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Two surface-anchored aluminum(III) porphyrin (AlPorF[Formula: see text] stacks, AlPorF3(Py)-COO/TiO2 and AlPorF3(Ph)-COO/TiO2, have been constructed to investigate the interfacial electron injection from the AlPorF3 into the conduction band of the TiO2 nanoparticles as a function of stacking topology. The Lewis acid properties of AlPorF3 were combined with the electronic and surface properties of TiO2 to obtain the investigated porphyrin stacks. The axial Lewis base, pyridyl (Py) unit, in AlPorF3(Py)-COO/TiO2 directs the porphyrins to stack on the TiO2 surface in a layered fashion. The absence of a Lewis base in AlPorF3(Ph)-COO/TiO2 is unable to form such defined stacks. The AlPorF3(Py)-COO/TiO2 and AlPorF3(Ph)-COO/TiO2 were characterized by steady-state and transient spectroscopic techniques. Transient absorption spectral studies show that surface-stacked hybrids exhibit electron injection from AlPorF3 to the conduction band of TiO2. However, the injection efficiencies and kinetics are not very different in the investigated stacks AlPorF3(Py)-COO/TiO2 and AlPorF3(Ph)-COO/TiO2 indicating that the axial self-assembly does not alter the electronic communication within the AlPorF3 layer to a significant level to perturb the photodynamics.

Early experience with a novel multielectrode saline-irrigated radiofrequency balloon (RFB) catheter with an integrated camera system found that it was safe and effective in performing single-shot pulmonary vein isolation (PVI) for atrial fibrillation.The purpose of this study was to further assess potential treatment risks by looking for subclinical events.The study was performed at 2 sites. Patients underwent PVI by RFB. A control group underwent conventional point-by-point radiofrequency ablation. Stroke scale questionnaire and brain magnetic resonance imaging (MRI) were performed before and after the ablation procedure, and esophageal endoscopy was performed after the procedure in RFB patients only.We enrolled 27 patients in the RFB group and 15 patients in the control group. The RFB and control groups were well matched [predominantly male: 62% vs 53%; CHAAn increased rate of clinically silent cerebral events was seen in the RFB group. A low rate of esophageal thermal injury was observed.

BACKGROUND AND AIM Our aim was to evaluate the efficacy and safety of a lumen-apposing metal stent with an electrocautery-enhanced delivery system (EDS-LAMS) for endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) in regular clinical practice. METHODS A retrospective and subsequent prospective analysis was undertaken of all patients who underwent EUS-guided drainage of their PFCs using the EDS-LAMS at 17 tertiary therapeutic endoscopy centers. RESULTS Two hundred eight cases of EDS-LAMS deployment were attempted in 202 patients (mean age 52.9 years) at time of evaluation. Ninety-seven patients had pancreatic pseudocysts (PPs), 75 walled-off pancreatic necrosis (WOPN), 10 acute peripancreatic fluid collections (APFCs), 6 acute necrotic collections (ANCs), and 14 postoperative collections (POCs). Procedural technical success was achieved in 202/208 cases (97.1%). Maldeployment occurred in 7/208 cases (3.4%). Clinical success was achieved in 142/160 (88.8%) patients (PP 90%, WOPN 85.2%, APFC 100%, ANC 75%, POC 100%). Delayed adverse events included stent migration in 15/202 (7.4%), stent occlusion and infection in 16/202 (7.9%), major bleeding in 4/202 (2%), and buried EDS-LAMS in 2/202 (1%). PFC recurrence occurred in 13/142 (9.2%) patients; 9/202 (4.5%) required surgical or radiological intervention for PFC management after EDS-LAMS insertion. CONCLUSIONS This large international multicenter study evaluating the EDS-LAMS for drainage of PFCs in routine clinical practice suggests that the EDS-LAMS are safe and effective for drainage of all types of PFCs; however, further endoscopic therapy is often required for WOPN. Major bleeding was a rare complication in our cohort.

Background: Catheter ablation for atrial fibrillation has potential to cause esophageal thermal injury. Esophageal temperature monitoring during ablation is commonly used; however, it has not eliminated thermal injuries, possibly because conventional sensors have poor spatial sampling and response characteristics. To enhance understanding of temperature dynamics that may underlie esophageal injury, we tested a high-resolution, intrabody, infrared thermography catheter to continuously image esophageal temperatures during ablation. Methods and Results: Atrial fibrillation ablation patients were instrumented with a flexible, 9F infrared temperature catheter inserted nasally (n=8) or orally (n=8) into the esophagus adjacent to the left atrium. Ablation was performed while the infrared catheter continuously recorded surface temperatures from 7680 points per second circumferentially over a 6-cm length of esophagus. Physicians were blinded to temperature data. Endoscopy was performed within 24 hours to document esophageal injury. Thermal imaging showed that most patients (10/16) experienced ≥1 events where peak esophageal temperature was >40°C. Three patients experienced temperatures >50°C; and 1 experienced >60°C. Analysis of temperature data for each subject’s maximum thermal event revealed high gradients (2.3±1.4°C/mm) and rates of change (1.5±1.3°C/s) with an average length of esophageal involvement of 11.0±5.4 mm. Endoscopy identified 3 distinct thermal lesions, all in patients with temperatures >50°C; all resolved within 2 weeks. Conclusions: Infrared thermography provided dynamic, high-resolution mapping of esophageal temperatures during cardiac ablation. Esophageal thermal injury occurred with temperatures >50°C and was associated with large spatiotemporal gradients. Additional studies are warranted to determine the relationships between thermal parameters and esophageal injury.

