Inositol 1,4,5-trisphosphate receptors (IP 3 Rs) play a fundamental role in generating Ca 2+ sign... more Inositol 1,4,5-trisphosphate receptors (IP 3 Rs) play a fundamental role in generating Ca 2+ signals that trigger many cellular processes in virtually all eukaryotic cells. Thus far, the three-dimensional (3D) structure of these channels has remained extremely controversial. Here, we report a subnanometer resolution electron cryomicroscopy (cryo-EM) structure of a fully functional type 1 IP 3 R from cerebellum in the closed state. The transmembrane region reveals a twisted bundle of four a helices, one from each subunit, that form a funnel shaped structure around the 4-fold symmetry axis, strikingly similar to the ion-conduction pore of K + channels. The lumenal face of IP 3 R1 has prominent densities that surround the pore entrance and similar to the highly structured turrets of Kir channels. 3D statistical analysis of the cryo-EM density map identifies high variance in the cytoplasmic region. This structural variation could be attributed to genuine structural flexibility of IP 3 R1.
Granzyme (gzm) A and gzmB have been implicated in Fas-independent nucleolytic and cytolytic proce... more Granzyme (gzm) A and gzmB have been implicated in Fas-independent nucleolytic and cytolytic processes exerted by cytotoxic T (Tc) cells, but the underlying mechanism(s) remains unclear. In this study, we compare the potential of Tc and natural killer (NK) cells of mice deficient in both gzmA and B (gzmA×B−/−) with those from single knockout mice deficient in gzmA (−/−), gzmB (−/−), or perforin (−/−) to induce nuclear damage and lysis in target cells. With the exception of perforin−/−, all in vitro– and ex vivo–derived Tc and NK cell populations from the mutant strains induced 51Cr-release in target cells at levels and with kinetics similar to those of normal mice. This contrasts with their capacity to induce apoptotic nuclear damage in target cells. In gzmA×B−/− mice, Tc/NK-mediated target cell DNA fragmentation was not observed, even after extended incubation periods (10 h), but was normal in gzmA-deficient and only impaired in gzmB-deficient mice in short-term (2–4 h), but not lon...
Chemical bonding in 2D layered materials and van der Waals solids is central to understanding and... more Chemical bonding in 2D layered materials and van der Waals solids is central to understanding and harnessing their unique electronic, magnetic, optical, thermal, and superconducting properties. Here, we report the discovery of spontaneous, bidirectional, bilayer twisting (twist angle ∼4.5°) in the metallic kagoméMgCo 6 Ge 6 at T = 100(2) K via X-ray diffraction measurements, enabled by the preparation of single crystals by the Laser Bridgman method. Despite the appearance of static twisting on cooling from T ∼300 to 100 K, no evidence for a phase transition was found in physical property measurements. Combined with the presence of an Einstein phonon mode contribution in the specific heat, this implies that the twisting exists at all temperatures but is thermally fluctuating at room temperature. Crystal Orbital Hamilton Population analysis demonstrates that the cooperative twisting between layers stabilizes the Co-kagoménetwork when coupled to strongly bonded and rigid (Ge 2) dimers that connect adjacent layers. Further modeling of the displacive disorder in the crystal structure shows the presence of a second, Mg-deficient, stacking sequence. This alternative stacking sequence also exhibits interlayer twisting, but with a different pattern, consistent with the change in electron count due to the removal of Mg. Magnetization, resistivity, and low-temperature specific heat measurements are all consistent with a Pauli paramagnetic, strongly correlated metal. Our results provide crucial insight into how chemical concepts lead to interesting electronic structures and behaviors in layered materials.
The COVID-19 pandemic has strained hospital resources and necessitated the need for predictive mo... more The COVID-19 pandemic has strained hospital resources and necessitated the need for predictive models to forecast patient care demands in order to allow for adequate staffing and resource allocation. Recently, other studies have looked at associations between Google Trends data and the number of COVID-19 cases. Expanding on this approach, we propose a vector error correction model (VECM) for the number of COVID-19 patients in a healthcare system (Census) that incorporates Google search term activity and healthcare chatbot scores. The VECM provided a good fit to Census and very good forecasting performance as assessed by hypothesis tests and mean absolute percentage prediction error. Although our study and model have limitations, we have conducted a broad and insightful search for candidate Internet variables and employed rigorous statistical methods. We have demonstrated the VECM can potentially be a valuable component to a COVID-19 surveillance program in a healthcare system.
Censoring due to a limit of detection or limit of quantification happens quite often in many medi... more Censoring due to a limit of detection or limit of quantification happens quite often in many medical studies. Conventional approaches to deal with censoring when analyzing these data include, for example, the substitution method and the complete case (CC) analysis. More recently, maximum likelihood estimation (MLE) has been increasingly used. While the CC analysis and the substitution method usually lead to biased estimates, the MLE approach appears to perform well in many situations. This article proposes an MLE approach to estimate the association between two measurements in the presence of censoring in one or both quantities. The central idea is to use a copula function to join the marginal distributions of the two measurements. In various simulation studies, we show that our approach outperforms existing conventional methods (CC and substitution analyses). In addition, rank‐based measures of global association such as Kendall's tau or Spearman's rho can be studied, hence...
