• Communications for Statistical Applications and Methods
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• v.25 no.5
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• pp.471-488
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• 2018

In this paper, we propose extending proportional hazards frailty models to allow a discrete distribution for the frailty variable. Having zero frailty can be interpreted as being immune or cured. Thus, we develop a new survival model induced by discrete frailty with zero-inflated power series distribution, which can account for overdispersion. This proposal also allows for a realistic description of non-risk individuals, since individuals cured due to intrinsic factors (immunes) are modeled by a deterministic fraction of zero-risk while those cured due to an intervention are modeled by a random fraction. We put the proposed model in a Bayesian framework and use a Markov chain Monte Carlo algorithm for the computation of posterior distribution. A simulation study is conducted to assess the proposed model and the computation algorithm. We also discuss model selection based on pseudo-Bayes factors as well as developing case influence diagnostics for the joint posterior distribution through ${\psi}-divergence$ measures. The motivating cutaneous melanoma data is analyzed for illustration purposes.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.542-549
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• 2007

During a designated period(Jan. 2003$\sim$Jun. 2006), a total of 2,051 biopsy and necropsy cases submitted to Veterinary Medical Teaching Hospital of Seoul National University and local practitioners were diagnosed as canine tumors based on microscopic evaluation in the Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University. Four hundred and twenty of 2,051 tumor specimens excluding mammary(883, 43.1%) and cutaneous(748, 36.5%) tumors were included in this retrospective study. They were composed of genital tumors(189, 45.0%) followed by alimentary(113, 26.9%), hematopoietic(52, 12.4%), urinary(20, 4.8%), bone & joint(15, 3.6%), ocular & otic(9, 2.1%), respiratory(6, 1.4%), endocrine(6, 1.4%), and miscellaneous(10, 2.4%). Particular top ten tumor most frequently diagnosed were seminoma(48, 11.4%) followed by fibrous epulis(38, 9.0%), lymphoma(38, 9.0%), leiomyoma(33, 7.9%), fibroma(26, 6.2%), ovarian cyst(19, 4.5%), melanoma(15, 3.6%), papilloma(14, 3.3%), cystic endometrial hyperplasia(13, 3.1%), granulosa cell tumor(13, 3.1%) in descending order comprising 257(61.2%). The affected age of the animals with ten frequent tumors ranged from 3 months to 17 years old with a mean of 9.2 years old(n=218). There were no significant sex prevalence except female leiomyoma. The top seven anatomical sites of tumors inclusive were gingiva(62, 14.8%), testis(61, 14.5%), ovary(48, 11.4%), vagina(40, 9.5%), uterus(36, 8.6%), lymph node(30, 7.1%), and spleen(21, 5.0%).

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6681-6684
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• 2015

Background: Metastatic cancer with invasion of skin, soft tissue and skeletal muscle is not common. Examples presenting as soft tissue masses could sometimes lead to misdiagnosis with delayed or inappropriate management. The purpose of current study was to investigate clinical characteristics in the involvement of metastatic cancer. Materials and Methods: A total of 1,097 patients complaining of skin or soft tissue masses and/or lesions were retrospectively reviewed from January 2012 to June 2013. Tumors involving skin, soft tissue and skeletal muscle of head and neck, chest wall, abdominal wall, pelvic region, back, upper and lower extremities were included in the study. Results: Fifty-seven (5.2%) patients were recognized as having malignancies on histopathological examination. The most common involvement of malignancy was basal cell carcinoma, followed by cutaneous squamous cell carcinoma, sarcoma and melanoma. The most common anatomical location in skin and soft tissue malignancies was head and neck (52.6% of the malignancies). Four (0.36%) of the malignant group were identified as metastatic cancer with the primary cancer source from lung, liver and tonsil and the most common site was upper extremities. One of them unexpectedly expired during the operation of metastatic tumor excision at the scalp. Conclusions: Discrimination between benign and malignant soft tissue tumors is crucial. Performance of imaging study could assist in the differential diagnosis and the pre-operative risk evaluation of metastatic tumors involving skin, soft tissue and skeletal muscle.

