidal risk.
Flowfield Measurements in a Single Row of Low Aspect Ratio Pin Fins
Authors: Ostanek Jason K. , Thole Karen A.
Published: May 2012

Pin-fin arrays are commonly used as compact heat exchangers for cooling the trailing edge of gas turbine airfoils. While much research has been devoted to the heat transfer characteristics of various pin-fin configurations, little work has been done to investigate the flowfield in pin-fin arrays. Such information may allow for further optimization of pin-fin configurations. A new pin-fin facility at large scale has been constructed to allow optical access for the use of nonintrusive measurement techniques such as laser Doppler velocimetry and time-resolved, digital particle image velocimetry. Using these techniques, the flow through a single row of pin fins having a height-to-diameter ratio of 2 and span-to-diameter ratio of 2.5 was investigated. Results showed that the length of the wake region decreased with increasing Reynolds number. At higher Reynolds numbers, Kármán vortices developed closer to the pin fins than for single, infinitely long cylinders. Transverse fluctuations correlated well with endwall heat transfer indicating that the Kármán vortices play a key role in energy transport.
Selective Roughness in the Boundary Layer to Suppress Flow-Induced Motions of Circular Cylinder at 30,000<Re<120,000
Authors: Park Hongrae , Bernitsas Michael M. , Ajith Kumar R.
Published: May 2012

A passive control means to suppress flow-induced motions (FIM) of a rigid circular cylinder in the TrSL3, high-lift, flow regime is formulated and tested experimentally. The developed method uses passive turbulence control (PTC) consisting of selectively located roughness on the cylinder surface with thickness about equal to the boundary layer thickness. The map of “PTC-to-FIM,” developed in previous work, revealed robust zones of weak suppression, strong suppression, hard galloping, and soft galloping. PTC has been used successfully to enhance FIM for hydrokinetic energy harnessing using the VIVACE Converter. PTC also revealed the potential to suppress FIM to various levels. The map is flow-direction dependent. In this paper, the “PTC-to-FIM” map is used to guide development of FIM suppression devices that are flow-direction independent and hardly affect cylinder geometry. Experiments are conducted in the Low Turbulence Free Surface Water Channel of the University of Michigan on a rigid, horizontal, circular cylinder, suspended on springs. Amplitude and frequency measurements and broad field-of-view visualization reveal complex flow structures and their relation to suppression. Several PTC designs are tested to understand the effect of PTC roughness, location, coverage, and configuration. Gradual modification of PTC parameters, leads to improved suppression and evolution of a design reducing the VIV synchronization range. Over a wide range of high reduced velocities, VIV is fully suppressed. The maximum amplitude occurring near the system’s natural frequency is reduced by about 63% compared to the maximum amplitude of the smooth cylinder.
Experimental Study to Characterize the Performance of Combined Photovoltaic/Thermal Air Collectors
Authors: Delisle Véronique , Kummert Michaël
Published: May 2012

Combined photovoltaic/thermal (PV/T) collectors show great potential for reaching the objective of net-zero energy consumption in buildings, but the number of products on the market is still very limited. One of the reasons for the slow market uptake of PV/T collectors is the absence of standardized methods to characterize their performance. Performance characterization is a challenge for PV/T collectors because of the interaction between the thermal and electrical yield. This study addresses this particular issue for PV/T air collectors used in either closed-loop or open-loop configurations. In particular, it presents the potential of the equivalent cell temperature method to determine the temperature of the PV cells in a PV/T air collector and validates models to predict the thermal performance and cell temperature for this particular type of solar collector. Indoor and outdoor experimental tests were performed on two c-Si unglazed PV/T modules. The indoor part of this procedure provided the thermal diode voltage factor and the open-circuit voltage temperature coefficient, two parameters that are essential in the calculation of the equivalent cell temperature. The outdoor procedure consisted of acquiring simultaneous electrical and thermal measurements at various inlet temperatures and flowrates. For the collector used in a closed-loop configuration, thermal efficiency models using the fluid inlet, outlet, or average temperature in the calculation of the reduced temperature provided similar results. For an open-loop configuration, a thermal efficiency model as a function of the fluid outlet flowrate was found to be more appropriate. Using selection of variable methods, it was found that a multiple linear regression model using the fluid inlet temperature, the irradiance, and the fluid outlet temperature as predictive variables could be used to estimate both the PV module back surface average temperature and the equivalent cell temperature. When using the PV temperature predicted by these models in the electrical efficiency model, both PV temperatures showed similar performance. In collectors where the PV back surface temperature is not accessible for temperature sensors mounting, the equivalent cell temperature provides a valuable alternative to be used as the PV temperature. The PV/T collector thermal and electrical performance in either closed-loop or open-loop configurations was found to be encapsulated with a series of five-plots.
Experimental Study of a Diesel Engine Performance Running on Waste Vegetable Oil Biodiesel Blend
Authors: Chokri Boubahri , Ridha Ennetta , Rachid Said , Jamel Bessrour
Published: May 2012

