bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexible bronchoscopic management of benign tracheal stenosis: long term follow-up of 115 patients
Authors: Rahman Nader Abdel , Fruchter Oren , Shitrit David , Fox Benjamin D , Kramer Mordechai R
Published: January 2010

Background

Management of benign tracheal stenosis (BTS) varies with the type and extent of the disease and influenced by the patient's age and general health status, hence we sought to investigate the long-term outcome of patients with BTS that underwent minimally invasive bronchoscopic treatment.

Methods

Patients with symptomatic BTS were treated with flexible bronchoscopy therapeutic modalities that included the following: balloon dilatation, laser photo-resection, self-expanding metal stent placement, and High-dose rate endobronchial brachytherapy used in cases of refractory stent-related granulation tissue formation.

Results

A total of 115 patients with BTS and various cardiac and respiratory co-morbidities with a mean age of 61 (range 40-88)were treated between January 2001 and January 2009. The underlining etiologies for BTS were post - endotracheal intubation (N = 76) post-tracheostomy (N = 30), Wegener's granulomatosis (N = 2), sarcoidosis (N = 2), amyloidosis (N = 2) and idiopathic BTS (N = 3). The modalities used were: balloon dilatation and laser treatment (N = 98). Stent was placed in 33 patients of whom 28 also underwent brachytherapy. Complications were minor and mostly included granulation tissue formation. The overall success rate was 87%. Over a median follow-up of 51 months (range 10-100 months), 30 patients (26%) died, mostly due to exacerbation of their underlying conditions.

Conclusions

BTS in elderly patients with co-morbidities can be safely and effectively treated by flexible bronchoscopic treatment modalities. The use of HDR brachytherapy to treat granulation tissue formation following successful airway restoration is promising.
Amyloid-β-Acetylcholinesterase complexes potentiate neurodegenerative changes induced by the Aβ peptide. Implications for the pathogenesis of Alzheimer's disease
Authors: Dinamarca Margarita C , Sagal Juan P , Quintanilla Rodrigo A , Godoy Juan A , Arrázola Macarena S , Inestrosa Nibaldo C
Published: January 2010

The presence of amyloid-β (Aβ) deposits in selected brain regions is a hallmark of Alzheimer's disease (AD). The amyloid deposits have "chaperone molecules" which play critical roles in amyloid formation and toxicity. We report here that treatment of rat hippocampal neurons with Aβ-acetylcholinesterase (Aβ-AChE) complexes induced neurite network dystrophia and apoptosis. Moreover, the Aβ-AChE complexes induced a sustained increase in intracellular Ca2+ as well as a loss of mitochondrial membrane potential. The Aβ-AChE oligomers complex also induced higher alteration of Ca2+ homeostasis compared with Aβ-AChE fibrillar complexes. These alterations in calcium homeostasis were reversed when the neurons were treated previously with lithium, a GSK-3β inhibitor; Wnt-7a ligand, an activator for Wnt Pathway; and an N-methyl-D-aspartate (NMDA) receptor antagonist (MK-801), demonstrating protective roles for activation of the Wnt signaling pathway as well as for NMDA-receptor inhibition. Our results indicate that the Aβ-AChE complexes enhance Aβ-dependent deregulation of intracellular Ca2+ as well as mitochondrial dysfunction in hippocampal neurons, triggering an enhanced damage than Aβ alone. From a therapeutic point of view, activation of the Wnt signaling pathway, as well as NMDAR inhibition may be important factors to protect neurons under Aβ-AChE attack.
Seroprevalence of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in Danish horses
Authors: Hansen Marie GB , Christoffersen Mette , Thuesen Line R , Petersen Morten R , Bojesen Anders M
Published: January 2010

Background

Borrelia burgdorferisensu lato andAnaplasma phagocytophilumare able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence ofB. burgdorferisensu lato andA. phagocytophilumin Danish horses.

Methods

A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies againstB. burgdorferisensu lato andA. phagocytophilumby the use of the SNAP®4DX®ELISA test.

Results

Overall, 29.0% of the horses were seropositive forB. burgdorferisensu lato whereas 22.3% were seropositive forA. phagocytophilum.

Conclusions

Antibodies againstB burgdorferisensu lato andA. phagocytophilumare commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.
The influence of pore fluids and frequency on apparent effective stress behavior of seismic velocities
Authors: Mavko Gary , Vanorio Tiziana
Published: January 2010

Although poroelastic theory predicts that the effective stress coefficient equals unity for elastic moduli in monomineralic rocks, some rock elastic wave velocities measured at ultrasonic frequencies have effective stress coefficients less than one. Laboratory effective stress behavior for P-waves is often different than S-waves. Furthermore, laboratory ultrasonic velocities almost always reflect high-frequency artifacts associated with pore fluids, including an increase in velocities and flattening of velocity-versus-pressure curves. We have investigated the impact of pore fluids and frequency on the observed effective stress coefficient for elastic wave velocities by developing a model that calculates pore-fluid effects on velocity, including high-frequency squirt dispersion, and we have compared the model’s predictions with laboratory data. We modeled a rock frame with penny-shaped cracks for three situations: vacuum dry, saturated with helium, and saturated with brine. Even if the frame modulus depends only on the differential stress, the saturated-rock effective stress coefficient is predicted to be significantly less than one at ultrasonic frequencies because of two effects: an increase in the fluid bulk modulus with increasing pressure and the contribution of high-frequency squirt dispersion. The latter effect is most significant in soft fluids (helium in this experiment) in which the fluid-bulk modulus is less than or comparable to the thin-crack pore stiffness.
Predicting permeability and gas production of hydraulically fractured tight sands from microseismic data
Authors: Grechka Vladimir , Mazumdar Prajnajyoti , Shapiro Serge A.
Published: January 2010

