bluuebunny/crossref_metadata_2025 huggingface dataset:
Minimally invasive transfrontal sinus approach to resection of large tumors of the subfrontal skull base
Authors: Ducic Yadranko , Coimbra Caetano
Published: October 2011

Objectives/Hypothesis:

To review our favorable experience with a minimally invasive transfrontal sinus approach to tumors of the subfrontal region.

Study Design:

Retrospective review in a tertiary care referral practice.

Methods:

Patients undergoing anterior skull base surgery by the senior author (Y.D.) were reviewed and transfrontal sinus approach patients selected for review. All cases of transfrontal sinus approaches to the base of the anterior cranial fossa from 2007 to 2011 were reviewed in a retrospective fashion.

Results:

A total of 14 cases were noted. Male to female ratio was 10 to 4 with an average age of 58.2 years. The pathologies included: meningioma (n = 6), esthesioneuroblastoma (n = 3), squamous cell carcinoma (n = 3), adenocarcinoma (n = 1), and adenoid cystic carcinoma (n = 1). Five intradural and nine extradural dissections were performed. No major complications were noted, and no patients required conversion to a traditional transfacial approach or required the use of a craniotomy. Twelve patients underwent complete tumor removal, whereas two patients underwent subtotal tumor removal. Reasons for subtotal removal were not access related but rather tumor characteristic related (carotid artery wall involvement, optic chiasm involvement). Contraindication to this approach is the presence of a hypoplastic or aplastic frontal sinus.

Conclusions:

The minimally invasive transfrontal sinus approach to the subfrontal region provides ready expeditious access to the base of the anterior cranial fossa without the need for brain retraction, craniotomy or naso‐orbital osteotomies. It represents an excellent alternative in the surgical access of both intra‐ and extradural tumors in this region of the skull base. Laryngoscope, 121:2290–2294, 2011
Reconstruction of complex peripheral facial nerve defects by a combined approach using facial nerve interpositional graft and hypoglossal‐facial jump nerve suture
Authors: Volk Gerd Fabian , Pantel Mira , Streppel Michael , Guntinas‐Lichius Orlando
Published: October 2011

Objectives/Hypothesis:

To describe a modified facial nerve reconstruction technique for complex defects of the facial fan after parotid surgery that avoids synkinesis between upper and lower face.

Study Design:

Retrospective case series.

Methods:

Patients who had undergone radical parotidectomy with a large defect of the facial fan, reconstruction of the upper face by facial nerve interpositional graft, and reconstruction of the lower face by hypoglossal‐facial nerve jump nerve suture were included in this series.

Results:

Four patients underwent the modified combined approach after tumor resection and prior to postoperative radiotherapy in three of the four cases. Surgery was combined with an upper lid weight implantation. Regeneration of the face was successful in all cases within 12 to 16 months. Most important, the separated reanimation of the upper and lower face circumvented synkinesis of the upper and lower face. This factor was essential for good functional results. Using the hypoglossal jump technique instead of a classical cross‐nerve suture technique prevented the sacrifice of ipsilateral tongue function.

Conclusions:

The presented method offers satisfactory results for facial reanimation and avoids synkinesis between the upper and lower face. Using the jump technique instead of a classic hypoglossal transfer as it was described originally for the combined approach avoids long‐term sequelae for the tongue. Laryngoscope, 121:2402–2405, 2011
Fabrication of Substrates with Defined Mechanical Properties and Topographical Features for the Study of Cell Migration
Authors: Charest Jonathan M. , Califano Joseph P. , Carey Shawn P. , Reinhart‐King Cynthia A.
Published: October 2011

Both substrate topography and substrate mechanical properties are known to influence cell behavior, but little is known about how they act in concert. Here, a method is presented to introduce topographical features into PA hydrogel substrates that span a wide range of physiological E values. Gel swelling plays a significant role in the fidelity of protruding micromolded features, with the most efficient pattern transfer occurring at a crosslinking concentration equal to or greater than ≈5%. In contrast, swelling does not influence the spacing fidelity of microcontact printed islands of collagen on 2D PA substrates. BAECs cultured on micromolded PA substrates exhibit contact guidance along ridges patterned for all E tested.

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Projected numbers of people with movement disorders in the years 2030 and 2050
Authors: Bach Jan‐Philipp , Ziegler Uta , Deuschl Günther , Dodel Richard , Doblhammer‐Reiter Gabriele
Published: October 2011

Background:

Movement disorders are chronic diseases with an increasing prevalence in old age. Because these disorders pose a major challenge to patients, families, and health care systems, there is a need for reliable data about the future number of affected people.

Patients and Methods:

We searched the literature to identify epidemiological studies to obtain age‐specific prevalence data of movement disorders. We combined the age‐specific prevalence data with population projections for Europe, the United States, and Canada.

Results:

Movement disorders will increase considerably between 2010 and 2050. The highest increase will be for dementia with Lewy bodies. In several countries, we project a near doubling of patients with PD.