The main purpose of this research is to study the effect of various blends of an environmental friendly alternative fuel “methyl ester” on the performance of a heavy diesel engine. The biodiesel was obtained from a chemical process: the transesterification of waste oils (frying oils). Tests were conducted on an engine test bench in accordance to DIN 2020 standards. Results obtained demonstrate that the biodiesel gives very interesting ecological advantages but engine performance was reduced slightly comparatively to those obtained with a pure diesel fuel. We have noted about 5% decrease in power and torque and about 2% in Nox emission for every 10% of biodiesel blend added comparatively to pure diesel. However, the use of biodiesel has slightly increased specific fuel consumption (about 6% for every 10% of biodiesel blend added).
Tracking Cooper Pairs in a Cuprate Superconductor by Ultrafast Angle-Resolved Photoemission
Authors: Smallwood Christopher L. , Hinton James P. , Jozwiak Christopher , Zhang Wentao , Koralek Jake D. , Eisaki Hiroshi , Lee Dung-Hai , Orenstein Joseph , Lanzara Alessandra
Published: May 2012

Dissecting Cooper Pairs

Angle-resolved photoemission spectroscopy (ARPES) is used in the study of the electronic structure of complex materials. Recently, time-resolved ARPES has become possible, where the state of the system is excited by a short “pump” pulse, and ARPES is performed using a second “probe” pulse applied after varying times.

Smallwood
et al.

(p.
1137
) used this technique to study the recombination of Cooper pairs—the fundamental charge carriers in superconductors—in a cuprate high-temperature superconductor.
Rocket Launcher Mechanism of Collaborative Actin Assembly Defined by Single-Molecule Imaging
Authors: Breitsprecher Dennis , Jaiswal Richa , Bombardier Jeffrey P. , Gould Christopher J. , Gelles Jeff , Goode Bruce L.
Published: May 2012

See How They Grow

Controlled assembly and disassembly of the actin cytoskeleton is essential for processes such as cell motility, cytokinesis, and tumor metastasis. The formation of new actin filaments appears to involve the protein formin paired with another actin assembly-promoting factor.

Breitsprecher
et al.

(p.
1164
) used triplecolor single-molecule fluorescence microscopy to visualize actin assembly promoted by the formin, mDia1, and the tumor-suppressor, adenomatous polyposis coli (APC). The two assembly factors interacted directly to initiate filament assembly, after which mDia1 moved with the growing barbed ends while APC remained at the site of nucleation.
The Amyloid Precursor Protein Has a Flexible Transmembrane Domain and Binds Cholesterol
Authors: Barrett Paul J. , Song Yuanli , Van Horn Wade D. , Hustedt Eric J. , Schafer Johanna M. , Hadziselimovic Arina , Beel Andrew J. , Sanders Charles R.
Published: May 2012

Insights into Amyloidogenesis

The amyloid-β (Aβ) peptides associated with Alzheimer's disease are generated by cleavage of the transmembrane C-terminal domain (C99) of the amyloid precursor protein by the enzyme γ-secretase.

Barrett
et al.

