bluuebunny/crossref_metadata_2025_split huggingface dataset:
Forebrain and hindbrain development in zebrafish is sensitive to ethanol exposure involving agrin, Fgf, and sonic hedgehog function
Authors: Zhang Chengjin , Ojiaku Princess , Cole Gregory J. 
Published: November 2012

AbstractBACKGROUND: Ethanol is a teratogen that affects numerous developmental processes in the nervous system, which includes development and survival of GABAergic and glutamatergic neurons. Possible molecular mechanisms accounting for ethanol's effects on nervous system development include perturbed fibroblast growth factor (Fgf) and Sonic hedgehog (Shh) signaling. In zebrafish, forebrain GABAergic neuron development is dependent on Fgf19 and Shh signaling. The present study was conducted to test the hypothesis that ethanol affects GABAergic and glutamatergic neuron development by disrupting Fgf, Shh, and agrin function. METHODS: Zebrafish embryos were exposed to varying concentrations of ethanol during a range of developmental stages, in the absence or presence of morpholino oligonucleotides (MOs) that disrupt agrin or Shh function. In situ hybridization was used to analyze glutamic acid decarboxylase (GAD1) gene expression, as well as markers of glutamatergic neurons. RESULTS: Acute ethanol exposure results in marked reduction in GAD1 gene expression in forebrain and hindbrain, and reduction of glutamatergic neuronal markers in hindbrain. Subthreshold ethanol exposure, combined with agrin or Shh MO treatment, produces a similar diminution in expression of markers for GABAergic and glutamatergic neurons. Consistent with the ethanol effects on Fgf and Shh pathways, Fgf19, Fgf8, or Shh mRNA overexpression rescues ethanol‐induced decreases in GAD1 and Atonal1a gene expression. CONCLUSIONS: These studies demonstrate that GABAergic and glutamatergic neuron development in zebrafish forebrain or cerebellum is sensitive to ethanol exposure, and provides additional evidence that a signaling pathway involving agrin, Fgfs and Shh may be a critical target of ethanol exposure during zebrafish embryogenesis. Birth Defects Research (Part A), 2013. © 2012 Wiley Periodicals, Inc.
Prophylactic central neck dissection for papillary thyroid cancer
Authors: Barczyński M , Konturek A , Stopa M , Nowak W 
Published: November 2012

Abstract

Background
Prophylactic central neck dissection (CND) for papillary thyroid cancer (PTC) remains controversial. The aim of this study was to examine whether prophylactic CND for PTC affected long-term survival and locoregional control.

Methods
This was a retrospective cohort study of patients who underwent total thyroidectomy (TT) with bilateral prophylactic CND. They were compared with patients who had TT without CND. Personalized adjuvant radioiodine treatment was used in both groups. Primary outcomes were overall and disease-specific survival, and locoregional control. Secondary outcomes were number of patients with negative serum thyroglobulin levels, and morbidity.

Results
Of 640 patients with PTC included in this study, 282 (treated in 1993–1997) had TT without CND and 358 (treated in 1998–2002) underwent TT with CND. The 10-year disease-specific survival rate for patients who had TT without CND was 92·5 per cent compared with 98·0 per cent in patients with CND (P = 0·034), and the locoregional control rate was 87·6 and 94·5 per cent respectively (P = 0·003). In multivariable analysis, extrathyroidal extension was an independent predictive factor for locoregional recurrence (odds ratio 12·47, 95 per cent confidence interval 6·74 to 23·06; P &lt; 0·001), whereas CND was an independent predictive factor for improved locoregional control at 10 years after surgery (odds ratio 0·21, 0·11 to 0·41; P &lt; 0·001). No differences were seen in the rates of permanent hypoparathyroidism or recurrent laryngeal nerve injury between the groups.

Conclusion
Bilateral prophylactic CND for staging of the neck in PTC, followed by personalized adjuvant radioiodine treatment, improved both 10-year disease-specific survival and locoregional control, without increasing the risk of permanent morbidity. Registration number: NCT01510002 (http://www.clinicaltrials.gov).
Assessment of the selection process for myocutaneous flap repair and surgical complications in pelvic exenteration surgery
Authors: Jacombs A S W , Rome P , Harrison J D , Solomon M J 
Published: November 2012

Abstract

Background
This study aimed to explore and quantify the selection process to guide the decision on closure type (myocutaneous flap repair (MFR) or primary closure) for people undergoing pelvic exenteration.