Background Whether early Barrett's neoplasia has a predilection for particular spatial locations in shorter segment disease is currently unknown. Anatomic factors may play a role in lesion location because of differing levels of mucosal acid exposure. Objective To identify high-risk lesion locations, which has important implications for surveillance strategies. Design We interrogated a prospectively maintained database of patients who underwent endoscopic resection (ER) for Barrett's neoplasia at 2 Australian tertiary centers. Lesions targeted for ER were characterized and their location in the distal esophagus was noted as on a clock face. A Z test of proportions was used to test for deviation from uniformity in the distribution of lesions. Setting Two Australian tertiary centers. Patients Patients who underwent ER for Barrett's neoplasia. Main Outcome Measurements Lesion location in the distal oesophagus, resected specimen histology. Results A total of 146 consecutive patients had ER for biopsy-proven high-grade dysplasia or esophageal adenocarcinoma. A total of 75 patients had Barrett's segment length of 5 cm or less and a visible lesion. Five patients had 2 visible lesions giving a total of 80 lesions. ER of 66 lesions (82.5%) led to the identification of advanced pathology: 37 high-grade dysplasia (46%), 24 mucosal adenocarcinoma (30%), 5 submucosal adenocarcinoma (6%). Of a total of 80 lesions, 43 (53.8%) (95% CI, 42.9%-64.7%) were centered within the 2- to 5-o'clock arc, comprising 25% of the circumference. This area also accounted for 36 (54.5%) of the 66 lesions with advanced histology (95% CI, 42.5%-66.5%). All confidence intervals lie wholly above the 25% expected in a uniform circular distribution ( P Limitations Observational study in a tertiary center. Conclusions In Barrett's maximal segments of 5 cm or less, the 2- to 5-o'clock arc, accounts for approximately 50% of macroscopically visible lesions and associated early neoplasia. This finding has important implications for surveillance strategies.

Background and study aims: Complete Barrett’s excision (CBE) of short-segment Barrett’s high grade dysplasia (HGD) and early esophageal adenocarcinoma by stepwise endoscopic resection is a precise staging tool, detects covert synchronous disease, and may produce a sustained treatment response. Esophageal stricture is the most commonly reported complication of CBE although risk factors have not yet been clearly defined. Patients and methods: Data were recorded prospectively on patients with limited co-morbidity and age ≤ 80 years undergoing CBE for histologically proven HGD or esophageal adenocarcinoma within ≤ C3M5 segments. Endoscopic resection was performed by standardized protocol every 6 – 8 weeks until CBE was achieved. Esophageal dilation was performed when patients reported dysphagia. Dysphagia scores were recorded at scheduled endoscopic surveillance or by telephone interview. Results: By intention-to-treat analysis, complete eradication of neoplasia and intestinal metaplasia was achieved in 95 % and 82 %, respectively, in 77 patients undergoing a median of 2 resection sessions (interquartile range [IQR] 1 – 3). Esophageal dilation was required in 33 % (median 3 dilations, IQR 1 – 3.5) at median follow-up of 20 months (IQR 6 – 40). Independent risk factors for dilation requirement were the number of mucosal resections at the index procedure (odds ratio [OR] 1.3 per resection, 95 % confidence interval [CI] 1.0 – 1.9; P = 0.043) and maximal extent of the Barrett’s segment (OR 2.2 per cm, 95 %CI 1.2 – 3.9; P = 0.009). Conclusions: Although CBE is highly effective in the treatment of Barrett’s HGD and esophageal adenocarcinoma, the risk of post-CBE dysphagia increases with the maximal extent of the Barrett’s segment and the number of mucosal resections at the index procedure. These data could be used to inform treatment decisions and identify those patients who may benefit from prophylactic therapies such as dilation.