The main objective of hydraulic well stimulation is creating fractures in a tight rock that enhance its natural permeability and make hydrocarbon production economic. Because the geometry of fractures and the permeability of treated formation influence the subsequent production, their assessment is important for the development of tight-gas fields. The fracture shapes and orientations are inferred conventionally from microseismic data acquired in the process of well stimulation, but the same data also can be used to estimate the formation permeability. We have compared two techniques for permeability estimation that utilize different aspects of information contained in the observed microseismicity. We applied those techniques to data recorded in the course of the hydraulic fracturing of four wells drilled in the Pinedale Field, Wyoming, U.S.A. Then we used the obtained permeabilities to predict the gas rates from 20 treatment stages at which the number of identified microseismic events was sufficient to perform our analysis. The predictions of both techniques correlate with production and allow us to establish the characteristics of rocks and hydraulic fractures that make good producers at Pinedale.
Erythropoietin elevates but not voluntary wheel running in mice
Authors: Kolb E. M. , Kelly S. A. , Middleton K. M. , Sermsakdi L. S. , Chappell M. A. , Garland T.
Published: January 2010

Voluntary activity is a complex trait, comprising both behavioral (motivation, reward) and anatomical/physiological (ability) elements. In the present study, oxygen transport was investigated as a possible limitation to further increases in running by four replicate lines of mice that have been selectively bred for high voluntary wheel running and have reached an apparent selection limit. To increase oxygen transport capacity, erythrocyte density was elevated by the administration of an erythropoietin (EPO) analogue. Mice were given two EPO injections, two days apart, at one of two dose levels (100 or 300 μg kg–1). Hemoglobin concentration ([Hb]), maximal aerobic capacity during forced treadmill exercise () and voluntary wheel running were measured. [Hb] did not differ between high runner (HR) and non-selected control (C) lines without EPO treatment. Both doses of EPO significantly (P<0.0001) increased [Hb] as compared with sham-injected animals, with no difference in [Hb] between the 100 μg kg–1 and 300 μg kg–1 dose levels (overall mean of 4.5 g dl–1 increase). EPO treatment significantly increased by ∼5% in both the HR and C lines, with no dose × line type interaction. However, wheel running (revolutions per day) did not increase with EPO treatment in either the HR or C lines, and in fact significantly decreased at the higher dose in both line types. These results suggest that neither [Hb] per se nor is limiting voluntary wheel running in the HR lines. Moreover, we hypothesize that the decrease in wheel running at the higher dose of EPO may reflect direct action on the reward pathway of the brain.
Substratum cavities affect growth-plasticity, allometry, movement and feeding rates in the sea urchinStrongylocentrotus purpuratus
Authors: Hernández J. C. , Russell M. P.
Published: January 2010

We assessed the influence of rock cavities, or pits, on the growth dynamics and behavior of the purple sea urchin, Strongylocentrotus purpuratus. In a paired-designed, laboratory experiment, sea urchins were assigned to sandstone blocks that were either ‘Flat’ or had a ‘Pit’ drilled into the center. At the start, both groups were approximately the same shape and size. In just 2 months, the shapes of the tests were significantly different between the two treatments, with the Pit urchins having an increased height:diameter profile. This result demonstrates the plastic nature of the sea urchin test and that, despite its apparent rigidity, it is capable of deforming during growth. In addition, the presence of pits modified behavior and food consumption as well as allometric growth of the test and Aristotle's lantern. Sea urchins on Pit sandstone blocks tended to stay in the cavities and not move about the flat areas, whereas individuals on Flat blocks changed position. Sea urchins in the Pit treatment consumed less food and had relatively larger demipyramids (the ‘jaw’ ossicle in Aristotle's lantern). These morphological and allometric changes occurred over a short time-period (8–20 weeks). We conclude that microhabitat is an important factor in controlling the behavior and growth dynamics of the bioeroding sea urchin S. purpuratus.
Approaching the evolutionary advantage of ancillary types of haemoglobin in Daphnia magna by simulation of oxygen supply
Authors: Moenickes S. , Richter O. , Pirow R.
Published: January 2010

The planktonic crustacean Daphnia magna synthesizes haemoglobin (Hb) macromolecules of variant subunit composition and oxygen affinity. This is one of the strategies by which the animals cope with variations in environmental conditions such as ambient oxygen tension. The enrichment of high-affinity Hb molecules in the haemolymph of hypoxia-exposed animals is thought to reduce Hb synthesis costs due to an enhanced transport efficiency of these molecules in comparison to the low-affinity Hb molecules. How great this economic advantage is, and under which conditions this benefit disappears, is still not fully understood. Here we implemented a rigorously simplified model of the daphnid body and described the transport of oxygen from the environment via the haemolymph to the tissues in terms of the convection–diffusion–reaction equation. The model was validated by comparing various model predictions with experimental data. A sensitivity analysis was used to evaluate the influence of parameter uncertainties on the model predictions. Cost–benefit analysis revealed in which way at the system's level the increase in Hb oxygen affinity improves the oxygen loading at the respiratory surfaces and impairs the release of oxygen to the tissues. The benefit arising from the improved oxygen loading exceeds the disadvantage of impaired unloading only under conditions where the ambient oxygen tension is critically low and the Hb concentration is high. The low-affinity Hb, on the other hand, provides an advantage given that the Hb concentration is low and the ambient oxygen tension is well above the critical level. Computer-aided modelling and simulation therefore provide valuable mechanistic insights into the driving forces that could have shaped the evolution of globin genes in daphnids.
Characterization of ion transport in the isolated epipodite of the lobsterHomarus americanus
Authors: Lucu Č. , Towle D. W.
Published: January 2010

