Characterization of very virulent Marek's disease viruses isolated in Japan

Pathogenicity of two isolates of Marek's disease virus (MDV), MS1 and MS2, from chickens was examined in two genetically different strains of chickens, MD-susceptible P-2 chickens and less susceptible PDL-1 chickens. The isolates induced an early mortality syndrome unassociated with lymphoproliferative lesions in P-2 chickens. There were no significant differences in pathogenicity between our isolates and the Md/5 strain of very virulent MDV (vvMDV) in both P-2 and PDL-1 chickens. Protective indices of turkey herpes virus (HVT) vaccine against challenge with MS1 or MS2 in P-2 chickens were 54% and 28%, respectively, whereas HVT gave more than 80% protection in PDL-1 chickens. These results indicate that the two isolates could be classified as vvMDV. In contrast, a bivalent vaccine composed of HVT and serotype 2 MDV, and CVI988 vaccine gave good protection against challenge with the isolates in P-2 chickens; however, the best protection was given by the CBI988 vaccine. This is the first report of isolation of vvMDV in Japan.     

Myocardial cytoplasmic inclusions in chickens with haemangioma and lymphoid leukosis

Twelve of 23 adult chickens (23 to 28 weeks old) affected naturally with haemangioma and lymphoid leukosis (LL) had basophilic cytoplasmic inclusions in myocardial cells. The inclusions were oval, elongated, round or pleomorphic in shape and were rich in RNA. Electron microscopy revealed that the inclusions comprised of electron-dense small granules and doughnut-shaped particles. The significance of inclusions in LL virus infections and LL virus-induced tumours is discussed.     

Repeated piezoelectric lithotripsy for gallstones with and without ursodeoxycholic acid dissolution: A multicenter study

The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.     

Cystic cavernous hemangioma of the liver

We report an unusual case of multilocular cystic cavernous hemangioma of the liver. The patient was a 61-year-old woman without liver disfunction but who had multicystic mass lesions in the liver. Although cavernous hemangiomas are usually accurately diagnosed by the various imaging modalities, our case showed atypical features.     

Cavernous hemangioma of the rib

A 59-year-old man with an enlarged left chest wall mass that had been followed up for 3 years underwent surgical resection. The mass was pathologically diagnosed as cavernous hemangioma of the rib. This is the fourth case of this rare disease to be reported. However, it suggests that hemangioma of the rib should be considered in the differential diagnosis of rib tumors, especially in asymptomatic patients.     

Clinical study of TS-1 for inoperative and recurrent gastric cancer and evaluation of long survival cases

The clinical efficacy and safety of TS-1 therapy were studied retrospectively in patients with inoperable and recurrent gastric cancer. The subjects were 67 patients who were treated with TS-1 in our department between June 1999 and September 2004. The objective overall response rate was 41.0% (16/39; 95% confidence interval, CI, 25.3-56.7). By location, the response rate of peritoneal dissemination was high (57.1%), as were those of primary lesion (53.3%) and lymph nodes (42.9%). The prevalence of adverse reactions with a grade of 3 or 4 was 12.8%. The median survival rate (MST) was 276 days with 1-year and 2-year survival rates of 48.9% and 27.8%, respectively. This resulted in 6 long-term survival cases (over 2.5 years) after TS-1 therapy, and the longest survival time was 3y 5m after TS-1 therapy. PRs or long-term NCs after TS-1 therapy were likely to be important factors for long-term survival. In conclusion, TS-1 is safe and effective for patients with inoperable and recurrent gastric cancer, and is promising as a first-line treatment.     

Clinical evaluation of low-dose cisplatin and 5-fluorouracil as adjuvant chemoradiotherapy for advanced squamous cell carcinoma of the esophagus

The aim of this retrospective study was to evaluate the effectiveness of low-dose cisplatin and 5-fluorouracil (low-dose FP) as an adjuvant chemoradiotherapy for resected advanced squamous cell carcinoma of the esophagus. From 1994 to 1999, 57 patients who showed an invasion of the tumor over the muscularis propria (T2-T4), regional lymph node metastasis (N1), and no distant metastasis (M0) were enrolled in this analysis. Postoperative chemoradiotherapy (CRT group) was performed on 14 of the patients, and they were compared to the patients who underwent surgery alone (S group) using the matched pair algorithm. In the CRT group, chemotherapy of low-dose FP was combined with concurrent radiotherapy after the esophagectomy. A side-effect of severe dysphagia (NCI-CTC Grade 3) was observed in 4 patients (28.6%) and leukocytopenia in 1 patient (7.1%) among the CRT group. The overall survival rate of the CRT group and matched S group were 35.7% and 28.5% at 5 years, respectively, with no significant difference. In the CRT group, 7 of 14 patients (50%) had a recurrence. The recurrence rate was slightly lower than in the S group (57%), with no significant difference. This combined chemoradiotherapy using low-dose FP did not improve the prognosis of patients with resected advanced esophageal carcinoma.     

Detectability of metastatic bone tumor by Ga-67 scintigraphy

Ga-67 scintigrams in patients with malignant diseases sometimes reveal uptake of the tracer in the bone metastases. Detectability of Ga-67 scintigraphy for metastatic bone tumors and benign bone lesions was compared with that of Tc-99m bone scintigraphy. Countable bone metastases detected by bone scintigraphy were evaluated whether the lesion showed apparent, faint, or negative Ga-67 uptake. Of 47 lesions 23 (49%) showed apparent uptake and 17 (36%) showed negative uptake. On the other hand, of 71 benign bone lesions, only 7 (10%), mostly fracture/osteotomy, showed apparent uptake of the tracer. Uptake in the other benign lesions such as trauma of the ribs, spondylosis deformans, and arthrosis deformans was rather faint. In patients with multiple bone metastases, 9 patients (82%) out of 11 showed more prominent abnormal findings in Tc-99m MDP bone scintigraphy than in Ga-67 scintigraphy; that is, Ga-67 scintigraphy was not able to reveal all metastatic bone lesions. In patients with untreated or recurrent tumors, relation between Ga-67 uptake in the tumors and that in the bone metastases was evaluated. Of 7 patients with negative Ga-67 uptake in the primary tumors, 5 showed positive Ga-67 uptake in the bone metastases; that is, there seemed to be little relation between Ga-67 affinity to the primary tumors and that to the bone metastases. Mechanisms of the Ga-67 uptake in the bone metastases were discussed. Not only the tumor cells or tissues in the bone metastases but also bone mineral or osteoclasts might be the deposition sites of Ga-67.