145 research outputs found

    Myelination and Isochronicity in Neural Networks

    Get PDF
    Our brain contains a multiplicity of neuronal networks. In many of these, information sent from presynaptic neurons travels through a variety of pathways of different distances, yet arrives at the postsynaptic cells at the same time. Such isochronicity is achieved either by changes in the conduction velocity of axons or by lengthening the axonal path to compensate for fast conduction. To regulate the conduction velocity, a change in the extent of myelination has recently been proposed in thalamocortical and other pathways. This is in addition to a change in the axonal diameter, a previously identified, more accepted mechanism. Thus, myelination is not a simple means of insulation or acceleration of impulse conduction, but it is rather an exquisite way of actively regulating the timing of communication among various neuronal connections with different length

    Curative two-stage resection for synchronous triple cancers of the esophagus, colon, and liver: Report of a case

    Get PDF
    AbstractIntroductionCases of synchronous triple cancers of the esophagus and other organs curatively resected are rare.Presentation of caseA 73-year-old man was admitted to our hospital with bloody feces. He was diagnosed with synchronous triple cancers of the esophagus, colon, and liver. We selected a two-stage operation to safely achieve curative resection for all three cancers. The first stage of the operation comprised a laparoscopy-assisted sigmoidectomy and partial liver resection via open surgery. The patient was discharged without complications. Thirty days later, he was readmitted and thoracoscopic esophagectomy was performed. Although pneumonia-induced pulmonary aspiration occurred as a postoperative complication, it was treated conservatively. The patient was discharged on postoperative day 24.DiscussionEsophagectomy is a highly invasive procedure; thus, simultaneous surgery for plural organs, including the esophagus, may induce life-threatening, severe complications. Two-stage surgery is useful in reducing surgical stress in high-risk patients. For synchronous multiple cancers, the planning of two-stage surgery should be considered for each cancer to maintain organ function and reduce the stress and difficulty of each stage.ConclusionWe successfully treated synchronous triple cancers, including esophageal cancer, by a two-stage operation

    Solitary Cardiac Metastasis of Hepatocellular Carcinoma

    Get PDF
    Cardiac metastasis originating from hepatocellular carcinoma (HCC) is a rare condition with a poor prognosis. No therapeutic standards for cardiac metastasis originating from HCC have been established. At 19 months after a curative hepatectomy, a 64-year-old Japanese hepatitis B virus-positive male patient experienced solitary cardiac metastasis originating from HCC. The cardiac tumor was discovered in the right ventricle. The patient received three courses of radiotherapy and chemotherapy and survived > 3 years after the initial diagnosis of cardiac metastasis. His case demonstrates that radiotherapy combined with chemotherapy can be an effective treatment for cardiac metastasis

    The Late Phase/Early Phase Ratio of Pancreatic CT Values as a Novel Predictor of Pancreatic Fistula after Distal Pancreatectomy

    Get PDF
    Post-operative pancreatic fistula (POPF) remains the most common complication after distal pancreatectomy (DP). In this retrospective study, we reviewed the data from patients who underwent DP between 2008 and 2019 in our institute to determine whether the late phase/early phase ratio (L/E ratio) by preoperative computed tomography (CT) scan in the pancreas could predict POPF occurrence after DP. We examined the relationship between preoperative or intraoperative factors and the occurrence of POPF after DP using statistical methods in 23 males and 21 females with a mean age of 73. The mean L/E ratio was significantly lower in the POPF group than the non-POPF group (p=0.035). The L/E ratio had moderate diagnostic accuracy, with a calculated optimal cutoff value of 0.77. In univariate analysis, a significant association was noted between POPF and stump thickness ≥ 16.9, body mass index ≥ 27.5, and L/E ratio ≤ 0.77. In the multivariate analysis, the L/E ratio (odds ratio, 5.96; p=0.036) was an independent risk factor for POPF. Our findings suggest that the pancreatic L/E ratio may predict the occurrence of POPF after DP. This measure may be useful in preoperative risk stratification, patient counseling, and perioperative patient management, improving clinical outcomes after DP