Conclusions:

There will be a strong increase in the number of people affected by most movement disorders between 2010 and 2050. This increase will mostly depend on the future aging of populations in terms of their age structure and future life expectancy. © 2011 Movement Disorder Society
Freezing in Parkinson's disease: A spatiotemporal motor disorder beyond gait
Authors: Vercruysse Sarah , Spildooren Joke , Heremans Elke , Vandenbossche Jochen , Levin Oron , Wenderoth Nicole , Swinnen Stephan P. , Janssens Luc , Vandenberghe Wim , Nieuwboer Alice
Published: October 2011

Freezing of gait (FOG) is an incapacitating problem in Parkinson's disease that is difficult to manage therapeutically. We tested the hypothesis that impaired rhythm and amplitude control is a common mechanism of freezing which is also present during other rhythmic tasks. Therefore, we compared the occurrence and spatiotemporal profiles of freezing episodes during upper limb motion, lower limb motion, and FOG. Eleven freezers, 12 non‐freezers, and 11 controls performed a rhythmic bilateral finger movement task. The triggering effect of movement speed, amplitude, and coordination pattern was evaluated. Regression slopes and spectral analysis addressed the spatial and temporal kinematic changes inherent to freezing episodes. The FOG Questionnaire score significantly predicted severity of upper limb freezing, present in 9 freezers, and of foot freezing, present in 8 freezers. Similar to gait, small‐amplitude movements tended to trigger upper limb freezing, which was preceded by hastened movement and a strong amplitude breakdown. Upper limb freezing power spectra were broadband, including increased energy in the “freeze band” (3–8 Hz). Contrary to FOG, unilateral upper limb freezing was common and occurred mainly on the disease‐dominant side. The findings emphasize that a core motor problem underlies freezing which can affect various movement effectors. This deficit may originate on the disease‐dominant body side and interfere with amplitude and timing regulation during repetitive limb movements. These results may shift current thinking on the origins of freezing as being not exclusively a gait failure. © 2011 Movement Disorder Society
Coaxial waveguide MRI
Authors: Alt Stefan , Müller Marco , Umathum Reiner , Bolz Armin , Bachert Peter , Semmler Wolfhard , Bock Michael
Published: October 2011

As ultrahigh‐field MR imaging systems suffer from the standing wave problems of conventional coil designs, the use of antenna systems that generate travelling waves was suggested. As a modification to the original approach, we propose the use of a coaxial waveguide configuration with interrupted inner conductor. This concept can focus the radiofrequency energy to the desired imaging region in the human body and can operate at different Larmor frequencies without hardware modifications, as it is not limited by a lower cut‐off frequency. We assessed the potential of the method with a hardware prototype setup that was loaded with a tissue equivalent phantom and operated with imaging areas of different size. Signal and flip angle distributions within the phantom were analyzed, and imaging at different Larmor frequencies was performed. Results were compared to a finite difference time domain simulation of the setup that additionally provides information on the spatial distribution of the specific absorption rate load. Furthermore, simulation results with a human model (virtual family) are presented. It was found that the proposed method can be used for MRI at multiple frequencies, achieving transmission efficiencies similar to other travelling wave approaches but still suffers from several limitations due to the used mode of wave propagation. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
The importance of axonal undulation in diffusion MR measurements: a Monte Carlo simulation study
Authors: Nilsson Markus , Lätt Jimmy , Ståhlberg Freddy , van Westen Danielle , Hagslätt Håkan
Published: October 2011

Many axons follow wave‐like undulating courses. This is a general feature of extracranial nerve segments, but is also found in some intracranial nervous tissue. The importance of axonal undulation has previously been considered, for example, in the context of biomechanics, where it has been shown that posture affects undulation properties. However, the importance of axonal undulation in the context of diffusion MR measurements has not been investigated. Using an analytical model and Monte Carlo simulations of water diffusion, this study compared undulating and straight axons in terms of diffusion propagators, diffusion‐weighted signal intensities and parameters derived from diffusion tensor imaging, such as the mean diffusivity (MD), the eigenvalues and the fractional anisotropy (FA). All parameters were strongly affected by the presence of undulation. The diffusivity perpendicular to the undulating axons increased with the undulation amplitude, thus resembling that of straight axons with larger diameters. Consequently, models assuming straight axons for the estimation of the axon diameter from diffusion MR measurements might overestimate the diameter if undulation is present. FA decreased from approximately 0.7 to 0.5 when axonal undulation was introduced into the simulation model structure. Our results indicate that axonal undulation may play a role in diffusion measurements when investigating, for example, the optic and sciatic nerves and the spinal cord. The simulations also demonstrate that the stretching or compression of neuronal tissue comprising undulating axons alters the observed water diffusivity, suggesting that posture may be of importance for the outcome of diffusion MRI measurements. Copyright © 2011 John Wiley & Sons, Ltd.
Evidence for the presence of high risk human papillomavirus in retinoblastoma tissue from nonfamilial retinoblastoma in developing countries
Authors: Shetty Omshree A. , Naresh Kikkeri N. , Banavali Shripad D. , Shet Tanuja , Joshi Rupali , Qureshi Sajid , Mulherkar Rita , Borges Anita , Desai Sangeeta B.
Published: October 2011

Background

The prevalence of human papillomavirus (HPV) infection in India is high. HPV infection is known to cause cervical cancer and has also been implicated in the pathogenesis of retinoblastoma (RB), a common intraocular malignant tumor of childhood which can be familial or sporadic. Despite the high incidence of RB in India, its familial form is rare. Hence this study was undertaken to investigate whether high‐risk HPV types 16 and 18 are involved in the development of RB.

Methods

Formalin fixed paraffin embedded RB tissues (n = 76) including prospective cases with corresponding maternal cervical smears (n = 10) were analyzed for the presence of HPV DNA sequences. Expression of the cell cycle regulatory proteins viz; p105, p107, p30, p16, E2F‐1, E2F‐4, and MiB‐1 was studied by immunohistochemistry (IHC) (n = 34).

