bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-Destructive Estimation of Pernambuco (Caesalpinia Echinata) Clear Wood Properties Using near Infrared Spectroscopy
Authors: Schimleck Laurence R. , de Matos Jorge Luis Monteiro , da Silva Oliveira José Tarcisio , Muniz Graciela Inez Bolzon
Published: November 2011

Caesalpinia echinata Lam. (pernambuco or pau-brasil), is recognised as the premier raw material for manufacturing bows for stringed instruments. Owing to limited wood supplies and concerns regarding species survival, interest exists in establishing pernambuco plantations to provide bow quality wood in the future. Rapid methods for estimating wood quality are also required and we examined the estimation of density, modulus of elasticity (MOE), and modulus of rupture (MOR) using near infrared (NIR) spectra collected from the transverse surface of blocks cut from the end of 73 pernambuco clear wood samples. The samples represented three populations: plantation grown pernambuco 25 years old (19 samples) and 30 years old (26 samples) and native forest pernambuco (28 samples). NIR spectra were collected using two spectrometers: a Foss NIRSystems 5000 and an Analytical Spectral Devices, Inc., AgriSpec (ASD) spectrometer fitted with a fibre-optic probe. For individual populations, density had the strongest statistics followed by MOE and MOR, with the native forest woods providing the best calibrations. The limited variation of the plantation woods explained their weaker statistics. Calibrations based on the three populations combined provided strong R2c for density (0.89 Foss spectra, 0.85 ASD spectral and moderate R2c for MOE (0.77 Foss spectra, 0.72 ASD spectra), while MOR calibrations were weak. The success of calibrations based on ASD spectra suggests that NIR assessment of pernambuco wood properties in the field may be possible.
Annuitization Puzzles
Authors: Benartzi Shlomo , Previtero Alessandro , Thaler Richard H
Published: November 2011

In his Nobel Prize acceptance speech given in 1985, Franco Modigliani drew attention to the “annuitization puzzle”: that annuity contracts, other than pensions through group insurance, are extremely rare. Rational choice theory predicts that households will find annuities attractive at the onset of retirement because they address the risk of outliving one's income, but in fact, relatively few of those facing retirement choose to annuitize a substantial portion of their wealth. There is now a substantial literature on the behavioral economics of retirement saving, which has stressed that both behavioral and institutional factors play an important role in determining a household's saving accumulations. Self-control problems, inertia, and a lack of financial sophistication inhibit some households from providing an adequate retirement nest egg. However, interventions such as automatic enrollment and automatic escalation of saving over time as wages rise (the “save more tomorrow” plan) have shown success in overcoming these obstacles. We will show that the same behavioral and institutional factors that help explain savings behavior are also important in understanding 1) how families handle the process of decumulation once retirement commences and 2) why there seems to be so little demand to annuitize wealth at retirement.
The Case for a Progressive Tax: From Basic Research to Policy Recommendation
Authors: Diamond Peter , Saez Emmanuel
Published: November 2011

This paper presents the case for tax progressivity based on recent results in optimal tax theory. We consider the optimal progressivity of earnings taxation and whether capital income should be taxed. We critically discuss the academic research on these topics and when and how the results can be used for policy recommendations. We argue that a result from basic research is relevant for policy only if 1) it is based on economic mechanisms that are empirically relevant and first order to the problem, 2) it is reasonably robust to changes in the modeling assumptions, and 3) the policy prescription is implementable (i.e, is socially acceptable and not too complex). We obtain three policy recommendations from basic research that satisfy these criteria reasonably well. First, very high earners should be subject to high and rising marginal tax rates on earnings. Second, low-income families should be encouraged to work with earnings subsidies, which should then be phased-out with high implicit marginal tax rates. Third, capital income should be taxed. We explain why the famous zero marginal tax rate result for the top earner in the Mirrlees model and the zero capital income tax rate results of Chamley and Judd, and Atkinson and Stiglitz are not policy relevant in our view.
Metaplastic carcinoma of the breast: multimodality imaging and histopathologic assessment
Authors: Choi Bo Bae , Shu Kwang Sun
Published: November 2011

Background

Metaplastic carcinomas are ductal carcinomas that display metaplastic transformation of the glandular epithelium to non-glandular mesenchymal tissue. Metaplastic carcinoma has a poorer prognosis than most other breast cancers, so the differential diagnosis is important. Although many clinical and pathologic findings have been reported, to our knowledge, few imaging findings related to metaplastic carcinoma have been reported.

Purpose

To investigate whole-breast imaging findings, including mammography, sonography, MRI, and pathologic findings, including immunohistochemical studies of metaplastic carcinomas of the breast.

Material and Methods

We analyzed 33 cases of metaplastic carcinoma between January 2001 and January 2011. Mammography, ultrasonography, and MRI were recorded retrospectively using the American College of Radiology (ACR) breast imaging reporting and data system (BI-RADS) lexicon. Immunohistochemical studies of estrogen receptor (ER), progesterone receptor (PR), p53, and C-erbB-2 were performed.

