bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous resolution of an infantile hemangioma in a dorsal root ganglion
Authors: Hervey-Jumper Shawn L. , McKeever Paul E. , Gebarski Stephen S. , Muraszko Karin M. , Maher Cormac O.
Published: December 2011

Infantile hemangiomas are tumors commonly seen in children. Few authors have reported infantile hemangiomas affecting the CNS, and there are no prior reports detailing spontaneous resolution of a histologically proven juvenile hemangioma within a dorsal root ganglion. The authors report the case of a newborn boy with a large cutaneous hemangioma in the midline of his back. Spinal MR images were obtained to rule out associated spinal cord tethering, and an intradural spinal lesion was unexpectedly discovered. Biopsy revealed an intradural infantile hemangioma within the dorsal root ganglion, and, based on this diagnosis, no resection was performed. Sixteen months following the biopsy, the cutaneous hemangioma had become involuted and the intradural hemangioma had completely resolved. The behavior of the intradural component in this case follows the natural history of many cutaneous infantile hemangiomas.
Strategies for asymptomatic carotid artery stenosis
Authors: Doe Christopher , Jethwa Pinakin R. , Gandhi Chirag D. , Prestigiacomo Charles J.
Published: December 2011

The treatment of asymptomatic carotid artery stenosis (ACAS) has continued to evolve for the past 3 decades. With rapidly advancing technology, the results of old trials have become obsolete. While there has been little change in the efficacy of carotid endarterectomy, there have been vast improvements in both medical management and carotid angioplasty with stenting. Finding the best therapy for a given patient can therefore be difficult. In this article, the authors review the current literature regarding treatment options for ACAS and the methods available for stratifying patients who would benefit from surgical versus medical treatment.
Clinical considerations in the management of asymptomatic carotid artery stenosis
Authors: Taussky Philipp , Hanel Ricardo A. , Meyer Fredric B.
Published: December 2011

Incidental findings pose considerable management dilemmas for the treating physician and psychological burden for the respective patient. With an aging population, more patients will be diagnosed with asymptomatic internal carotid artery stenosis. Patients will have to be counseled with regard to treatment options according to their individual risk profile and according to professionals' knowledge of evidence-based data derived from large randomized control trials. Treatment consensus has long been lacking for patients with asymptomatic carotid artery stenosis prior to any randomized controlled trials. Additionally, an individual's risk profile may be hard to assess according to knowledge gained from randomized controlled trials. Moreover, while earlier studies compared carotid endarterectomy and medical therapy, in the past years, a new therapeutic modality, carotid artery angioplasty and stenting, has emerged as a possible alternative. This has been evaluated in a recent randomized controlled trial, the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), which compared carotid endarterectomy with angioplasty and stenting in both symptomatic and asymptomatic patients. The following review summarizes current knowledge of the natural history, diagnosis, and treatment strategies to counsel patients with asymptomatic carotid artery stenosis.
Incidental os odontoideum: current management strategies
Authors: Klimo Paul , Coon Valerie , Brockmeyer Douglas
Published: December 2011

Os odontoideum was first described in the late 1880s and still remains a mystery in many respects. The genesis of os odontoideum is thought to be prior bone injury to the odontoid, but a developmental cause probably also exists. The spectrum of presentation is striking and ranges from patients who are asymptomatic or have only neck pain to those with acute quadriplegia, chronic myelopathy, or even sudden death. By definition, the presence of an os odontoideum renders the C1–2 region unstable, even under physiological loads in some patients. The consequences of this instability are exemplified by numerous cases in the literature in which a patient with os odontoideum has suffered a spinal cord injury after minor trauma. Although there is little debate that patients with os odontoideum and clinical or radiographic evidence of neurological injury or spinal cord compression should undergo surgery, the dispute continues regarding the care of asymptomatic patients whose os odontoideum is discovered incidentally. The authors' clinical experience leads them to believe that certain subgroups of asymptomatic patients should be strongly considered for surgery. These subgroups include those who are young, have anatomy favorable for surgical intervention, and show evidence of instability on flexion-extension cervical spine x-rays. This recommendation is bolstered by the fact that surgical fusion of the C1–2 region has evolved greatly and can now be done with considerable safety and success. When atlantoaxial instrumentation is used, fusion rates for os odontoideum should approach 100%.
Comparison of Unenhanced and Enhanced Imaging Protocols for Angle Measurements With Anterior Segment Optical Coherence Tomography
Authors: Deokule Sunil , Alencar Luciana , Vizzeri Gianmarco , Medeiros Felipe , Weinreb Robert N.
Published: December 2011

BACKGROUND AND OBJECTIVE:

To compare the intraobserver and interobserver agreement of anterior chamber angle measurements using unenhanced and enhanced imaging protocols for anterior segment optical coherence tomography (AS-OCT).

PATIENTS AND METHODS:

Anterior segments of 30 eyes of 15 healthy subjects (mean age: 33.8 ± 13.0 years, 8 women) were imaged by a single examiner with AS-OCT using unenhanced and enhanced imaging protocol. Two masked observers analyzed each image independently on two separate occasions. The reproducibility of angle parameters was estimated by calculating coefficients of variation separately for each observer. Bland–Altman plots were constructed to assess the intraobserver and interobserver agreement.