Methods
This was a retrospective analysis of a prospectively maintained database with review of hospital records for verification and capture of missing data. Associations between four risk factors (previous radiotherapy, previous abdominoperineal resection, need for total exenteration, need for sacrectomy) were assessed individually and collectively as predictors of closure type and wound complications.

Results
A total of 203 pelvic exenteration procedures were reviewed (75 primary and 122 recurrent cancers). Thirty-nine patients (19·2 per cent) had MFR and 164 (80·8 per cent) primary closure. Patients who had MFR were significantly more likely to exhibit each risk factor, confirming the selective decision process. MFR had higher rates of complications across all four risk factors, individually and combined. In the primary closure group, there was a significant correlation between the number of risk factors and the proportion of patients with a complication (r = 0·25, P = 0·008). In contrast, no such relationship was found for the MFR group (r = 0·01, P = 0·973). Among patients who had any complication, the primary closure group had significantly lower rates of any wound dehiscence (15 of 64 versus 17 of 28; P &lt; 0·001) and total infection (16 of 64 versus 14 of 28; P = 0·019) compared with the MFR group.

Conclusion
Rates of wound and septic complications after pelvic exenteration were low in patients with fewer than two risk factors who had a primary closure. MFR had significantly higher complication rates, and should be reserved for patients with two or more risk factors or extensive skin involvement.
Randomized clinical trial of single-port, minilaparoscopic and conventional laparoscopic cholecystectomy
Authors: Saad S , Strassel V , Sauerland S 
Published: November 2012

Abstract

Background
This three-armed randomized clinical trial, with blinding of patients and outcome assessors, tested the hypothesis that single-port (SP) and/or minilaparoscopic (ML) cholecystectomy are superior to conventional laparoscopic (CL) cholecystectomy.

Methods
Patients eligible for elective laparoscopic cholecystectomy were randomized to SP, ML or CL procedures. The primary outcome was pain measured on a visual analogue scale twice daily during the blinded period. Secondary outcomes included duration of operation, technical performance score, complications, quality of life, cosmesis and patient satisfaction. Postoperative follow-up lasted 1 year.

Results
A total of 105 patients were randomized, 35 in each group. One conversion from a SP to a CL technique was necessary in a patient with chronic cholecystitis. Pain intensity was similar in the three groups, both during the blinded period (day 0 to 3; P = 0·865) and over the whole 7-day evaluation period (P = 0·911). The presence of clinically relevant between-group differences was ruled out (95 per cent confidence interval + 1·0 to − 0·5 for difference in pain scores between SP and CL groups, and − 0·8 to + 0·6 between ML and CL groups). Operating time was significantly longer for SP and ML than for CL cholecystectomy (P = 0·001). Postoperative complications included injury to the diaphragm (1), choledocholithiasis (1), wound infection (5) and hernia (1), all after SP cholecystectomy (P = 0·001). Twelve-month follow-up was complete in 99 patients (94·3 per cent). Cosmesis as rated by patients was significantly better at 6 months after SP and ML procedures (P = 0·043), but no difference was observed at 12 months (P = 0·229).

Conclusion
SP and ML cholecystectomy had no advantage over the CL approach in terms of postoperative outcome. Registration number: DRKS00000302 (German Registry of Clinical Trials).
Transanal endoscopic microsurgery approach for rectal stump resection as an alternative to transperitoneal stump resection
Authors: Bremers A J , van Laarhoven K J , van der Kolk B M , de Wilt J H , van Goor H 
Published: November 2012

Abstract

Background
Transperitoneal rectal stump resection is a complicated procedure with risk of inadvertent bowel, vascular and nerve injury. This study analysed the feasibility and safety of the use of transanal endoscopic microsurgery (TEM) to excise rectal stumps that would otherwise require a combined transabdominal and perineal approach.

Methods
Rectal stump resection was performed by a transanal approach using TEM. Stumps were removed by complete rectal wall resection and intersphincteric resection of the anus, leaving the mesorectum in place.

Results
The study included nine patients with a rectal stump ranging in length from 8 to 20 cm after previous surgery for inflammatory bowel disease (6), Lynch syndrome (1), collagenous colitis (1) or anastomotic leakage (1). The median duration of operation was 161 (range 107–239) min. The median postoperative length of hospital stay was 5 (range 2–71) days. One patient required an additional small-incision laparotomy to remove a stump extending up to the promontory and another developed a postoperative abscess. There were no perioperative complications.

