Recent Topics of Animal Health and Management

Our recent work regarding pathogenic parasites of domestic and wild animals and microbial communities in the composting processes has been summarized. Cryptosporidiosis is one of the important protozoan zoonotic diseases that causes diarrhea and occasionally death of humans, domestic animals, and wild vertebrates. We isolated a novel type of C. andersoni from cattle that grazed on the Kawatabi farm in Tohoku University, and we refer to this strain as the C. andersoni Kawatabi strain. We also isolated cryptosporidian oocysts from a dog and large Japanese field mice, Apodemus speciosus. Gene analysis suggested possibilities to be a novel type of C. canis (C. parvum dog genotype) and a new species of Cryptosporidium, respectively. A commercial microbiological additive (MA) was effective in the composting process, e.g., quicker elevation of temperature, lower emission of ammonia gas, and lower production of nitrate. Functional microbes obtained by the cultivation method with the MA did not coincide with the dominant species in the microbial community detected by DNA analyses. Various species of microbes in the MA grew at 55 and 72℃ incubation ; however, they did not coincide with the dominant species detected in chicken manure composting processes. It was clarified that the MA contained a variety of microbes, including thermophilic microbes and that these microbes did not become dominant during the composting processes. However, microbes in the MA that are smaller in number than the dominant species may act functionally in the composting process

Decontamination of mycoplasma-contaminated Orientia tsutsugamushi strains by repeating passages through cell cultures with antibiotics

Background: Mycoplasmas-contamination of Orientia tsutsugamushi, one of the obligated intracellular bacteria, is a very serious problem in in vitro studies using cell cultures because mycoplasmas have significant influence on the results of scientific studies. Only a recommended decontamination method is to passage the contaminated O. tsutsugamushi strains through mice to eliminate only mycoplasmas under influence of their immunity. However, this method sometimes does not work especially for low virulent strains of O. tsutsugamushi which are difficult to propagate in mice. In this study, we tried to eliminate mycoplasmas contaminants from both high virulent and low virulent strains of the contaminated O. tsutsugamushi by repeating passage through cell cultures with antibiotics in vitro. Results: We cultured a contaminated, high virulent strain of O. tsutsugamushi using a mouse lung fibroblasts cell line, L-929 cell in the culture medium containing lincomycin at various concentrations and repeated passages about every seven days. At the passage 5 only with 10 μg/ml of lincomycin, we did not detect mycoplasmas by two PCR based methods whereas O. tsutsugamushi continued good growth. During following four passages without lincomycin, mycoplasmas did not recover. These results suggested that mycoplasmas were completely eliminated from the high virulent strain of O. tsutsugamushi. Furthermore, by the same procedures with 10 μg/ml of lincomycin, we also eliminated mycoplasmas from a contaminated, low virulent strain of O. tsutsugamushi. Our additional assay showed that 50 μg/ml of lyncomycin did not inhibit the growth of O. tsutsugamushi, although MICs of many mycoplasmas contaminants were less than 6 μg/ml as shown previously. Conclusion: Our results showed an alternative method to eliminate mycoplasmas from the contaminated O. tsutsugamushi strains in place of in vivo passage through mice. Especially this notable method works for the decontamination not only from the high virulent strain also from the low virulent strain of O. tsutsugamushi. For further elimination, lincomycin at the limit concentration, which does not inhibit the growth of O. tsutsugamushi, can possibly eliminate most mycoplasmas from contaminated O. tsutsugamushi strains

Ovarian Sertoli-Leydig Cell Tumor with High Serum Level of alpha-Fetoprotein

A case of an ovarian Sertoli Leydig cell tumor (SLCT) associated with ele-vated serum alpha-fetoprotein (AFP) levels occurred in a 16-year-old girl. She had no signs of virilization or defeminization at the operation. In the abdominal cavity, a large and well demarcated tumor had replaced the right ovary. After the surgical removal of the tumor, the serum level of AFP decreased to within the normal limits. Microscopic examination of the tumor revealed intermediately differentiated SLCT with a retiform component. Immunohistochemical studies demonstrated the immunoreactivity of AFP in Leydig cells and Sertoli cells. The mechanisms of AFP production by SLCT were discussed here along with a review of the literature

Primary Malignant Fibrous Histiocytoma of the Pancreas : an immunohistochemical study

A case of malignant fibrous histiocytoma (MFH) which arose in the pan-creas head is presented. Only 4 cases have been documented in the world litera-ture(1-4). An 86-year-old woman who had chronic congestive heart failure showed signs of anemia and an occasional tarry stool. Computed tomography and ultrasonography indicated the existence of a tumor which was located around the pancreas and suggested invasion to the duodenum. Postmortem examinations revealed a pancreas head tumor which had a cen-tral cystic area containing a muddy-like material and blood. Invasion of the tumor to the duodenal wall was observed and the connection between the duodenal cavity and the central cystic area of the tumor was also demonstrated. The histological appearance was that of a fine fibrous tissue showing a stor-iform pattern. Immunohistochemical features also supported the histiocytic cell origin