RESULTS:

The intraobserver and interobserver reproducibility was similar between imaging protocols. Intra-observer and interobserver agreements were also similar for all parameters evaluated. The best estimate of scleral spur location was determined in all images by both observers.

CONCLUSION:

Measurement variability was similar with the unenhanced and enhanced imaging protocol in this series of eyes with open angles.
Managing Agitated Behaviour in People with Alzheimer's Disease: The Role of Live Music
Authors: Cox Elissa , Nowak Madeleine , Buettner Petra
Published: December 2011

Background:

Agitation due to Alzheimer's disease (AD) presents a challenge to occupational therapists working in the older people care sector. Recently, background music and music therapy have emerged as promising tools in the management of agitation in AD. This exploratory study investigated whether live music could reduce agitated behaviour in people with AD.

Method:

A quasi-experimental one-group repeated measures design investigated the effect of a live, one-to-one, musical violin intervention on agitated behaviour in people with moderate-severe AD in a residential care facility. Seven participants received the musical intervention on three occasions. Participants were video recorded before, during and after each session. Behaviour was assessed by the investigator and a blinded assessor, using an investigator-modified Cohen-Mansfield Agitation Inventory. Thirty agitated behaviours were examined. Data were analysed using the Friedman test.

Results:

This intervention reduced agitated behaviour among participants. Significant reductions in pacing/aimless wandering (p = 0.023), performing repetitious mannerisms (p = 0.036) and general restlessness (p = 0.007) were observed. The total number of agitated behaviours decreased significantly (median 5 [range 2–8] behaviours before the intervention to 1 [range 0–4] during and 1 [range 0–5] after the intervention [p = 0.005]).

Conclusion:

Live music may be an effective strategy to reduce short-term agitated behaviour among people with AD.
Elastomeric Impression Materials: A Comparison of Accuracy of Multiple Pours
Authors: Kumar Dheeraj , Madihalli Anand U , Reddy K Rajeev Kumar , Rastogi Namrataa , Pradeep NT
Published: December 2011

Aim

The aim of the present study is to compare the various elastomeric impression materials in terms of accuracy and dimensional stability, with respect to obtaining multiple casts from a single elastomeric impression at various times of pours.

Materials and methods

Three master dies were prepared for the impression making, two of these were made of brass containing a central hole with undercuts. The third die simulated a conventionally prepared typodont maxillary central incisor. Three elastomeric impression materials were chosen for the study. Each impression was poured at various time periods. Casts thus obtained were evaluated under a traveling microscope to evaluate various dimensional changes.

Results

Addition silicones provided dies which were shorter in height and bigger in diameter. Polyethers provided dies which were shorter in both height and diameter. Condensation silicones showed insignificant changes from the master die at the immediate pour but deteriorated rapidly after that in subsequent pours.

Conclusion

None of the impression material showed a consistent behavior up to the fourth pour. They occasionally showed deviation from the pattern, but all these values were statistically insignificant. Polyethers showed lesser ability than both the addition silicones as well as the condensation silicones to recover from induced deformation.

Clinical significance

Addition silicones as well as the condensation silicones have better ability to recover from induced deformation when compared to polyether.

How to cite this article

Kumar D, Madihalli AU, Reddy KRK, Rastogi N, Pradeep NT. Elastomeric Impression Materials: A Comparison of Accuracy of Multiple Pours. J Contemp Dent Pract 2011;12(4):272-278.
Transformation Through Research‐Based Reflection: A Self‐Study of Written Feedback Practice
Authors: BEST KAREN
Published: December 2011

This study investigates the written feedback the author gave during her first year as a university English as a second language writing instructor. The article investigates the form (questions, commands, comments) and the themes (organization, content, grammar) of feedback, the use of mitigation, and the treatment of grammar errors. It shows how practitioner research can increase one's confidence, provide an accurate understanding of one's own work, and more fully establish one's practice in theory, rather than teaching lore.
Wind forcing of salinity anomalies in the Denmark Strait overflow
Authors: Hall S. , Dye S. R. , Heywood K. J. , Wadley M. R.
Published: December 2011

Abstract. The overflow of dense water from the Nordic Seas to the North Atlantic through Denmark Strait is an important part of the global thermohaline circulation. The salinity of the overflow plume has been measured by an array of current meters across the continental slope off the coast of Angmagssalik, southeast Greenland since September 1998. During 2004 the salinity of the overflow plume changed dramatically; the entire width of the array (70 km) freshened between January 2004 and July 2004, with a significant negative salinity anomaly of about 0.06 in May. The event in May represents a fresh anomaly of over 3 standard deviations from the mean since recording began in 1998. The OCCAM 1/12° Ocean General Circulation Model not only reproduces the 2004 freshening event (r=0.96, p<0.01), but also correlates well with salinity observations over a previous 6 year period (r=0.54, p<0.01), despite the inevitable limitations of a z-coordinate model in representing the mixing processes at and downstream of the Denmark Strait sill. Consequently the physical processes causing the 2004 anomaly and prior variability in salinity are investigated using the model output. Our results reject the hypotheses that the anomaly is caused by processes occurring between the overflow sill and the moorings, or by an increase in upstream net freshwater input. Instead, we show that the 2004 salinity anomaly is caused by an increase in volume flux of low salinity water, with a potential density greater than 27.60 kg m−3, flowing towards the Denmark Strait sill in the East Greenland Current. This is caused by an increase in southward wind stress upstream of the sill at around 75° N 20° W four and a half months earlier, and an associated strengthening of the East Greenland Current.
Soviet Conceptualizations of the Iranian Revolution
Authors: Nation R. Craig
Published: December 2011