Conclusion
TEM appeared to be a useful and safe approach for close rectal dissection and removal of a rectal stump while avoiding an abdominal approach for pelvic dissection.
Can Phosphate‐Branched RNA Persist under Physiological Conditions?
Authors: Lönnberg Tuomas A. 
Published: November 2012

AbstractA 2′‐O‐methyl‐RNA oligonucleotide containing a single free 2′‐OH group flanking a branching phosphotriester linkage was prepared as a model for phosphate‐branched RNA by using an orthogonally protected dimeric phosphoramidite building block in solid‐phase synthesis. The strategy allows the synthesis of phosphate‐branched oligonucleotides, the three branches of which may be of any desired sequence. Hydrolytic reactions of the phosphotriester linkages in such oligonucleotides were studied at physiological pH in the presence (and absence) of various complementary oligonucleotides. The fully hybridized oligonucleotide model is an order of magnitude more stable than its single‐stranded counterpart, which, in turn, is an order of magnitude more stable than its trinucleoside phosphotriester core lacking any oligonucleotide arms. Furthermore, kinked structures obtained by hybridizing the phosphate‐branched oligonucleotide with partially complementary oligonucleotides are three to five times more stable than fully double‐stranded ones and only approximately three times less stable than the so‐called RNA X structure, which has been postulated to incorporate an RNA phosphotriester linkage. The results indicate that when the intrinsically unstable RNA phosphotriester linkage is embedded in an oligonucleotide of appropriate tertiary structure, its half‐life can be at least several hours.
Selective Hydroalkoxylation of 1‐Hexene with 1‐Propanol and 1‐Butanol over Zeolite Beta Catalyst
Authors: Radhakrishnan Sambhu , Thoelen Grete , Franken Joris , Degrève Jan , Kirschhock Christine E. A. , Martens Johan A. 
Published: November 2012

AbstractEtherification of 1‐hexene with 1‐propanol and 1‐butanol representative of bioalcohols was performed in a liquid‐phase continuous‐flow process over a fixed bed of zeolite beta catalyst. Contact time and reaction temperature were optimized to maximize conversion and limit deactivation. The catalyst was stable for at least 14 h on stream. In the conversion of 1‐hexene with 1‐propanol, zeolite beta catalyst showed over 90 % selectivity for 2‐propoxyhexane. In the conversion of 1‐hexene and 1‐butanol, 2‐butoxyhexane was selectively formed. Dialkyl ether from the alcohol and dodecenes and hexanol from 1‐hexene were the main side products. As 1‐alkenes and terminal alcohols can be synthesized from biomass, this hydroalkoxylation process could be used for grading up green chemicals to high‐boiling solvents and renewable ethers for the diesel pool.
Functionalization of Mesoporous MCM‐41 (Nano)particles: Preparation Methodologies, Role on Catalytic Features, and Dispersion Within Polyethylene Nanocomposites
Authors: Bento A. , Lourenço J. P. , Fernandes A. , Cerrada M. L. , Rosário Ribeiro M. 
Published: November 2012

AbstractMCM‐41 micro‐ and nanoparticles are prepared and functionalized with silane coupling agents. These pristine and silane‐decorated mesoporous MCM‐41s are further used in the synthesis of MCM‐41/ethylene nanocomposites by in situ polymerization, utilizing either supported or non‐supported catalytic systems. The catalytic behavior of those systems is discussed, taking into consideration the effects of the particle size, surface characteristics, and functionalization. The results have shown that the initial surface state of MCM‐41 is of paramount importance to achieve high catalytic activity if a polymerization catalyst is to be supported. Functionalization changes the surface chemistry, thus, a positive or negative effect may be observed, depending on the previous features of the surface. The particle size of MCM‐41 and its functionalization affect its final dispersion within the polymeric matrix, this distribution is evaluated by SEM, TEM, and microhardness measurements.
Analysis of Potential Molecular Catalysts for the Hydroamination of Ethylene with Ammonia: A DFT Study with [Ir(PCP)] and [Ir(PSiP)] Complexes
Authors: Uhe Andreas , Hölscher Markus , Leitner Walter 
Published: November 2012

