Background: Changes in resting membrane potential due to extracellular potassium ([K+]e) accumulation are thought to be responsible for TQ segment depression in ischemia. However, the nature of the [K+]e-TQ relationship remains to be fully elucidated. Methods: We created a carotid-coronary shunt in 21 pigs, and recorded [K+]e and TQ-segment potentials simultaneously during graded left anterior descending artery (LAD) flow reduction via 4-6 K+-sensitive electrodes placed in the LAD. Only data from K+ electrodes with calibration slopes of 55-65 mV/decade change in K+ were used. Results: While the correlation between the changes in potassium equilibrium potential (EK) and the TQ shift was linear, the regression slopes initially increased and then decreased during graded flow reduction (S = -0.338, Q = 30 mL/minute, S = -3.253, Q = 10 mL/minute, S = -0.312, Q = 0 mL/minute), i.e., TQ depression at all EK values became larger, then smaller as the flow was decreased in a stepwise manner. The inhomogeneity of changes in [K+]e and TQ potential changes and their relationship also decreased initially then increased during graded flow reduction (R = -0.237, LAD flow = 30 mL/minute; R = -0.819, LAD flow = 15 mL/minute; R = -0.115, LAD flow = 0 mL/minute). Conclusions: Although [K+]e and the TQ shift are related linearly, there is large variability in their relationship in the setting of graded coronary flow reduction. Therefore, local TQ-segment potentials cannot be used as indices of the severity of ischemic changes.
Background: Sites of high dominant frequency (DF) and complex fractionated atrial electrograms (CFAEs) are used as ablation targets to eliminate atrial fibrillation (AF). These sites are identified using spectral and time domain analyses. The frequency spectrum of the signal is determined by its cycle length as well as the morphology and amplitude of the electrogram, and these factors can affect the DF analysis. We determined the DFs, mean AF cycle lengths (fractionation intervals [FIs]), and voltages from bipolar and unipolar electrograms-and compared the values derived from the 2 types of recordings. Methods: Five patients with paroxysmal AF and 5 patients with persistent AF were included in the study. Highdensity unipolar electrograms recorded through a band-pass filter of 1-400 Hz and bipolar electrograms recorded through a band-pass filter of 30-400 Hz were obtained with the use of a 20-pole circular mapping catheter positioned in the left atrium (LA), and DF, AF cycle length, and unipolar and bipolar voltages during sinus rhythm (SR) were analyzed with the use of NavX software. Results: While the unipolar FIs were longer than the bipolar FIs, the bipolar and unipolar DFs were similar. The SR voltages of the unipolar and bipolar electrograms at CFAE sites (FIs <120 msec) were higher than those at the non-CFAE sites, but did not differ between the high DF (>8 Hz) and other DF sites. Overlap between the CFAE sites and the high DF sites identified from both bipolar and unipolar electrograms was only 7.9%. Conclusion: FIs and DFs may represent different electrophysiologic substrates.
Cerebral contusion results in a decrease of cerebral blood flow due to the formation of microthromboses, leading to secondary processes, which may represent a potential target for therapeutic intervention. Since cilostazol inhibits platelet aggregation, we would expect cilostazol to prevent microthrombosis formation following cerebral contusion. On the other hand, there is a concern that cilostazol could exacerbate the hemorrhagic lesion. The aim of our study was to examine whether cilostazol could attenuate secondary brain injury and prevent hemorrhagic progression following contusion. Specifically, we examined the effect of cilostazol on the volume of the contusion necrosis cavity and hemorrhagic progression in a cortical contusion model in the rat. Cerebral contusion was induced using a controlled cortical impact (CCI) device. Rats were randomly divided into 3 groups and orally administered cilostazol (cilostazol group), aspirin (aspirin group) or vehicle (CCI group) 1 hour after the CCI. The animals were sacrificed after 48 hours, for the evaluation of microthrombosis and extravasation of Evans blue dye (EBD), or after 14 days, for the measurement of the cavity formation after injury. Hemorrhagic progression, which is considered one of the complications of antiplatelet medications, and the EBD extravasation area at 48 hours after injury, were reduced in the cilostazol group compared with the aspirin group. Furthermore, the cavity formation was attenuated in the cilostazol group 14 days after injury compared with the controls, whereas the aspirin group exhibited marked cavity formation. These findings suggest that cilostazol exhibits neuroprotective effects without hemorrhagic complications after cerebral contusion. The mechanism of action appears to altered vascular permeability in the peripheral zone of the contusion.