Results

A total of 53 out of 76 (69.7%) cases were positive for HPV, of these 3 cases were positive for HPV‐16, 23 for HPV‐18, and 27 for both HPV‐16 and ‐18. Of the prospective cases (n = 10) studied, five cases along with the corresponding maternal cervical cytology smear had identical HPV status. HPV‐16 positive tumors were classified as well differentiated (P = 0.013). Nuclear expression of pRB2/p130 showed significant association with HPV‐16 infection (P = 0.04) or dual infection of HPV‐16/‐18 (P = 0.02).

Conclusions

Our study lends support to the hypothesis that infection of HPV‐16/‐18 may play an important role in the development of nonfamilial form of RB in children in India. Pediatr Blood Cancer 2012; 58: 185–190. © 2011 Wiley Periodicals, Inc.
Gonadal function and parenthood 20 years after treatment for childhood lymphoma: A cross‐sectional study
Authors: Hamre Hanne , Kiserud Cecilie E. , Ruud Ellen , Thorsby Per M. , Fosså Sophie D.
Published: October 2011

Background

Gonadal function decades after treatment for childhood lymphoma (CL) is not well described. This cross‐sectional study had two aims: (1) describe long‐term gonadal function and fertility in childhood lymphoma survivors (CLSs), and (2) explore anti‐Mullerian hormone (AMH) as a measure of ovarian function in CLSs.

Procedure

Seventy‐four male and 62 female CLSs participated in a survey consisting of a questionnaire, clinical examination, and blood/semen analysis. Prior treatment was categorized according to gonadotoxicity. Hypogonadism was determined by levels of gonadal hormones based on luteinizing hormone, follicle‐stimulating hormone, testosterone (males), AMH (females <40 years), and menstrual status. Fertility was explored according to pregnancies achieved, semen analysis, and AMH.

Results

Hypogonadism was observed in 7 of 66 males (11%). Seven of 64 males (11%) were categorized as infertile. Nine of 45 females <40 years (20%) were at risk to develop premature ovarian failure (POF). Twenty of 45 females (44%) showed low‐AMH levels indicating decreased fertility. Four “critically low” females reported pregnancies within the preceding 2 years. Sixty‐four percent of the males and 93% of the females attempting parenthood had been successful (P = 0.01). Hypogonadism and low‐AMH were related to treatment burden.

Conclusion

Twenty years after treatment of CL, female CLSs' attempts of pregnancy initiation are mostly successful, while males seem at higher risk of infertility. Hypogonadism is a problem in 10% of the male CLSs. Based on AMH levels, POF is a risk in 20% of the female CLSs. The clinical significance of AMH reflecting true probability of fertility needs further research in cancer survivors. Pediatr Blood Cancer 2012;59:271–277. © 2011 Wiley Periodicals, Inc.
Early metabolic improvement following bariatric surgery in morbidly obese adolescents
Authors: Teeple E.A. , Teich S. , Schuster D.P. , Michalsky M.P.
Published: October 2011

Bariatric surgery results in durable weight loss and improved comorbidities. The objectives of this study were to examine the efficacy of gastric bypass in reducing comorbid burden and improving metabolic status among morbidly obese adolescents. The medical records of 15 gastric bypass patients were retrospectively reviewed. Changes in metabolic markers were determined at baseline, 1 and 2 years post‐operatively. Comparative analysis demonstrated significant improvement in weight, BMI, insulin, HbA1C, C‐peptide, %B, %S, IR, cholesterol, percentile cholesterol, TG, percentile TG, HDL, percentile HDL, LDL, percentile LDL, and VLDL. Results support bariatric surgery as a treatment for morbidly obese adolescents with comorbidities. Pediatr Blood Cancer 2012; 58: 112–116. © 2011 Wiley Periodicals, Inc.
Energy balance: An overview with emphasis on children
Authors: Tam Charmaine S. , Ravussin Eric
Published: October 2011

Childhood obesity is a significant public health problem, affecting one in five children in the United States. At the crux of this issue is a dysregulation of energy intake and energy expenditure. This review will provide an overview on energy and nutrient balance. We discuss energy balance studies in children using indirect and direct measures, and focus particularly on obesity as a deleterious consequence in childhood survivors of cancer. Obesity affects 11–57% of children with acute lymphoblastic leukemia, probably due to increased energy intake and reduced energy expenditure secondary to reduced habitual activity caused by fatigue. However, most of the studies in children with leukemia are retrospective, use BMI as a measure of obesity, and are inconclusive about the impact of the type of treatment on the development of obesity later in life. To better understand the etiology of obesity in both healthy and sick children, we need to undertake nutrient balance studies with appropriate measures of fat mass and fat distribution while keeping in mind the influence of normal tissue growth and puberty on energy balance. Pediatr Blood Cancer 2012; 58: 154–158. © 2011 Wiley Periodicals, Inc.
On the reported experimental evidence for the quasi‐Fermi level split in quantum‐dot intermediate‐band solar cells
Authors: Abouelsaood Ahmed A. , Ghannam Moustafa Y. , Poortmans Jef
Published: October 2011