Results

The most common mammographic findings were oval shape (37%), circumscribed margin (59%), and high density (74%). The most common sonographic findings were irregular shape (59.4%), microlobulated margin (41%), complex echogenicity (81%), parallel orientation (97%), and posterior acoustic enhancement (50%). Axillary lymph node metastases were noted for 25% of the sonographic examinations. On MRI, the most common findings of margin and shape were irregularity (57% and 52.4%, respectively). High signal intensity was the most common finding on T2-weighted images (57%). Immunohistochemical profile was negative for ER (91%, 29/32) and PR (81%, 26/32).

Conclusion

Metaplastic carcinomas might display more benign features and less axillary lymph node metastasis than IDC. High signal intensity on T2 MRI images and hormone receptor negativity would be helpful in differentiating this tumor from other breast cancers.
HIV-1 clade a infection and viral control: an immunological perspective on a case of underquantification
Authors: Westrop S J , Jackson A , Gazzard B , Imami N
Published: November 2011

Summary

Although a vast majority of HIV-1 -positive patients in the UK are infected with clade B virus, a large number of newly diagnosed cases of heterosexually transmitted HIV-1 are acquired abroad, in countries where non-B clade HIV-1 predominates. Since the development of the viral load assay in 1988, assessment of HIV-1 plasma viraemia has become an integral part of HIV clinical care; however, the contemporary viral load assay was developed and optimized for clade B HIV-1. Here we report the underquantification of viraemia in an individual infected with clade A virus, and the consequent initial classification of the patient as an HIV controller (HIC). Immunological investigations of interferon (IFN)-γ and lymphoproliferative responses to HIV-1 clade B antigens and peptides, in parallel with mitogenic stimulation, were performed. Subsequent comparison with responses observed within clade B-infected HIC led to viral sequencing, confirmation of infecting clade and recommendation of antiretroviral therapy initiation. We emphasize the growing need for awareness of possible limitations of the commonly used viral load assays, which cannot be relied upon unreservedly in a clinical setting. Furthermore, this case highlights the increasing need for more detailed investigation into both viral genetics and fitness when defining patients as HIC.
An evaluation of the early effects of a combination antiretroviral therapy programme on the management of AIDS-associated Kaposi's sarcoma in KwaZulu-Natal, South Africa
Authors: Mosam A , Uldrick T S , Shaik F , Carrara H , Aboobaker J , Coovadia H
Published: November 2011

Summary

Roll-out of combination antiretroviral therapy (cART) in South Africa should impact on AIDS-associated Kaposi's sarcoma (KS). Government provision began in 2003, with 23% coverage for World Health Organization (WHO) stage IVAIDS in 2006. To assess the effect of cART availability on KS management, we evaluated records from 701 KS patients seen at a tertiary oncology centre in KwaZulu-Natal, South Africa, from 1995 to 2006. Associations between cART use and measures of KS care were evaluated. cART availability was 0% prior to 2001, 9.6% (2001-2003) and 44% (2004-2006). Documentation of HIV status increased incrementally from 65% to 92%. cART was associated with chemotherapy administration: 56% on cART versus 17% not on cART (P < 0.001); and less loss to follow-up, 13% on cART versus 38% not on cART (P < 0.001). cART availability improves the care of AIDS-associated KS. Further increases in cART availability for this population are needed in South Africa.
Sexual health of transgender sex workers attending an inner-city genitourinary medicine clinic
Authors: Hill S C , Daniel J , Benzie A , Ayres J , King G , Smith A
Published: November 2011

Summary

Previous studies have reported high HIV prevalence among transgender sex workers (TSWs). We performed a retrospective case-note review of known TSWs attending our unit. In all, 16/24 (66.7%) of patients were diagnosed with at least one sexually transmitted infection (STI) and 7/24 (29.2%) reported intentional unprotected anal or vaginal intercourse, which may explain the high prevalence of HIV in our cohort (37.5%). TSWs disclosed high rates of substance misuse, violence and sexual assault, which may also contribute to the increased prevalence of STI in this group.
Microscopy for symptomatic men: not all symptoms are born equal
Authors: Lascar R M , Foo A S , Jungmann E
Published: November 2011

Summary

We reviewed microscopy results for symptomatic male patients in order to identify clinical correlates of urethritis as diagnosed by same-day microscopy. Higher polymorph counts were found in patients presenting with discharge, or discharge together with dysuria, but dysuria without discharge was strongly associated with negative urethral microscopy. Symptoms were strongly linked to microscopy outcome but partnerships were not linked to either symptoms or outcome.
The influence of male circumcision for HIV prevention on sexual behaviour among traditionally circumcised men in Cape Town, South Africa
Authors: Eaton L A , Cain D N , Agrawal A , Jooste S , Udemans N , Kalichman S C
Published: November 2011