Unfolded epipodite isolated from American lobsters (Homarus americanus) acclimated to dilute seawater was mounted in an Ussing-type chamber for ion transport studies. The split epipodite is an electrically polarized, one-cell-layer epithelium supported with cuticle. Under open-circuit conditions, the transepithelial potential was –4.2±1.0 mV (N=38). In the short-circuited epithelium, the current averaged over all of the preparations was –185.4±20.2 A cm–2 (N=38) with a high conductance of 55.2±11.4 mS cm–2 (N=38), typical for a leaky epithelium. The Na:Cl absorptive flux ratio was 1:1.6; ion substitution experiments indicated that the transport of Na+ and Cl– is coupled. Basolateral application of the Cl– channel blockers 5-nitro-2-(3-phenylpropylamino) benzoate (NPPB) and niflumic acid (NFA) dose-dependently inhibited short-circuit current (ISC). Secretory K+ (Rb+) fluxes exceeded influxes and were inhibited by the Na+/K+-ATPase inhibitor ouabain and the K+ channel blocker cesium. Western blot analysis showed that Na+/K+-ATPase α-subunit protein was more highly expressed in the epipodite of lobsters acclimated to 20 p.p.t. compared with animals acclimated to seawater (34 p.p.t.). 3-Isobutyl-1-methyl-xanthine (IBMX) stimulated a negative ISC and enhanced apical secretory K+ flux. Basolateral application of NPPB inhibited JRbB→A fluxes, suggesting the interaction of K+ channels with NPPB-sensitive Cl– channels. The results are summarized in a transport model, suggesting apical Na+/K+/2Cl– co-transport, a dominant apical K+-secreting channel and basolaterally located Cl– and K+ channels. This study represents the first comprehensive characterization of ion transport processes across the lobster epipodite epithelium and indeed in any tissue within the branchial cavity of the American lobster.
Aquaporin expression dynamics in osmoregulatory tissues of Atlantic salmon during smoltification and seawater acclimation
Authors: Tipsmark C. K. , Sørensen K. J. , Madsen S. S.
Published: January 2010

Osmotic balance in fish is maintained through the coordinated regulation of water and ion transport performed by epithelia in intestine, kidney and gill. In the current study, six aquaporin (AQP) isoforms found in Atlantic salmon (Salmo salar) were classified and their tissue specificity and mRNA expression in response to a hyperosmotic challenge and during smoltification were examined. While AQP-1a was generic, AQP-1b had highest expression in kidney and AQP-3 was predominantly found in oesophagus, gill and muscle. Two novel teleost isoforms, AQP-8a and -8b, were expressed specifically in liver and intestinal segments, respectively. AQP-10 was predominantly expressed in intestinal segments, albeit at very low levels. Transfer from freshwater (FW) to seawater (SW) induced elevated levels of intestinal AQP-1a, -1b and -8b mRNA, whereas only AQP-8b was stimulated during smoltification. In kidney, AQP-1a, -3 and -10 were elevated in SW whereas AQP-1b was reduced compared with FW levels. Correspondingly, renal AQP-1a and -10 peaked during smoltification in April and March, respectively, as AQP-1b and AQP-3 declined. In the gill, AQP-1a and AQP-3 declined in SW whereas AQP-1b increased. Gill AQP-1a and -b peaked in April, whereas AQP-3 declined through smoltification. These reciprocal isoform shifts in renal and gill tissues may be functionally linked with the changed role of these organs in FW compared with SW. The presence and observed dynamics of the AQP-8b isoform specifically in intestinal sections suggest that this is a key water channel responsible for water uptake in the intestinal tract of seawater salmonids.
Deep supercooling, vitrification and limited survival to –100°C in the Alaskan beetleCucujus clavipes puniceus(Coleoptera: Cucujidae) larvae
Authors: Sformo T. , Walters K. , Jeannet K. , Wowk B. , Fahy G. M. , Barnes B. M. , Duman J. G.
Published: January 2010

Larvae of the freeze-avoiding beetle Cucujus clavipes puniceus (Coleoptera: Cucujidae) in Alaska have mean supercooling points in winter of –35 to –42°C, with the lowest supercooling point recorded for an individual of –58°C. We previously noted that some larvae did not freeze when cooled to –80°C, and we speculated that these larvae vitrified. Here we present evidence through differential scanning calorimetry that C. c. puniceus larvae transition into a glass-like state at temperatures <–58°C and can avoid freezing to at least –150°C. This novel finding adds vitrification to the list of insect overwintering strategies. While overwintering beneath the bark of fallen trees, C. c. puniceus larvae may experience low ambient temperatures of around –40°C (and lower) when microhabitat is un-insulated because of low snow cover. Decreasing temperatures in winter are correlated with loss of body water from summer high levels near 2.0 to winter lows near 0.4 mg mg–1 dry mass and concomitant increases in glycerol concentrations (4–6 mol l–1) and thermal hysteresis. Finally, we provide direct evidence that Cucujus from Wiseman, Alaska, survive temperatures to –100°C.
Effects of cadmium exposure and intermittent anoxia on nitric oxide metabolism in eastern oysters,Crassostrea virginica
Authors: Ivanina A. V. , Eilers S. , Kurochkin I. O. , Chung J. S. , Techa S. , Piontkivska H. , Sokolov E. P. , Sokolova I. M.
Published: January 2010

