High-Throughput Pooling and Real-Time PCR-Based Strategy for Malaria Detection

Molecular assays can provide critical information for malaria diagnosis, speciation, and drug resistance, but their cost and resource requirements limit their application to clinical malaria studies. This study describes the application of a resource-conserving testing algorithm employing sample pooling for real-time PCR assays for malaria in a cohort of 182 pregnant women in Kinshasa. A total of 1,268 peripheral blood samples were collected during the study. Using a real-time PCR assay that detects all Plasmodium species, microscopy-positive samples were amplified individually; the microscopy-negative samples were amplified after pooling the genomic DNA (gDNA) of four samples prior to testing. Of 176 microscopy-positive samples, 74 were positive by the real-time PCR assay; the 1,092 microscopy-negative samples were initially amplified in 293 pools, and subsequently, 35 samples were real-time PCR positive (3%). With the real-time PCR result as the referent standard, microscopy was 67.9% sensitive (95% confidence interval [CI], 58.3% to 76.5%) and 91.2% specific (95% CI, 89.4% to 92.8%) for malaria. In total, we detected 109 parasitemias by real-time PCR and, by pooling samples, obviated over 50% of reactions and halved the cost of testing. Our study highlights both substantial discordance between malaria diagnostics and the utility and parsimony of employing a sample pooling strategy for molecular diagnostics in clinical and epidemiologic malaria studies

Combined inhibition of tumor suppressors PTEN and PP2A drives anoikis resistance and is associated with therapy relapse in prostate cancer

Reactivation of tumor suppressor phosphatases may provide entirely novel opportunities for cancer therapy. Here, we discover clinically relevant functional co-operation between loss of activities of two human tumor suppressor phosphatases, PTEN, and PP2A. Analysis of prostate cancer tissue microarray material consisting of 358 patients treated primarily with radical prostatectomy revealed that overexpression of PP2A inhibitor protein PME-1 associates with significantly shorter time to therapy relapse in patients with PTEN-deficient PrCa. Further, PP2A inhibition by PME-1 overexpression in PTEN-deficient cell models inhibits apoptosis induction in anchorage-independent conditions (anoikis). PP2A reactivation by small molecules (SMAPs) was also found to inhibit viability of PTEN-deficient PrCa cells. Importantly, rather than regulating the well-known PP2A target pathways, PME-1 was found to physically associate with, and to regulate deformability of the nuclear lamina in PrCa cells. Mass spectrometry phosphoproteomics analysis identified several PME-1-regulated nuclear lamina constituents, and PME-1 deficient cells with compromised nuclear lamina were particularly vulnerable to apoptosis induction by mechanical stress. As a direct molecular target, Lamin A/C phosphorylation was found to be protected by PME-1-mediated PP2A inhibition under anoikis-inducing conditions. PME-1 inhibition in PrCa cells resulted in increased apoptosis in an in ovo tumor model, and PME-1-depleted cells had compromised long-term survival in zebrafish circulation. In summary we discover that PP2A reactivation by PME-1 targeting sensitizes PTEN-deficient PrCa cells to anoikis. Clinically, the results identify PME-1 as a novel candidate biomarker for increased relapse risk in PTEN-deficient PrCa, and indicate pharmacological PP2A activation as a novel potential therapeutic approach against circulating prostate cancer cells. At the general level, the results clearly emphasize the need for better understanding of phosphatases as key modulators of cancer progression. Citation Format: Christian Rupp, Aleksi Isomursu, Anna Aakula, Andrew Erickson, Song-Ping Li, Amanpreet Kaur, Pragya Shah, Yuba R. Pokharel, Lloyd Trottman, Jan Lammerding, Antti Rannikko, Pekka Taimen, Tuomas Mirtti, Ilkka Paatero, Johanna Ivaska, Jukka K. Westermarck. Combined inhibition of tumor suppressors PTEN and PP2A drives anoikis resistance and is associated with therapy relapse in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 348

Relationships, Layoffs, and Organizational Resilience: Airline Industry Responses to September 11

The terrorist attacks of September 11th, 2001 affected the U.S. airline industry more than almost any other industry. Certain of these companies emerged successful, however, and demonstrated remarkable resilience while others languished. This investigation identifies the reasons why some airline companies recovered successfully after the attacks while others struggled. Evidence is provided that layoffs after the crisis, while intended to foster recovery, instead inhibited recovery throughout the four years after the crisis. But layoffs after the crisis were strongly correlated with the lack of financial reserves and the lack of a viable business model prior to the crisis. Digging deeper, we find that having a viable business model itself depended on the extent to which positive employee relationships had been achieved and maintained over the long term. One implication of our findings is that layoffs, while reducing costs in the short term, may also undermine the positive relationships that are critical for achieving lasting recovery

Pesticide exposure and self-reported incident depression among wives in the Agricultural Health Study

BACKGROUND: Depression in women is a public health problem. Studies have reported positive associations between pesticides and depression, but few studies were prospective or presented results for women separately. OBJECTIVES: We evaluated associations between pesticide exposure and incident depression among farmers’ wives in the Agricultural Health Study, a prospective cohort study in Iowa and North Carolina. METHODS: We used data on 16,893 wives who did not report physician-diagnosed depression at enrollment (1993-1997) and who completed a follow-up telephone interview (2005-2010). Among these wives, 1,054 reported physician diagnoses of depression at follow-up. We collected information on potential confounders and on ever use of any pesticide, 11 functional and chemical classes of pesticides, and 50 specific pesticides by wives and their husbands via self-administered questionnaires at enrollment. We used inverse probability weighting to adjust for potential confounders and to account for possible selection bias induced by the death or loss of 10,639 wives during follow-up. We used log-binomial regression models to estimate risk ratios and 95% confidence intervals. RESULTS: After weighting for age at enrollment, state of residence, education level, diabetes diagnosis, and not dropping out of the cohort, wives’ incident depression was positively associated with diagnosed pesticide poisoning, but was not associated with ever using any pesticide. Use of individual pesticides or functional or chemical classes of pesticides was generally not associated with wives’ depression. Among wives who never used pesticides, husbands’ ever use of individual pesticides or functional or chemical classes of pesticides was generally not associated with wives’ incident depression. CONCLUSIONS: Our study adds further evidence that high level pesticide exposure, such as pesticide poisoning, is associated with increased risk of depression and sets a lower bound on the level of exposure related to depression, thereby providing reassurance that the moderate levels of pesticide exposure experienced by farmers’ wives likely do not increase risk