We examined the relationship between HIV prevention beliefs related to male circumcision and sexual behaviour/sexually transmitted infection (STI) acquisition among traditionally circumcised men in Cape Town, South Africa. HIV-negative men (n = 304), circumcised for cultural/religious reasons, attending a health clinic in Cape Town, South Africa, completed cross-sectional surveys. Generalized linear models were used to analyse the relationships between unprotected vaginal sex acts, number of female sexual partners, STI diagnoses and male circumcision-related beliefs and risk perceptions. Men who were aware that circumcision offers protection against HIV (relative risk [RR] = 1.19, 95% confidence interval [CI] = 1.06-1.32, P < 0.01), endorsed risk compensation related to male circumcision (RR = 1.15, 95% CI = 1.11-1.12, P < 0.01) and perceived lower risk of HIV infection when circumcised (RR = 1.08, 95% CI = 1.04-1.12, P < 0.01) were more likely to report unprotected vaginal sex acts. Similar patterns were also identified when predicting number of female sexual partners. Men who were more likely to endorse risk compensation related to male circumcision were also more likely to be diagnosed with a chronic STI (odds ratio [OR] = 1.64, 95% CI = 1.06-2.53, P < 0.05). Our findings suggest that we must not overlook the effects of beliefs towards male circumcision for HIV prevention among men traditionally circumcised; doing so may undermine current efforts to reduce HIV transmission through male circumcision.
Compression stockings with moderate pressure are able to reduce chronic leg oedema
Authors: Mosti G , Picerni P , Partsch H
Published: November 2011

Aim

To compare the efficacy of compression stockings and inelastic, high-pressure bandages concerning leg volume reduction in patients with chronic leg oedema.

Material and methods

Forty-two legs of 30 patients with chronic leg oedema caused by venous stasis were randomized to receive a strong inelastic bandage (IB) or an elastic stocking (ES) exerting a pressure of 23–32 mmHg. Changes in leg oedema were assessed after two and seven days by water displacement volumetry, measurements of leg circumferences and of skin thickness by using Duplex ultrasound. Interface pressure was registered under the compression devices for seven days.

Results

There was no significant difference between stockings and bandages, which both produced a significant reduction in leg volume after two days (−9.6% [95% CI 7.5–11.8] by ES and −11.5% [95% CI 9.9–13.2%] by IB) and after seven days (−13.2% [95% CI 10.4–16.2] by ES and −15.6% [95% CI 12.8–18.4] by IB). Bandages showed a more pronounced reduction in leg circumference and in skin thickness in the calf region. The pressure of IB in the lying position fell from initially 63 to 22 mmHg after two days, but only from 33 to 26 mmHg under ES (median values). The optimal pressure range concerning oedema reduction was found between 40 and 60 mmHg, while higher pressures produced by bandages showed a negative correlation with volume reduction.

Conclusions

Compression stockings exerting a pressure of around 30 mmHg are nearly as effective as high-pressure bandages with an initial pressure over 60 mmHg in reducing chronic leg oedema.
All I want for coagulation
Authors: Nunn K P , Bridgett M R , Walters M R , Walker I
Published: November 2011

Evidence-based medicine underpins modern practice of medicine. This paper describes a fictional consultation between Santa Claus and a doctor regarding deep vein thrombosis (DVT) prophylaxis, giving a review of the evidence for DVT prophylaxis in travellers while exposing the difficulty in applying evidence to atypical clinical encounters. Medline and the Cochrane Library were searched, and guidelines reviewed. Keywords used were DVT, thromboembolism, deep vein thrombosis and air travel-related venous thromboembolism. All relevant studies found, have been included in this review, with additional studies identified from the references in these articles. In conclusion, compression stockings, with or without a one-off dose of either aspirin or heparin, are the most evidence-based approaches for prophylaxis in someone with established risk factors for DVT prior to a long-haul flight. Simple exercises should also be encouraged.
Outcomes following a dedicated period of research during surgical training
Authors: Stutchfield B M , Harrison E M , Wigmore S J , Parks R W , Garden O J
Published: November 2011

With recent ‘working-time'-related changes to surgical training structure, the value of dedicated research during surgical training has been questioned. Online survey examining career and academic outcomes following a period of surgically related dedicated research at a Scottish University between 1972 and 2007. Of 58 individuals identified, contact details were available for 49 and 43 (88%) responded. Ninety-five percent ( n = 41) of respondents continue to pursue a career in surgery and 41% ( n = 17) are currently in academic positions. Ninety-one percent ( n = 39) had published one or more first-author peer-reviewed articles directly related to their research, with 53% ( n = 23) publishing three or more. Respondents with a clinical component to their research published significantly more papers than those with purely laboratory-based research ( P = 0.04). Eighty-one percent ( n = 35) thought that research was necessary for career progression, but only 42% ( n = 18) felt research should be integral to training. In conclusion, the majority of surgical trainees completing a dedicated research period, published papers and continued to pursue a surgical career with a research interest. A period of dedicated research was thought necessary for career progression, but few thought dedicated research should be integral to surgical training.
Effect of intradermal anaesthesia on success rate and pain of intravenous cannulation: a randomized non-blind crossover study
Authors: Hendry F , Checketts M R , Mcleod G A
Published: November 2011