Nitric oxide (NO) is an intracellular signaling molecule synthesized by a group of enzymes called nitric oxide synthases (NOS) and involved in regulation of many cellular functions including mitochondrial metabolism and bioenergetics. In invertebrates, the involvement of NO in bioenergetics and metabolic responses to environmental stress is poorly understood. We determined sensitivity of mitochondrial and cellular respiration to NO and the effects of cadmium (Cd) and intermittent anoxia on NO metabolism in eastern oysters, Crassostrea virginica. NOS activity was strongly suppressed by exposure to 50 μg l–1 Cd for 30 days (4.76 vs 1.19 pmol NO min–1 mg–1 protein in control and Cd-exposed oysters, respectively) and further decreased during anoxic exposure in Cd-exposed oysters but not in their control counterparts. Nitrate/nitrite content (indicative of NO levels) decreased during anoxic exposure to less than 10% of the normoxic values and recovered within 1 h of re-oxygenation in control oysters. In Cd-exposed oysters, the recovery of the normoxic NO levels lagged behind, reflecting their lower NOS activity. Oyster mitochondrial respiration was inhibited by exogenous NO, with sensitivity on a par with that of mammalian mitochondria, and ADP-stimulated mitochondrial respiration was significantly more sensitive to NO than resting respiration. In isolated gill cells, manipulations of endogenous NOS activity either with a specific NOS inhibitor (aminoguanidine) or a NOS substrate (l-arginine) had no effect on respiration, likely due to the fact that mitochondria in the resting state are relatively NO insensitive. Likewise, Cd-induced stimulation of cellular respiration did not correlate with decreased NOS activity in isolated gill cells. High sensitivity of phosphorylating (ADP-stimulated) oyster mitochondria to NO suggests that regulation of bioenergetics is an evolutionarily conserved function of NO and that NO-dependent regulation of metabolism may be most prominent under the conditions of high metabolic flux when the ADP-to-ATP ratio is high.
Contested Loyalties: Dissident Identity Organizations, Institutions, and Social Movements
Authors: Kretschmer Kelsy
Published: January 2010

In this article, the author investigates the innovative survival strategies of two organizations, both of which claim loyalty to parent institutions while simultaneously attempting to undermine those institutions in a larger political arena. The author asks how and why these organizations are able to maintain this precarious position. Findings indicate that the organizations manage to balance institutional insider and outsider status in three main ways: By reinterpreting key institutional texts in ways that support their own beliefs, by claiming to represent the majority of institutional membership, and by distancing themselves from the “corrupted” institutional elites. Their institutional loyalty claims help create a niche in a broader social movement and attracts support from external institutional opponents. But their dual identity also puts them at particular risk of being isolated from supportive communities. In general, these organizations shed light on the creative ways organizations can meet (sometimes) conflicting resource and legitimacy needs.
Formal and Informal Network Coupling and its Relationship to Workplace Attachment
Authors: Kuipers Kathy J.
Published: January 2010

This study examines how the overlap between informal and formal networks in the workplace is related to the degree of attachment for individuals in work organizations. Two types of informal networks, identified by their content and structure, are commonly found in work organizations: Friendship networks and trust networks. Both the content of networks and the coupling (or overlap) of individual member networks with formal authority networks are important for two kinds of attachment, organizational identification and organizational internalization. Data from a survey of employees in five, small, start-up organizations were collected during 1997 and early 1998. Tight coupling between friendship networks and formal authority networks is found to have a strong positive relationship to organizational identification. Tight coupling between trust and formal authority networks is also found to be strongly and positively related to both organizational identification and internalization. Additionally, tight coupling between trust networks and formal authority networks is more influential in predicting identification than coupling between friendship networks and formal authority networks.
Using Affect to Understand Employee Turnover: A Context-Specific Application of a Theory of Social Exchange
Authors: Taylor Catherine , Pillemer Karl
Published: January 2010

Employee turnover is of broad interest, and we focus on turnover in an occupational group that is appropriate for our theoretical approach: Nursing home staff. Using a large and representative sample, we apply conceptual work in the area of social exchange by Lawler and colleagues to examine the role of affect toward the organization on employee turnover as well as antecedents of that affect. We use previous research and survey data to demonstrate that nursing home staff work in the conditions under which Lawler's theories of social exchange apply. We use longitudinal survey data to test whether nursing home staff turnover can be predicted by the level of affective attachment of the individual staff members to the nursing home, controlling for factors related to nursing home turnover. We find that lower nursing home staff turnover at Time 2 is predicted by affective attachment to the nursing home at Time 1.
Criminalizing Spousal Rape: The Diffusion of Legal Reforms
Authors: McMahon-Howard Jennifer , Clay-Warner Jody , Renzulli Linda
Published: January 2010

