Idiopathic Left Ventricular Tachycardia with Block Between Purkinje Potential and Ventricular Myocardium

We performed radiofrequency current catheter ablation in a patient with idiopathic LV. While mapping the inferoapical LV septum during tachycardia, spontaneous termination of tachycardia was observed with block between Purkinje (P) potential and ventricular electrogram (P-V block). The cycle length of the tachycardia was associated with prolongation of P-P interval and P-V interval. P potential recording at this site was earliest and at very low amplitude during tachycardia. The radiofrequency current at this site was successful. These findings indicated that Purkinje fiber was a critical part of the tachycardia circuit. Ablation was successful at a site where both an earliest and low amplitude P potential was recorded during tachycardia, and where P-V block that was induced by catheter manipulation was observed during tachycardia.     

Occurrence and characteristics of hypodense eosinophils in rats infected with Trichinella spiralis

Hypodense eosinophils are observed in peripheral blood and tissue from patients with eosinophilia due to helminthic infections. In this study, the variation in eosinophil density was examined in rats during Trichinella spiralis infection. Hypodense eosinophils were observed in the peripheral blood in association with Trichinella infection. In peritoneal fluid, which was representative of tissue fluid, a majority of eosinophils were hypodense regardless of the infection. During the course of tissue eosinophilia after the infection, there was a particular increase in the lowest dense cells in the population of hypodense eosinophils. Eosinophils with lower density, demonstrated larger diameters and had more potent cytotoxic activity.     

ELECTRON-MICROSCOPIC STUDY OF SCLERODERMATOUS CHRONIC GRAFT-VERSUS-HOST DISEASE

Background. Sclerodermatous chronic graft-versus-host disease (SC-GVHD) resembles systemic scleroderma (SSD) closely, both clinically and histologically. Our purpose was to try to define the morphologic differences of collagen fibers between SC-GVHD and SSD. Materials and Methods. Using electron microscopy, we compared the morphology of collagen fibers in a 15-year old girl with SC-GVHD with those of three patients with SSD. Results. In SC-GVHD, sclerosis is located in the superficial dermis and collagen fibers of irregular diameter are seen in the subepidermal area. In SSD, sclerosis is seen in the lower dermis and subcutaneous fatty tissue, and collagen fibers of irregular diameter are located in the deep dermis. Some of the collagen fibers were degenerative in the superficial dermis in SC-GVHD. We observed low-density, round structures in cross sections of collagen fibers. Conclusions. The difference in initial location and morphologic appearance of collagen fibers may indicate a different pathogenesis in SC-GVHD compared to SSD.     

Reduction of intestinal apo A-IV mRNA levels in the cirrhotic rat

In the present study, intestinal apo A-IV synthesis was investigated using a carbon tetrachloride (CCl₄)-induced cirrhosis rat model. Triglyceride (TG) content in rat cirrhotic liver was increased markedly by 170% (P< 0.001) and apo B was increased by 20% (P<0.05) compared with control levels. These results reflected the steatotic change in the liver. In contrast, TG levels in the small intestine of cirrhotic rats decreased significantly (P<0.01). In addition, intestinal apo A-IV (jejunum P< 0.001; ileum P< 0.01) and its mRNA levels (jejunum P< 0.01; ileum P< 0.05) were also reduced. The decreased apo A-IV content in the jejunum was confirmed by immunohistochemical analysis. These results indicate that intestinal apo A-IV synthesis in cirrhosis is suppressed, at least under the condition of an overnight fast. Therefore, decreased intestinal apo A-IV synthesis may relate to the decreased ability to absorb fat in cirrhosis, but a fat-loading study will be necessary to confirm this hypothesis. It is unknown from the present study why serum apo A-IV level is not significantly decreased, despite a reduction in apo A-IV synthesis. The clearance of apo A-IV by the liver may be delayed or apo A-IV synthesis may be rather markedly enhanced during fat absorption in liver cirrhosis.     

Trimethadione tolerance tests for the assessment of feasible size of hepatic resection in patients with hepatocellular carcinoma

