RESUMO
The spotted sea bass, Lateolabrax maculatus, is an important commercial and recreational fishery resource in Korea. Aquacultural production of this species has increased because of recent resource declines, growing consumption, and ongoing government-operated stock release programs. Therefore, the genetic characterization of hatchery populations is necessary to maintain the genetic diversity of this species and to develop more effective aquaculture practices. In this study, the genetic diversity and structure of three cultured populations in Korea were assessed using multiplex assays with 12 highly polymorphic microsatellite loci; 144 alleles were identified. The number of alleles per locus ranged from 6 to 28, with an average of 13.1. The mean observed and expected heterozygosities were 0.724 and 0.753, respectively. Low levels of inbreeding were detected according to the inbreeding coefficient (mean FIS = 0.003-0.073). All hatchery populations were significantly differentiated from each other (overall fixation index (FST) = 0.027, P < 0.01), and no population formed a separate cluster. Pairwise multilocus FST tests, estimates of genetic distance, mantel test, and principal component analyses did not show a consistent relationship between geographic and genetic distances. These results could reflect the exchange of breeds and eggs between hatcheries and/or genetic drift due to intensive breeding practices. For optimal resource management, the genetic variation of hatchery stocks should be monitored and inbreeding controlled within the spotted sea bass stocks that are being released every year. This genetic information will be useful for the management of both L. maculatus fisheries and the aquaculture industry.
Assuntos
Bass/genética , Variação Genética , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Alelos , Animais , Aquicultura , Bass/crescimento & desenvolvimento , Feminino , Pesqueiros/métodos , Frequência do Gene , Genética Populacional , Genótipo , Geografia , Endogamia , Masculino , Polimorfismo Genético , República da Coreia , Análise de Sequência de DNARESUMO
BACKGROUND AND PURPOSE: External beam radiation therapy with concurrent chemotherapy (CRT) is widely used for the treatment of unresectable pancreatic cancer. Noncoplanar (NCP) 3D conformal radiotherapy (3DCRT) and coplanar (CP) IMRT have been reported to lower the radiation dose to organs at risk (OARs). The purpose of this article is to examine the utility of noncoplanar beam angles in IMRT for the management of pancreatic cancer. MATERIALS AND METHODS: Sixteen patients who were treated with CRT for unresectable adenocarcinoma of the pancreatic head or neck were re-planned using CP and NCP beams in 3DCRT and IMRT with the Varian Eclipse treatment planning system. RESULTS: Compared to CP IMRT, NCP IMRT had similar target coverage with slightly increased maximum point dose, 5,799 versus 5,775 cGy (p = 0.008). NCP IMRT resulted in lower mean kidney dose, 787 versus 1,210 cGy (p < 0.0001) and higher mean liver dose, 1,208 versus 1,061 cGy (p < 0.0001). Also, NCP IMRT resulted in similar mean stomach dose, 1,257 versus 1,248 cGy (p = 0.86) but slightly higher mean small bowel dose, 981 versus 866 cGy (p < 0.0001). CONCLUSIONS: The NCP IMRT was able to significantly decrease bilateral kidney dose, but did not improve other dose-volume criteria. The use of NCP beam angles is preferred only in patients with risk factors for treatment-related kidney dysfunction.