In the five years that have passed since the fall of the shah and the creation of the Islamic Republic of Iran, the hopes expressed in these early evaluations have been broadly disappointed. If on one hand the institutional framework built-up under the charismatic leadership of Ayatollah Ruhallah Khumayni and his Islamic Republican Party (IRP) has proven relatively stable, the nature of "Islamic" institutions has evolved in unexpected directions. The revolution has not created a significantly improved climate of relations between Iran and the USSR, and the vision of a revolutionary process pushing and with Western Europe. Soviet evaluations of the Iranian revolution have soured accordingly. 4 Setting the tone for the more critical perspective which now dominates Soviet one prestigious commentator has emphasized the reactionary forces within the Iranian leadership and the regime as an "Islamic despotism."
The Polish Economy in the Year 2000: Need and Outlook for Systemic Reforms, Recovery and Growth Strategy
Authors: Fallenbuchl Zbigniew , Marer Paul
Published: December 2011

The prospects for economic development in Poland for the rest of this century depend on the ability of the authorities to handle a number of very serious obstacles that presently face the economy. If the constraints imposed by these obstacles are significantly reduced during the second half of the 1980s, a considerable improvement may take place during the 1990s. If, however, the authorities choose to follow present economic policies without modification, prolonged stagnation will likely continue. The final outcome will, of course, also depend on a number of external factors beyond the authorities' control, such as the state of the political and economic situation in the world and within the Warsaw Pact Bloc, East-West political and economic relations or the occurrence of some unforeseen natural or man-made ecological disaster. Assuming, however, no big changes in exogenous factors, the economic situation in Poland in the year 2000 will primarily be determined by the authorities' policies within the next few years.
The Water Management Crisis in Soviet Central Asia
Authors: Micklin Philip P.
Published: December 2011

Water is biologically essential to all life. Without an adequate supply plants and animals soon perish. But an abundant and assured supply of fresh water is also an economic and social necessity to modem industrial societies which withdraw prodigious amounts of it, chiefly for industrial, agricultural, and municipal purposes. Massive water withdrawals are particularly essential in arid regions where irrigation has been extensively developed. However, since irrigation is a major consumptive user of water (i.e., a large proportion of water withdrawn is not returned directly to the supply source), rivers and ground water suffer significant depletion with attendant ecological, economic, and social consequences.
New Members and Organs: The Politics of Porn
Authors: Goscilo Helena
Published: December 2011

Until perestroika, finding pornography in Moscow was less likely than encountering a singing nun at a bazaar. Yet by 1990 Moscow News reported a lively trade in girlie magazines at newsstands, an adolescent complained to Vecherniaia Moskva (Moscow at Night) about the pornographic videos inundating the city, and metro stations and dashboards of taxis routinely displayed pictures of women wearing only a pout or a smile. Public reactions to the relentless omnipresence of naked flesh pressured Gorbachev, in fact, to establish a commission on 5 December 1990 charged with elaborating measures to safeguard the country's morality. Anyone curious about the effectiveness of that official body may consult reflections on the topic by one of its members-published in the glossy Playboy clone Andrei.
The Far-Left in Postcommunist Hungary: The Workers' Party
Authors: Racz Barnabas
Published: December 2011

The emotional euphoria of the East European regime changes in 1989-1990 and the subsequent implosion of the Soviet system led to a widespread view in both West and East that communist parties would disappear and become a matter of only historical interest. Closer analysis of political processes raised doubts about this view. Whatever rational or irrational reactions emerged about the post-Soviet communist parties, they were forces deeply rooted in twentieth century history and were unlikely to disappear in a quantum leap of change. It is the hypothesis of this inquiry into the radical left, which had enjoyed considerable support in the aftermath of World War II, that it was capable of surviving the crisis and may remain a part of the political realities for some time to come.
Misperceptions Between Japan and Russia
Authors: Verbitsky Semyon , Hasegawa Tsuyoshi , Rozman Gilbert
Published: December 2011

The twentieth century has witnessed repeated occasions when Japan and Russia have taken each other's measure and decided on policy accordingly. In the years 1985 to 1999 such mutual testing occuned again amidst adjustments in the direction of each country's global role. As has often been the case, the RussoJapanese relationship was not the main event on the world stage. Both countries placed higher priority on relations with the United States and with China. But to rank this bilateral relationship below two others is not to belittle the stakes involved. For Russia, Tokyo's strategy to look east or west and within Asia to focus in the northeast or the southeast has throughout the century made a great difference in war or peace, in development or isolation. For Japan, Moscow's strategy to balance west and east, and in the east to concentrate on China or Japan, has had telling consequences for other foreign policy choices. At stake in this bilateral relationship have been the development of Siberia and the Russian Far East; the security environment in Northeast Asia including Korea; the prospects of triangular or quadrangular relations with China and the United States; and the balance of power among the world's great powers.
The Early Cold War in Soviet West Ukraine, 1944–1948
Authors: Burds Jeffrey
Published: December 2011