Pre-operative evaluation of the quantity of functional remnant hepatic parenchyma after hepatectomy was carried out to predict the optimal amount of hepatic resection using the trimethadione (TMO) tolerance test. This test is an estimate based on serum diamethadione (DMO)/TMO ratio (DMO is the only metabolite of TMO) 4 h after oral administration of TMO, and computed tomography (CT) scans of the liver in patients with hepatocellular carcinoma (HCC). The percentage of remnant hepatic parenchyma was calculated pre-operatively from the remaining non-cancerous portion and the whole hepatic parenchyma, excluding the HCC portion, using the CT scans. Presumptive remnant DMO/TMO ratio was calculated by multiplying the percentage of remnant hepatic parenchyma and pre-operative serum DMO/TMO ratio in 45 patients with HCC undergoing resection. The presumptive remnant DMO/TMO ratios were 0.31 ± 0.10 (mean ±s.d.) in 42 patients who survived hepatectomy and 0.13 ± 0.02 (below 0.15) in the three patients who died from postoperative hepatic failure. Of these surviving patients, two patients who had the presumptive remnant DMO/TMO ratios under 0.15 developed postoperative severe complications. Thus, hepatectomy may not be indicated in patients where presumptive remnant DMO/TMO ratio is 0.15 and lower. These findings suggest that pre-operative measurement of presumptive remnant DMO/TMO ratio, when obtained with the CT of the liver and TMO tolerance test, is useful for prediction of the quantity of functional remnant hepatic parenchyma after hepatectomy in patients with chronic liver disease.     

Protective Effects of Local Hypothermia in Vitrectomy Under Fluctuating Intraocular Pressure

The effects of local hypothermia on the blood-aqueous barrier and retina were investigated in experimental vitrectomy under wide-ranging fluctuations of intraocular pressure.After anesthetized albino rabbits had undergone closed vitrectomy, their vitreous cavities were continuously irrigated for 60 minutes. Perfusion pressures were fluctuated alternately between 10 and 80 mmHg. The rabbits were divided into two groups in accordance with their intraocular perfusion temperatures: 8°C and 22°C. Electroretinograms were taken both before and after the irrigation. Protein and prostaglandin E₂(PGE₂) concentrations in the aqueous humor were measured on the 1st and 7th postoperative days. Histologic examination was performed on the eyes enucleated on the same days.There were no significant differences in either a- or b-wave amplitudes between the 8°C and 22°C groups. Both aqueous protein and PGE₂concentrations were significantly higher in the 22°C group than in the 8°C group on the 1st postoperative day. Histologically, the ciliary body showed remarkably more stromal edema in the 22°C group than in the 8°C group. The severity of the retinal damage did not seem to differ between the two groups.Local hypothermia during vitrectomy under fluctuating intraocular pressure inhibits the breakdown of the blood-aqueous barrier in the early postoperative stages.     

Macrocyclic peptides II. Synthesis and structure of a novel dipeptide, (2S,3′S)-2-(2′-oxo-3′-methylpiperazin-1′-yl)-propanoic acid,and its use as the unit of cyclic peptides

A new cyclic compound [(2S,3′S)-2-(2′-oxo-3′-methylpiperazin-1′-yl)-propanoic acid] obtained using (2S,7S)-2,7-dimethyl-3,6-diazaoctanedioic acid as a starting material was derived from N-t-butyloxycarbonyl-(2S,3′S)-2-(2′-oxo-3′-methylpiperazin-1′-yl)-propanoic acid in order to determine the molecular structure by X-ray crystal analysis. Two new macrocyclic peptides were prepared using the above cyclic compound and sarcosine as peptide units.     

Evaluation of renal function after laparoscopic partial nephrectomy with renal scintigraphy using 99mtechnetium-mercaptoacetyltriglycine

AIM: We evaluated the functions of an affected kidney after laparoscopic partial nephrectomy (LPN) using renal scintigraphy with (99m)technetium-mercaptoacetyltriglycine ((99m)Tc-MAG3). METHODS: Split renal function of 10 patients who underwent LPN for renal tumors was assessed using renal scintigraphy with (99m)Tc-MAG3 before surgery, and 1 week and 3 months post-surgery. RESULTS: Median operating time was 196.5 min, median tumor diameter was 2.3 cm, mean blood loss was 64 mL and mean ischemic time was 38.5 min. Median change in serum creatinine level pre- to post-surgery was 0.15 mg/dL. Median contribution of the affected kidney to total renal function (calculated using (99m)Tc-MAG3) was 50.0%, 41.7% and 36.1% before surgery, 1 week and 3 months after LPN, respectively. In one patient, the tumor was resected after cooling of the affected kidney with ice slush for 15 min, and the split renal function ratio remained as high as 50% at 3 months post-operatively despite a total ischemic time of 61 min. CONCLUSIONS: This paper evaluated renal function on the affected side before and after surgery by measuring split renal function with renal scintigraphy using (99m)Tc-MAG3. Risk factors for renal dysfunction in the affected kidney after LPN include age over 70 years with more than 30 min warm ischemic time, re-clamping of the renal artery procedure, and a warm ischemic time greater than 60 min. We believe that renal cooling with slush ice prevents renal dysfunction of the affected kidney after LPN with longer warm ischemic times. However, an easier renal cooling technique should be sought for regular use of cooling procedures in LPN.