Resection of Metachronous Lymph Node Metastases from Hepatocellular Carcinoma after Hepatectomy: Report of Four Cases

We report 4 cases of surgical resection of metachronous lymph node (LN) metastases from hepatocellular carcinoma (HCC) following hepatectomy. Clinicopathological features and results of LN dissection were investigated in the 4 patients. One patient was found to have a single metastasis in the mediastinal LNs, another had multiple metastases in the mediastinal and abdominal LNs, and the other 2 had single metastases in the abdominal LN. The locations of the abdominal LN metastases were behind the pancreas head in 2 patients and around the abdominal aorta in 1 patient. They all underwent surgical resection of metastatic LNs and had no postoperative complications. The 3 patients whose LN metastases were solitary have been alive for more than 2 years after LN resection, and one of them is free from recurrence. The patient with multiple LN metastases died 13 months after LN resection due to carcinomatosis. With the expectation of long-term survival, a single metachronous LN metastasis from HCC after hepatectomy should be resected in patients without uncontrollable intrahepatic or extrahepatic tumors

Transarterial embolization for convexity dural arteriovenous fistula

Background: Convexity dural arteriovenous fistulae (dAVF) usually reflux into cortical veins without involving the venous sinuses. Although direct drainage ligation is curative, transarterial embolization (TAE) may be an alternative treatment. Case Description: Between September 2018 and January 2021, we encountered four patients with convexity dAVFs. They were three males and one female; their age ranged from 36 to 73 years. The initial symptom was headache (n = 1) or seizure (n = 2); one patient was asymptomatic. In all patients, the feeders were external carotid arteries with drainage into the cortical veins; in two patients, there was pial arterial supply from the middle cerebral artery. All patients were successfully treated by TAE alone using either Onyx or N-butyl cyanoacrylate embolization. Two patients required two sessions. All dAVFs were completely occluded and follow-up MRI or angiograms confirmed no recurrence. Conclusion: Our small series suggests that TAE with a liquid embolic material is an appropriate first-line treatment in patients with convexity dAVFs with or without pial arterial supply

Non-radioactive Screening of p53 Mutations in Human Oral Cancers Detected by Single Strand Conformation Polymorphism Analysis : Comparison with the Protein Accumulation

p53 gene mutation and its protein accumulation are widely detected in human cancers and have prognostic significance. To examine the relationship between p53 mutation and its protein accumulation, tumor samples from 65 oral cancer patients were analyzed using both single strand conformational polymorphism (SSCP) technique to screen the presence of p53 gene mutations and immunohisto-chemistry to detect the p53 protein accumulations. Results were simultaneously associated with clinicopathological variables of the cancers and prognoses of the patients. p53 gene mutations were found in 18 cancers (7.6%), whereas aberrant accumulations of p53 protein were present in 31 cancers (47.6%). All of the oral cancers with p53 mutation showed positive immunoreactivity, but in addition, p53 protein accumulations were still found in 13 oral cancers (20%) without detect-able gene mutations. The concordance between the protein expression and the SSCP analysis was 80%. Such p53 abnormalities were significantly correlated with lymph node metastasis and clinical stage. Patients with the detectable p53 abnormalities survived for a significantly shorter period of time. p53 abnormal-ities are reliable as an indicator for evaluating malignant potential of oral can-cers

A Case of Retroperitoneal Malignant Mesenchymoma

A rare case of malignant mesenchymoma of a retroperitoneal lesion, com-posed of liposarcoma and osteosarcoma, is reported. For complete resection of the tumor, two surgical operations were performed. The first operative material showed a mass measuring 20 x 20 x 10 cm, weighing 1607g, arising from the soft tissue of the left retroperitoneum and the tumor had a smooth surface and elastic-hard consistency. The secondary operative materials exhi-bited a mass measuring 10 x 5 x 3 cm, weighing 268g. The tumor was com-posed of soft gelatinous tissues and adhered to the tail of the pancreas but was separate from the spleen. More than 3 years after the secondary operation, no recurrence has been observed. Immunohistochemical examinations showed that S-100 protein and non-specific enolase were present in the liposarcoma-tous area and that vimentin was positive in the osteosarcomatous area

Cytology of malignant endocrine tumor of the pancreas : A case report

We report here a case of malignant endocrine tumor of the pancreas with lymph node metastasis in a 67-year-old woman. The cytologic preparations ex-hibited small cells having uniform round eccentrically located nuclei and large cells showing irregular-shaped nuclei with coarse chromatin and pleomorphism. The histologic, immunohistochemical and ultrastructural findings were characte-ristic of pancreatic endocrine tumor, regardless of immunophenotypic hetero-geneity. The heterogeneity observed in cytologic specimens may be important in predicting the malignant potential of this tumor group