Knockdown of COPA, Identified by Loss-of-Function Screen, Induces Apoptosis and Suppresses Tumor Growth in Mesothelioma Mouse Model

AbstractMalignant mesothelioma is a highly aggressive tumor arising from serosal surfaces of the pleura and is triggered by past exposure to asbestos. Currently, there is no widely accepted treatment for mesothelioma. Development of effective drug treatments for human cancers requires identification of therapeutic molecular targets. We therefore conducted a large-scale functional screening of mesothelioma cells using a genome-wide small interfering RNA library. We determined that knockdown of 39 genes suppressed mesothelioma cell proliferation. At least seven of the 39 genes—COPA, COPB2, EIF3D, POLR2A, PSMA6, RBM8A, and RPL18A—would be involved in anti-apoptotic function. In particular, the COPA protein was highly expressed in some mesothelioma cell lines but not in a pleural mesothelial cell line. COPA knockdown induced apoptosis and suppressed tumor growth in a mesothelioma mouse model. Therefore, COPA may have the potential of a therapeutic target and a new diagnostic marker of mesothelioma

WaSH CQI: Applying continuous quality improvement methods to water service delivery in four districts of rural northern Ghana

Continuous, safely managed water is critical to health and development, but rural service delivery faces complex challenges in low- and middle-income countries (LMICs). We report the first application of continuous quality improvement (CQI) methods to improve the microbial quality of household water for consumption (HWC) and the functionality of water sources in four rural districts of northern Ghana. We further report on the impacts of interventions developed through these methods. A local CQI team was formed and trained in CQI methods. Baseline data were collected and analyzed to identify determinants of service delivery problems and microbial safety. The CQI team randomized communities, developed an improvement package, iteratively piloted it in intervention communities, and used uptake survey data to refine the package. The final improvement package comprised safe water storage containers, refresher training for community WaSH committees and replacement of missing maintenance tools. This package significantly reduced contamination of HWC (p<0.01), and significant reduction in contamination persisted two years after implementation. Repair times in both intervention and control arms decreased relative to baseline (p<0.05), but differences between intervention and control arms were not significant at endline. Further work is needed to build on the gains in household water quality observed in this work, sustain and scale these improvements, and explore applications of CQI to other aspects of water supply and sanitation

Characteristics of aerosol and cloud particle size distributions in the tropical tropopause layer measured with optical particle counter and lidar

International audienceAn optical particle counter (OPC) is used in conjunction with lidar measurements to examine the characteristics of the particle size distribution in cirrus cloud in the tropical tropopause layer (TTL) over Thailand where the TTL is defined as the height at which temperature is lower than ?75°C in this paper. Of 11 OPC launches, cirrus cloud was detected at 10?15 km high on 7 occasions, cirrus was detected in the TTL in 6 cases, and simultaneous OPC and lidar measurements were made on two occasions. Comparison of lidar and OPC measurements reveal that the cloud heights of cirrus in the TTL varies by several hundred meters over distances of tens kilometers; hence the height is not always horizontally uniform. The mode radii of particles constituting the clouds are estimated by lidar and OPC measurements to be less than approximately 10 ?m. The regression lines of the particle size distribution with and without cirrus cloud exhibit similar features at equivalent radii of <0.8 ?m. Enhancement in the integrated number concentration at radii greater than 0.8 ?m indicates that liquid particles tend to be frozen at a radius of 0.8 ?m, with cirrus clouds above 10 km exhibiting similar features. On the other hand, enhancement in the particle size distribution at radii greater than 0.9 ?m and a peak at around 0.8 ?m in the ratio of the standard deviation of count values to that of the Poisson distribution of the averaged count values are common features of cirrus clouds in the TTL, where the ratio shows the vertical homogeneity of the particle number. These typical features suggest that the transition from liquid, sulfuric acid aerosol, to ice is more observable in the TTL and the timing of freezing may vary with height in the TTL

Characteristics of particle size distributions in the tropical tropopause based on optical particle counter and lidar measurements

International audienceAn optical particle counter (OPC) is used in conjunction with lidar measurements to examine the characteristics of the particle size distribution in cirrus cloud at the tropical tropopause (TT) over Thailand. Of 11 OPC launches, cirrus cloud was detected at 10?15 km high on 7 occasions, cirrus was detected at the TT in 6 cases, and simultaneous OPC and lidar measurements were made on two occasions. Comparison of lidar and OPC measurements reveal that the cloud height of cirrus in the TT varies by several hundred meters over distances of tens kilometers; hence the height is not horizontally uniform. The mode radii of particles constituting the clouds are estimated by lidar and OPC measurements to be less than approximately 10 ?m. The regression lines of the particle size distribution with and without cirrus cloud exhibit similar features at equivalent radii of <0.7 ?m. Enhancement in the integrated number concentration at radii greater than 0.7 ?m indicates that liquid particles tend to be frozen at a radius of 0.7 ?m, with cirrus clouds above 10 km exhibiting similar features. In addition, common features of cirrus clouds at the TT include a local maximum in the particle size distribution at 2.0 ?m and a peak between 0.5 ?m and 1.7 ?m in the ratio of the standard deviation of count values to that of the Poisson distribution of the averaged count values. Each feature implies that all ice particles in the clouds may be nucleated by the same mechanism and particles in this size range are actively frozen at the TT. These parameters are thus good indicators for checking the results of cirrus cloud models in the TT