While efforts to criminalize spousal rape began in the 1970s, by 2002 only twenty-three states had adopted laws that allow for the full prosecution of sexual assault by a spouse. The authors present the first analysis of martial rape law reform to incorporate insights from research on diffusion. The authors find that states are more likely to criminalize spousal rape when women in the state have more economic power. Conversely, states are less likely to criminalize spousal rape when the legislature passed previous incremental reforms or when a neighboring state already criminalized spousal rape. The authors also find that states that criminalize spousal rape under a split-party government are particularly influential in the spread of such reforms and that the processes driving early diffusion are different than the processes driving later diffusion. Overall, results suggest that understanding law reforms requires greater attention to incremental change, negative effects of spatial diffusion, and the importance of time.
The Perils of Assuming a Single Equilibrium
Authors: Whitmeyer Joseph
Published: January 2010

Most techniques sociologists use to analyze empirical phenomena make the single equilibrium assumption that a given configuration of independent variables will produce a single outcome. The author uses two simple models to show that when the assumption does not hold, such techniques may be inadequate. The assumption, moreover, may not be valid for many social phenomena. To show this, the author takes two recent published examples of work that assumes a single equilibrium and presents models of the phenomena that suggest that assumption may not hold. The consequence of analysis that erroneously assumes a single equilibrium may be a fundamental misunderstanding of the phenomenon in question and faulty policy conclusions.
Male sex, single nodularity, and young age are associated with the risk of finding a papillary thyroid cancer on fine-needle aspiration cytology in a large series of patients with nodular thyroid disease
Authors: Rago T , Fiore E , Scutari M , Santini F , Di Coscio G , Romani R , Piaggi P , Ugolini C , Basolo F , Miccoli P , Pinchera A , Vitti P
Published: January 2010

Objective

To evaluate the risk of papillary thyroid carcinoma (PTC) at fine-needle aspiration (FNA) cytology in 34 120 patients.

Results

False positive and false negative rates of FNA cytology were 1.2 and 1.8% in comparison with the histology in 3406 nodules from 3004 patients who underwent surgery. PTC (901 cases) was more frequent in solitary nodule (SN; 446/13 549, 3.3%) than in multinodular goiter (MNG; 411/19 923, 2%,χ2=48.8;P<0.0001), and in males (209/6382, 3.3%) than in females (648/26 945, 2.40%,χ2=15.58;P<0.0001). PTC prevalence in Graves' disease (GD; 13/286, 4.5%) and Hashimoto's thyroiditis (HT; 31/508, 6.1%) was higher than in SN, this difference being significant in HT (χ2=8.7;P=0.003), but not in GD (χ2=1.6;P=0.2).

Using the multiple logistic regression analysis, independent risk predictors of PTC were determined, which were younger age (odds ratio (OR)=0.97, confidence interval (CI) 0.964–0.974;P<0.0001), male gender (OR=1.44, CI 1.231–1.683;P<0.0001), and SN versus MNG (OR=0.63, CI 0.547–0.717;P<0.0001). The individual risk predictivity was highly improved by including serum TSH in the prediction model, which was measured at FNA in 11 919 patients.

Conclusion

A cytology suspicious or indicative of PTC was associated with younger age, male gender, and solitary versus multiple nodularity. These clinical parameters, together with serum TSH, may allow formulation of an algorithm that could be usefully applied to predict the risk of PTC in individual patients when cytology does not give a diagnostic result.
Endogenous folates and single-carbon metabolism in the ovarian follicle, oocyte and pre-implantation embryo
Authors: Kwong W Y , Adamiak S J , Gwynn A , Singh R , Sinclair K D
Published: January 2010

Maternal B-vitamin status at conception can affect fertility and the health of offspring. This study details transcript expression for genes encoding key enzymes in the linked methionine/folate cycles in the bovine oocyte, somatic cells of the ovarian follicle and pre-implantation embryo. Transcripts for all 12 enzymes that were studied and for the two folate receptors (FOLR1andFOLR2) and reduced folate carrier (SLC19A1) were expressed in liver cells, but transcripts for betaine-homocysteine methyltransferase and methionine adenosyl transferase 1A were absent in all ovarian cells, and transcripts forFOLR2were absent in embryonic cells. Transcripts for glycine methyltransferase were also absent/weak in cumulus and granulosa cells. The absence of these enzymes could have a profound effect on single-carbon metabolism within the ovary and pre-implantation embryo. Immunocytochemical analysis revealed SLC19A1 protein expression on the plasma and basal-lateral membranes of the pre-implantation embryo. The folate antagonist methotrexate (MTX) enters the cell via SLC19A1, and in the current study, MTX inclusion in bovine/ovine culture media at either 1 or 10 μM from the 1-cell stage inhibited embryo development beyond the 8-cell stage. Hypoxanthine and thymidine (100 μM) increased the proportion of embryos that developed to blastocysts, but the cell number was reduced by 20%. The reduced uptake of [35S] methionine into intra-cellularS-adenosylmethionine andS-adenosylhomocysteine pools, together with reduced uptake of glutamate and tryptophan, was consistent with depleted intra-cellular pools of reduced folates. These data provide an insight into the importance of maternal dietary folate/B-vitamin status during the peri-conceptional period.
Adoption of Body Mass Index Guidelines for Screening and Counseling In Pediatric Practice
Authors: Klein Jonathan D. , Sesselberg Tracy S. , Johnson Mark S. , O'Connor Karen G. , Cook Stephen , Coon Marian , Homer Charles , Krebs Nancy , Washington Reginald
Published: January 2010

OBJECTIVE:

The purpose of this study was to examine pediatrician implementation of BMI and provider interventions for childhood overweight prevention and treatment.