In 1989, when archival discoveries were about to revolutionize the history of the Cold War, John Lewis Gaddis published a pathbreaking article entitled “Intelligence, Espionage and Cold War Origins.” While Gaddis expressed serious doubts as to whether anyone had ever established that espionage had positively affected larger historical developments, he did render one sober and perceptive conclusion that did not rely on unencumbered access to Soviet, American, or British archives: espionage had heightened the atmosphere of distrust on all sides, and probably did more to escalate tensions than to abate them. “Was it all worth it, from the Russians’ own standpoint? There is good reason to doubt whether the benefi ts Stalin gained from spying on his allies during and after the war counterbalanced the problems created for him once his indulgence in espionage became known.”
Natural Disaster and Human Actions in the Soviet Famine of 1931–1933
Authors: Tauger Mark B.
Published: December 2011

Until recently both scholarly and popular discussions of the catastrophic famine in the Soviet Union in 1931-1933 invariably have described it as an artificial or ''manmade" famine. Certain well-known scholars have dominated this discussion, expressing two main interpretations of the famine. A Ukrainian nationalist interpretation holds that the Soviet regime, and specifically losif Stalin, intentionally imposed the famine to suppress the nationalist aspirations of Ukraine and Ukrainians; revisionists argue that the leadership imposed the famine to suppress more widespread peasant resistance to collectivization. According to these views, a natural disaster that could have caused a famine did not take place in those years.
Menorrhagia and bleeding disorders in adolescent females
Authors: Halimeh S.
Published: December 2011

In women, von Willebrand disease (VWD) is the most common inherited bleeding disorder. Since VWD and other inherited bleeding disorders are autosomal disorders, they affect women and men. Menorrhagia, or heavy menstrual bleeding (HMB), is the most common symptom of women with bleeding disorder experience. Objectively, it is defined as bleeding that lasts for more than seven days or results in the loss of more than 80 ml of blood per menstrual cycle. The prevalence of menorrhagia in a woman with a bleeding disorder ranges from 32 to 100% in patients with VWD, from 5 to 98% in patients with a platelet dysfunction and from 35 to 70% in women with a rare factor deficiency. A detailed history and a careful physical exam are the first steps towards a diagnosis in adolescents, adding a PBAC > 100 increased the sensitivity of the screening tool further to 95%. Laboratory testing should be made at the time of menstrual bleeding in an effort to capture the lowest level of VWF : Ag and FVIII : C. Treatment options for menorrhagia in VWD: antifibrinolytic therapy with tranexamic acid, (2) the non-transfusional agent desmopressin (DDAVP), (3) purified blood products that contain factor VIII and VWF concentrated from plasma and (4) hormonal preparations.
Gradient‐enhanced TROSY described with Cartesian product operators
Authors: Zuiderweg Erik R.P. , Rousaki Aikaterini
Published: November 2011

TROSY, Transverse Relaxation Optimized Spectroscopy, was developed more than a decade ago. Since that time, the 15N‐1H HSQC‐TROSY experiment has become the standard “fingerprint” correlation spectrum for proteins of high molecular weight. In addition, its implementation in protein triple resonance experiments has pushed the boundaries of NMR assignment up to about 100 kDa, making NMR a highly relevant technique in structural biology. TROSY exploits the dipole‐CSA cross‐correlated relaxation properties of the NH system and selects for the narrowest of the HSQC J‐correlation quartet in both dimensions. The original publications and reviews of TROSY use shift operators and/or single transition product operators to describe the TROSY coherence pathways selections. In this review, we offer a familiar Cartesian product operator approach to comprehensively describe all of the events in the modern TROSY pulse sequence such as multiplet selection, gradient coherence selection, gradient quadrature, and sensitivity enhancement. © 2011 Wiley Periodicals, Inc. Concepts Magn Reson Part A 38: 280–288, 2011.
Theoretical modeling of 13C NMR chemical shifts—How to use the calculation results
Authors: Gryff‐Keller Adam
Published: November 2011