Objectives: To improve the survival rate in patients with nasopharyngeal squamous cell carcinoma (NSCC). Material and Methods: A total of 56 patients with NSCC were enrolled in this study, in order to observe the long-term survival. The primary site was treated conservatively with neoadjuvant chemotherapy (NAC) and concurrent chemoradiation therapy (CCRT), using superselective intra-arterial infusion chemotherapy (SSIAC) with cisplatin, docetaxel, and 5-fluorouracil. Cervical lymph node metastasis was treated using neck dissection. Results: The 5- and 10-year overall survival rates were 67.9 and 60.5%, respectively. The 5- and 10-year survival rates improved particularly in patients with T3 cancer (96.5 and 96.5%, respectively), N1 cancer (100 and 100%, respectively), and poorly-differentiated cancer (88.2 and 79.2%, respectively). In contrast, the 5- and 10-year survival rates were worse in patients with T4 cancer (28.7 and 0%, respectively), N3 cancer (11.1 and 0%, respectively), and moderately-differentiated cancer (18.7 and 0%, respectively). There were significant differences in the overall survival rates between patients with stage III and IVA, stage III and IVB, and between IVA and IVB NSSC. Conclusion: We demonstrated that NAC and CCRT using SSIAC, with neck dissection to control cervical lymph node metastasis, were safe and effective in patients with NSCC. The introduction of maintenance therapy and intensity-modulated radiation therapy (IMRT), as well as molecular-targeted drugs and heavy-particle radiotherapy, should be considered.
Cerebral infarction in elderly patients does not always follow the same clinical course, especially compared with younger people. We believe that this is due to the existence of characteristic factors unique to elderly patients, and we surmise that brain atrophy buffers intracranial pressure in cerebral infarction. In the present study, we evaluated multiple factors, including brain atrophy, and their relationships to clinical outcomes. Between 2009 and 2011, 86 patients over 60 years of age were diagnosed by our department as having middle cerebral artery infarction. We investigated the square area of the infarction (Area method: Area) and the ASPECT score (ADS method: ADS), as well as indices of brain atrophy. The patients’ prognosis and functional outcomes were evaluated using mRS. In evaluation of the area under the curve (AUC), which was calculated from the Receiver Operating Characteristic (ROC) curve, the Area method was superior to the ADS method in predicting death two weeks after onset (Area: AUC = 0.916, ADS: AUC = 0.857). Furthermore, the AUC value was higher with the Area method after adjustment by dividing the Area by the Evans index (EI), the Area / EI, produced superior results in predicting the life outcome two weeks after the onset (AUC: Area / EI = 0.921). With respect to function prognosis, the AUC value, Area proved superior to Area / EI (p < 0.01). These results were different from the prediction of death two weeks after onset. We were able to predict the prognosis during the acute phase with higher precision using the Area method. Furthermore, we achieved greater precision using EI as an index of cerebral atrophy, and we believe that the increase in intracranial pressure was buffered by cerebral atrophy. This method will be useful for elderly people with cerebral infarction for whom it is difficult to predict the clinical course.
Thymic carcinoma is a rare disease, and the advisability of surgical resection greatly influences the prognosis. As with several protein targets in molecular medicine, efficacy has been demonstrated the thymic carcinoma, similar to other organs. However, the efficacy of Peroxisome Proliferator-Activated Receptor γ (PPARγ) for thymic carcinoma has not yet been proven. We investigated the expression of PPARγ in eight thymic carcinomas and eight thymomas (Type B3) using immunohistochemical staining with a monoclonal PPARγ antibody. We examined the incidence of the immunostaining, immunoreactive-positive rate and survival rate and considered whether PPARγ could become 1) a Diagnostic factor, 2) a Prognostic factor, and 3) Treatment preference factor for molecular targeting therapy. Results: PPARγ immunostaining and the immunoreactive-positive rate were significantly higher in the thymic carcinoma group. The survival rate was significantly better in the PPARγ-positive thymic carcinoma group. The possibility that expression of PPARγ could become a Diagnosis factor, a Prognostic factor and Treatment preference factor for molecular targeting drugs is suggested.
The patient was a man in his 60s who had undergone thoracoscopic debridement and partial pneumonectomy for pyopneumothorax. Two months after leaving the hospital, a purulent discharge was noted at the site of the surgical drain removal. Following the diagnosis of recurrent pyopneumothorax, the patient was readmitted for treatment. Initially, his condition was monitored with drainage alone. However, the patient developed antibiotic-induced renal dysfunction necessitating open-window thoracostomy. On the second postoperative day, the patient complained of difficulty breathing, and severe lung collapse was observed. As negative pressure had to be maintained within the pleural cavity, we used a vacuum-assisted closure (VAC) therapy system, which could seal an open chest wound, and placed the patient on a portable negative-pressure wound therapy system (ActiV.A.C.® Therapy Unit, manufactured by KCI; hereinafter “Acti”). By maintaining negative pressure at 25 mmHg, the collapsed lung was successfully re-expanded and the breathing improved. Although surgical closure of the open-window thoracostomy wound was initially considered as a second-stage procedure, it was not necessary as we observed narrowing of the wound opening and re-expansion of the collapsed lung. At 10 months postoperatively, complete closure and epithelization of the wound were confirmed. In addition to simplifying VAC therapy, the Acti is also portable, therefore, allowing for safe use in outpatient treatment and in the field of respiratory surgery.