METHODS:

Data were obtained from the American Academy of Pediatrics (AAP) Periodic Survey of Fellows No. 65, a nationally representative survey of AAP members. Surveys that addressed the provision of screening and management of childhood overweight and obesity in primary care settings were mailed to 1622 nonretired US AAP members in 2006.

RESULTS:

One thousand five (62%) surveys were returned; 677 primary care clinicians in active practice were eligible for the survey. Nearly all respondents (99%) reported measuring height and weight at well visits, and 97% visually assess children for overweight at most or every well-child visit. Half of the respondents (52%) assess BMI percentile for children older than 2 years. Most pediatricians reported that they do not have time to counsel on overweight and obesity, that counseling has poor results, and that having simple diet and exercise recommendations would be helpful in their practice. Pediatricians in large practices and those who had attended continuing medical education on obesity were more familiar with national expert guidelines, were more likely to use BMI percentile, and had higher self-efficacy in practices related to childhood and adolescent overweight and obesity. Multivariate analysis revealed that pediatricians with better access to community and adjunct resources were more likely to use BMI percentile.

CONCLUSIONS:

BMI-percentile screening in primary pediatric practice is underused. Most pediatricians believe that they can and should try to prevent overweight and obesity, yet few believe there are good treatments once a child is obese. Training, time, and resource limitations affect BMI-percentile use. Awareness of national guidelines may improve rates of BMI-percentile use and recognition of opportunities to prevent childhood and adolescent obesity.
Male Gender Is Associated With Intraventricular Hemorrhage
Authors: Mohamed Mohamed A. , Aly Hany
Published: January 2010

OBJECTIVE:

The goal was to examine the association of gender with intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL) in a large national database.

METHODS:

The National Inpatient Sample database was analyzed for the years 1998, 1999, 2001, 2002, and 2004 and its pediatrics version for the years 1997, 2000, and 2003. The National Inpatient Sample and its pediatrics version are annually collected databases for inpatient admissions from >1000 hospitals across the United States. We included all very low birth weight (VLBW) infants (birth weight [BW] of <1500 g) and excluded infants with major congenital anomalies. VLBW infants with IVH or PVL were identified by using International Classification of Diseases, Ninth Revision, diagnostic codes. We analyzed the data by using χ2 and Fisher's exact tests to calculate odds ratios (ORs) and logistic regression analysis to control for possible confounders.

RESULTS:

The data included 104 847 VLBW infants. With controlling for significant confounders, IVH was associated with male gender (15.9% vs 13.6%; adjusted OR [AOR]: 1.15 [95% confidence interval: 1.11–1.19]; P < .001). More boys than girls had severe IVH (38% vs 32.7%; AOR: 1.18 [95% confidence interval: 1.06–1.32]; P < .004). The increased rates of IVH and severe IVH in boys were significant in the BW subgroups of <1000 g and 1000 to 1499 g. The association of male gender with IVH and severe IVH was more significant in infants of 1000 to 1499 g (AOR: 1.19 vs 1.14; P = .006). The incidence of PVL in VLBW infants was 0.41%, and rates did not differ between genders (0.38% vs 0.43%; P = .42).

CONCLUSIONS:

Compared with girls, VLBW male newborns are at greater risk to develop IVH and severe IVH but not PVL. The association of male gender with IVH or severe IVH is stronger with higher BWs.
Health-Related Quality of Life of Children With Mild to Moderate Chronic Kidney Disease
Authors: Gerson Arlene C. , Wentz Alicia , Abraham Allison G. , Mendley Susan R. , Hooper Stephen R. , Butler Robert W. , Gipson Debbie S. , Lande Marc B. , Shinnar Shlomo , Moxey-Mims Marva M. , Warady Bradley A. , Furth Susan L.
Published: January 2010

OBJECTIVE:

To compare the health-related quality of life (HRQoL) of children with chronic kidney disease (CKD) with healthy children; to evaluate the association between CKD severity and HRQoL; and to identity demographic, socioeconomic, and health-status variables that are associated with impairment in HRQoL in children with mild to moderate CKD.

METHODS:

This was a cross-sectional assessment of HRQoL in children who were aged 2 to 16 and had mild to moderate CKD using the Pediatric Inventory of Quality of Life Core Scales (PedsQL). Overall HRQoL and PedsQL domain means for parents and youth were compared with previously published norms by using independent sample t tests. Study participants were categorized by kidney disease stage (measured by iohexol-based glomerular filtration rate [iGFR]), and group differences in HRQoL were evaluated by using analysis of variance and Cuzick trend tests. The association between hypothesized predictors of HRQoL and PedsQL scores was evaluated with linear and logistic regression analyses.

RESULTS:

The study sample comprised 402 participants (mean age: 11 years, 60% male, 70% white, median iGFR: 42.5 mL/min per 1.73 m2, median CKD duration: 7 years). Youth with CKD had significantly lower physical, school, emotional, and social domain scores than healthy youth. iGFR was not associated with HRQoL. Longer disease duration and older age were associated with higher PedsQL scores in the domains of physical, emotional, and social functioning. Older age was associated with lower school domain scores. Maternal education ≥16 years was associated with higher PedsQL scores in the domains of physical, school, and social functioning. Short stature was associated with lower scores in the physical functioning domain.