AbstractVery few cases of oxidative addition of NH3 to transition‐metal complexes forming terminal amide hydrides have been experimentally observed. Here, two examples with the iridium pincer complexes [Ir(PCP)(NH3)] A1 with PCP=[κ3‐(tBu2P‐C2H4)2CH]− and [Ir(PSiP)(NH3)] B1 with PSiP=[κ3‐(2‐Cy2P‐C6H4)2SiMe]− were investigated by DFT calculations applying the M06L density functional to successfully reproduce the trend of the experimentally observed thermochemical stabilities. According to the calculations, the corresponding hydrido‐amido complexes A2 and B2 are more stable than the corresponding ammine complexes by ΔG=−2.8 and −2.6 kcal mol−1, respectively. Complexes such as A2 and B2 are ideally suited entry points to catalytic cycles for the hydroamination of ethylene with ammonia. Therefore, the relevant stationary points of the potentially available cycles were studied computationally to verify if these complexes can catalyze the hydroamination. As a result, complex A2 will clearly not catalyze the hydroamination as all energy spans calculated range close to 40 kcal mol−1 or higher. The energy spans obtained with B2 are significantly lower in some cases and range around 35 kcal mol−1, further indicating that no turnover can be expected. By systematically varying the structure of B2, the energy span could be reduced to 28.8 kcal mol−1 corresponding to a TOF of 17 h−1 at a reaction temperature of 140 °C. A reoptimization of relevant structures under the inclusion of cyclohexane as a typical solvent reduces the calculated TOF to 6.0 h−1.
One‐Step Synthesis of Racemic α‐Amino Acids from Aldehydes, Amine Components, and Gaseous CO2 by the Aid of a Bismetal Reagent
Authors: Mita Tsuyoshi , Higuchi Yuki , Sato Yoshihiro 
Published: November 2012

Abstractα‐Amino acids are essential resources for human life and are highly useful as building blocks for organic synthesis. The core framework of an α‐amino acid can be divided into three basic components: an aldehyde, an amine, and carbon dioxide (CO2). We report herein that a one‐step synthesis of α‐amino acids has been successfully achieved from these three basic and inexpensive chemicals with a single operation, in which the mixture of an aldehyde, a sulfonamide, and gaseous CO2 was heated at 100 °C in the presence of Bu3Sn‐SnBu3 and CsF. In this one‐pot sequential protocol, two important intermediates (imine and α‐amino stannane) are involved and the stannyl anion generated in situ plays a crucial role, particularly for the efficient stannylation of the imine in the presence of proton sources and for promoting retrostannylation of the undesired α‐alkoxy stannane owing to its high stability and tolerance of the presence of proton sources. This methodology enabled the synthesis of a wide range of racemic arylglycine derivatives in high yields.
Small Changes Have Consequences: Lessons from Tetrabenzyltitanium and ‐zirconium Surface Organometallic Chemistry
Authors: Popoff Nicolas , Espinas Jeff , Pelletier Jérémie , Macqueron Benoît , Szeto Kai C. , Boyron Olivier , Boisson Christophe , Del Rosal Iker , Maron Laurent , De Mallmann Aimery , Gauvin Régis M. , Taoufik Mostafa 
Published: November 2012

AbstractHomoleptic benzyl derivatives of titanium and zirconium have been grafted onto silica that was dehydroxylated at 200 and 700 °C, thereby affording bi‐grafted and mono‐grafted single‐site species, respectively, as shown by a combination of experimental techniques (IR, MAS NMR, EXAFS, and elemental analysis) and theoretical calculations. Marked differences between these compounds and their neopentyl analogues are discussed and rationalized by using DFT. These differences were assigned to the selectivity of the grafting process, which, depending on the structure of the molecular precursors, led to different outcomes in terms of the mono‐ versus bi‐grafted species for the same surface concentration of silanol species. The benzylzirconium derivatives were active towards ethylene polymerization in the absence of an activator and the bi‐grafted species displayed higher activity than their mono‐grafted analogues. In contrast, the benzyltitanium and neopentylzirconium counterparts were not active under similar reaction conditions.
Investigation of the Time Response of a Fluidized Bed with Inductive Heating and the Influencing Variables
Authors: Stresing Antje , Mörl Lothar , Khaidurova Aleksandra , Jacob Michael , Walther Klaus 
Published: November 2012