Intravenous cannulation is a commonly performed procedure. This study aimed to determine whether the success rate and pain of intravenous cannulation is affected by prior injection of intradermal lidocaine. Intravenous cannulation was performed twice in 45 healthy volunteers. Intradermal lidocaine was administered prior to one of these cannulations. The outcome measures were success or failure of cannulation, and pain of cannulation, measured with a 100 mm visual analogue pain scale. The success rate of intravenous cannulation with and without prior intradermal lidocaine was 54% and 76%, respectively. The difference was 22.0% (95% CI 1.5-27.8%; P = 0.03). Log-linear analysis for three-way interaction between the variables (outcome, vascular condition and use of lidocaine) showed a significant influence of vascular condition on outcome ( G 2 24.6, P < 0.001). The mean (SD) pain scores in the control and intervention group were 34.8 (21.0) and 13.6 (13.2) mm, respectively. The difference between the mean pain scores was 21.2 mm (95% CI 15.1-27.3 mm). In conclusion, the success rate of intravenous cannulation may be reduced with the use of intradermal lidocaine, but success rate is primarily dependent on vascular condition. Intradermal lidocaine achieves a clinically significant reduction in the pain of intravenous cannulation.
The Scottish Liver Transplant Unit: current and future perspectives
Authors: Mcnally S J , Wigmore S J
Published: November 2011

The Scottish Liver Transplant Unit (SLTU) opened in 1992 and has now performed over 900 liver transplants. During this time there have been major changes in both organ donation and transplantation. Currently liver transplantation is restricted by limited organ supply. Scotland has one of the lowest rates of organ donation in Europe and one of the most rapidly increasing rates of cirrhosis. The consequent waiting list mortality has driven innovations including increasing use of marginal grafts, organs donated after cardiac death, split-liver transplants and the development of living-donor liver transplantation. To maintain liver transplantation, there is an urgent need to increase organ donation rates and to find novel treatments which optimize outcomes from marginal grafts. This review addresses the surgical aspects of liver transplantation and how these have evolved over the two past decades. Major changes are currently underway in organ donation organization, and there is continuing refinement of organ treatment and storage. A number of measures to maintain and improve organ preservation and function are currently being evaluated in clinical trials, and cell therapy holds significant potential for the future. Scotland has a rising need for liver transplantation and the SLTU continues to provide high-quality care and to be at the forefront of the latest advances in organ transplantation.
Gastric Schwannoma or GIST: accuracy of preoperative diagnosis?
Authors: Guthrie G , Mullen R , Moses A
Published: November 2011

Mesenchymal cell tumours of the gastrointestinal tract are rare in western society. Gastrointestinal stromal tumour (GIST) is the most common of this group of tumours. Gastric schwannoma is rarer, accounting for only 0.2% of all gastric tumours and 4% of all benign gastric neoplasms. Indeed, schwannoma has only been recognized as a primary gastrointestinal tumour in the last 20 years through advances in pathological techniques. We report a rare case of gastric schwannoma, the endoscopic and radiological features of which were indistinguishable from a GIST. Due to the diagnostic uncertainty, surgical resection is the treatment of choice. Development of more reliable diagnostic methods, such as endoscopic core biopsy, may help the accuracy of preoperative diagnosis.
Nocardiosis complicated with Addison's disease
Authors: Roca B , Roca M
Published: November 2011

A 77-year-old woman presented with subacute respiratory symptoms which were demonstrated to be due to nocardiosis. After initial improvement with antimicrobial therapy, new symptoms appeared, consisting of persistent vomits, abdominal pain and hypotension, which led to the diagnosis of Addison's disease.
The case of King Richard III
Authors: Skrziepietz A
Published: November 2011

In this short essay we will discuss the possible diseases of King Richard III according to the descriptions in Shakespeare's plays King Richard III and Henry VI. Furthermore, it is shown that the description of the defeated enemy as physically and mentally deformed is part of a long tradition which has its roots in Ancient Greece.
Pulmonary Histologic Changes in Marfan Syndrome
Authors: Dyhdalo Kathryn , Farver Carol
Published: November 2011

Marfan syndrome is one of the most common connective tissue diseases and may manifest with a range of symptoms and pathologic changes. We present a retrospective series of 5 cases of patients with Marfan syndrome and pulmonary pathology. Patients were young to middle-aged adults with absent or minimal smoking histories and absent to severe clinical pulmonary symptoms. Tissue specimens were obtained from the surgical pathology and autopsy services. Histologic examination revealed a consistent pattern of distal acinar emphysema in all patients. Comparisons are made with other cystic-type diseases of the lung that may histologically mimic this pattern. This is the largest contemporary series of histologic pulmonary involvement of Marfan syndrome and the first to describe this pattern of pulmonary changes in this patient population.
Polyglutamine tracts as modulators of transcriptional activation from yeast to mammals
Authors: Atanesyan Lilit , Günther Viola , Dichtl Bernhard , Georgiev Oleg , Schaffner Walter
Published: November 2011

Microsatellite repeats are genetically unstable and subject to expansion and shrinkage. A subset of them, triplet repeats, can occur within the coding region and specify homomeric tracts of amino acids. Polyglutamine (polyQ) tracts are enriched in eukaryotic regulatory proteins, notably transcription factors, and we had shown before that they can contribute to transcriptional activation in mammalian cells. Here we generalize this finding by also including evolutionarily divergent organisms, namely, Drosophila and baker’s yeast. In all three systems, Gal4-based model transcription factors were more active if they harbored a polyQ tract, and the activity depended on the length of the tract. By contrast, a polyserine tract was inactive. PolyQs acted from either an internal or a C-terminal position, thus ruling out a merely structural ‘linker’ effect. Finally, a two-hybrid assay in mammalian cells showed that polyQ tracts can interact with each other, supporting the concept that a polyQ-containing transcription factor can recruit other factors with polyQ tracts or glutamine-rich activation domains. The widespread occurrence of polyQ repeats in regu­latory proteins suggests a beneficial role; in addition to the contribution to transcriptional activity, their genetic instability might help a species to adapt to changing environmental conditions in a potentially reversible manner.
Shaped hemocompatible aerogels from cellulose phosphates: preparation and properties
Authors: Liebner Falk , Dunareanu Ramona , Opietnik Martina , Haimer Emmerich , Wendland Martin , Werner Carsten , Maitz Manfred , Seib Philipp , Neouze Marie-Alexandra , Potthast Antje , Rosenau Thomas
Published: November 2011