CONCLUSIONS:

Children with mild to moderate CKD, in comparison with healthy children, reported poorer overall HRQoL and poorer physical, school, emotional, and social functioning. Early intervention to improve linear growth and to address school functioning difficulties is recommended.
Cerebral Magnetic Resonance Biomarkers in Neonatal Encephalopathy: A Meta-analysis
Authors: Thayyil Sudhin , Chandrasekaran Manigandan , Taylor Andrew , Bainbridge Alan , Cady Ernest B. , Chong W. K. Kling , Murad Shahed , Omar Rumana Z. , Robertson Nicola J.
Published: January 2010

OBJECTIVE:

Accurate prediction of neurodevelopmental outcome in neonatal encephalopathy (NE) is important for clinical management and to evaluate neuroprotective therapies. We undertook a meta-analysis of the prognostic accuracy of cerebral magnetic resonance (MR) biomarkers in infants with neonatal encephalopathy.

METHODS:

We reviewed all studies that compared an MR biomarker performed during the neonatal period with neurodevelopmental outcome at ≥1 year. We followed standard methods recommended by the Cochrane Diagnostic Accuracy Method group and used a random-effects model for meta-analysis. Summary receiver operating characteristic curves and forest plots of each MR biomarker were calculated. χ2 tests examined heterogeneity.

RESULTS:

Thirty-two studies (860 infants with NE) were included in the meta-analysis. For predicting adverse outcome, conventional MRI during the neonatal period (days 1–30) had a pooled sensitivity of 91% (95% confidence interval [CI]: 87%–94%) and specificity of 51% (95% CI: 45%–58%). Late MRI (days 8–30) had higher sensitivity but lower specificity than early MRI (days 1–7). Proton MR spectroscopy deep gray matter lactate/N-acetyl aspartate (Lac/NAA) peak-area ratio (days 1–30) had 82% overall pooled sensitivity (95% CI: 74%–89%) and 95% specificity (95% CI: 88%–99%). On common study analysis, Lac/NAA had better diagnostic accuracy than conventional MRI performed at any time during neonatal period. The discriminatory powers of the posterior limb of internal capsule sign and brain-water apparent diffusion coefficient were poor.

CONCLUSIONS:

Deep gray matter Lac/NAA is the most accurate quantitative MR biomarker within the neonatal period for prediction of neurodevelopmental outcome after NE. Lac/NAA may be useful in early clinical management decisions and counseling parents and as a surrogate end point in clinical trials that evaluate novel neuroprotective therapies.
Predicting Low Dose Effects for Chemicals in High Through-Put Studies
Authors: Stanek Edward J. , Calabrese Edward J.
Published: January 2010

High through-put studies commonly use automated systems with 96-well plates in which multiple chemicals are tested at multiple doses using log-2 dose increments after a suitable incubation period. There are typically multiple (ranging from five to eleven) doses on each chemical, and occasionally plate replications of the dose-response studies. The target endpoint for such studies is typically the LC50, but for some chemicals, there may be multiple doses below a benchmark dose where there is no apparent adverse response relative to control response. We show how an estimation approach can lead to clearly interpretable results about response in the low dose region using data from a high throughput study of 2189 chemicals on yeast. Accurate estimates can be obtained of response for study chemicals by using best linear unbiased predictors (BLUPs) in a mixed model, and summarized via plots with expected response (assuming no low-dose effect) with confidence intervals for response below the benchmark dose for each chemical, providing an informative summary of response at low doses. We conclude that this approach can provide valuable insights that would be missed if the observational data were only considered through the lens of statistical methods appropriate for experimental studies.
Clinical Performance of Vital Bleaching Techniques
Authors: Bernardon J. K. , Sartori N. , Ballarin A. , Perdigão J. , Lopes G. , Baratieri L. N.
Published: January 2010

Clinical Relevance

Tooth bleaching results obtained with different techniques (home bleaching, in-office bleaching with or without light source and a combination of in-office bleaching + home bleaching) were similar after a two-week period. Dentists must inform their patients about the expected outcomes of each procedure and provide an evidence-based choice.
Evaluation of Proximal Contact Tightness of Class II Resin Composite Restorations
Authors: Saber M. H. , Loomans A. C. , Zohairy A. El , Dörfer C. E. , El-Badrawy W.
Published: January 2010

Clinical Relevance

The use of sectional matrix bands combined with a separation ring and wedge is recommended to reconstruct the proximal contact area of Class II resin composite restorations
Influence of Adhesive Application Time on Enamel Bond Strength of Single-step Self-etch Adhesive Systems
Authors: Tsuchiya H. , Tsubota K. , Iwasa M. , Ando S. , Miyazaki M. , Platt J. A.
Published: January 2010

Clinical Relevance

Proper application duration of single-step self-etch adhesive plays an important role in obtaining optimal enamel bond strength.
Chromatic Influence of Value Resin Composites
Authors: Schmeling M. , Meyer-Filho A. , Andrada M. A. C. , Baratieri L. N.
Published: January 2010

Clinical Relevance

Value resin composites used to replace enamel can induce a brightness decrease in stratified composite restoration techniques.
Early life relict feature in peptide mass distribution
Authors: Zubarev Roman , Artemenko Konstantin , Zubarev Alexander , Mayrhofer Corina , Yang Hongqian , Fung Y.
Published: January 2010