This essay examines the relationship between Bevis and his horse, Arondel, in the Middle English Bevis of Hampton. In the romance, all the key characters attempt to gift or obtain Arondel to demonstrate their largesse as rulers or gain prestige from possessing the remarkable horse. In this respect, the romance depicts horses as an important form of social currency in lord–vassal relations. However, Arondel cannot be easily circulated within the gift economy of feudal relations because he resists objectification. Acknowledging Arondel's agency, Bevis himself treats the horse more as a feudal subject than an exchangeable possession and their relationship dramatizes how fealty and vassalage can cross species lines. While anthropocentric in many respects, their relationship does not confine human-horse interaction to animal subservience for human benefit. Instead, Bevis suffers and sacrifices on Arondel's behalf, ultimately forfeiting a leading place in the English aristocracy and his ancestral lands to save Arondel's life. Through these acts of loyalty and reciprocity, Bevis and Arondel illustrate the possibilities for inter-species communication without suggesting that the gulf between man and horse can be definitively bridged.

In his entry on fathers in De Proprietatibus Rerum (ca. 1240), Bartholomaeus Anglicus writes: “He loves most the son that is most like him and often observes and watches over him. He gives his children clothing and food and drink appropriate to their age. He purchases land and provides an inheritance for his children, and makes sure it increases. He tills the land and leaves it to his heirs.”1 Moving away from the more abstract scientific discourse on the father’s role in procreation that begins the entry, which he attributes to constantine and Aristotle, Bartholomaeus grounds his depiction of fatherhood in affect, provision, and inheritance. At the same time, he observes that a father’s actions are guided by the order of his children’s birth and how much they appear to resemble him. These themes are taken up again toward the end of the entry

Extended scenes of loss and mourning are key innovations in John Gower's “Tale of Apollonius of Tyre.” Judith Butler's ideas concerning loss and identity illuminate the ways in which loss and its commemoration constitute the family by suggesting certain modes of grief are recognizable and certain losses are mournable by society. The problematic response to loss is shown in Antiochus's incest, in which traces of grief are coded in his gnomic riddle. While loss unhinges masculine identities, as evinced in Antiochus's incest and Apollonius's initial reaction to his wife's death at sea, the tale also shows how properly socialized loss restores a measure of patriarchal authority. The constitutive power of rituals commemorating loss creates a virtual family when none is present, and this version of the family confers political and social authority on Apollonius. At the same time, the vulnerability that Apollonius experiences in loss forms the basis for a community of grief that joins a ruler with his pe...

This article argues that the Troilus’s relationship with Criseyde is fraught with anxious desire. By referencing medieval theories of the mind and Kleinian psychoanalytic theory, it shows that the manner in which Troilus memorializes his desire for Criseyde in the books I to III of the poem has a direct impact on the way he experiences her loss in book V. Throughout the poem, anxiety is the definitive characteristic of Troilus’s desire. It emerges when he first encounters an uncontrollable desire and when the consummation of his desire is delayed. It is this anxious engendering of desire, and not loss per se, that causes the feelings of persecution and victimization in Troilus when he loses Criseyde at the end of the poem.

Esophageal thermal injury commonly occurs during radiofrequency ablation (RFA) of atrial fibrillation and may rarely lead to atrioesophageal fistula. We present an esophageal thermal image using a novel infrared thermography system that provides fast, contact-independent, thermal mapping over the full circumference of a 6-cm length of the esophagus. During this first-in-man evaluation, the physician was blinded to the infrared temperature data. A 9-F infrared thermography catheter (Securus Medical Group, Inc., Cleveland, OH) was inserted via the oropharynx into the esophagus, posterior to the left atrium. Temperature was continuously recorded with 1-mm spatial resolution along the catheter axis at 3800 samples/s over a 3601 by 60mm length of the esophagus (see the Online Supplement for further details). Figure 1A shows the esophageal temperature pattern at an instant when peak temperature (Tpeak) was 47.21C during posterior wall RFA at 20 W using a 4-mm irrigated tip ablation catheter (NaviStar ThermoCool, Biosense Webster Inc., Diamond Bar, CA). In Figure 1B, esophageal Tpeak is plotted over a period from 9:46 to 9:50 AM with a maximum Tpeak of 57.11C. The time of the thermal map in Figure 1A is indicated by the star on Figure 1B. The patient was a 31-year-old male with persistent atrial fibrillation and an atrial septal defect awaiting repair who underwent RFA pulmonary vein isolation under general anesthesia. During the procedure, we observed 6 thermal excursions where local esophageal Tpeak was 431C above the core body temperature. We observed that thermal excursions were generally elliptical (Figure 1 and Online Video) with a maximum length of 13 mm along the esophageal catheter axis, with large temperature gradients