The reported experimental evidence for the quasi‐Fermi level split in quantum‐dot intermediate‐band solar cells is carefully examined. It is shown that the separation of the quasi‐Fermi level of the intermediate band from that of the conduction band is not consistent with the experimental results of the quantum efficiency and the luminescence intensity of the InAs/GaAs cells. The fact that the electroluminescence spectrum is too wide, extending much further than we expect on the basis of the measured quantum efficiency in the direction of increasing photon energies, indicates that the temperature of the optically active regions of the cell during the electroluminescence measurements is considerably higher than room temperature. The best agreement with the experimental results is achieved with a temperature of about 525 K. This temperature rise is probably a result of the heating effect of the relatively high forward current used in the luminescence experiments. It is argued that the lack of a quasi‐Fermi level split in this case is associated with the absence of a gap in the emission/absorption spectrum of sub‐bandgap photons. Copyright © 2011 John Wiley & Sons, Ltd.
Mothers and fathers of children with cancer: loss of control during treatment and posttraumatic stress at later follow‐up
Authors: Norberg Annika Lindahl , Boman Krister K.
Published: October 2011

Background

A child's cancer can lead to changes in parental role functioning, including loss of control. We studied the extent to which parental perceived loss of control during a child's cancer treatment predicted posttraumatic stress symptoms (PTSS) after completion of treatment.

Method and participants

The sample of this longitudinal study included 62 parents (36 mothers and 26 fathers) of children currently in treatment for malignant disease (T1) and after completion of treatment (T2). Loss of control was assessed at T1 using a self‐report measure, that is the loss of control module of the Parental Psychosocial Distress‐Cancer questionnaire. PTSS were assessed at T2 using the Impact of Event Scale‐Revised. Main analyses were carried out for mothers and fathers separately.

Results

The majority of the parents, 55% (n = 34), reported loss of control on more than half of the assessed domains. Only 5% (n = 3) reported no loss of control whatsoever. At T2, some degree of PTSS was reported by 89% (n = 55). These outcomes were similar for mothers and fathers. Loss of control at T1 predicted stronger PTSS at T2 primarily among mothers.

Conclusion

The experience of loss of control during cancer treatment is a salient risk factor for later PTSS in mothers. The situational threat to the regular parental role is discussed as an explanation to this observation. Interventions should address informational needs, parent participation in care, and professional support to maintain a sense of control and functioning in their parental role. Copyright © 2011 John Wiley & Sons, Ltd.
Influence of implantation conditions of He+ ions on the structure of a damaged layer in GaAs(001)
Authors: Shcherbachev Kirill , Bailey Melanie J.
Published: October 2011

An investigation into the influence of implantation conditions (dose, energy, and target temperature) of He+ ions on the damage structure of GaAs (100) substrates was performed by HRXRD, scanning electron microscopy, and Nomarski microscopy. Blistering is shown to become apparent as characteristic features of isolines in RSMs. We propose that the formation of the defects yielding a characteristic XRDS is defined by the behavior of implanted atoms in the GaAs matrix, depending on two competing processes: (1) formation of the gas‐filled bubbles; (2) diffusion of the He atoms from the bubbles toward the surface and deep into the GaAs substrate. We conclude that the gas‐filled bubbles change the structure of the irradiated layer, resulting in the formation of strained crystalline areas of the GaAs matrix.
Silymarin Inhibits Cervical Cancer Cell Through an Increase of Phosphatase and Tensin Homolog
Authors: Yu Hann‐Chin , Chen Li‐Jen , Cheng Kai‐Chun , Li Ying‐Xiao , Yeh Ching‐Hua , Cheng Juei‐Tang
Published: October 2011

Silymarin is an active constituent contained in the seeds of the milk thistle plant and is widely used as a hepatic protection agent due to its antioxidant‐like activity. In the present study we evaluated the potential action of silymarin against cervical cancer and investigated its mechanism of action. Treatment of cervical cancer cells (C‐33A) with silymarin resulted in a significant decrease in cell viability. Silymarin induced apoptosis through the modulation of Bcl‐2 family proteins and activation of caspase 3. Silymarin also inhibited the phosphorylation of Akt with an increase in expression of phosphatase and tensin homolog (PTEN). We also observed that silymarin suppressed C‐33A cell invasion and wound‐healing migration in a concentration‐dependent manner. Western‐blot analysis showed that silymarin significantly inhibited the expression of matrix metalloproteinase‐9 (MMP‐9) in C‐33A cells. Furthermore, we applied siRNA to lower the PTEN gene, which diminished the anticancer actions of silymarin. Taken together, these results show that silymarin has the potential to suppress the survival, migration and invasion of C‐33A cancer cells; thus, it could be developed as a promising agent for the treatment of cervical cancer in the future. Copyright © 2011 John Wiley & Sons, Ltd.
Dropping Damage Boundary Curves for Cubic and Hyperbolic Tangent Packaging Systems Based on Key Component
Authors: Jiang Jiu‐Hong , Wang Zhi‐Wei
Published: October 2011

The concept of the damage boundary curve is the basic qualification in the evaluation of product fragility and in designing cushioning package systems. This paper investigates the dropping shock equations and dropping damage boundary curves for cubic and hyperbolic tangent cushioning systems based on the key component. The dropping damage boundary curves of key component are determined not only by the dropping height but also by the dimensionless fragility, damping ratio, frequency ratio, system parameter and mass ratio for this cushioning system. The results obtained in this paper and the previous paper presented by Z‐W. Wang compose the complete descriptions of product dropping damage boundary curves for linear and non‐linear packaging cushioning systems based on key component. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of maleic‐anhydride‐grafted polypropylene as a compatibilizer on the properties of polypropylene/(modified carbon black) composites
Authors: Li Qiuying , Wu Chifei , Zhu Ping
Published: October 2011