Owing to wide accessibility of the general utility quantum chemistry programs, theoretical calculations of spectral parameters defining NMR spectra have become relatively easy for medium size molecules. This new and powerful tool allows investigators to perform much deeper interpretation of the NMR data and gain new information valuable for structural chemistry studies. It is usually realized and well understood that theoretical calculations of NMR parameters, as for any quantum mechanical calculations, have several limitations, difficult to overcome, and that the accuracy of calculation results is strongly dependent on the theoretical method applied. On the other hand, it is less commonly recognized that the effectiveness of all the combined calculational/spectroscopic approach depends meaningfully on the method of comparison of the experimental and theoretical data as well. This article is addressed primarily to experimental chemists who use in their everyday work 13C NMR spectroscopy to solve various structural and physicochemical problems. After recalling some basic concepts concerning NMR parameters and their calculations, some suggestions concerning the rational choice of the calculational method and the experiment/theory comparison method are formulated. To support these recommendations and convince the reader of their utility, several practical examples are presented in the text. All these concepts reflect the author's beliefs which, albeit well‐grounded, by no means should be treated as indispensable truths; they are rather worth considering as hints about how to solve various practical dilemmas. © 2011 Wiley Periodicals, Inc. Concepts Magn Reson Part A 38: 289–307, 2011.
Prevalence of diabetes mellitus secondary to pancreatic diseases (type 3c)
Authors: Ewald N. , Kaufmann C. , Raspe A. , Kloer H. U. , Bretzel R. G. , Hardt P. D.
Published: November 2011

Background

Diabetes mellitus secondary to pancreatic diseases is a condition seldom thought of in clinical practice. Yet, a high percentage of exocrine pancreatic insufficiency has been reported for the general population and especially for diabetic subjects. Thus, we investigated the prevalence of diabetes mellitus due to pancreatic diseases.

Methods

In this study, we investigated 1868 patients diagnosed with diabetes mellitus who had been admitted to our hospital during the last 24 months. Patient data were diligently studied, and patients were reclassified according to the diabetes classification as proposed by the American Diabetes Association.

Results

Among 1868 subjects, 172 patients could be classified as type 3c diabetes mellitus (9.2%). Among these were 135 diagnosed with chronic pancreatitis (78.5%), 12 with hereditary haemochromatosis, 14 with pancreatic cancer and 7 with cystic fibrosis. Thus, diabetes mellitus due to chronic pancreatitis occurred in this collective in 7.2% of all diabetic subjects. Misclassification of these patients was very common. Only 51.2% (88/172) were initially classified correctly. Most type 3 diabetes patients were initially misclassified as type 2 diabetes (69/84).

Conclusions

Diabetes mellitus secondary to pancreatic diseases (especially chronic pancreatitis) seems more common than generally believed with a prevalence of 9.2% among the subjects studied here. Because the awareness of this diabetes type is poor, misclassification is quite frequent. A common problem seems to be the differentiation between type 2 and type 3. Yet, the right classification of diabetes mellitus is important, because there are special therapeutic options and problems in patients with diabetes secondary to pancreatic diseases. Copyright © 2011 John Wiley & Sons, Ltd.
The Sox17‐mCherry fusion mouse line allows visualization of endoderm and vascular endothelial development
Authors: Burtscher Ingo , Barkey Wenke , Schwarzfischer Michael , Theis Fabian J. , Lickert Heiko
Published: November 2011

Sox17 is a HMG‐box transcription factor that has been shown to play important roles in both cardio‐vascular development and endoderm formation. To analyze these processes in greater detail, we have generated a Sox17‐mCherry fusion (SCF) protein by gene targeting in ES cells. SCF reporter mice are homozygous viable and faithfully reflect the endogenous Sox17 protein localization. We report that SCF positive cells constitute a subpopulation in the visceral endoderm before gastrulation and time‐lapse imaging reveals that SCF monitors the nascent definitive endoderm during epithelialization. After gastrulation, SCF marks the mid‐ and hindgut endoderm and vascular endothelial network, which can be imaged during establishment in allantois explant cultures. The SCF reporter is downregulated in the endoderm epithelium and upregulated in endothelial cells of the intestine, lung, and pancreas during organogenesis. In summary, the generation of the Sox17‐mCherry reporter mouse line allows direct visualization of endoderm and vascular development in culture and the mouse embryo. genesis 50:496–505, 2012. © 2011 Wiley Periodicals, Inc.
Historical variability and feedbacks among land cover, stream power, and channel geometry along the lower Canadian River floodplain in Oklahoma
Authors: Julian Jason P. , Thomas Richard E. , Moursi Sayed , Hoagland Bruce W. , Tarhule Aondover
Published: November 2011

In 1820, the lower Canadian River meandered through a densely forested floodplain. By 1898, most of the floodplain had been cleared for agriculture and changes in channel geometry and specific stream power followed, particularly channel widening and straightening with a lower potential specific stream power. In 1964, a large upstream hydropower dam was constructed, which changed the flow regime in the lower Canadian River and consequently the channel geometry. Without destructive overbank floods, the channel narrowed rapidly and considerably due to encroachment by floodplain vegetation. The lower Canadian River, which was once a highly dynamic floodplain‐river system, has now been transformed into a relatively static river channel. These changes over the past 200 years have not been linear or independent. In this article, we use a variety of data sources to assess these historical changes along the lower Canadian River floodplain and identify feedbacks among floodplain cultivation, dam construction, specific stream power, and channel width, slope, and sinuosity. Finally, we combine the results of our study with others in the region to present a biogeomorphic response model for large Great Plains rivers that characterizes channel width changes in response to climate variability and anthropogenic disturbances. Copyright © 2011 John Wiley & Sons, Ltd.
Role of low-density lipoprotein receptor in the hepatitis C virus life cycle
Authors: Albecka Anna , Belouzard Sandrine , de Beeck Anne Op , Descamps Véronique , Goueslain Lucie , Bertrand-Michel Justine , Tercé François , Duverlie Gilles , Rouillé Yves , Dubuisson Jean
Published: November 2011