(p.
1168
) used nuclear magnetic resonance (NMR) and electron paramagnetic resonance spectroscopy to show that C99 contains surface-associated N- and C-terminal helices and a flexibly curved transmembrane helix that is well suited to processive cleavage by γ-secretase. Elevated cholesterol levels have been found to increase Aβ generation. NMR titration together with mutagenesis revealed a binding site for cholesterol within C99 that included a motif previously implicated in protein oligomerization.
Theory Untangles the High-Resolution Infrared Spectrum of the
ortho
-H
2
-CO van der Waals Complex
Authors: Jankowski Piotr , McKellar A. R. W. , Szalewicz Krzysztof
Published: May 2012

Untangling a Spectral Thicket

Atoms and molecules absorb characteristic frequencies of ligh; however, assigning the spectra of certain molecules remains a challenge. For example, the loosely bound complex of CO with H2 produces a dense thicket of measured spectral lines that has resisted elucidation for over a decade. Now,

Jankowski
et al.

(p.
1147
) provide detailed theoretical calculations that match the observed pattern and thereby elucidate the vibrational and rotational states in play. The result may ultimately help to tease out the collisional dynamics of H
2
and CO in the interstellar medium.
Understanding Sediments—Reducing Tsunami Risk
Authors: Weiss Robert , Bourgeois Joanne
Published: May 2012

Knowledge of the processes that drive tsunami sediment erosion and deposition can help to determine and mitigate tsunami risk.
Imported Klebsiella pneumoniae Carbapenemase-Producing K. pneumoniae Clones in a Greek Hospital: Impact of Infection Control Measures for Restraining Their Dissemination
Authors: Poulou Aggeliki , Voulgari Evangelia , Vrioni Georgia , Xidopoulos Grigorios , Pliagkos Aris , Chatzipantazi Vassiliki , Markou Fani , Tsakris Athanassios
Published: May 2012

The recent emergence of carbapenemase-producing
Enterobacteriaceae
strains represents a major threat for hospitalized patients. We document the dissemination and control of carbapenemase-producing
Klebsiella pneumoniae
clones in a Greek hospital. During a 3-year study period (January 2009 to December 2011), carbapenemase-producing
K. pneumoniae
strains were isolated from clinical samples from 73 individual patients. Phenotyping and molecular testing confirmed that 52 patients were infected with
K. pneumoniae
carbapenemase 2 (KPC-2) producers, 12 were infected with VIM-1 producers, and the remaining 9 were infected with isolates producing both KPC-2 and VIM-1 enzymes. Twenty-eight of these clinical cases were characterized as imported health care associated, and 23 of these were attributed to KPC producers and 5 were attributed to KPC and VIM producers. The remaining 45 cases were deemed hospital acquired. In the second year of the study, intensified infection control intervention was implemented, followed by active surveillance and carrier isolation in the third year. The incidence of carbapenemase-producing
K. pneumoniae
patient cases decreased from 0.52/1,000 patient days in 2009 to 0.32/1,000 patient days in 2010 (
P
= 0.075). Following these additional infection control measures, the incidence fell to 0.21/1,000 patient days in 2011 and differed significantly from that in 2009 (
P
= 0.0028). Despite the fact that the imported cases of carbapenemase-producing
K. pneumoniae
were equally distributed over this 3-year period, the incidence of hospital-acquired cases decreased from 0.36/1,000 patient days in 2009 to 0.19/1,000 patient days in 2010 (
P
= 0.058) and to 0.1/1,000 patient days in 2011 (
P
= 0.0012). Our findings suggest that rigorous infection control measures and active surveillance can effectively reduce the incidence of secondary transmission due to KPC-producing pathogens.
Detection of Wolbachia DNA in Blood for Diagnosing Filaria-Associated Syndromes in Cats
Authors: Turba Maria Elena , Zambon Elisa , Zannoni Augusta , Russo Samanta , Gentilini Fabio
Published: May 2012