Hemocompatible, shaped cellulose phosphate aerogels were obtained from phosphorylated cellulosic pulps of low degree of phosphorylation (DSP≤0.20) by dissolution in stabilized NMMO×H2O, shaping, reprecipitation with ethanol and subsequent scCO2 drying. The novel aerogels were found to be promising materials for cell scaffolding and bone grafting. Special features include their interconnected and spread porosity, highly porous surface and microstructure, good hemocompatibility, and suitable hydroxyl apatite-binding environment. Adsorption of Ca2+ ions to the phosphate groups did not invert the negative inflammatory response observed after phosphorylating cellulose, but increased platelet-dependent parameters of hemostasis.
Ultrastructural evaluation of compression wood-like properties of common juniper (Juniperus communis L.)
Authors: Hänninen Tuomas , Tukiainen Pekka , Svedström Kirsi , Serimaa Ritva , Saranpää Pekka , Kontturi Eero , Hughes Mark , Vuorinen Tapani
Published: November 2011

To date, very little is known about the ultrastructure of common juniper,Juniperus communisL (juniper). In this study, the mechanical properties of juniper, its chemistry and ultrastructure has been analyzed. The data are presented in comparison to the normal wood (NW) and compression wood (CW) of spruce. Helical grooves, which are a characteristic of CW, were clearly visible in micrographs of juniper. The angle of the grooves with respect to the fiber axis was ca. 40°, which correlates with the microfibril angle determined by X-ray diffraction. Data from 4-point bending tests show that juniper and spruce CW exhibited similar behavior. The elastic moduli of both species were only ca. half from that of NW spruce. The composition of juniper fibers resembled that of CW fiber with respect to high lignin and hemicelluloses contents. However, the galactose content in CW of juniper was low and in CW of spruce was high. Raman imaging clearly revealed that the lignin/cellulose ratio in the fiber cell wall of juniper was similar to that of NW spruce.
Reduction of formaldehyde emission from light MDF panels by adding chestnut shell flour
Authors: Ayrilmis Nadir , Kaymakci Alperen
Published: November 2011

Formaldehyde (FA) emission, dimensional stability, and mechanical properties of urea-formaldehyde (UF) resin-bonded light medium density fiberboards (MDFs) made of mixtures of hardwood fiber (Fagus orientalis Lipsky) and chestnut (Castanea sativa Mill.) shell flour have been evaluated. Six panel types were made of mixtures of the wood fiber and chestnut shell with ratios of 10/0, 9/1, 8/2, 7/3, 6/4, and 5/5 (by weight). FA emissions from the panels were significantly decreased with increasing content of the chestnut shell flour (CSF). However, the dimensional stability, the flexural properties, and the internal bond strength were negatively affected by increasing content of the shell flour. The FA reduction can be mainly attributed to a high amount of the phenolic extractives in the chestnut shell. Chestnut shell has a high potential as an effective FA scavenger in the manufacture of UF resin-bonded wood-based panels if optimized properly.
Selectivity for Spectral Motion as a Neural Computation for Encoding Natural Communication Signals in Bat Inferior Colliculus
Authors: Andoni Sari , Pollak George D.
Published: November 2011

This study examines the neural computations performed by neurons in the auditory system to be selective for the direction and velocity of signals sweeping upward or downward in frequency, termed spectral motion. We show that neurons in the auditory midbrain of Mexican free-tailed bats encode multiple spectrotemporal features of natural communication sounds. These features to which each neuron is tuned are nonlinearly combined to produce selectivity for spectral motion cues present in their conspecific calls, such as direction and velocity. We find that the neural computations resulting in selectivity for spectral motion are analogous to models of motion selectivity studied in vision. Our analysis revealed that auditory neurons in the inferior colliculus (IC) are avoiding spectrotemporal modulations that are redundant across different bat communication signals and are specifically tuned for modulations that distinguish each call from another by their frequency-modulated direction and velocity, suggesting that spectral motion is the neural computation through which IC neurons are encoding specific features of conspecific vocalizations.
One Action System or Two? Evidence for Common Central Preparatory Mechanisms in Voluntary and Stimulus-Driven Actions
Authors: Hughes Gethin , Schütz-Bosbach Simone , Waszak Florian
Published: November 2011