Hepatitis C virus (HCV) particles are known to be in complex with lipoproteins. As a result of this interaction, the low-density lipoprotein (LDL) receptor (LDLR) has been proposed as a potential entry factor for HCV; however, its implication in virus entry remains unclear. Here, we reinvestigated the role of the LDLR in the HCV life cycle by comparing virus entry to the mechanism of lipoprotein uptake. A small interfering RNA targeting the LDLR in Huh-7 cells reduced HCV infectivity, confirming that this receptor plays a role in the life cycle of HCV generated in cell culture. However, kinetics of internalization were much faster for lipoproteins than for infectious HCV particles. Furthermore, a decrease in HCV RNA replication was observed by blocking the LDLR with a specific antibody, and this was associated with an increase in the ratio of phosphatidylethanolamine to phosphatidylcholine in host cells. Nevertheless, a soluble form of the LDLR inhibited both HCV entry into the hepatocytes and its binding to the LDLR expressed on Chinese hamster ovary cells, suggesting a direct interaction between the HCV particle and the LDLR. Finally, we showed that modification of HCV particles by lipoprotein lipase (LPL) reduces HCV infectivity and increases HCV binding to LDLR. Importantly, LPL treatment also induced an increase in RNA internalization, suggesting that LDLR, at least in some conditions, leads to nonproductive internalization of HCV. Conclusion: The LDLR is not essential for infectious HCV particle entry, whereas the physiological function of this receptor is important for optimal replication of the HCV genome. (Hepatology 2012)
Phospholipid transfer activity of microsomal triglyceride transfer protein produces apolipoprotein B and reduces hepatosteatosis while maintaining low plasma lipids in mice
Authors: Khatun Irani , Zeissig Sebastian , Iqbal Jahangir , Wang Minghui , Curiel David , Shelness Gregory S. , Blumberg Richard S. , Hussain Mahmood M.
Published: November 2011

Microsomal triglyceride transfer protein (MTP), essential for apolipoprotein B (apoB) biosynthesis, evolved as a phospholipid transfer protein and acquired triglyceride transfer activity during a transition from invertebrates to vertebrates. But it is unknown whether MTP directly transfers lipids onto apoB

in vivo

and, if it does, whether both neutral and polar lipid transfer activities of MTP are critical for lipoprotein assembly. The molecular bases for differences in lipid transfer activities with respect to distinct domains in

Drosophila

MTP (dMTP) and human MTP (hMTP) are not obvious because both proteins have very similar primary, secondary, and tertiary structures. We used an

in vivo

approach to delineate physiological significance of these distinct lipid transfer activities by expressing dMTP (transfers phospholipids) and hMTP (transfers phospholipids and triglycerides) orthologs using adenoviruses in liver-specific MTP-deficient (L-MTP−/−) mice that have low plasma and high hepatic lipids. Both orthologs improved plasma lipids but plasma triglycerides were lower in dMTP mice due to lower hepatic triglyceride and apoB production. Hepatosteatosis in L-MTP−/− mice was ameliorated to similar levels by both. Attenuation of hepatosteatosis upon dMTP expression pertained to enhanced β-oxidation with no changes in lipogenesis. Phospholipid transfer activity of MTP promoted biogenesis of both apoB48 and apoB100-containing very low density lipoprotein in addition to a phospholipid-rich apoB48-containing high-density lipoprotein particle. Triglyceride transfer activity augmented the biosynthesis of triglyceride-rich lipoproteins by increasing the formation of these particles in the lumen of the endoplasmic reticulum.

Conclusion :

Based on these findings, we posit that the selective inhibition of MTP triglyceride transfer activity might reduce hyperlipidemia while protecting liver from excess lipid accumulation. (Hepatology 2011)
Role of glial cells in manganese neurotoxicity
Authors: Filipov Nikolay M. , Dodd Celia A.
Published: November 2011

The objectives of this focused review are to (i) provide a systematic overview of recent advances pertaining to the role of glia, namely microglia and astrocytes, in the neuropathology associated with excessive exposure to manganese (Mn), (ii) highlight possible mechanisms and factors involved in Mn‐modulated, glia‐derived neuroinflammation, and (iii) discuss the implications of excessive neuroinflammation on neuronal injury within the context of Mn overexposure. As this is not meant to be a comprehensive review on the topic of Mn neurotoxicity, the reader may wish to refer to several broader and more comprehensive reviews. After a brief introduction to Mn neurotoxicity, we first discuss the role of glial cells in neurodegeneration. Next, we review existing in vitro and in vivo studies that implicate Mn as a modulator of glial activation and ensuing neuroinflammation. This is followed by an examination of recognized and potential mechanisms that are involved in the modulation of glial inflammatory output by Mn; here the common pathways activated by Mn in glial and neuronal cells, including outcomes of such activation, are also addressed. We finish with a discussion of the implications of Mn‐modulated glial activation for neuronal survival and with a list of data gaps in the topic that need to be filled in the future. Copyright © 2011 John Wiley & Sons, Ltd.
Cardiovascular risk assessment of atypical antipsychotic drugs in a zebrafish model
Authors: Lee Sung Hak , Kim Hong Rye , Han Rong Xun , Oqani Reza K. , Jin Dong Il
Published: November 2011

