Transpacific American Literature: Curriculum, Cartography, Crossover

This essay considers the complications involved in constructing and delivering a university course on Transpacific American Literature. It analyses these complexities in terms of the intertextual relationship between transpacific and transatlantic literature. It also examines ways in which various forms of cartography have shaped ways in which the subject has been formulated. By focusing on the specific exampleofMaxine Hong Kingston’s narratives, this essay suggests ways in which Southeast Asia operates as a fulcrum in her work for a reverse mapping of the subject, in relation to both space and time. In this sense, it argues that transpacific American literature sheds light on the constitution of the history and geography of American literature more broadly.

Preventing Breast Cancer-Related Lymphedema: Feasibility of Axillary Reverse Mapping Technique

Introduction. Our study aimed to determine the feasibility of axillary reverse mapping (ARM) technique, the identification rate of ARM nodes and their metastatic involvement, as well as to identify the factors that influence the identification and metastatic involvement. Material and methods. In total, 30 breast cancer patients scheduled for axillary lymph node dissection were enrolled in our study. The lymphatic nodes that drain the arm were identified by injecting 1 mL of blue dye in the ipsilateral upper arm; then, the ARM nodes were resected along with the other lymph nodes and sent for histological evaluation. Results. Identification of ARM node was successful in 18 patients (60%) and 22.22% of the identified ARM lymph nodes had metastatic involvement. Patients with identified ARM nodes had a significant lower BMI and a statistically significant relationship between axillary lymph node status and ARM node metastases was proven. Most of ARM lymph nodes (96.3%) were found above the intercostobrachial nerve, under the axillary vein and lateral to the thoracodorsal bundle. Conclusions. The ARM procedure is easy to reproduce but might not be appropriate for patients with a high BMI. The rate of metastatic involvement of ARM nodes is significant and no factor can predict it, showing that the preservation of these nodes cannot be considered.

Lipids in the Piezo1 channel pore: gating mechanism, or simulation artifact?

Opening and closure of certain mechanosensitive ion channels have recently been linked with the presence of lipids in or near their pores. Although non-conducting structures of mechanosensitive Piezo channels do not show the presence of lipids in the pore, computational simulations suggest whole phospholipids enter the Piezo1 pore in the closed state. Here, to probe this phenomenon, we conduct coarse-grained (CG) and all-atom (AA) simulations of Piezo1 with different solvation algorithms and equilibrium protocols, including CG-to-AA reverse mapping from Martini CG force field to CHARMM AA force field. Our results show that the lack of initial hydration of the upper pore region, enabled by common CG but not AA solvation algorithms, allows entry of whole lipids through gaps between pore helices during subsequent equilibrium simulations. Absolute binding free energy calculations show that these lipids are thermodynamically unfavorable, indicating they are likely kinetically trapped in the pore during microsecond-long AA simulations. An alternative equilibrium protocol is proposed to avoid such simulation artifact for channels whose pores are walled with transmembrane gaps. This work underscores the notion that, as simulated systems become increasingly complex, interpretation of simulated data in physiological contexts requires extra precautions. When no experimental data is available, free energy approaches such as those implemented here appear as trustworthy validations of results observed from MD trajectories.

Oncological Safety of Axillary Reverse Mapping in Patients With Clinically Node-Negative Breast Cancer

Background Axillary reverse mapping (ARM) was developed to preserve the lymphatic drainage from the upper arm during sentinel lymph node (SLN) biopsy or axillary lymph node dissection (ALND). However, the oncological safety of ARM has been controversial. Methods Patients with clinically negative nodes (cN0) underwent SLN biopsy and ARM. SLNs were identified using blue dye and radioisotope, and ARM nodes were traced using the fluorescent method. Patients with positive SLN underwent the standard ALND. After surgery, they were followed up for more than three years. Results A total of 507 patients with cN0 breast cancer were enrolled between May 2009 and November 2017. SLNs were identified in 499 (98%) of 507 patients, and ARM nodes were identified in 159 (31%) patients in the SLN field. The crossover rate of SLN-ARM nodes was 28%. Among 95 patients with positive SLNs, 70 patients underwent conventional ALND. ARM nodes were identified in 65 (93%) of those patients in the ALND field. The mean number of removed ARM nodes was 7.2 (range 0–25) in patients who underwent the standard ALND. Although ARM nodes were involved in 18 of 65 patients, the involved ARM nodes were the same SLNs identified in 14 (78%) patients. Since SLN-ARM nodes should be removed, ARM nodes were involved only in 4 (5.7 %) patients after SLN biopsy. Conclusions ARM nodes were not infrequently involved in patients with positive SLNs, but they were most often SLNs. Therefore, conservative ALND with ARM is oncologically acceptable in patients with positive SLN.