Human behavior is comprised of an interaction between intentionally driven actions and reactions to changes in the environment. Existing data are equivocal concerning the question of whether these two action systems are independent, involve different brain regions, or overlap. To address this question we investigated whether the degree to which the voluntary action system is activated at the time of stimulus onset predicts reaction times to external stimuli. We recorded event-related potentials while participants prepared and executed left- or right-hand voluntary actions, which were occasionally interrupted by a stimulus requiring either a left- or right-hand response. In trials where participants successfully performed the stimulus-driven response, increased voluntary motor preparation was associated with faster responses on congruent trials (where participants were preparing a voluntary action with the same hand that was then required by the target stimulus), and slower responses on incongruent trials. This suggests that early hand-specific activity in medial frontal cortex for voluntary action trials can be used by the stimulus-driven system to speed responding. This finding questions the clear distinction between voluntary and stimulus-driven action systems.
Sapap3Deletion Causes mGluR5-Dependent Silencing of AMPAR Synapses
Authors: Wan Yehong , Feng Guoping , Calakos Nicole
Published: November 2011

Synaptic transmission mediated by AMPA-type glutamate receptors (AMPARs) is regulated by scaffold proteins in the postsynaptic density. SAP90/PSD-95-associated protein 3 (SAPAP3) is a scaffold protein that is highly expressed in striatal excitatory synapses. While loss of SAPAP3 is known to cause obsessive-compulsive disorder-like behaviors in mice and reduce extracellular field potentials in the striatum, the mechanism by which SAPAP3 regulates excitatory neurotransmission is largely unknown. This study demonstrates thatSapap3deletion reduces AMPAR-mediated synaptic transmission in striatal medium spiny neurons (MSNs) through postsynaptic endocytosis of AMPARs. Striatal MSNs inSapap3KO mice have fewer synapses with AMPAR activity and a higher proportion of silent synapses. We further find that increased metabotropic glutamate receptor 5 (mGluR5) activity inSapap3KO mice underlies the decrease in AMPAR synaptic transmission and excessive synapse silencing. These findings suggest a model whereby the normal role of SAPAP3 is to inhibit mGluR5-driven endocytosis of AMPARs. The results of this study provide the first evidence for the mechanism by which the SAPAP family of scaffold proteins regulates AMPAR synaptic activity.
Use Dependence of Presynaptic Tenacity
Authors: Fisher-Lavie Arava , Zeidan Adel , Stern Michal , Garner Craig C. , Ziv Noam E.
Published: November 2011

Recent studies indicate that synaptic vesicles (SVs) are continuously interchanged among nearby synapses at very significant rates. These dynamics and the lack of obvious barriers confining synaptic vesicles to specific synapses would seem to challenge the ability of synapses to maintain a constant amount of synaptic vesicles over prolonged time scales. Moreover, the extensive mobilization of synaptic vesicles associated with presynaptic activity might be expected to intensify this challenge. Here we examined the ability of individual presynaptic boutons of rat hippocampal neurons to maintain their synaptic vesicle content, and the degree to which this ability is affected by continuous activity. We found that the synaptic vesicle content of individual boutons belonging to the same axons gradually changed over several hours, and that these changes occurred independently of activity. Intermittent stimulation for 1 h accelerated rates of vesicle pool size change. Interestingly, however, following stimulation cessation, vesicle pool size change rates gradually converged with basal change rates. Over similar time scales, active zones (AZs) exhibited substantial remodeling; yet, unlike synaptic vesicles, AZ remodeling was not affected by the stimulation paradigms used here. These findings indicate that enhanced activity levels can increase synaptic vesicle redistribution among nearby synapses, but also highlight the presence of forces that act to restore particular set points in terms of SV contents, and support a role for active zones in preserving such set points. These findings also indicate, however, that neither AZ size nor SV content set points are particularly stable, questioning the long-term tenacity of presynaptic specializations.
Robust Central Reduction of Amyloid-β in Humans with an Orally Available, Non-Peptidic β-Secretase Inhibitor
Authors: May Patrick C. , Dean Robert A. , Lowe Stephen L. , Martenyi Ferenc , Sheehan Scott M. , Boggs Leonard N. , Monk Scott A. , Mathes Brian M. , Mergott Dustin J. , Watson Brian M. , Stout Stephanie L. , Timm David E. , Smith LaBell Elizabeth , Gonzales Celedon R. , Nakano Masako , Jhee Stanford S. , Yen Mark , Ereshefsky Larry , Lindstrom Terry D. , Calligaro David O. , Cocke Patrick J. , Greg Hall D. , Friedrich Stuart , Citron Martin , Audia James E.
Published: November 2011

According to the amyloid cascade hypothesis, cerebral deposition of amyloid-β peptide (Aβ) is critical for Alzheimer's disease (AD) pathogenesis. Aβ generation is initiated when β-secretase (BACE1) cleaves the amyloid precursor protein. For more than a decade, BACE1 has been a prime target for designing drugs to prevent or treat AD. However, development of such agents has turned out to be extremely challenging, with major hurdles in cell penetration, oral bioavailability/metabolic clearance, and brain access. Using a fragment-based chemistry strategy, we have generated LY2811376 [(S)-4-(2,4-difluoro-5-pyrimidin-5-yl-phenyl)-4-methyl-5,6-dihydro-4H-[1,3]thiazin-2-ylamine], the first orally available non-peptidic BACE1 inhibitor that produces profound Aβ-lowering effects in animals. The biomarker changes obtained in preclinical animal models translate into man at doses of LY2811376 that were safe and well tolerated in healthy volunteers. Prominent and long-lasting Aβ reductions in lumbar CSF were measured after oral dosing of 30 or 90 mg of LY2811376. This represents the first translation of BACE1-driven biomarker changes in CNS from preclinical animal models to man. Because of toxicology findings identified in longer-term preclinical studies, this compound is no longer progressing in clinical development. However, BACE1 remains a viable target because the adverse effects reported here were recapitulated in LY2811376-treated BACE1 KO mice and thus are unrelated to BACE1 inhibition. The magnitude and duration of central Aβ reduction obtainable with BACE1 inhibition positions this protease as a tractable small-molecule target through which to test the amyloid hypothesis in man.
Synaptic Properties of Corticocortical Connections between the Primary and Secondary Visual Cortical Areas in the Mouse
Authors: De Pasquale Roberto , Sherman S. Murray
Published: November 2011