A fundamental role for the endosymbiotic bacteria
Wolbachia pipientis
in the pathogenesis of
Dirofilaria immitis
infections has emerged in recent years. Diagnostic opportunities arising from this breakthrough have not yet been fully exploited. This study was aimed at developing conventional and real-time PCR assays to carry out a molecular survey in a convenience sample of cats living in an area where
D. immitis
is endemic and to evaluate the detection of bacterial DNA in blood as a surrogate assay for diagnosing filaria-associated syndromes in cats. COI and FtsZ loci were used as targets for
D. immitis
and
Wolbachia
PCR assays, respectively, and real-time TaqMan PCR assays were used only for
Wolbachia
. A convenience sample of 307 disease-affected or healthy cats examined at a University facility were PCR tested, and their medical records were investigated. Conventional nested PCR for
Wolbachia
amplified the endosymbionts of both
D. immitis
and
D. repens
, while real-time PCR was highly specific only for the former. Observed prevalences of 0.3 and 10.4% were found using conventional nested PCR assays for
D. immitis
and real-time PCR for
Wolbachia
, respectively. Similar prevalences were established using the Wolbachia nested PCR (98% concordance with real-time PCR). The group of
Wolbachia
-positive samples had a significantly higher proportion of subjects with respiratory signs (29.0% versus 9.7%;
P
= 0.002). The findings of this study indicate that a highly sensitive PCR assay can be used to detect the
Wolbachia
organism in the peripheral blood of cats with respiratory signs.
Diagnostic Value of Conjunctival Swab Sampling Associated with Nested PCR for Different Categories of Dogs Naturally Exposed to Leishmania infantum Infection
Authors: Di Muccio Trentina , Veronesi Fabrizia , Antognoni Maria Teresa , Onofri Andrea , Piergili Fioretti Daniela , Gramiccia Marina
Published: May 2012

The objective of the present study was to evaluate the diagnostic performance of a noninvasive assay, conjunctival swab (CS) nested-PCR (n-PCR), for diagnosing canine leishmaniasis (CanL) in different stages of infection in comparison to the performance of the indirect immunofluorescence antibody test (IFAT), lymph node microscopy, and buffy coat n-PCR. To this end, we performed a cross-sectional survey among 253 nonselected dogs in areas of endemicity in central Italy. We also performed a longitudinal study of CS n-PCR among 20 sick dogs undergoing antileishmanial treatment. In the first study, among the 72 animals that were positive by at least one test (28.45%), CS n-PCR showed the best relative performance (76.38%), with a high concordance in comparison to standard IFAT serology (κ = 0.75). The highest positivity rates using CS n-PCR were found in asymptomatic infected dogs (84.2%) and sick dogs (77.8%); however, the sensitivity of the assay was not associated with the presence of clinical signs. In the follow-up study on treated sick dogs, CS n-PCR was the most sensitive assay, with promising prognostic value for relapses. The univariate analysis of risk factors for CanL based on CS n-PCR findings showed a significant correlation with age (
P
= 0.012), breed size (
P
= 0.026), habitat (
P
= 4.9 × 10
−4
), and previous therapy (
P
= 0.014). Overall, the results indicated that CS n-PCR was the most sensitive assay of the less invasive diagnostic methods and could represent a good option for the early and simple diagnosis of CanL infection in asymptomatic animals and for monitoring relapses in drug-treated dogs.
Suppression of Transcription Factor Early Growth Response 1 Reduces Herpes Simplex Virus 1-Induced Corneal Disease in Mice
Authors: Yao Hui-Wen , Chen Shih-Heng , Li Ching , Tung Yuk-Ying , Chen Shun-Hua
Published: May 2012

Herpes simplex virus 1 replication initiates angiogenesis and inflammation in the cornea. This can result in herpetic stromal keratitis (HSK), which is a leading cause of infection-induced corneal blindness. Host cellular factors mediate the progression of HSK, but little is known about these cellular factors and their mechanisms of action. We show here that the expression of the cellular transcription factor early growth response 1 (Egr-1) in HSV-1-infected mouse corneas was enhanced. Enhanced Egr-1 expression aggravated HSK by increasing viral replication and subsequent neovascularization with high levels of potent angiogenic factors, fibroblast growth factor 2, and vascular endothelial growth factor. Furthermore, Egr-1 deficiency due to a targeted disruption of the gene or knockdown of Egr-1 expression topically using a DNA-based enzyme significantly reduced HSK by decreasing both viral replication and the angiogenic response. The present study provides the first evidence that endogenous Egr-1 aggravates HSK and that blocking Egr-1 reduces corneal damage.
Marek's Disease Viral Interleukin-8 Promotes Lymphoma Formation through Targeted Recruitment of B Cells and CD4
+
CD25
+
T Cells
Authors: Engel Annemarie T. , Selvaraj Ramesh K. , Kamil Jeremy P. , Osterrieder Nikolaus , Kaufer Benedikt B.
Published: May 2012