Maleic‐anhydride‐grafted polypropylene (PP‐g‐MAH) was added, as a compatibilizer, to polypropylene (PP) composites filled with a hindered phenol and modified carbon black (CB). The interaction between the modified CB and PP‐g‐MAH, as proved by Fourier transform infrared spectroscopy, had a beneficial effect on the mechanical properties of the PP/(modified CB) composites and prevented the sharp decrease of the mechanical properties of these composites at higher filler concentration. The storage modulus of PP/(modified CB) was increased significantly by the incorporation of PP‐g‐MAH, especially when the temperature was lower than 0°C. When the content of PP‐g‐MAH was 5 wt% and the loading of the modified CB was 2 wt%, the best tensile strength was obtained. The system showed the best flexural strength and impact strength when the loading of the modified CB was 1 wt%. J. VINYL ADDIT. TECHNOL., 2011. © 2011 Society of Plastics Engineers
HpYPS1 and HpYPS7 encode functional aspartyl proteases localized at the cell surface in the thermotolerant methylotrophic yeast Hansenula polymorpha
Authors: Sohn Min Jeong , Oh Doo‐Byoung , Kim Eun Jung , Cheon Seon Ah , Kwon Ohsuk , Kim Jeong‐Yoon , Lee Sang Yup , Kang Hyun Ah
Published: October 2011

In the present study, we functionally analysed two yapsin genes of the thermotolerant methylotrophic yeast Hansenula polymorpha, HpYPS1 and HpYPS7, for their roles in maintaining cell wall integrity and proteolytic processing. Both HpYPS1 and HpYPS7 proteins were shown to largely localize on the cell wall via glycosylphosphatidylinositol anchor. Heterologous expression of HpYPS1 completely restored all of the growth defects of the Saccharomyces cerevisiae yps1‐deletion strains, while HpYPS7 expression exhibited a limited complementation effect on the S. cerevisiae yps7‐deletion strain. However, different from S. cerevisiae, deletion of the HpYPS genes generated only minor influence on the sensitivity to cell wall stress. Likewise, HpYPS1 expression was significantly induced only by a subset of stressor agents, such as sodium dodecyl sulphate and tunicamycin. HpYps1p was shown to consist of two subunits, whereas HpYps7p comprises a single long polypeptide chain. Biochemical analysis revealed that HpYps1p has much stronger proteolytic cleavage activity at basic amino acids, compared to HpYps7p. Consistent with the much higher proteolytic activity and expression level of HpYps1p compared to HpYps7p, the sole disruption of HpYPS1 was sufficient in eliminating the aberrant proteolytic cleavage of recombinant proteins secreted by H. polymorpha. The results indicate that, although their roles in the maintenance of cell wall integrity are not critical, HpYps1p and HpYps7p are functional aspartic proteases at the cell surface of H. polymorpha. Furthermore, our data present the high biotechnological potential of H. polymorpha yps1‐mutant strains as hosts useful for the production of secretory recombinant proteins. Copyright © 2011 John Wiley & Sons, Ltd.
Isoperimetric inequalities for the first Neumann eigenvalue in Gauss space
Authors: Chiacchio F. , Di Blasio G.
Published: October 2011

We provide isoperimetric Szegö–Weinberger type inequalities for the first nontrivial Neumann eigenvalue

\mu _{1}(\Omega )

in Gauss space, where
Ω
is a possibly unbounded domain of

\mathbb{R}^{N}

. Our main result consists in showing that among all sets
Ω
of

\mathbb{R}^{N}

symmetric about the origin, having prescribed Gaussian measure,

\mu _{1}(\Omega )

is maximum if and only if
Ω
is the Euclidean ball centered at the origin.
Influence of confinement on a two-dimensional wake
Authors: Biancofiore Luca , Gallaire François , Pasquetti Richard
Published: October 2011

The spatio-temporal development of an incompressible two-dimensional viscous wake flow confined by two flat slipping plates is investigated by means of direct numerical simulation (DNS), using a spectral Chebyshev multi-domain method. The limit between unstable and stable configurations is determined with respect to several non-dimensional parameters: the confinement, the velocity ratio and two different Reynolds numbers, $100$ and $500$. The comparison of such limit curves with theoretical results obtained by Juniper (J. Fluid Mech., vol. 565, 2006, pp. 171–195) confirms the existence of a region at moderate confinement where the instability is maximal. Moreover, instabilities are also observed under sustained co-flow, in the form of a vacillating front. Using a direct computation of the two-dimensional base flow, we perform a local linear stability analysis for several velocity profiles prevailing at different spatial locations, so as to determine the local spatio-temporal nature of the flow: convectively unstable or absolutely unstable. Comparisons of the DNS and local stability analysis results are provided and discussed.
Effect of dietary arginine on growth, intestinal enzyme activities and gene expression in muscle, hepatopancreas and intestine of juvenile Jian carp (Cyprinus carpiovar. Jian)
Authors: Chen Gangfu , Feng Lin , Kuang Shengyao , Liu Yang , Jiang Jun , Hu Kai , Jiang Weidan , Li Shuhong , Tang Ling , Zhou Xiaoqiu
Published: October 2011