Despite the importance of corticocortical connections, few published studies have investigated the functional, synaptic properties of such connections in any species, because most studies have been purely anatomical or aimed at functional features other than synaptic properties. We recently published a study of synaptic properties of connections between the primary and secondary cortical auditory areas in brain slices from the mouse, and, in the present study, we aimed to extend this by performing analogous studies of the primary and secondary visual areas (V1 and V2). We found effectively the same results. That is, connections between V1 and V2 in both directions were quite similar; in each case, the glutamatergic inputs could be classified as one of two types, Class 1B (formerly “driver”) and Class 2 (formerly “modulator”). There is a clear laminar correlation for these different inputs, in terms of both the laminae of origin and those in which the recorded cells were located. Our data suggest a common pattern to the functional organization of corticocortical connectivity in the mouse cortex.
Authentically Phosphorylated α-Synuclein at Ser129 Accelerates Neurodegeneration in a Rat Model of Familial Parkinson's Disease
Authors: Sato Hiroyasu , Arawaka Shigeki , Hara Susumu , Fukushima Shingo , Koga Kaori , Koyama Shingo , Kato Takeo
Published: November 2011

Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons in the substantia nigra (SN) and the appearance of fibrillar aggregates of insoluble α-synuclein (α-syn) called Lewy bodies (LBs). Approximately 90% of α-syn deposited in LBs is phosphorylated at serine 129 (Ser129). In contrast, only 4% of total α-syn is phosphorylated in normal brain, suggesting that accumulation of Ser129-phosphorylated α-syn is involved in the pathogenesis of PD. However, the role of Ser129 phosphorylation in α-syn neurotoxicity remains unclear. In this study, we coexpressed familial PD-linked A53T α-syn and G-protein-coupled receptor kinase 6 (GRK6) in the rat SN pars compacta using recombinant adeno-associated virus 2. Coexpression of these proteins yielded abundant Ser129-phosphorylated α-syn and significantly exacerbated degeneration of dopaminergic neurons when compared with coexpression of A53T α-syn and GFP. Immunohistochemical analysis revealed that Ser129-phosphorylated α-syn was preferentially distributed to swollen neurites. However, biochemical analysis showed that the increased expression of Ser129-phosphorylated α-syn did not promote accumulation of detergent-insoluble α-syn. Coexpression of catalytically inactive K215R mutant GRK6 failed to accelerate A53T α-syn-induced degeneration. Furthermore, introducing a phosphorylation-incompetent mutation, S129A, into A53T α-syn did not alter the pace of degeneration, even when GRK6 was coexpressed. Our study demonstrates that authentically Ser129-phosphorylated α-syn accelerates A53T α-syn neurotoxicity without the formation of detergent-insoluble α-syn, and suggests that the degenerative process could be constrained by inhibiting the kinase that phosphorylates α-syn at Ser129.
A Roman Road in the Dutch Republic
Authors: Abrahamse Jaap Evert
Published: November 2011

Jacob van Campen, the most distinguished architect of the Dutch Republic during its seventeenth-century Golden Age, is identified as the designer of Amersfoortweg (the Amersfoort Road) in A Roman Road in the Dutch Republic. This large-scale landscape architecture project was conceived to improve transportation in the province of Utrecht and also to catalyze the transformation of a large wasteland into a landscape of prosperous agricultural estates. The grandiose roadway, over sixty meters wide and lined with trees, ran perfectly straight for most of the route between Utrecht and Amersfoort. Jaap Evert Abrahamse argues that Van Campen and his clients created Amersfoortweg on the model of the ancient Roman roads that they had read about in the Renaissance treatises that were beginning to circulate in the Netherlands.
Polychrome Roof Tiles and National Style in Nineteenth-century Croatia
Authors: Damjanović Dragan
Published: November 2011

Gothic architecture, revived and decorated with motifs borrowed from folk art, provided the foundation for the creation of a Croatian national style in the last quarter of the nineteenth century. Dragan Damjanović explains how the Viennese architect Friedrich Schmidt and his student and collaborator Herman Bollé created the signature architecture of this movement, the brilliantly colored and boldly patterned tile roofs of St. Mark's church (restored 1875–82), Zagreb cathedral (restored 1878–1902), and the church of the Blessed Virgin Mary in Marija Bistrica (restored 1878–85). In Polychrome Roof Tiles and National Style in Nineteenth-century Croatia, this architecture is placed in the context of the Gothic Revival in the Austro-Hungarian monarchy and the collecting and analysis of traditional textiles by the amateur ethnographer Felix (Srećko) Lay.
Alloying-Driven Phase Stability in Group-VB Transition Metals under Compression
Authors: Landa Alexander , Söderlind Per
Published: November 2011