Marek's disease virus (MDV) is a cell-associated and highly oncogenic alphaherpesvirus that infects chickens. During lytic and latent MDV infection, a CXC chemokine termed viral interleukin-8 (vIL-8) is expressed. Deletion of the entire vIL-8 open reading frame (ORF) was shown to severely impair disease progression and tumor development; however, it was unclear whether this phenotype was due to loss of secreted vIL-8 or of splice variants that fuse exons II and III of vIL-8 to certain upstream open reading frames, including the viral oncoprotein Meq. To specifically examine the role of secreted vIL-8 in MDV pathogenesis, we constructed a recombinant virus, vΔMetvIL-8, in which we deleted the native start codon from the signal peptide encoding exon I. This mutant lacked secreted vIL-8 but did not affect Meq–vIL-8 splice variants. Loss of secreted vIL-8 resulted in highly reduced disease and tumor incidence in animals infected with vΔMetvIL-8 by the intra-abdominal route. Although vΔMetvIL-8 was still able to spread to naïve animals by the natural route, infection and lymphomagenesis in contact animals were severely impaired.
In vitro
assays showed that purified recombinant vIL-8 efficiently binds to and induces chemotaxis of B cells, which are the main target for lytic MDV replication, and also interacts with CD4
+
CD25
+
T cells, known targets of MDV transformation. Our data provide evidence that vIL-8 attracts B and CD4
+
CD25
+
T cells to recruit targets for both lytic and latent infection.
Efficient Human Cytomegalovirus Reactivation Is Maturation Dependent in the Langerhans Dendritic Cell Lineage and Can Be Studied using a CD14+Experimental Latency Model
Authors: Huang Margaret M. , Kew Verity G. , Jestice Kevin , Wills Mark R. , Reeves Matthew B.
Published: May 2012

Studies from a number of laboratories have shown that the myeloid lineage is prominent in human cytomegalovirus (HCMV) latency, reactivation, dissemination, and pathogenesis. Existing as a latent infection in CD34+progenitors and circulating CD14+monocytes, reactivation is observed upon differentiation to mature macrophage or dendritic cell (DC) phenotypes. Langerhans' cells (LCs) are a subset of periphery resident DCs that represent a DC population likely to encounter HCMV early during primary infection. Furthermore, we have previously shown that CD34+derived LCs are a site of HCMV reactivationex vivo. Accordingly, we have utilized healthy-donor CD34+cells to study latency and reactivation of HCMV in LCs. However, the increasing difficulty acquiring healthy-donor CD34+cells—particularly from seropositive donors due to the screening regimens used—led us to investigate the use of CD14+monocytes to generate LCs. We show here that CD14+monocytes cultured with transforming growth factor β generate Langerin-positive DCs (MoLCs). Consistent with observations using CD34+derived LCs, only mature MoLCs were permissive for HCMV infection. The lytic infection of mature MoLCs is productive and results in a marked inhibition in the capacity of these cells to promote T cell proliferation. Pertinently, differentiation of experimentally latent monocytes to the MoLC phenotype promotes reactivation in a maturation and interleukin-6 (IL-6)-dependent manner. Intriguingly, however, IL-6-mediated effects were restricted to mature LCs, in contrast to observations with classical CD14+derived DCs. Consequently, elucidation of the molecular basis behind the differential response of the two DC subsets should further our understanding of the fundamental mechanisms important for reactivation.
Parenteral Pethidine for labour pain relief and substance use disorder: 20-year follow-up cohort study in offspring
Authors: Pereira Robert Rodrigues , Kanhai Humphrey , Rosendaal Frits , van Dommelen Paula , Swaab Dick , Rodrigues Pereira Erik , van de Wetering Ben
Published: May 2012

Objective

To determine whether use of intrapartum Pethidine pain analgesia increases the risk for substance use disorder in adult offspring.

