Pathological Aspects of Radiofrequency Catheter Ablation of the Canine Atrioventricular Node and Bundle of His

Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991.     

Chronic empyema: key-point and results of our one-step operation

A new operative method named as "Extraperiosteal air plombage" against chronic empyema were performed to 80 patients and its cure rate by the first operation was 93.8% which is a good and high rate. Know-how to perform the operation without failure is (1) to complete the excoriation of the pleural debris, (2) to seal completely the leakage such as bronchiolar fistula, (3) to perform the extraperiosteal abbration rather over much to attach the lung to the muscle layer, (4) to close the chest wall completely, and (5) to wash out thoroughly the extraperiosteal cavity with brush and enough saline solution and to use the effective antibiotica.     

Non-invasive fibrosis assessments of non-alcoholic fatty liver disease associated with low estimated glomerular filtration rate among CKD patients: the Fukuoka Kidney disease Registry Study

Clinical and Experimental Nephrology - A growing body of evidence has shown that non-alcoholic fatty liver disease (NAFLD) is associated with chronic kidney disease (CKD). Non-invasive fibrosis...     

Therapeutic effects of the combined androgen blockade therapy versus luteinizing hormone-releasing hormone analog monotherapy in patients with hormone naïve metastatic prostate cancer: a multi-institutional comparative analysis

BackgroundThe clinical benefit of the combined androgen blockade (CAB) therapy over luteinizing hormone-releasing hormone analog (LH-RHa) monotherapy for hormone naïve metastatic prostate cancer (mHNPC) is unclear. Therefore, we retrospectively compare the effectiveness of CAB with the LH-RHa monotherapy on the prognosis of Japanese patients with mHNPC.MethodsWe retrospectively evaluated the prognosis of 517 patients diagnosed with mHNPC between August 2001 and May 2017. The patients’ data were obtained from the Michinoku Urological Cancer Research Group database and Hirosaki University-related hospitals. Patients were divided into the CAB and LH-RHa monotherapy groups based on primary androgen deprivation therapy (ADT). Overall survival (OS), cancer-specific survival (CSS), and castrate-resistant prostate cancer-free survival (CRPC-FS) were compared between the two groups using the Kaplan-Meier curve analysis. Inverse probability of treatment weighting (IPTW)-adjusted Cox hazard proportional analyses was performed to investigate the effect of primary ADT on oncological outcomes.ResultsThe median age was 73 years old. The numbers of patients in the CAB and LH-RHa monotherapy groups were 447 and 70, respectively. The Kaplan-Meier curve analysis showed no significant differences in either 5-year OS (56.7% vs. 52.5%, P=0.277), CSS (61.1% vs. 56.4%, P=0.400), and CRPC-FS (33.1% vs. 31.1%, P=0.529) between the groups. IPTW-adjusted multivariate Cox hazard proportional analyses showed no significant differences in OS, CSS, and CRPC-FS between the two groups.ConclusionsNo significant differences in oncological outcomes were observed between the CAB and LH-RHa monotherapy groups in patients with mHNPC.     

Analysis of acute-phase toxicities of intensity-modulated proton therapy using a model-based approach in pharyngeal cancer patients

Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia.     

Quantitative analysis of distribution and fate of human lung cancer emboli labeled with 125I-5-iodo-2′-deoxyuridine in nude mice

The chemical and radio toxicity of ¹²⁵-5-iodo-2-deoxyuridine (¹²⁵IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of ¹²⁵IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and ¹²⁵IUDR was added to the dishes at levels ranging from 0.1 µCi/ml to 5.0 µCi/ml of media, the growth rate of the cells for 24h was similar to that of non-labeled cells. Nude mice were given intravenous injections of ¹²⁵IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis.     

Efficacy of an echo contrast agent, SH/TA-508, in color doppler sonography of mass lesions in urology

We performed a clinical phase III study with a galactosebased ecoo contrast agent, SH/TA-508, to evaluate its efficacy, safety, and usefulness for mass lesions in urology. SH/TA-508 was prepared as a suspension containing stabilized micro-air bubbles by adding water for injection just before use. SH/TA-508 was administered into the antecubital vein at an initial dose of 300 mg/ml × 5 ml followed by higher doses of 400 mg/ml × 4 ml, 300 mg/ ml × 10 ml or 400 mg/ml × 8 ml when a sufficient effect was not obtained. Efficacy was evaluated by color Doppler signal enhancement, the duration of blood flow signal enhancement, and improvement of diagnostic capacity. Fifty-nine patients with mass lesions in the kidney, prostate, testis, adrenal gland, and bladder were enrolled in the study. Up to the third dose the cumulative efficacy rates (≥2+) of color Doppler signal enhancement and duration of blood flow signal enhancement were 92% and 87%, respectively. Consequently, diagnostic capacity in 76% of the patients was remarkably improved. A light transient angialgia occurred in one patient but no other clinically significant changes were observed. It was confirmed that SH/TA-508 is a safe echo contrast agent that offers satisfactory color Doppler signal enhancement in the urologic organs mentioned above.