AbstractMit einer neuen Methode wird berührungslos Energie in eine fluidisierte Schüttung eingebracht. Mithilfe eines elektromagnetischen Feldes wird eine Leistung auf elektrisch leitfähige Inertpartikel übertragen. Diese Methode zeichnet sich durch eine hohe Energiedichte und kurze Aufheizzeiten sowie einen guten Wirkungsgrad aus. In der Metallindustrie kann in vielen Bereichen auf diese Technologie nicht mehr verzichtet werden. Die experimentellen Ergebnisse zeigen, dass sich die Vorteile der Induktion auch für Anwendungen in Wirbelschichten nutzen lassen. Der Fokus der Untersuchung ist die Bestimmung des Zeitverhaltens und der Einflussgrößen, die diesen Prozess bestimmen.
Surveillance after resection for colorectal cancer
Authors: Brawarsky Phyllis , Neville Bridget A. , Fitzmaurice Garrett M. , Earle Craig , Haas Jennifer S. 
Published: November 2012

AbstractBACKGROUND:Professional societies recommend posttreatment surveillance for colorectal cancer (CRC) survivors. This study describes the use of surveillance over time, with a particular focus on racial/ethnic disparities, and also examines the role of area characteristics, such as capacity for CRC screening, on surveillance.METHODS:Surveillance, Epidemiology, and End Results (SEER)‐Medicare data were used to identify individuals aged 66 to 85 years who were diagnosed with CRC from 1993 to 2005 and treated with surgery. The study examined factors associated with subsequent receipt of a colonoscopy, carcinoembryonic antigen (CEA) testing, primary care (PC) visits, and a composite measure of overall surveillance.RESULTS:Of eligible subjects, 61.0% had a colonoscopy, 68.0% had CEA testing, 77.1% had PC visits, and 43.0% received overall surveillance. After adjustment, blacks were less likely than whites to undergo colonoscopy (odds ratio [OR] 0.76, 95% confidence interval [CI] = 0.69‐0.83) and to receive CEA testing and overall surveillance, whereas white/Hispanic rates did not differ. Rates for all outcomes increased from 1993 to 2005, but black/white disparities remained. Individuals in areas with greatest capacity for CRC screening were more likely (OR = 1.09, 95% CI = 1.02‐1.18) to receive colonoscopy, and those in areas with the greatest percentage of blacks were less likely (OR = 0.89, 95% CI = 0.83‐0.95) to receive colonoscopy. Those living in areas with shortage of PC were less likely to receive PC visits (OR = 0.55, 95% CI = 0.48‐0.64) and overall surveillance (OR = 0.83, 95% CI = 0.71‐0.98).CONCLUSIONS:Many CRC survivors do not get recommended surveillance, and black/white disparities in rates of surveillance have not improved. Characteristics of the area where an individual lives contribute to the use of surveillance. Cancer 2013. © 2012 American Cancer Society.
Identification of distinct tyraminergic and octopaminergic neurons innervating the central complex of the desert locust, Schistocerca gregaria
Authors: Homberg Uwe , Seyfarth Jutta , Binkle Ulrike , Monastirioti Maria , Alkema Mark J. 
Published: November 2012

AbstractThe central complex is a group of modular neuropils in the insect brain with a key role in visual memory, spatial orientation, and motor control. In desert locusts the neurochemical organization of the central complex has been investigated in detail, including the distribution of dopamine‐, serotonin‐, and histamine‐immunoreactive neurons. In the present study we identified neurons immunoreactive with antisera against octopamine, tyramine, and the enzymes required for their synthesis, tyrosine decarboxylase (TDC) and tyramine β‐hydroxylase (TBH). Octopamine‐ and tyramine immunostaining in the central complex differed strikingly. In each brain hemisphere tyramine immunostaining was found in four neurons innervating the noduli, 12–15 tangential neurons of the protocerebral bridge, and about 17 neurons that supplied the anterior lip region and parts of the central body. In contrast, octopamine immunostaining was present in two bilateral pairs of ascending fibers innervating the upper division of the central body and a single pair of neurons with somata near the esophageal foramen that gave rise to arborizations in the protocerebral bridge. Immunostaining for TDC, the enzyme converting tyrosine to tyramine, combined the patterns seen with the tyramine‐ and octopamine antisera. Immunostaining for TBH, the enzyme converting tyramine to octopamine, in contrast, was strikingly similar to octopamine immunolabeling. We conclude that tyramine and octopamine act as neurotransmitters/modulators in distinct sets of neurons of the locust central complex with TBH likely being the rate‐limiting enzyme for octopamine synthesis in a small subpopulation of TDC‐containing neurons. J. Comp. Neurol. 521:2025–2041, 2013. © 2012 Wiley Periodicals, Inc.