Emergence of self-organized amoeboid movement in a multi-agent approximation of Physarum polycephalum

The giant single-celled slime mould Physarum polycephalum exhibits complex morphological adaptation and amoeboid movement as it forages for food and may be seen as a minimal example of complex robotic behaviour. Swarm computation has previously been used to explore how spatio-temporal complexity can emerge from, and be distributed within, simple component parts and their interactions. Using a particle-based swarm approach we explore the question of how to generate collective amoeboid movement from simple non-oscillatory component parts in a model of P. polycephalum. The model collective behaves as a cohesive and deformable virtual material, approximating the local coupling within the plasmodium matrix. The collective generates de-novo and complex oscillatory patterns from simple local interactions. The origin of this motor behaviour distributed within the collective rendering is morphologically adaptive, amenable to external influence and robust to simulated environmental insult. We show how to gain external influence over the collective movement by simulated chemo-attraction (pulling towards nutrient stimuli) and simulated light irradiation hazards (pushing from stimuli). The amorphous and distributed properties of the collective are demonstrated by cleaving it into two independent entities and fusing two separate entities to form a single device, thus enabling it to traverse narrow, separate or tortuous paths. We conclude by summarizing the contribution of the model to swarm-based robotics and soft-bodied modular robotics and discuss the future potential of such material approaches to the field. © 2012 IOP Publishing Ltd

Biallelic inherited SCN8A variants, a rare cause of SCN8A‐related developmental and epileptic encephalopathy

ObjectiveMonoallelic de novo gain‐of‐function variants in the voltage‐gated sodium channel SCN8A are one of the recurrent causes of severe developmental and epileptic encephalopathy (DEE). In addition, a small number of de novo or inherited monoallelic loss‐of‐function variants have been found in patients with intellectual disability, autism spectrum disorder, or movement disorders. Inherited monoallelic variants causing either gain or loss‐of‐function are also associated with less severe conditions such as benign familial infantile seizures and isolated movement disorders. In all three categories, the affected individuals are heterozygous for a SCN8A variant in combination with a wild‐type allele. In the present study, we describe two unusual families with severely affected individuals who inherited biallelic variants of SCN8A.MethodsWe identified two families with biallelic SCN8A variants by diagnostic gene panel sequencing. Functional analysis of the variants was performed using voltage clamp recordings from transfected ND7/23 cells.ResultsWe identified three probands from two unrelated families with DEE due to biallelic SCN8A variants. Each parent of an affected individual carried a single heterozygous SCN8A variant and exhibited mild cognitive impairment without seizures. In both families, functional analysis demonstrated segregation of one allele with complete loss‐of‐function, and one allele with altered biophysical properties consistent with partial loss‐of‐function.SignificanceThese studies demonstrate that SCN8A DEE may, in rare cases, result from inheritance of two variants, both of which exhibit reduced channel activity. In these families, heterozygosity for the dominant variants results in less severe disease than biallelic inheritance of two variant alleles. The clinical consequences of variants with partial and complete loss of SCN8A function are variable and likely to be influenced by genetic background.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153117/1/epi16371_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153117/2/epi16371.pd

In Vivo Simultaneous Imaging of Vascular Pool and Hypoxia with a HT-29 Tumor Model: the Application of Dual-Isotope SPECT/PET/CT