The change in phase stability of Group-VB (V, Nb, and Ta) transition metals due to pressure and alloying is explored by means of first-principles electronic-structure calculations. It is shown that under compression stabilization or destabilization of the ground-state body-centered cubic (bcc) phase of the metal is mainly dictated by the band-structure energy that correlates well with the position of the Kohn anomaly in the transverse acoustic phonon mode. The predicted position of the Kohn anomaly in V, Nb, and Ta is found to be in a good agreement with data from the inelastic x-ray or neutron scattering measurements. In the case of alloying the change in phase stability is defined by the interplay between the band-structure and Madelung energies. We show that band-structure effects determine phase stability when a particular Group-VB metal is alloyed with its nearest neighbors within the same d-transition series: the neighbor with less and more d electrons destabilize and stabilize the bcc phase, respectively. When V is alloyed with neighbors of a higher (4d- or 5d-) transition series, both electrostatic Madelung and band-structure energies stabilize the body-centered-cubic phase. The opposite effect (destabilization) happens when Nb or Ta is alloyed with neighbors of the 3d-transition series.
Warning system based on theoretical-experimental study of dispersion of soluble pollutants in rivers
Authors: Ribeiro Celso B. de M. , Silva Demétrius D. da , Soares José H. P. , Guedes Hugo A. S.
Published: November 2011

Information about capacity of transport and dispersion of soluble pollutants in natural streams are important in the management of water resources, especially in planning preventive measures to minimize the problems caused by accidental or intentional waste, in public health and economic activities that depend on the use of water. Considering this importance, this study aimed to develop a warning system for rivers, based on experimental techniques using tracers and analytical equations of one-dimensional transport of soluble pollutants conservative, to subsidizing the decision-making in the management of water resources. The system was development in JAVA programming language and MySQL database can predict the travel time of pollutants clouds from a point of eviction and graphically displays the temporal distribution of concentrations of passage clouds, in a particular location, downstream from the point of its launch.
Ingestão de resíduos antropogênicos por tartarugas marinhas no litoral norte do estado da Bahia, Brasil
Authors: Macedo Gustavo Rodamilans , Pires Thaís Torres , Rostán Gonzalo , Goldberg Daphne Wrobel , Leal Danielle Custódio , Garcez Neto Américo Fróes , Franke Carlos Roberto
Published: November 2011

Este trabalho descreve a presença de resíduos antropogênicos no trato digestório de tartarugas marinhas no Litoral Norte da Bahia, Brasil. Foram realizadas necropsias no trato digestório de 45 tartarugas marinhas encontradas mortas (Chelonia mydas n=36; Eretmochelys imbricata n=9), no período de janeiro de 2006 a outubro de 2007. Em 60% (27/45) das tartarugas necropsiadas foram encontrados resíduos, especialmente aqueles relacionados à atividade de pesca. Os resíduos encontravam-se ao longo de todo o trato gastrointestinal, com predominância no intestino grosso. A ingestão de resíduos pelas tartarugas marinhas do Litoral Norte da Bahia pode levar a debilidade e até mesmo provocar a morte destes animais.
Adenocarcinoma renal metastático em uma Codorna Japonesa (Coturnix coturnix japonica)
Authors: Casagrande Renata Assis , Laskoski Fernanada , Traverso Sandra Davi , Kanamura Cristina Takima , Gava Aldo
Published: November 2011

Uma codorna japonesa (Coturnix coturnix japonica), fêmea, adulta com 2 anos apresentou parada de postura, emagrecimento, aumento de volume abdominal e morte. Ao exame macroscópico, observou-se ascite, pulmão esquerdo difusamente esbranquiçado, massas esbranquiçadas, de aproximadamente 1,0cm de diâmetro, na região caudal do lobo direito do fígado e na serosa da moela; massas de 0,1 a 0,5cm no mesentério e serosa intestinal; e uma massa de 5,0x2,0cm na fossa do sinsacro, que acometia 90% do parênquima renal e estendia-se ao ovário e oviduto. Na avaliação histopatológica da neoformação renal, observou-se proliferação de células epiteliais formando túbulos, que muitas vezes não apresentavam lúmen, sustentados por um estroma fibrovascular escasso associado à necrose multifocal. As células neoplásicas eram cuboidais, núcleos redondos a ovalados, nucléolos evidentes, citoplasma abundante e eosinofílico, pleomorfismo moderado e poucas figuras mitóticas. Metástases foram observadas de forma difusa no ovário, oviduto e pulmão esquerdo; multifocal na serosa do intestino e focal no fígado e camadas muscular e serosa da moela. Na avaliação imuno-histoquímica, as células tumorais foram positivas para a citoqueratina (clones AE1+AE3) e negativas para a citoqueratina 5/6, o CD10 e a fosfatase alcalina placentária. De acordo com a localização, achados morfológicos e o perfil imuno-histoquímico, conclui-se que o presente relato trata-se de um adenocarcinoma renal metastático.