Design

Analysis of data from a cohort study.

Setting

Academic hospital in Leiden, the Netherlands.

Participants

133 cases and 164 control individuals, aged 18–20 years at follow-up.

Main outcome measure

Incidence of substance use disorder or use of alcohol and tobacco.

Results

The lifetime use of addictive substances in children exposed to intrapartum Pethidine analgesia was 45% of 133 children versus 48% of 164 not-exposed subjects (adjusted OR=0.79, 95% CI 0.48 to 1.29). Recent use of alcohol, tobacco and hard drugs showed no statistical difference either.

Conclusion

Pethidine for labour pain medication appears not to be associated with substance misuse or smoking in later life.
Disability pension among young women in Sweden, with special emphasis on family structure: a dynamic cohort study
Authors: Floderus Birgitta , Hagman Maud , Aronsson Gunnar , Gustafsson Klas , Marklund Staffan , Wikman Anders
Published: May 2012

Objectives

The influence of family structure on the risk of going on disability pension (DP) was investigated among young women by analysing a short-term and long-term effect, controlling for potential confounding and the ‘healthy mother effect’.

Design and participants

This dynamic cohort study comprised all women born in Sweden between 1960 and 1979 (1.2 million), who were 20–43 years of age during follow-up. Their annual data were retrieved from national registers for the years 1993–2003. For this period, data on family structure and potential confounders were related to the incidence of DP the year after the exposure assessment. Using a modified version of the COX proportional hazard regression, we took into account changes in the study variables of individuals over the years. In addition, a 5-year follow-up was used.

Results

Cohabiting working women with children showed a decreased risk of DP in a 1-year perspective compared with cohabiting working women with no children, while the opposite was indicated in the 5-year follow-up. Lone working women with children had an increased risk of DP in both the short-term and long-term perspective. The risk of DP tended to increase with the number of children for both cohabiting and lone working women in the 5-year follow-up.

Conclusions

The study suggests that parenthood contributes to increasing the risk of going on DP among young women, which should be valuable knowledge to employers and other policy makers. It remains to be analysed to what extent the high numbers of young women exiting from working life may be counteracted by (1) extended gender equality, (2) fewer work hours among fathers and mothers of young children and (3) by financial support to lone women with children.
Provision of palliative care for life-limiting disease in a low income country national hospital setting: how much is needed?
Authors: Lewington Jane , Namukwaya Elizabeth , Limoges Julie , Leng Mhoira , Harding Richard
Published: May 2012

Objectives

This study aimed to measure the magnitude of palliative care needs among hospital inpatients. Objectives were to: (1) determine the point prevalence of inpatients with active life-limiting disease and (2) describe multidimensional need for palliative care among these patients.

Methods

The study was a hospital inpatient census in Uganda. Patient notes were surveyed and those patients identified as having an active life-limiting disease were interviewed. Multidimensional palliative care need was assessed using the African Palliative Care Association (APCA) African Palliative Outcome Scale (POS).

Results

122/267 (46%) patient notes were found to indicate an active life-limiting disease. Diagnoses were; HIV/AIDS (74/122, 61%), cancer (22/122, 18%), heart failure (11/122, 9%), renal failure (11/122, 9%), liver failure (3/122, 2%) and chronic obstructive pulmonary disease (1/122, 1%). A total of 78/122 patients consented to be interviewed. Most patients reported multidimensional need in the three most negative of six categories for any APCA African POS question (75/78, 96%). Social problems included an inability to work (72/78, 92%), having unaffordable medical expenses (39/78, 50%) and limited access to food (11/78, 14%). Of those with a faith (76/78), more than a third (29/78, 38%) expressed the need for increased faith support.

Conclusions

The prevalence of active life-limiting disease reported here (46%) is greater than in comparable European studies (5–23%).This reflects the sub-Saharan increased disease prevalence, presentation at a later stage and limited access to curative therapies. There is need for symptom control, food, financial assistance and spiritual support. Service development should be tailored to meet these needs.