The importance of natural enemies as the foundation of integrated pest management (IPM) is widely accepted, but few studies conduct the manipulative field experiments necessary to directly quantify their impact on p...The importance of natural enemies as the foundation of integrated pest management (IPM) is widely accepted, but few studies conduct the manipulative field experiments necessary to directly quantify their impact on pest populations in this context. This is particularly true for predators. Studying arthropod predator-prey interactions is inherently difficult: prey items are often completely consumed, individual predator-prey interactions are ephemeral (rendering their detection difficult) and the typically fluid or soft-bodied meals cannot be easily identified visually within predator guts. Serological techniques have long been used in arthropod predator gut-contents analysis, and current enzyme linked immunosorbent assays (ELISA) are highly specific and sensitive. Recently, poly- merase chain reaction (PCR) methods for gut-contents analysis have developed rapidly and they now dominate the diagnostic methods used for gut-contents analysis in field-based research. This work has identified trophic linkages within food webs, determined predator diet breadth and preference, demonstrated the importance of cannibalism and intraguild predation within and between certain taxa, and confirmed the benefits (predator persis- tence) and potential disadvantages (reduced feeding on pest species) of the availability of alternative nonpest prey. Despite considerable efforts to calibrate gut-contents assays, these methods remain qualitative. Available techniques for predator gut-contents analysis can provide rapid, accurate, cost-effective identification of predation events. As such, they perfectly compliment the ecological methods developed to directly assess predator im- pacts on prey populations but which are imperfect at identifying the key predators. These diagnostic methods for gut-contents analysis are underexploited in agricultural research and they are almost never applied in unison with the critical field experiments to measure predator impact. This paper stresses the need for a combined approach 展开更多
Malignant neoplasms of the appendix are rare and represent less than 1% of gastrointestinal cancers.Goblet cell carcinoids(GCC) tumors are a distinctive group of heterogeneous appendiceal neoplasm that exhibit unique ...Malignant neoplasms of the appendix are rare and represent less than 1% of gastrointestinal cancers.Goblet cell carcinoids(GCC) tumors are a distinctive group of heterogeneous appendiceal neoplasm that exhibit unique clinical and pathologic features.This review focuses on the current diagnostic procedures,pathogenesis,possible signaling mechanisms and treatment options for GCC.Perspectives for future research are discussed.The tumor likely arises from pluripotent intestinal epithelial crypt base stem cells.Previous findings of Notch signaling as a tumor suppressor in Neuroendocrine tumors may have a similar role in this tumor too.Loss of Notch signaling may be the driver mutation with other successive downstream mutations likely favors them into progressing and behavior similar to poorly differentiated adenocarcinoma with minimal neuroendocrine differentiation.A multidisciplinary approach is suggested for optimal outcomes.Surgery remains the main treatment modality.Simple appendectomy may be sufficient in early stages while right hemicolectomy is recommended for advanced tumors.Cytoreductive surgery with heated intraperitoneal chemotherapy may improve survival in a select few with metastatic peritoneal disease.These tumors have an unpredictable behavior even in early stages and local recurrence and delayed metastases may be seen.Lifelong surveillance is warranted.展开更多
文摘The importance of natural enemies as the foundation of integrated pest management (IPM) is widely accepted, but few studies conduct the manipulative field experiments necessary to directly quantify their impact on pest populations in this context. This is particularly true for predators. Studying arthropod predator-prey interactions is inherently difficult: prey items are often completely consumed, individual predator-prey interactions are ephemeral (rendering their detection difficult) and the typically fluid or soft-bodied meals cannot be easily identified visually within predator guts. Serological techniques have long been used in arthropod predator gut-contents analysis, and current enzyme linked immunosorbent assays (ELISA) are highly specific and sensitive. Recently, poly- merase chain reaction (PCR) methods for gut-contents analysis have developed rapidly and they now dominate the diagnostic methods used for gut-contents analysis in field-based research. This work has identified trophic linkages within food webs, determined predator diet breadth and preference, demonstrated the importance of cannibalism and intraguild predation within and between certain taxa, and confirmed the benefits (predator persis- tence) and potential disadvantages (reduced feeding on pest species) of the availability of alternative nonpest prey. Despite considerable efforts to calibrate gut-contents assays, these methods remain qualitative. Available techniques for predator gut-contents analysis can provide rapid, accurate, cost-effective identification of predation events. As such, they perfectly compliment the ecological methods developed to directly assess predator im- pacts on prey populations but which are imperfect at identifying the key predators. These diagnostic methods for gut-contents analysis are underexploited in agricultural research and they are almost never applied in unison with the critical field experiments to measure predator impact. This paper stresses the need for a combined approach
文摘Malignant neoplasms of the appendix are rare and represent less than 1% of gastrointestinal cancers.Goblet cell carcinoids(GCC) tumors are a distinctive group of heterogeneous appendiceal neoplasm that exhibit unique clinical and pathologic features.This review focuses on the current diagnostic procedures,pathogenesis,possible signaling mechanisms and treatment options for GCC.Perspectives for future research are discussed.The tumor likely arises from pluripotent intestinal epithelial crypt base stem cells.Previous findings of Notch signaling as a tumor suppressor in Neuroendocrine tumors may have a similar role in this tumor too.Loss of Notch signaling may be the driver mutation with other successive downstream mutations likely favors them into progressing and behavior similar to poorly differentiated adenocarcinoma with minimal neuroendocrine differentiation.A multidisciplinary approach is suggested for optimal outcomes.Surgery remains the main treatment modality.Simple appendectomy may be sufficient in early stages while right hemicolectomy is recommended for advanced tumors.Cytoreductive surgery with heated intraperitoneal chemotherapy may improve survival in a select few with metastatic peritoneal disease.These tumors have an unpredictable behavior even in early stages and local recurrence and delayed metastases may be seen.Lifelong surveillance is warranted.