Diagnosis of Hepatozoon canis in young dogs by cytology and PCR

<p>Abstract</p> <p>Background</p> <p><it>Hepatozoon canis </it>is a widespread tick-borne protozoan affecting dogs. The diagnosis of <it>H. canis </it>infection is usually performed by cytology of blood or buffy coat smears, but this method may not be sensitive. Our study aimed to evaluate the best method to achieve a parasitological diagnosis of <it>H. canis </it>infection in a population of receptive young dogs, previously negative by cytology and exposed to tick infestation for one summer season.</p> <p>Results</p> <p>A total of 73 mongrel dogs and ten beagles younger than 18 months of age, living in an animal shelter in southern Italy where dogs are highly infested by <it>Rhipicephalus sanguineus</it>, were included in this study. In March-April 2009 and in October 2009, blood and bone marrow were sampled from each dog. Blood, buffy coat and bone marrow were examined by cytology only (at the first sampling) and also by PCR for <it>H. canis </it>(second sampling). In March-April 2009, only one dog was positive for <it>H. canis </it>by cytological examination, whereas in October 2009 (after the summer season), the overall incidence of <it>H. canis </it>infection by cytological examinations was 43.9%. Molecular tests carried out on samples taken in October 2009 showed a considerably higher number of dogs positive by PCR (from 27.7% up to 51.2% on skin and buffy coat tissues, respectively), with an overall positivity of 57.8%. All animals, but one, which were positive by cytology were also PCR-positive. PCR on blood or buffy coat detected the highest number of <it>H. canis</it>-positive dogs displaying a sensitivity of 85.7% for both tissues that increased up to 98% when used in parallel. Twenty-six (74.8%) out of the 28 <it>H. canis</it>-positive dogs presented hematological abnormalities, eosinophilia being the commonest alteration observed.</p> <p>Conclusions</p> <p>The results suggest that PCR on buffy coat and blood is the best diagnostic assay for detecting <it>H. canis </it>infection in dogs, although when PCR is not available, cytology on buffy coat should be preferred to blood smear evaluation. This study has also demonstrated that <it>H. canis </it>infection can spread among young dogs infested by <it>R. sanguineus </it>and be present in the majority of the exposed population within 6 months.</p

c-Myc overexpression sensitises colon cancer cells to camptothecin-induced apoptosis

The proto-oncogene c-Myc is overexpressed in 70% of colorectal tumours and can modulate proliferation and apoptosis after cytotoxic insult. Using an isogenic cell system, we demonstrate that c-Myc overexpression in colon carcinoma LoVo cells resulted in sensitisation to camptothecin-induced apoptosis, thus identifying c-Myc as a potential marker predicting response of colorectal tumour cells to camptothecin. Both camptothecin exposure and c-Myc overexpression in LoVo cells resulted in elevation of p53 protein levels, suggesting a role of p53 in the c-Myc-imposed sensitisation to the apoptotic effects of camptothecin. This was confirmed by the ability of PFT-alpha, a specific inhibitor of p53, to attenuate camptothecin-induced apoptosis. p53 can induce the expression of p21(Waf1/Cip1), an antiproliferative protein that can facilitate DNA repair and drug resistance. Importantly, although camptothecin treatment markedly increased p21(Waf1/Cip1) levels in parental LoVo cells, this effect was abrogated in c-Myc-overexpressing derivatives. Targeted inactivation of p21(Waf1/Cip1) in HCT116 colon cancer cells resulted in significantly increased levels of apoptosis following treatment with camptothecin, demonstrating the importance of p21(Waf1/Cip1) in the response to this agent. Finally, cDNA microarray analysis was used to identify genes that are modulated in expression by c-Myc upregulation that could serve as additional markers predicting response to camptothecin. Thirty-four sequences were altered in expression over four-fold in two isogenic c-Myc-overexpressing clones compared to parental LoVo cells. Moreover, the expression of 10 of these genes was confirmed to be significantly correlated with response to camptothecin in a panel of 30 colorectal cancer cell lines