The present study was conducted to test the hypothesis that dietary arginine promotes digestion and absorption capacity, and, thus, enhances fish growth. This improvement might be related to the target of rapamycin (TOR) and eIF4E-binding protein (4E-BP). A total of 1200 juvenile Jian carp,Cyprinus carpiovar. Jian, with an average initial weight of 6·33 (se0·03) g, were fed with diets containing graded concentrations of arginine, namely, 9·8 (control), 12·7, 16·1, 18·5, 21·9 and 24·5 g arginine/kg diet for 9 weeks. An real-time quantitative PCR analysis was performed to determine the relative expression of TOR and 4E-BP in fish muscle, hepatopancreas and intestine. Dietary arginine increased (P < 0·05): (1) glutamate-oxaloacetate transaminase and glutamate-pyruvate transaminase activities in muscle and hepatopancreas; (2) intestine and hepatopancreas protein content, folds height, and trypsin, chymotrypsin, lipase, Na+/K+-ATPase, alkaline phosphatase, γ-glutamyl transpeptidase and creatine kinase activities in intestine; (3)Lactobacilluscounts; (4) relative expression of TOR in the muscle, hepatopancreas and distal intestine (DI); (5) relative expression of 4E-BP in proximal intestine (PI) and mid-intestine (MI), as compared with the control group. In contrast, dietary arginine reduced (P < 0·05): (1) plasma ammonia content; (2)Aeromonas hydrophilaandEscherichia colicounts; (3) relative expression of TOR in PI and MI; (4) relative expression of 4E-BP in the muscle, hepatopancreas and DI. The arginine requirement estimated by specific growth rate using quadratic regression analysis was found to be 18·0 g/kg diet. These results indicate that arginine improved fish growth, digestive and absorptive ability and regulated the expression ofTORand4E-BPgenes.
Habitat correlation of Symbiodinium diversity in two reef-building coral species in an upwelling region, eastern Hainan Island, China
Authors: Zhou G. , Huang H. , Lian J. , Zhang C. , Li X.
Published: October 2011

Reef-building corals are fundamental to the most diverse marine ecosystems, and the coral–dinoflagellate (zooxanthellae) associations on fine scale remains largely unknown. Spatial variation in the diversity of symbiotic dinoflagellates of two scleractinian coral species was studied in an upwelling region near Qinlan Harbor in eastern Hainan Island, China. Results showed that stress-tolerant Symbiodinium trenchi in individual colonies of Galaxea fascicularis occurred more frequently in shallow back-reef than in deep fore-reef. The higher symbiont diversity was found in colonies of G. fascicularis in shallow and close to the harbour mouth whereas the coral Pocillipora damicornis always harboured Symbiodinium internal transcribed spacer 2 (ITS2) types C1c or C42a. Furthermore, both corals were found to simultaneously contain Symbiodinium ITS2 types belonging to two distinct phylogenetic clades (C and D). This indicates that the distribution of genetically distinct Symbiodinium may correlate with light regime and possibly temperature in some (but not all) colonies at particular locations, which we interpret as holobiont acclimation to the local environmental conditions. Therefore, we conclude that reef-building corals can adapt to the local environment by harbouring genetically distinct symbionts but depend on their respective symbiont transmission modes.
Norm convergence of continuous-time polynomial multiple ergodic averages
Authors: AUSTIN TIM
Published: October 2011

For a jointly measurable probability-preserving actionτ:ℝD↷(X,μ) and a tuple of polynomial mapspi:ℝ→ℝD,i=1,2,…,k, the multiple ergodic averagesconverge inL2(μ) asT→∞for anyf1,f2,…,fk∈L∞(μ). This confirms the continuous-time analog of the conjectured norm convergence of discrete polynomial multiple ergodic averages, which in its original formulation remains open in most cases. A proof of convergence can be given based on the idea of passing up to a sated extension of (X,μ,τ) in order to find a simple partially characteristic factor, similarly to the recent development of this idea for the study of related discrete-time averages, together with a new inductive scheme on tuples of polynomials. The new induction scheme becomes available upon changing the time variable in the above integral by some fractional power, and provides an alternative to Bergelson’s polynomial ergodic theorem induction, which has been the mainstay of positive results in this area in the past.
Absenteeism in schools during the 2009 influenza A(H1N1) pandemic: a useful tool for early detection of influenza activity in the community?
Authors: KARA E. O. , ELLIOT A. J. , BAGNALL H. , FOORD D. G. F. , PNAISER R. , OSMAN H. , SMITH G. E. , OLOWOKURE B.
Published: October 2011

Certain influenza outbreaks, including the 2009 influenza A(H1N1) pandemic, can predominantly affect school-age children. Therefore the use of school absenteeism data has been considered as a potential tool for providing early warning of increasing influenza activity in the community. This study retrospectively evaluates the usefulness of these data by comparing them with existing syndromic surveillance systems and laboratory data. Weekly mean percentages of absenteeism in 373 state schools (children aged 4–18 years) in Birmingham, UK, from September 2006 to September 2009, were compared with established syndromic surveillance systems including a telephone health helpline, a general practitioner sentinel network and laboratory data for influenza. Correlation coefficients were used to examine the relationship between each syndromic system. In June 2009, school absenteeism generally peaked concomitantly with the existing influenza surveillance systems in England. Weekly school absenteeism surveillance would not have detected pandemic influenza A(H1N1) earlier but daily absenteeism data and the development of baselines could improve the timeliness of the system.
Understanding behavioral effects of early life stress using the reactive scope and allostatic load models
Authors: Howell Brittany R. , Sanchez Mar M.
Published: October 2011

