Prevalence and diversity of Hepatozoon canis in naturally infected dogs in Japanese islands and peninsulas

Canine hepatozoonosis is a worldwide protozoal disease caused by Hepatozoon canis and Hepatozoon americanum and is transmitted by ixodid ticks, Rhipicephalus and Amblyomma spp., respectively. H. canis infection is widespread in Africa, Europe, South America, and Asia, including Japan. The objective of this study was to study the distribution pattern and diversity of H. canis in naturally infected dogs in nine Japanese islands and peninsulas. Therefore, 196 hunting dogs were randomly sampled during the period from March to September 2011 and the ages and sexes were identified. Direct microscopy using Giemsa-stained blood smears revealed H. canis gametocytes in the peripheral blood of 45 (23.6 %) dogs. Polymerase chain reaction (PCR) was performed on EDTA-anticoagulated blood, initially with the common primer set (B18S-F and B18S-R) amplifying the 1,665-bp portion of the 18S rRNA gene, and then with the specific primer set (HepF and HepR) amplifying about 660 bp fragments of the same gene. Based on PCR, 84 (42.9 %) dogs were positive using the common primer and 81 (41.3 %) were positive using the specific primer. The current investigation indicated that all screened areas, except for Sado Island and Atsumi Peninsula, were infected. Yaku Island had the highest infection rate (84.6 % in males and 100.0 % in females), while Ishigaki Island showed the lowest infection rates (8.3 % in males and 17.7 % in females). Both sexes were infected with no significant difference. However, diversity of infection among the surveyed islands and peninsulas was significantly different (P?<?0.05). Although H. canis has previously been reported in dogs in Japan, the higher infection rate described in the current study and the diversity of infection in a wide range of islands strongly encourage prospective studies dealing with the prevention and treatment of the infection in dogs, as well as control of ticks.     

Histological,histochemical, and immunohistochemical studies of hippocampus in male New Zealand rabbits

The present study aims to give detailed histomorphological features of the hippocampus of adult male New Zealand rabbits. Both histological and histochemical specimens were prepared to be examined microscopically by using a light microscope. The hippocampus appeared as C-shaped hippocampal proper, dentate gyrus, and subiculum. The hippocampal proper subdivided along its length according to the density and size of its major constituent pyramidal cells into four distinct regions named Cornu Ammonis (CA1, CA2, CA3, and CA4). With the histochemical preparations, each of these regions consisted of five layers, stratum alveolus, stratum oriens, stratum pyramidale, stratum radiatum, and stratum lacunosum-moleculare. The stratum pyramidale constituted the middle dark zone and contained the principal excitatory neurons and a few interneurons. Histochemically, the pyramidal neurons along all regions of the CA reacted positively to Grimelius silver impregnation, lead hematoxylin, Gomori's aldehyde fuchsin, aldehyde thionine, Gomori's chrome alum hematoxylin, and performic acid alcian blue stains. Immunohistochemically, the pyramidal neurons reacted positively to anti-NSE antibodies. The dentate gyrus was formed of three distinct layers. The subiculum was formed of proper subiculum, presubiculum, and parasubiculum.     

Recurrence After Transanal Excision of T1 Rectal Cancer: Should We Be Concerned?

PURPOSE Transanal excision is an appealing treatment for low rectal cancers because of its low morbidity, mortality, and better functional results than transabdominal procedures. However, controversy exists about whether it compromises the potential for cure. Several, recent reports of high recurrence rates after local excision prompted us to review our results of transanal excision alone in patients with T1 rectal cancers.METHODS All patients with T1 low rectal cancer undergoing local excision alone between 1980 through 1998 were reviewed for local recurrence, distant metastasis, disease-free interval, results of salvage surgery, and overall and disease-free survival. Demographics, tumor size, distance from anal verge, and preoperative endoluminal ultrasound results also were recorded. Patients with poorly differentiated tumors, perineural or lymphovascular invasion, or with mucinous component were excluded.RESULTS Fifty-two patients underwent transanal excision during the study period. Five-year recurrence was estimated to be 29.38 percent (95 percent confidence interval, 15.39–43.48). For 52 patients, five-year, cancer-specific and overall survival rates were 89 and 75 percent respectively. Fourteen of 15 patients with recurrence underwent salvage treatment with 56.2 percent (95 percent confidence interval, 35.2–90) five-year survival rate. Gender, preoperative staging by endorectal ultrasound, distance from the anal verge, tumor size, location, and T1 status discovered after transanal excision of a villous adenoma did not influence local recurrence or tumor-specific survival.CONCLUSIONS Transanal excision for T1 rectal tumors with low-grade malignancy has a high rate of recurrence. Although overall cancer survival rates might be regarded as satisfactory, this high recurrence and low salvage rate raises the issue about the role of transanal excision alone for early rectal cancer and the possible need for adjuvant therapy or increased role of resective surgery.Presented at the meeting of The American Society of Colon and Rectal Surgeons, Chicago, Illinois, June 3 to 7, 2002.