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The mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and Zika virus, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision-guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate flightless females and sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and even eliminate mosquito populations. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner.

INTRODUCTION AND OBJECTIVE:International surgical collaboration presents an opportunity to address the need for specialized urologic care and teaching in low-middle income countries (LMICs) and pro...

The mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and zika, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and eliminate mosquitoes in multigenerational population cages. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner.

Culex quinquefasciatus is a vector of a diverse range of vector-borne diseases such as avian malaria, West Nile virus (WNV), Japanese encephalitis, Eastern equine encephalitis, lymphatic filariasis, and Saint Louis encephalitis. Notably, avian malaria has played a major role in the extinction of numerous endemic island bird species, while WNV has become an important vector-borne disease in the United States. To gain further insight into C. quinquefasciatus biology and expand their genetic control toolbox, we need to develop more efficient and affordable methods for genome engineering in this species. However, some biological traits unique to Culex mosquitoes, particularly their egg rafts, have made it difficult to perform microinjection procedures required for genome engineering. To address these challenges, we have developed an optimized embryo microinjection protocol that focuses on mitigating the technical obstacles associated with the unique characteristics of Culex mosquitoes. These procedures demonstrate optimized methods for egg collection, egg raft separation and other handling procedures essential for successful microinjection in C. quinquefasciatus. When coupled with the CRISPR/Cas9 genome editing technology, these procedures allow us to achieve site-specific, efficient and heritable germline mutations, which are required to perform advanced genome engineering and develop genetic control technologies in this important, but currently understudied, disease vector.

Aedes aegypti is the principal mosquito vector for many arboviruses that increasingly infect millions of people every year. With an escalating burden of infections and the relative failure of traditional control methods, the development of innovative control measures has become of paramount importance. The use of gene drives has sparked significant enthusiasm for genetic control of mosquitoes; however, no such system has been developed in Ae. aegypti. To fill this void, here we develop several CRISPR-based split gene drives for use in this vector. With cleavage rates up to 100% and transmission rates as high as 94%, mathematical models predict that these systems could spread anti-pathogen effector genes into wild populations in a safe, confinable and reversible manner appropriate for field trials and effective for controlling disease. These findings could expedite the development of effector-linked gene drives that could safely control wild populations of Ae. aegypti to combat local pathogen transmission.

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Author(s): Becker, Brent A; Lahham, Shadi; Gonzales, Mark A; Nomura, Jason T; Bui, Michelle K; Truong, Taylor A; Stahlman, Barbara A; Fox, John C; Kehrl, Thompson | Abstract: ObjectiveThe main objective of this study was to evaluate the accuracy of emergency physician-performed point-of-care ultrasound (POCUS) for the diagnosis of small-bowel obstruction (SBO) compared to computed tomography (CT).MethodsWe performed a prospective, multicenter, observational study examining a convenience sample of adult patients with potential SBO presenting to the emergency department (ED) between July 2014 and May 2017. Each POCUS was interpreted at the bedside by the performing emergency physician and retrospectively by an expert reviewer. Test characteristics were calculated for POCUS, blinded expert interpretation, and specific POCUS parameters.ResultsA total of 217 subjects were included in the primary analysis with an overall SBO prevalence of 42.9%. For the diagnosis of SBO, POCUS demonstrated an overall sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 0.88 (95% confidence interval [CI]n= 0.80 to 0.94), 0.54 (95% CIn= 0.45 to 0.63), 1.92 (95% CIn= 1.56 to 2.35), and 0.22 (95% CIn= 0.12 to 0.39), respectively. Expert review yielded a similar sensitivity (0.89 [95% CIn= 0.81 to 0.95]) with a significantly higher specificity (0.82 [95% CIn= 0.74 to 0.88]). The more sensitive sonographic parameters for both POC sonographers and expert reviewers were small-bowel dilation ≥ 25 mm (0.87 [95% CIn= 0.79 to 0.93], 0.87 [95% CIn= 0.79 to 0.93]) and abnormal peristalsis (0.82 [95% CIn= 0.72 to 0.89], 0.85 [95% CIn= 0.76 to 0.87]). The more specific parameters for both groups were transition point (0.82 [95% CIn= 0.74 to 0.89], 0.98 [95% CIn= 0.94 to 1.00]), intraperitoneal free fluid (0.82 [95% CIn= 0.74 to 0.89], 0.93 [95% CIn= 0.87 to 0.97]), and bowel wall edema (0.76 [95% CIn= 0.67 to 0.83], 0.93 [95% CIn= 0.87 to 0.97]).ConclusionPOCUS is moderately sensitive for SBO, although less specific, when performed by a diverse group of emergency physicians across multiple EDs. Interpretation of acquired POCUS images is significantly more accurate when performed by physicians with prior emergency ultrasound fellowship training and familiarity with the sonographic appearance of SBO.

The S-phase kinase-associated protein 2 (Skp2) is overexpressed in prostate cancer and associated with tumor stage, disease recurrence, and worse patient survival. Studies also have demonstrated that Skp2 overexpression plays a critical role in development and progression of prostate cancer in several prostate cancer models, including PTEN knockout and TRAMP carcinogenesis and CWR22 xenograft models. Therefore, Skp2 is a promising target for developing new therapeutic and preventive approaches for prostate cancer. Here, we have found that gartanin, 4-prenylated xanthone from the Garcinia mangostana fruit (mangosteen), promoted Skp2 degradation in a proteasome-dependent manner in prostate cancer cells. In addition, gartanin induced the expression of FBXW2, a novel E3 ligase of SKP2 for targeted degradation, and downregulated the expression of NEDD8, leading to reduced neddylation levels of UBC12 and Cullin1. Molecular modelling analysis predicts that gartanin reasonably docks onto the regulatory subunit of NEDD8 activating enzyme E1 (NAE1) and next to the NEDD8 binding complex. More interestingly, gartanin selectively inhibits the growth of Skp2 overexpressing PC3 cells compared to parental PC cells (IC50 values for PC3/Skp2 vs. PC3 cells are approximately 4 μM vs. 14 μM). Together, our data indicate that gartanin is a novel natural agent for targeting Skp2 degradation via induction of FBXW2 expression and inhibition of neddylation. Gartanin deserves further investigation for its usefulness in prostate cancer prevention and treatment. Citation Format: Victor Pham, Michelle Bui, Raymond Rendon, Ericka Agredano, Thanh Le, Liankun Song, Xiaolin Zi. Gartanin, a 4-prenylated xanthone in the mangosteen fruit, inhibits the growth of prostate cancer cells associated with Skp2 degradation via neddylation inhibition and FBXW2 induction [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5865.