The mechanisms through which early life stress leads to psychopathology are thought to involve allostatic load, the “wear and tear” an organism is subjected to as a consequence of sustained elevated levels of glucocorticoids caused by repeated/prolonged stress activations. The allostatic load model described this phenomenon, but has been criticized as inadequate to explain alterations associated with early adverse experience in some systems, including behavior, which cannot be entirely explained from an energy balance perspective. The reactive scope model has been more recently proposed and focuses less on energy balance and more on dynamic ranges of physiological and behavioral mediators. In this review we examine the mechanisms underlying the behavioral consequences of early life stress in the context of both these models. We focus on adverse experiences that involve mother–infant relationship disruption, and dissect those mechanisms involving maternal care as a regulator of development of neural circuits that control emotional and social behaviors in the offspring. We also discuss the evolutionary purpose of the plasticity in behavioral development, which has a clear adaptive value in a changing environment.
Influence of early life stress on later hypothalamic–pituitary–adrenal axis functioning and its covariation with mental health symptoms: A study of the allostatic process from childhood into adolescence
Authors: Essex Marilyn J. , Shirtcliff Elizabeth A. , Burk Linnea R. , Ruttle Paula L. , Klein Marjorie H. , Slattery Marcia J. , Kalin Ned H. , Armstrong Jeffrey M.
Published: October 2011

The hypothalamic–pituitary–adrenal (HPA) axis is a primary mechanism in the allostatic process through which early life stress (ELS) contributes to disease. Studies of the influence of ELS on children's HPA axis functioning have yielded inconsistent findings. To address this issue, the present study considers multiple types of ELS (maternal depression, paternal depression, and family expressed anger), mental health symptoms, and two components of HPA functioning (traitlike and epoch-specific activity) in a long-term prospective community study of 357 children. ELS was assessed during the infancy and preschool periods; mental health symptoms and cortisol were assessed at child ages 9, 11, 13, and 15 years. A three-level hierarchical linear model addressed questions regarding the influences of ELS on HPA functioning and its covariation with mental health symptoms. ELS influenced traitlike cortisol level and slope, with both hyper- and hypoarousal evident depending on type of ELS. Further, type(s) of ELS influenced covariation of epoch-specific HPA functioning and mental health symptoms, with a tighter coupling of HPA alterations with symptom severity among children exposed previously to ELS. Results highlight the importance of examining multiple types of ELS and dynamic HPA functioning in order to capture the allostatic process unfolding across the transition into adolescence.
Interactive effects of corticotropin releasing hormone receptor 1, serotonin transporter linked polymorphic region, and child maltreatment on diurnal cortisol regulation and internalizing symptomatology
Authors: Cicchetti Dante , Rogosch Fred A. , Oshri Assaf
Published: October 2011

Within an allostatic load framework, the effect of Gene × Environment (G × E) interactions on diurnal cortisol regulation and internalizing symptomatology were investigated. Variation in the corticotropin releasing hormone receptor 1(CRHR1)TAT haplotype and serotonin transporter linked polymorphic region (5-HTTLPR) was determined in a sample of maltreated (n= 238, 21.4% with early physical and sexual abuse) and nonmaltreated (n= 255) children (Mage = 10.08) participating in a summer research camp. Internalizing and depressive symptoms were assessed by other and self-report. G × E effects forCRHR1and maltreatment and early abuse on diurnal cortisol regulation were observed;CRHR1variation was related to cortisol dysregulation only among maltreated children. Early abuse and high internalizing symptoms also interacted to predict atypical diurnal cortisol regulation. The interaction ofCRHR1, 5-HTTLPR, and child maltreatment (G × G × E) identified a subgroup of maltreated children with high internalizing symptoms who shared the same combination of the two genes. The findings support an allostatic load perspective on the effects of the chronic stress associated with child maltreatment on cortisol regulation and internalizing symptomatology as moderated by genetic variation.
Risk factors for loss to follow-up among children and young adults with congenital heart disease
Authors: Mackie Andrew S. , Rempel Gwen R. , Rankin Kathryn N. , Nicholas David , Magill-Evans Joyce
Published: October 2011

Objective

To identify risk factors for loss to cardiology follow-up among children and young adults with congenital heart disease.

Methods

We used a matched case-control design. Cases were born before January, 2001 with moderate or complex congenital heart disease and were previously followed up in the paediatric or adult cardiology clinic, but not seen for 3 years or longer. Controls had been seen within 3 years. Controls were matched 3:1 to cases by year of birth and congenital heart disease lesion. Medical records were reviewed for potential risk factors for loss to follow-up. A subset of cases and controls participated in recorded telephone interviews.

Results

A total of 74 cases (66% male) were compared with 222 controls (61% male). A history of missed cardiology appointments was predictive of loss to follow-up for 3 years or longer (odds ratio 13.0, 95% confidence interval 3.3–51.7). Variables protective from loss to follow-up were higher family income (odds ratio 0.87 per $10,000 increase, 0.77–0.98), cardiac catheterisation within 5 years (odds ratio 0.2, 95% confidence interval 0.1–0.6), and chart documentation of the need for cardiology follow-up (odds ratio 0.4, 95% confidence interval 0.2–0.8). Cases lacked awareness of the importance of follow-up and identified primary care physicians as their primary source of information about the heart, rather than cardiologists. Unlike cases, controls had methods to remember appointments.

