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For a chemical signal to propagate across a cell, it must navigate a tortuous environment involving a variety of organelle barriers. In this work we study mathematical models for a basic chemical signal, the arrival times at the nuclear membrane of proteins that are activated at the cell membrane and diffuse throughout the cytosol. Organelle surfaces within human B cells are reconstructed from soft X-ray tomographic images, and modeled as reflecting barriers to the molecules' diffusion. We show that signal inactivation sharpens signals, reducing variability in the arrival time at the nuclear membrane. Inactivation can also compensate for an observed slowdown in signal propagation induced by the presence of organelle barriers, leading to arrival times at the nuclear membrane that are comparable to models in which the cytosol is treated as an open, empty region. In the limit of strong signal inactivation this is achieved by filtering out molecules that traverse non-geodesic paths.

Cortical spreading depression (SD) is a spreading disruption of ionic homeostasis in the brain during which neurons experience complete and prolonged depolarizations. SD is the basis of migraine aura and is increasingly associated with many other brain pathologies. Here, we study the role of glutamate and NMDA receptor dynamics in the context of an ionic electrodiffusion model. We perform simulations in one (1D) and two (2D) spatial dimension. Our 1D simulations reproduce the "inverted saddle" shape of the extracellular voltage signal for the first time. Our simulations suggest that SD propagation depends on two overlapping mechanisms; one dependent on extracellular glutamate diffusion and NMDA receptors and the other dependent on extracellular potassium diffusion and persistent sodium channel conductance. In 2D simulations, we study the dynamics of spiral waves. We study the properties of the spiral waves in relation to the planar 1D wave, and also compute the energy expenditure associated with the recurrent SD spirals.

With advances of combined modality therapy, prognoses in esophageal cancer have been improving. After resection of esophageal cancer, the development of gastric tube cancer is a risk. While such cancer in an early stage can be cured endoscopically, total gastric tube resection is indicated in advanced stages. A 68-year-old man underwent subtotal esophagectomy reconstructed with a gastric tube through the retrosternal route. Gastric cancer was found one and a half years postoperatively. The gastric tube was resected without sternotomy. This is the first report of a patient undergoing resection of the gastric tube reconstructed through the retrosternal route without sternotomy.

Abstract We believe that our report and further case reports on T‐cell chronic lymphocytic leukemia with genetic profile will contribute to the molecular classification of this rare but distinct disease.

Background: Bronchiolitis obliterans syndrome (BOS) is the term used for the progressive obliteration of small airways before the patient has had a confirmatory lung biopsy. It is also recognized as a transplant-related complication. There have been no reports of BOS during initial standard chemotherapy. Case presentation: A 50-year-old woman with newly diagnosed follicular lymphoma grade 2, stage 3A, presented with hypoxia and progressive dyspnoea after the fifth cycle of R-CHOP. High-resolution computed tomography showed air trapping enhanced at the end-expiratory phase. Pulmonary function testing revealed severe obstructive and restrictive failure without bronchodilator response. We diagnosed BOS based on current criteria and treated the patient with glucocorticoids and cyclosporin. She was discharged home on oxygen therapy. However, soon after discharge, her respiratory symptoms deteriorated and she was hospitalized in a palliative care unit. She died of respiratory failure within a year of symptom onset. Conclusions: This is the first case report to describe rapidly progressive BOS in a patient undergoing R-CHOP treatment, which strongly suggests the condition was caused by the chemotherapy. Although a pathological diagnosis was not obtained, the clinical diagnosis of BOS was important so that the patient could receive appropriate treatment and palliative care based on the prognosis of this incurable condition.