Studies have suggested that a colonoscopy withdrawal time of at least 6 minutes is associated with an increased adenoma detection rate in patients undergoing colorectal cancer screening.We aimed to determine colonoscopy withdrawal time and rate of polyp detection in a blinded study--conducted at Christchurch Hospital (Christchurch, New Zealand)--to determine if there was a relationship.All 16 consultant endoscopists performing colonoscopy in a tertiary hospital had their withdrawal time from the caecum prospectively timed over 208 consecutive procedures between 11 April 2007 and 19 May 2007. The following data was collected: indication for procedure, final diagnosis, polypectomy rate, procedures performed and withdrawal time were recorded. Histology results were reviewed for all patients.111 (53%) of colonoscopies were performed for symptom assessment and 97 (47%) for surveillance. There was significant heterogeneity between colonoscopists' withdrawal times (p0.001). Polyps were diagnosed in 65 of all colonoscopies (31.3%). Of the screening colonoscopies polyps were found in 38 (39.1%) of which 14 were adenomas (adenoma detection rate of 14%). The median colonoscopy withdrawal time was 3 minutes 16 seconds when no polyps were found (range 5 seconds to 11 minutes 50 seconds). The median colonoscopy time when polyps were found was 8 minutes 31 seconds which included time taken for procedures (range 2 minutes 7 seconds to 35 minutes 40 seconds), p0.001.This study confirms that more adenomas were found by those endoscopists who had slower withdrawal times. Also colonoscopy withdrawal times are inherently much faster than recommended and highlights the importance of regular adenoma detection rate and withdrawal time auditing.

The preparation by total synthesis of a new class of β-lactam antibiotics is reported. Conversion of alcohol 1b to its mesylate 9b followed by hydrolysis of the acetal to the enol 1b and base-catalyzed ring closure gave benzyl 7- β-azido-Δ3-O-2-isocephem-4-carboxylate 8b. Similarly prepared were the 3 -methyl, 3 -benzyl, and 3 -phenethyl analogs (32b–d). Reduction of the azides followed by coupling of the resultant amines with phenoxyacetic acid and removal of the benzyl groups by hydrogenolysis gave the acids 35a–e which exhibited high antibacterial activity. The structural assignments to the O-2-isocephems which were made on the basis of their spectral characteristics (ir, uv, and nmr) are discussed.

Treatment of the acid 3 with triethylamine in refluxing tert-butyl alcohol gave the decarboxylated product 4 which was isomerized to the desired Δ3 isomer 5 using DBN. Reduction of the azido functions in 4 and 5 followed by coupling to phenoxyacetic acid and debenzylation gave the acids 11 and 8, respectively. Attempts to prepare dienic cephalosporins failed. The halogenation of 4 and 5 was studied and is discussed.

The syntheses of the desthiocephem system from the enol 2 is described. Thus conversion of 2 to its triflate 3 followed by treatment with the sodium salts of malonate esters gave the cyclized products 4a–c. Azide reduction followed by coupling of phenoxyacetic acid and hydrogenolysis gave the acids 7 and 8. Compound 15 was also prepared.

The general synthetic scheme to nuclear analogs of cephalosporins described in previous papers of this series is reviewed and the synthesis of a series of sidechain derivatives is given. Thus, systems of the following type were formed: carbacephems (A), 2-isocephems (B), N-2-isocephems (C), and O-2-isocephems (D). The invitro microbiological activity of these compounds (with appropriate side-chains attached) is given, with comparison to analogous cephalosporins. Systems of type A, B, and C were only prepared with a 3-H or CH3 substituent and had modest antibacterial activity. The O-2-isocephems (D) were prepared with a wide variety of sidechains at 3 and 7 and were found to have biological activity quite comparable to the cephalosporins. A more detailed biological examination (both invitro and invivo) of the O-2-isocephem analog (19i) of cephalothin was made.

The synthesis of 7β-(-2′-thienylacetamido)-3-acetoxymethyl-Δ3-O-2-isocepheni-4-carboxylic acid (17) is described. Thus treatment of enol mesylate 3a or triflate 3b with triethylamine gave the allene 4 which gave the diiodide upon treatment with iodine. The diiodide gave benzyl 7β-azido-3-acetoxymethyl-Δ3-O-2-isocephem-4-carboxylate (12) on treatment with potassium acetate in DMF. Hydrogenolysis of 12 gave the amino acid 16 which was converted to 17 upon treatment with 2-thienylacetyl chloride. Resolution of 17 into its optical antipodes was carried out. The antibiotic activities of racemic 17 and each antipode is compared to that of cephalothin. Antibiotic activity was found to reside in the dextrorotatory isomer.

The general synthetic scheme to nuclear analogs of cephalosporins described in previous papers of this series is reviewed and the synthesis of a series of sidechain derivatives is given. Thus, syst...

The preparation by total synthesis of a new class of β-lactam antibiotics is reported. Conversion of alcohol 1b to its mesylate 9b followed by hydrolysis of the acetal to the enol 1b and base-catal...

Aus dem Enolazid (I) und dem Anhydrid (II) wird das Triflat bicyclooctenaziden (V) cyclisiert.