Conclusions

A history of one or more missed cardiology appointments predicted loss to follow-up for 3 or more years, as did lack of awareness of the need for follow-up. Higher family income, recent catheterisations, and medical record documentation of the need for follow-up were protective.
Neurocognitive Development and Behavioral Outcome of 2-Year-Old Children with Univentricular Heart
Authors: Puosi Riina , Korkman Marit , Sarajuuri Anne , Jokinen Eero , Mildh Leena , Mattila Ilkka , Lönnqvist Tuula
Published: October 2011

Recent advances in the treatment of children with severe congenital heart defects, such as hypoplastic left heart syndrome (HLHS) and other forms of univentricular heart (UVH), have significantly improved their survival rates. However, these children are at risk for various neurodevelopmental deficits. The aim of the present study was to assess cognitive development, expressive language, and behavior in 30-month-old children with univentricular heart. The participants were 22 children with HLHS, 14 with UVH, and 41 healthy control subjects. The Bayley Scales of Infant Development II, MacArthur Communicative Development Inventories, and Child Behavior Checklist were used for assessments. The results revealed that children with HLHS exhibited a significantly lower mean mental development index, more delays in expressive language functions, and more behavioral problems than did the control children. Two children with HLHS (9%) had mental development indexes below 50, indicating significantly delayed performance. The children with UVH differed from the control children with respect to their lower mean mental development index. These findings suggest that at the age of 30 months, neurodevelopmental deficits are especially prevalent in children with HLHS. Thus, early developmental screening, intervention, and neuropsychological follow-up until school age is recommended particularly for the children with HLHS. (JINS, 2011,17, 1094–1103)
Dietary patterns in Irish adolescents: a comparison of cluster and principal component analyses
Authors: Hearty Áine P , Gibney Michael J
Published: October 2011

Objective

Pattern analysis of adolescent diets may provide an important basis for nutritional health promotion. The aims of the present study were to examine and compare dietary patterns in adolescents using cluster analysis and principal component analysis (PCA) and to examine the impact of the format of the dietary variables on the solutions.

Design

Analysis was based on the Irish National Teens Food Survey, in which food intake data were collected using a semi-quantitative 7 d food diary. Thirty-two food groups were created and were expressed as either g/d or percentage contribution to total energy. Dietary patterns were identified using cluster analysis (k-means) and PCA.

Setting

Republic of Ireland, 2005–2006.

Subjects

A representative sample of 441 adolescents aged 13–17 years.

Results

Five clusters based on percentage contribution to total energy were identified, ‘Healthy’, ‘Unhealthy’, ‘Rice/Pasta dishes’, ‘Sandwich’ and ‘Breakfast cereal & Main meal-type foods’. Four principal components based on g/d were identified which explained 28 % of total variance: ‘Healthy foods’, ‘Traditional foods’, ‘Sandwich foods’ and ‘Unhealthy foods’.

Conclusions

A ‘Sandwich’ and an ‘Unhealthy’ pattern are the main dietary patterns in this sample. Patterns derived from either cluster analysis or PCA were comparable, although it appears that cluster analysis also identifies dietary patterns not identified through PCA, such as a ‘Breakfast cereal & Main meal-type foods’ pattern. Consideration of the format of the dietary variable is important as it can directly impact on the patterns obtained for both cluster analysis and PCA.
Contribution of street foods to the dietary needs of street food vendors in Kampala, Jinja and Masaka districts, Uganda
Authors: Namugumya Brenda Shenute , Muyanja Charles
Published: October 2011

Objectives

To assess the contribution of street foods to the energy and nutrient needs of street food vendors.

Design

A cross-sectional descriptive study was conducted. Food intake for the street food vendors was measured using the 24 h recall method and a semi-quantitative FFQ with emphasis on the source of all foods consumed.

Setting

Kampala, Jinja and Masaka districts, Uganda.

Subjects

The study included 225 street food vendors trading in prepared cooked foods.

Results

The majority of vendors (87·6 %) were women with age range of 21–50 years. Traditional dishes were the most commonly prepared foods and classified into main meals, sauces, vegetables and snacks. The food groups consumed most commonly by street food vendors fall under energy-giving and body-building foods (0·26 (sd0·81)). The mean daily intake of energy from street foods varied between 22·4 % and 25·6 % (2412 kJ). Carbohydrates contributed the highest proportion of energy (70·1 % to 93·4 %), followed by protein (38·6 % to 44·9 %) and fat (21·9 % to 26·3 %). Street food vendors obtained 24·0 % to 32·5 % of their RDA for Ca from street vended foods, with the lowest intake in Jinja (11·2 % to 23·9 %,P< 0·05). Niacin and thiamin intakes from street foods were respectively above 74 % and 150 % of the RDA. The contribution of street foods to the RDA for Zn ranged from 81·9 % to 190·9 %, and from 3·5 % to 4·9 % for retinol. Fe intake from street vended foods was 40·9 % to 49·7 % of the RDA.

Conclusions

Street foods contribute to sources of dietary energy and other nutrients among street food vendors in Uganda.
Normal and malignant megakaryopoiesis
Authors: Wen Qiang , Goldenson Benjamin , Crispino John D.
Published: October 2011

Megakaryopoiesis is the process by which bone marrow progenitor cells develop into mature megakaryocytes (MKs), which in turn produce platelets required for normal haemostasis. Over the past decade, molecular mechanisms that contribute to MK development and differentiation have begun to be elucidated. In this review, we provide an overview of megakaryopoiesis and summarise the latest developments in this field. Specially, we focus on polyploidisation, a unique form of the cell cycle that allows MKs to increase their DNA content, and the genes that regulate this process. In addition, because MKs have an important role in the pathogenesis of acute megakaryocytic leukaemia and a subset of myeloproliferative neoplasms, including essential thrombocythemia and primary myelofibrosis, we discuss the biology and genetics of these disorders. We anticipate that an increased understanding of normal MK differentiation will provide new insights into novel therapeutic approaches that will directly benefit patients.