The molecular mass of a biomolecule is characterized by the monoisitopic mass Mmono and the average isotopic mass Mav. We found that tryptic peptide masses mapped on a plane made by two parameters derived from Mmono and Mav form a peculiar feature in the form of a ‘band gap’ stretching across the whole ‘peptide galaxy’, with a narrow line in the centre. The purpose of this study was to investigate possible reasons for the emergence of such a feature, provided it is not a random occurrence. The a priori probability of such a feature to emerge by chance was found to be less than 1:100. Peptides contributing to the central line have elemental compositions following the rules S = 0; Z = C - (N + H)/2 = 0, which nine out of 20 amino acid residues satisfy. The relative abundances of amino acids in the peptides contributing to the central line correlate with the consensus order of emergence of these amino acids, with ancient amino acids being overrepresented in on-Line peptides. Since linear correlation between Mav and Mmono reduces the complexity of polypeptide molecules, and the turnover rate of less complex molecules should be faster in non-equilibrium abiotic synthesis, we hypothesize that the line could be a signature of abiotic production of primordial biopolymers. The linear dependence between the average isotopic masses and monoisotopic masses may have influenced the selection of amino acid residues for terrestrial life.
The Monitoring of the Bearing Nodes with Excessive Radial Clearances Using the FAM-C and FDM-A Methods
Authors: Gębura Andrzej , Tokarski Tomasz
Published: January 2010

The Monitoring of the Bearing Nodes with Excessive Radial Clearances Using the FAM-C and FDM-A Methods

The paper has been intended to present findings resulting from the monitoring of the bearing support elements with increased radial clearances with the FAM-C1 and FDM-A2 methods. The role the lubricant film plays in this type of the rolling-elements' wear has been described. Discussed are symptoms, parameters, and hazards to the resonant state in bearing nodes, as well as capabilities of diagnosing them with the FAM-C and FDM-A methods. Hypotheses about subsequent stages of the wearing process in aircraft turbojet engine's bearing support assemblies, including how the resonant state occurs, have been presented. The mechanism of the resonance in rolling-element bearings has been described, with particular attention paid to the effects of gyrostatic moments upon the bearing support elements, both in micro- and macro-scale. Theoretical analyses have been supplemented with findings resulting from the diagnostic work carried out by the Authors, and with data from the mechanical verification of engines in the course of the authorised dismantling thereof.
Metoda Korekcji Błędów skrośnych DLA Pomiarów Parametrów Ruchu w Zintegrowanych Systemach Awionicznych
Authors: Szelmanowski Andrzej
Published: January 2010

Metoda Korekcji Błędów skrośnych DLA Pomiarów Parametrów Ruchu w Zintegrowanych Systemach Awionicznych

W artykule przedstawiono wyniki przeprowadzonych w Instytucie Technicznym Wojsk Lotniczych (ITWL) analiz wpływu oddziaływań skrośnych na błędy pomiaru parametrów ruchu statku powietrznego przez klasyczne (elektromechaniczne) czujniki prędkości kątowej i przyspieszeniomierze liniowe. Podano zależności i przebiegi ruchu stożkowego, wytwarzanego na modelu stanowiska SRS-1 zbudowanego w ITWL. Dla posiadanych czujników prędkości kątowej I-1426 (firmy SFIM) i czujników przyspieszeń liniowych MP-95 (ZSRR) przedstawiono modele błędów skrośnych oraz podano metody ich korekcji na podstawie sygnałów z tych czujników. Dla ruchu stożkowego zobrazowano pomiary błędów skrośnych i efektywność ich korekcji przy zastosowaniu algorytmów opracowanych w ITWL.
Duty cycle tolerant binary gratings for fabricable short period phase masks
Authors: Gamet E. , Pigeon F. , Parriaux O.
Published: January 2010

Wavelength scale 1D binary gratings of rectangular corrugation profile are often used as diffractive elements acting on incident free space waves under different incidence angle, wavelength and polarization. Their optical function is best understood by considering the interplay of the grating modes propagating up and down the periodic walls and slits of the segmented structure. The interference conditions between modes depend on the difference between the effective index of the interfering modes and on their relative amplitude. This difference and relative amplitude depend critically on the ratio between the wall and slit widths which is difficult to control technologically. The condition for a wide tolerance of the effective index difference and for a balanced mode excitation on the wall/slit ratio is found analytically and once for all for a wide class of 1D gratings. It is also found that TE interference elements may exhibit a very wide wall/slit ratio tolerance domain.
Common Sand Boa: A Vivid Herpets of Nepal
Authors: Chaudhary RD
Published: January 2010

DOI: 10.3126/init.v2i1.2516 The Initiation Vol.2(1) 2008 pp33
Payments for Environmental Services: A New People Centric Approach for Biodiversity Conservation in Nepal
Authors: Chalise Lina
Published: January 2010

Payment for Environmental Services (PES) in its preliminary stage is gaining much attention. The worth of many valuable environmental services is undermined from centuries due its free access. But now with the advancing time the blind conservation practices seem to be unreal. Thus, PES mechanism provides an attractive and convincing package in conservation and valuation of most of the indirect services of environment. This is a review article based on the introductory queries on emerging issue of valuation of environmental services via PES mechanism. Key Words: Environmental services, Global biodiversity, Conservation practices DOI: 10.3126/init.v2i1.2529 The Initiation Vol.2(1) 2008 pp99-103