• Parasites, Hosts and Diseases
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• v.59 no.3
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• pp.189-225
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• 2021

The use of albendazole and mebendazole, i.e., benzimidazole broad-spectrum anthelmintics, in treatment of parasitic infections, as well as cancers, is briefly reviewed. These drugs are known to block the microtubule systems of parasites and mammalian cells leading to inhibition of glucose uptake and transport and finally cell death. Eventually they exhibit ovicidal, larvicidal, and vermicidal effects on parasites, and tumoricidal effects on hosts. Albendazole and mebendazole are most frequently prescribed for treatment of intestinal nematode infections (ascariasis, hookworm infections, trichuriasis, strongyloidiasis, and enterobiasis) and can also be used for intestinal tapeworm infections (taeniases and hymenolepiasis). However, these drugs also exhibit considerable therapeutic effects against tissue nematode/cestode infections (visceral, ocular, neural, and cutaneous larva migrans, anisakiasis, trichinosis, hepatic and intestinal capillariasis, angiostrongyliasis, gnathostomiasis, gongylonemiasis, thelaziasis, dracunculiasis, cerebral and subcutaneous cysticercosis, and echinococcosis). Albendazole is also used for treatment of filarial infections (lymphatic filariasis, onchocerciasis, loiasis, mansonellosis, and dirofilariasis) alone or in combination with other drugs, such as ivermectin or diethylcarbamazine. Albendazole was tried even for treatment of trematode (fascioliasis, clonorchiasis, opisthorchiasis, and intestinal fluke infections) and protozoan infections (giardiasis, vaginal trichomoniasis, cryptosporidiosis, and microsporidiosis). These drugs are generally safe with few side effects; however, when they are used for prolonged time (>14-28 days) or even only 1 time, liver toxicity and other side reactions may occur. In hookworms, Trichuris trichiura, possibly Ascaris lumbricoides, Wuchereria bancrofti, and Giardia sp., there are emerging issues of drug resistance. It is of particular note that albendazole and mebendazole have been repositioned as promising anti-cancer drugs. These drugs have been shown to be active in vitro and in vivo (animals) against liver, lung, ovary, prostate, colorectal, breast, head and neck cancers, and melanoma. Two clinical reports for albendazole and 2 case reports for mebendazole have revealed promising effects of these drugs in human patients having variable types of cancers. However, because of the toxicity of albendazole, for example, neutropenia due to myelosuppression, if high doses are used for a prolonged time, mebendazole is currently more popularly used than albendazole in anti-cancer clinical trials.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.654-660
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• 2014

Background Reactive oxygen species (ROS) damages cell molecules, and modifies cell signaling. The nuclear factor E2-related factor (Nrf2) is a critical transcription regulator, which protects cells against oxidative damage. Nrf2 expression is increased in a large number of cancers. However, little information has been reported regarding the expression of Nrf2 in skin cancers. Hence, we explored the expression of Nrf2 protein in skin cancers. Methods The Nrf2 protein expression in 24 specimens, including 6 malignant melanomas (MM), 6 squamous cell carcinomas (SCC), 6 basal cell carcinomas (BCC), and 6 normal skin tissues, was evaluated by western blotting. Immunohistochemical staining was performed. The expression of Kelch-like ECH-associated protein 1 (Keap1), the key regulator of Nrf2, was also analyzed by western blotting. Results Small interfering RNA transfection to the melanoma cell line G361 confirmed that an approximately 66 kDa band was the true Nrf2 band. The western blot revealed that the Nrf2 protein was definitely expressed in normal skin tissues, but the Nrf2 expression was decreased in MM, SCC, and BCC. Immunohistochemical examination showed that expression of Nrf2 was decreased in all skin cancer tissues compared to the normal skin tissues. Keap1 was not expressed in all malignant skin tumors and normal skin tissues by western blot. Conclusions ROS was increased in various types of cancers which proteins were highly expressed or underexpressed. This study demonstrated that the expression of Nrf2 protein was down-regulated in human malignant skin tumors. We suggest that decreased expression of Nrf2 is related to skin cancers.