The zebrafish model has been developed and evaluated for its ability to predict the toxicity of chemicals. Zebrafish additionally serve as an excellent model for assessing drug‐induced cardiotoxicity, although zebrafish and mammalian hearts differ in structure. Recently, regulatory authorities have expressed concerns about a possible relationship between antipsychotics and risk of QTc interval prolongation, serious arrhythmia and sudden cardiac death. In the current study, we performed a cardiovascular risk assessment of six atypical antipsychotic drugs in zebrafish, specifically, aripiprazole, clozapine, olanzapine, quetiapine, risperidone and ziprasidone. Visual endpoints, such as lethality, edema (the presence of heart and trunk edema), hemorrhage (clustering of a pool of blood in an area outside the normal circulation), abnormal body shape (including bent or misshapen caudal region of the larvae) and motility, were evaluated as general toxicity endpoints, and the heart beat rate calculated as the cardiovascular toxicity endpoint. The zebrafish model facilitates determination of the heart beat rate, and may thus be an attractive screening tool for cardiovascular risk assessment of atypical antipsychotic drugs to understand the variations in response to QT‐prolonging drugs. Copyright © 2011 John Wiley & Sons, Ltd.
Development and optimization of a novel genetic algorithm for identifying nanoclusters from scanning transmission electron microscopy images
Authors: Logsdail Andrew J. , Li Z. Y. , Johnston Roy L.
Published: November 2011

Whilst technological advancements have allowed imaging at atomic resolution using scanning transmission electron microscopy (STEM), identification of nanocluster structures has proven difficult due to their low thermal stability, and often resultant low‐symmetry. In this work, we look at a novel solution to this problem using a genetic algorithm (GA). GAs are search methods for the minimization of statistical problems based on natural evolution. We develop a STEM model first described by Curley et al. (2007) and, using high‐symmetry cluster structures as test subjects, look at the effectiveness and efficiency of the GA at optimizing orientation parameters for a cluster when compared to a model solution. We find for a 309‐atom icosahedron that a random minimizing search would prove more efficient than a GA; however, for a 309‐atom decahedron the GA becomes more effective and efficient than a random search. We predict that as we continue to lower symmetry of our test cases, we will find the GA becomes even more efficient at optimizing this otherwise computationally expensive problem. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012
Temporoparietal fascia free flap for pharyngeal coverage after salvage total laryngectomy
Authors: Higgins Kevin M. , Ashford Bruce , Erovic Boban M. , Yoo John , Enepekides Danny J.
Published: November 2011

Objectives/Hypothesis:

The aim of this study was to assess whether the use of the temporoparietal fascia as a free flap for pharyngeal closure reinforcement reduced the incidence of pharyngocutaneous fistula (PCF) in the salvage setting.

Study Design:

Consecutive case series.

Methods:

After research ethics board approval, 12 patients who required salvage laryngectomy, including reinforcement coverage of the primarily closed pharyngeal defect with temporoparietal fascia as a free tissue transfer, were analyzed.

Results:

One (8%) out of 12 patients experienced pharyngocutaneous fistula that responded with conservative wound packing.

Conclusions:

The PCF rate of 8% is significantly better than in similar salvage cases without flap coverage. Moreover, our PCF rate is comparable to the results shown for the pectoralis major muscle flap. The most obvious benefit of the temporoparietal fascia free flap for pharyngeal coverage in salvage laryngectomy is a reduced PCF rate with diminished donor‐site morbidity, including cosmetic outcome, shoulder girdle function, and chest deformity.
Not just another face in the crowd: Society's perceptions of facial paralysis
Authors: Ishii Lisa , Godoy Andres , Encarnacion Carlos O. , Byrne Patrick J. , Boahene Kofi D. O. , Ishii Masaru
Published: November 2011

Objectives/Hypothesis:

There is a paucity of data showing the perception penalty caused by facial paralysis. Our objective was to measure society's perception of facial paralysis on the characteristic of beauty. We hypothesized that patients with paralysis would be considered by society as less attractive than normals, a difference amplified by smiling.

Study Design:

Randomized controlled experiment.

Methods:

Forty subjects viewed photographs of normal and paralyzed faces. They rated attractiveness, identified paralysis if present, its severity, and the feature most affected.

Results:

There were significant differences in attractiveness scores for normal and paralyzed faces (Wilcoxon rank sum test, z = 16.912; P < .001). A mixed effects regression model was used to explain differences in the scores. The fixed portion of the model shows paralyzed faces were 1 standard deviation less attractive than normal faces. Smiling increased attractiveness for normals (constant, 5.9; smile effect, 0.735; P < .001). The smile × paralysis interaction term was −0.892; P < .001, but not significantly different from the smile term (χ2(1) = 0.87; P = .352). The random effects model showed an intersubject rating variability of 1.32.