    Safety of Surgical Treatment for Elderly Patients with Gallbladder Carcinoma

    Get PDF
    Gallbladder carcinoma (GBC) is a common malignancy with a poor prognosis. With the average life expectancy increasing globally, the incidence of GBC is predicted to increase as well. We investigated the safety and feasibility of surgical treatment for elderly patients with GBC. We retrospectively compared clinical pathological data and treatment outcomes in 45 consecutive GBC patients (23 patients ≥ 75 years [elderly group] and 22 patients < 75 years [younger group]) who underwent curative resection at the Iwakuni Center from January 2008 to December 2017. The proportion of preoperative comorbidities and anticoagulant use was significantly higher in the elderly group. The American Society of Anesthesiologists score was higher in the elderly versus the younger group, and the elderly group had significantly shorter operation times. Reduced activities of daily living was more common in the elderly versus younger group. The percentage of radical resection and overall 3-year survival (66.6% younger vs. 64.4% elderly) were similar between the groups. Controlling Nutritional Status (CONUT) score ≥ 3 and R0 resection were identified as prognostic factors for overall survival rate among all patients. After careful patient selection

    Pulmonary intravascular lymphoma diagnosed by 18-fluorodeoxyglucose positron emission tomography-guided transbronchial lung biopsy in a man with long-term survival: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>18-Fluorodeoxyglucose positron emission tomography can detect the pulmonary involvement of intravascular lymphoma that presents no abnormality in a computed tomography scan.</p> <p>Case presentation</p> <p>We report the case of a 61-year-old Japanese man who had pulmonary intravascular lymphoma and no computed tomography abnormality. We were able to make an antemortem diagnosis of pulmonary intravascular lymphoma by transbronchial lung biopsy according to 18-fluorodeoxyglucose positron emission tomography findings. He is free of recurrent disease 24 months after chemotherapy.</p> <p>Conclusions</p> <p>To the best of our knowledge, this is the first reported case of a long-term survivor of pulmonary intravascular lymphoma diagnosed by transbronchial lung biopsy under the guide of 18-fluorodeoxyglucose positron emission tomography.</p

    Mathematical Identification of Critical Reactions in the Interlocked Feedback Model

    Get PDF
    Dynamic simulations are necessary for understanding the mechanism of how biochemical networks generate robust properties to environmental stresses or genetic changes. Sensitivity analysis allows the linking of robustness to network structure. However, it yields only local properties regarding a particular choice of plausible parameter values, because it is hard to know the exact parameter values in vivo. Global and firm results are needed that do not depend on particular parameter values. We propose mathematical analysis for robustness (MAR) that consists of the novel evolutionary search that explores all possible solution vectors of kinetic parameters satisfying the target dynamics and robustness analysis. New criteria, parameter spectrum width and the variability of solution vectors for parameters, are introduced to determine whether the search is exhaustive. In robustness analysis, in addition to single parameter sensitivity analysis, robustness to multiple parameter perturbation is defined. Combining the sensitivity analysis and the robustness analysis to multiple parameter perturbation enables identifying critical reactions. Use of MAR clearly identified the critical reactions responsible for determining the circadian cycle in the Drosophila interlocked circadian clock model. In highly robust models, while the parameter vectors are greatly varied, the critical reactions with a high sensitivity are uniquely determined. Interestingly, not only the per-tim loop but also the dclk-cyc loop strongly affect the period of PER, although the dclk-cyc loop hardly changes its amplitude and it is not potentially influential. In conclusion, MAR is a powerful method to explore wide parameter space without human-biases and to link a robust property to network architectures without knowing the exact parameter values. MAR identifies the reactions critically responsible for determining the period and amplitude in the interlocked feedback model and suggests that the circadian clock intensively evolves or designs the kinetic parameters so that it creates a highly robust cycle
    corecore