Platinum drugs in the treatment of non-small-cell lung cancer

The use of chemotherapy is considered standard therapy in patients with locally advanced non-small-cell lung cancer that cannot be treated with radiotherapy and in those with metastatic non-small-cell lung cancer and good performance status. This approach is also accepted in patients with earlier stage disease, when combined with radiotherapy in those with non-resectable locally advanced disease, or in the preoperative setting. Randomised clinical studies and meta-analyses of the literature have confirmed the beneficial survival effect of platinum-based chemotherapy. Cisplatin and carboplatin have been successfully used with other drugs in a wide variety of well-established two-drug combinations while three-drug combinations are still under investigation. Cisplatin and carboplatin use is limited by toxicity and inherent resistance. These considerations have prompted research into new platinum agents, such as the trinuclear platinum agent BBR3464, the platinum complex ZD0473 and oxaliplatin. These compounds could be developed in combination with agents such as paclitaxel, gemcitabine or vinorelbine in patients with advanced and/or refractory solid tumours

Parasites of domestic and wild canids in the region of Serra do Cipó National Park, Brazil Parasitos de canídeos domésticos e silvestres na região do Parque Nacional da Serra do Cipó - Brasil

Over recent decades, diseases have been shown to be important causes of extinctions among wild species. Greater emphasis has been given to diseases transmitted by domestic animals, which have been increasing in numbers in natural areas, along with human populations. This study had the aim of investigating the presence of intestinal helminths in wild canids (maned wolf, Chrysocyon brachyurus, and crab-eating fox, Cerdocyon thous) in the Serra do Cipó National Park (43-44º W and 19-20º S) and endo and ectoparasites of domestic dogs in the Morro da Pedreira Environmental Protection Area (an area surrounding the National Park). The Serra do Cipó is located in the state of Minas Gerais, Brazil. Among the enteroparasites found in domestic and wild canids, the following taxons were identified: Ancylostomidae, Trichuridae, Toxocara sp., Spirocerca sp., Physaloptera sp., Strongyloides sp., Cestoda, Dipylidium caninum, Diphyllobothriidae, Hymenolepidae, Anoplocephalidae, Trematoda, Acanthocephala and Isospora sp. Domestic dogs were positive for leishmaniasis and Babesia canis in serological tests. Among the ectoparasites, Rhipicephalus sanguineus, Amblyomma cajennense and Ctenocephalides felis felis were observed in domestic dogs. Variations in the chaetotaxy of the meta-episternum and posterior tibia were observed in some specimens of C. felis felis.<br>Nas últimas décadas, as doenças têm sido apontadas como importantes causas de extinção de espécies silvestres. Maior ênfase tem sido dada às doenças transmitidas por animais domésticos que crescem em número, bem como as populações humanas, em áreas naturais. O presente estudo objetivou verificar a presença de helmintos intestinais de canídeos silvestres (lobo-guará - Chrysocyon brachyurus e cachorro-do-mato - Cerdocyon thous) do Parque Nacional da Serra do Cipó (43-44º W e 19-20º S) e endo e ectoparasitos de cães domésticos da Área de Proteção Ambiental Morro da Pedreira (entorno do Parque Nacional). A Serra do Cipó está localizada no Estado de Minas Gerais, Brasil. Entre os enteroparasitos encontrados em canídeos domésticos e silvestres, os táxons seguintes, Ancylostomidae, Trichuridae, Toxocara sp., Spirocerca sp., Physaloptera sp., Strongyloides sp., Cestoda, Dipylidium caninum, Diphyllobothriidae, Hymenolepidae, Anoplocephalidae, Trematoda, Acanthocephala e Isospora sp. foram identificados. Cães domésticos foram positivos para leishmaniose e Babesia canis nos testes sorológicos. Entre os ectoparasitos, Rhipicephalus sanguineus, Amblyomma cajennense, Ctenocephalides felis felis foram observados em cães domésticos. Variações na quetotaxia do metepisterno e tíbia posterior foram observados em alguns espécimes de C. felis felis