Conclusions:

The attractiveness penalty imposed by facial paralysis is significant, with paralyzed faces considered markedly less attractive than normals. However, the ratings did not change significantly when patients smiled, despite the increased asymmetry that occurs through smiling. Observers were moderately good at identifying the presence of facial paralysis, but less good at distinguishing side of involvement. These results have important implications for patient counseling and management of facial paralysis patients in an evidence‐based manner.
Position of the hyoid and larynx in people with muscle tension dysphonia
Authors: Lowell Soren Y. , Kelley Richard T. , Colton Raymond H. , Smith Patrick B. , Portnoy Joel E.
Published: November 2011

Objectives/Hypothesis:

To determine whether radiographic measures of hyoid position, laryngeal position, and hyolaryngeal space during phonation were different for people with primary muscle tension dysphonia (MTD) as compared to control participants without voice disorders.

Study Design:

Prospective, quasi‐experimental research design.

Methods:

Twenty participants, 10 with primary MTD and 10 without voice disorders who were age and sex matched were studied radiographically while producing phonation. Lateral x‐ray images were obtained for each participant during three tasks: resting state, sustained phonation, and a swallow‐hold maneuver. Vertical positions of the hyoid and larynx were measured on a Cartesian coordinate system and were normalized to reflect change from rest during phonation.

Results:

Normalized, vertical hyoid, and laryngeal positions during phonation were significantly higher for people with MTD than for control participants. Normalized hyolaryngeal space during phonation did not show differences between groups. A low to moderate significant correlation for radiographically measured hyoid and laryngeal position and the total score from a subjective laryngeal palpatory scale were evidenced, but no relationship was evidenced for radiographic laryngeal position and the laryngeal position subscore of the palpatory examination.

Conclusions:

Objective determinants of physiology are critical for the differential diagnosis of MTD and its effective treatment. Radiographic findings from this study indicate that hyoid and laryngeal positions during phonation are higher in people with primary MTD as compared to people without voice disorders.
Enucleation of vagal nerve schwannoma using intraoperative nerve monitoring
Authors: Gibber Marc J. , Zevallos Jose P. , Urken Mark L.
Published: November 2011

Vagal nerve schwannomas are rare, benign, neural sheath tumors. The treatment of enlarging or symptomatic vagal nerve schwannomas is surgical resection. Transecting the vagus nerve results in significant morbidity, and attempts at nerve preservation should be made whenever possible. We introduce a nerve‐sparing technique using meticulous microsurgical dissection and intraoperative nerve monitoring for vagal schwannomas. A 61‐year old patient presented with an enlarging 2‐cm right vagal nerve schwannoma. She underwent resection via a transcervical approach. The patient was intubated with an electromyographic (EMG) endotracheal tube that allowed for monitoring of the recurrent laryngeal nerve intraoperatively. A microsurgical subcapsular dissection was performed after branches of the vagus nerve were identified using a nerve probe and preserved. At the conclusion of the resection the nerve was intact and stimulated along its entire course. Postoperatively, the patient had normal vagal nerve function. We introduced the role of intraoperative nerve monitoring using an EMG endotracheal tube for successful enucleation of vagal schwannomas. In conjunction with meticulous microsurgical dissection, nerve monitoring allows for successful preservation of the vagus nerve and decreased postoperative morbidity. Laryngoscope, 2012
Detection of intracochlear damage during cochlear implant electrode insertion using extracochlear measurements in the gerbil
Authors: Ahmad Faisal I. , Choudhury Baishakhi , De Mason Christine E. , Adunka Oliver F. , Finley Charles C. , Fitzpatrick Douglas C.
Published: November 2011

Objectives/Hypothesis:

An intraoperative monitoring algorithm during cochlear implant electrode insertion could be used to detect trauma and guide electrode placement relative to surviving hair cells. The aim of this report was to assess the feasibility of using extracochlear recording sites to monitor acoustically evoked responses from surviving hair cells and neural elements during implantation in an animal model.

Study Design:

Animal experiments.

Methods:

The normal‐hearing gerbil was used. Two recording methods, one using a lock‐in amplifier and another using Fourier analysis of recorded signals, were used to obtain frequency‐specific information about the responses to tones. Amplitude and threshold determinations were made at the round window and at three extracochlear sites. To induce intracochlear damage, a platinum‐iridium wire was inserted through the round window. The wire was advanced, and changes in the potentials were correlated with cochlear contact. Anatomic integrity was assessed using cochlea whole mount preparations.

Results:

In general, the lock‐in amplifier showed greater sensitivity and lower thresholds at higher frequencies relative to the Fourier method. Also, the lock‐in amplifier was more resistant to masking effects. Both systems were able to detect loss of cochlear potentials secondary to intracochlear trauma. Histologic damage was seen in all cases and corresponded to electrophysiologic changes.

Conclusions:

Impact of electrodes on cochlear structures affecting cochlear performance could be detected from several extracochlear sites. The lock‐in amplifier demonstrated greater sensitivity and resistance to noise when compared to the fast Fourier transform recording paradigm. The latter showed greater flexibility of detecting and separating hair cell and neural potentials.