RESUMEN
Currently, porcine circovirus type 2 (PCV2) is considered the major pathogen of porcine circovirus associated-diseases (PCVAD) that causes large economic losses for the swine industry in the world annually, including China. Since the first report of PCV2 in 1998, it has been drawing tremendous attention for the government, farming enterprises, farmers, and veterinary practitioners. Chinese researchers have conducted a number of molecular epidemiological work on PCV2 by molecular approaches in the past several years, which has resulted in the identification of novel PCV2 genotypes and PCV2-like agents as well as the description of new prevalence patterns. Since late 2009, commercial PCV2 vaccines, including the subunit vaccines and inactivated vaccines, have already been used in Chinese swine farms. The aim of this review is to update the insights into the prevalence and control of PCV2 in China, which would contribute to understanding the epidemiology, control measures and design of novel vaccines for PCV2.
Asunto(s)
Infecciones por Circoviridae/veterinaria , Circovirus/clasificación , Circovirus/genética , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología , Animales , China/epidemiología , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/virología , Circovirus/aislamiento & purificación , Genotipo , Epidemiología Molecular , Prevalencia , Porcinos , Vacunas Virales/administración & dosificación , Vacunas Virales/inmunologíaRESUMEN
AIM: To determine the perigastric lymph node involvement in periampullar tumors, in an attempt to optimize the surgical treatment of pylorus- preserving pancreatoduodenectomy. METHODS: We retrospectively investigated the frequence of lymph nodes involvement in perigastric regions. Distribution and number of involved lymph nodes were examined from 112 patients with carcinoma of pancreas, 59 patients with distal bile duct carcinoma, and 41 patients with carcinoma of the papilla of Vater. RESULTS: The frequency of lymphatic spread of carcinoma in pancreas; distal bile duct and papilla of Vater was 18.7%, 1.9%, 2.5% respectively. With regard to the mode of lymphatic spread in perigastric region, Infrapyloric nodes of carcinoma of the head of pancreas predominated over others,in carcinomas of the distal bile duct and the papilla of Vater, the left gastric artery, and the greater curvature lymph nodes was the only sole sites, respectively. CONCLUSION: Understanding perigastric lymphatic involvement in periampullary tumors may be helpful for choosing the appropriate surgical approaches to pancreatoduodenectomy with preservation of pylorus.