Investigation of vascularity and hypoxia in tumors is important in understanding cancer biology to developthe therapeutic strategies in cancer treatment. ------------------------------------------------------------------------ *Corresponding author . Recently, an imaging technology with the VECTor SPECT/PET/CT small-animal scanner (MILabs) has been developed to obtain simultaneous images usingtwodifferent tracers labeled with SPECT and PET nuclides, respectively. In this study, we developed amethod to simultaneously visualize vascularity and hypoxia witha human colon carcinoma HT-29tumor-bearing mouse model with 99mTc-labeled human serum albumin (99mTc-HSA) to detect blood pool, and 64Cu-diacetyl-bis (N4-methylthiosemicarbazone) (64Cu-ATSM) to detect the over-reduced conditionsunder hypoxia, by applying this SPECT/PET/CT technology.Prior to the in vivo experiments, a phantom study was conducted to confirmquantitativity of the 99mTc/64Cu dual-isotope imaging with the SPECT/PET/CT system,by comparing radioactivities detected by SPECT/PET/CT system and those of standards under the conditions of wide range of radioactivities and various content ratios, in our settings. An in vivoimaging study was conducted with HT-29 tumor-bearing mice. Both 64Cu-ATSM (37 MBq) and 99mTc-HSA (18.5 MBq) were intravenously injected into a mouse (n = 4) at 1 h and 10 min, respectively, before scanning for 20 min; the 99mTc/64Cu dual-isotope SPECT/PET/CT images were then obtained.The phantom study demonstrated that this system has high quantitativity, even when 2 isotopes co-existed and the content ratio was changed over a wide range, indicating the feasibility for in vivo experiments. In vivoSPECT/PET/CT imaging with 64Cu-ATSM and 99mTc-HSA visualized the distribution of each probe and showed that 64Cu-ATSM high-uptake regions barely overlapped with 99mTc-HSA high-uptake regions within HT-29 tumors.We developed a method to simultaneously visualize vascularity and hypoxia within HT-29tumors using in vivodual-isotope SPECT/PET/CT imaging. This methodology would be useful for studies oncancer biology with mouse tumor models anddevelopment of the treatment strategies against cancer. Examination of vascularity and hypoxia within in vivotumors is important in understanding the biology of cancer anddevelopmentof the therapeutic strategies in cancer treatment. For hypervascular tumors, antiangiogenic therapy and antivascular therapy are promising approaches. For antiangiogenic therapy, the anti-vascular endothelial growth factor antibody bevacizumab is now clinically used worldwide [1-4], and for antivascular therapy, a clinical trial withcombrestatin A4 phosphate is conducted[5]. For hypovascular tumor, which is usually associated with hypoxia, intensive treatment is necessary, since tumor hypoxia is reportedly resistant to chemotherapy and radiotherapy [6-8]. In recent years, several therapeutic methods have been proposedto damage to hypoxic regions within tumors, such as intensity modulated radiation therapy with hypoxia positron emission tomography (PET) imaging [9, 10], and carbon-ion radiotherapy, which is able to damage tumor cells even in the absence of oxygen by high linear energy transfer beam [11, 12]. However, considering the difficulty of cancer radical cure at the present moment, more effective drugs and treatment methods for antiangiogenic, antivascular, and antihypoxia therapies need to be developed. In addition, combinations of these therapies would be effective approaches, since they can attacktumor vascularity and hypoxia closely linked each other.However, it is still difficult to observe tumor vascularity and hypoxia both coincidently and concisely in in vivo tumor-bearing mouse model. Recently, a technology of single-photon emission computed tomography/positron emission tomography/computed tomography(SPECT/PET/CT) imaging with the VECTor small-animal scanner, launched from MILabs (Utrecht, Netherlands), has been reportedto obtain truly simultaneous images with twotracers labeled with SPECT and PET nuclides, respectively. Conventionally, dual-isotope imaging studies with SPECT and PET have been performed by obtaining each image independently with 2 separate systems [13, 14]. In contrast, the VECTor system is equipped with a clustered pinhole collimator, which dramatically reduces pinhole-edge penetration of high-energy annihilation ?-photons from PET nuclides and enables it to detect high-energy ?-photons derived from PET nuclides, in a manner similar to SPECT nuclides, and to obtain high-resolution images from positron emitters and single-photon emitters at the same time by separating the images based on the photon energy [15, 16]. Thus, this system has a novel concept to make images of PET nuclides, compared to the typical PET system, which measures the coincidence of annihilation ?-photons. Goorden et al. have reported that this system shows high spatial resolution, with 0.8 mm for PET nuclides and 0.5 mm for SPECT nuclides [15]. Miwa et al. also confirmed its performance in simultaneous detection of 99mTc and 18F using this system [17]. In this study, we developed a methodology to easily observe intratumoralvascularity and hypoxia in a simultaneous manner,by applyingthis SPECT/PET/CT technology. We used 99mTc-labeled human serum albumin (99mTc-HSA) labeled with a SPECT nuclide 99mTc (half-life = 6.0 h; 140 keV ?-ray: 89%) to visualize tumor vascularity by detecting blood pool [18]. The 99mTc-HSAhas been reported to detect tumor blood pool in many types of cancer, including colon cancer, renal cell carcinoma, and liver tumor in both preclinical and clinical studies [19-21]. We also used 64Cu-diacetyl-bis (N4-methylthiosemicarbazone) (64Cu-ATSM), labeled with a PET nuclide 64Cu (half-life = 12.7 h; ?+-decay: 17.4%; ??-decay: 38.5%; and electron capture: 43%) [22], to detect tumor hypoxia. The Cu-ATSM, labeled with Cu radioisotopes, such as 60Cu, 62Cu, and 64Cu, has been developed as an imaging agent targeting hypoxic regions in tumors for use with PET [23-26].Many studies have demonstrated that Cu-ATSM accumulation is associated with hypoxic conditions of tumor in vitro and in vivo[26-29]. The mechanism of radiolabeled Cu-ATSM accumulation has been studied: Cu-ATSM has small molecular sizeand high membrane permeability, and thus rapidly diffuses into cells and is reduced and trapped within cells under highly reduced intracellular conditions such as hypoxia [24, 29-31]. A clinical study with 62Cu-ATSM demonstrated that high levels of hypoxia-inducible factor-1? (HIF-1?) expression were found in Cu-ATSM uptake regions in the tumors of patients with glioma [32]. In this study, we performed simultaneous in vivo imaging using a SPECT/PET/CT with 99mTc-HSA and 64Cu-ATSM for detecting tumor vascularity and hypoxia with a HT-29 tumor-bearing mouse model