In Europe only, 550 tons IONs are produced annually, which are released into the environment as a... more In Europe only, 550 tons IONs are produced annually, which are released into the environment as a consequence of both the synthesis and processing of raw materials and the use, the recycling, or the disposal of nanoparticle-containing products. The uptake of IONs might happen at different stages of the life cycle (
Monilinia fructicola and Monilinia laxa are the most destructive fungal species infecting stone f... more Monilinia fructicola and Monilinia laxa are the most destructive fungal species infecting stone fruit (Prunus species). High-throughput cDNA sequencing of M. laxa and M. fructicola isolates collected from stone fruit orchards revealed that 14% of isolates were infected with one or more of three mycoviruses: Sclerotinia sclerotiorum hypovirus 2 (SsHV2, genus Hypovirus), Fusarium poae virus 1 (FPV1, genus Betapartitivirus), and Botrytis virus F (BVF, genus Mycoflexivirus). Isolate M196 of M. fructicola was co-infected with all three viruses, and this isolate was studied further. Several methods were applied to cure M196 of one or more mycoviruses. Of these treatments, hyphal tip culture either alone or in combination with antibiotic treatment generated isogenic lines free of one or more mycoviruses. When isogenic fungal lines were cultured on nutrient agar medium in vitro, the triple mycovirus-infected parent isolate M196 grew 10% faster than any of the virus-cured isogenic lines. BVF...
Three-way helical junctions (3WJs) arise in genetic processing, and they have architectural and f... more Three-way helical junctions (3WJs) arise in genetic processing, and they have architectural and functional roles in structured nucleic acids. An internal bulge at the junction core allows the helical domains to become oriented into two possible, coaxially stacked conformers. Here, the helical stacking arrangements for a series of bulged, DNA 3WJs were examined using ensemble fluorescence resonance energy transfer (FRET) and single-molecule FRET (smFRET) approaches. The 3WJs varied according to the GC content and sequence of the junction core as well as the pyrimidine content of the internal bulge. Mg 2+ titration experiments by ensemble FRET show that both stacking conformations have similar Mg 2+ requirements for folding. Strikingly, smFRET experiments reveal that a specific junction sequence can populate both conformers and that this junction undergoes continual interconversion between the two stacked conformers. These findings will support the development of folding principles for the rational design of functional DNA nanostructures.
Here, we report the complete genome sequences of three strains isolated from alfalfa, almond drup... more Here, we report the complete genome sequences of three strains isolated from alfalfa, almond drupes, and grapes that inhibited the growth of strain 2011L-2857 We also report multiple gene clusters encoding secondary metabolites that may be responsible for the growth inhibition of .
Planarians have been long known for their regenerative ability, which hinges on pluripotency. Rec... more Planarians have been long known for their regenerative ability, which hinges on pluripotency. Recently, however, the planarian model has been successfully established for routine toxicological screens aimed to assess overproliferation, mutagenicity and tumorigenesis. In this study, we focused on planarian tumor suppressor genes (TSGs) and their role during chemically induced carcinogenic stress in Combining and proteomic screens with exposure to human carcinogen type 1A agent cadmium (Cd), we showed that many TSGs have a function in stem cells and that, in general, exposure to Cd accelerated the onset and increased the severity of the observed phenotype. This suggested that the interaction between environmental and genetic factors plays an important role in tumor development in Therefore, we further focused on the synergistic effects of Cd exposure and knockdown (KD) at the cellular and molecular levels. Cd also produced a specific proteomic landscape in homeostatic animals, with 17...
Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are an invaluable to... more Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are an invaluable tool for both basic and translational cardiovascular research. The potential that these cells hold for therapy, disease modeling and drug discovery is hampered by several bottlenecks that currently limit both the yield and the efficiency of cardiac induction. Here, we present a complete workflow for the production of ready-to-use hiPSC-CMs in a dynamic suspension bioreactor. This includes the efficient and highly reproducible differentiation of hiPSCs into cardiospheres, which display enhanced physiological maturation compared to static 3D induction in hanging drops, and a novel papain-based dissociation method that offers higher yield and viability than the broadly used dissociation reagents TrypLE and Accutase. Molecular and functional analyses of the cardiomyocytes reseeded after dissociation confirmed both the identity and the functionality of the cells, which can be used in downstream...
There are ongoing debates with respect to the prognostic roles of molecular biomarkers in sporadi... more There are ongoing debates with respect to the prognostic roles of molecular biomarkers in sporadic medullary thyroid carcinoma (MTC). In this study, we aimed at investigating the prognostic value of and mutations - the two most common mutations in sporadic MTCs. A search was conducted in four electronic databases. Relevant data were extracted and pooled into odds ratios (OR), mean differences (MD) and corresponding 95% confidence intervals (CI) using the random-effect model. We used Egger's regression test and visual of funnel plots to assess the publication bias. From 2581 studies, we included 23 studies with 964 MTCs for meta-analysis. Overall, the presence of mutation was associated with an elevated risk for lymph node metastasis (OR = 3.61; 95% CI = 2.33-5.60), distant metastasis (OR = 2.85; 95% CI = 1.64-4.94), advanced tumor stage (OR = 3.25; 95% CI = 2.02-5.25), tumor recurrence (OR = 3.01; 95% CI = 1.65-5.48) and patient mortality (OR = 2.43; 95% CI = 1.06-5.57). mutatio...
Seminars in cell & developmental biology, Jan 10, 2018
In planarians, pluripotency can be studied in vivo in the adult animal, making these animals a un... more In planarians, pluripotency can be studied in vivo in the adult animal, making these animals a unique model system where pluripotency-based regeneration (PBR)-and its therapeutic potential-can be investigated. This review focuses on recent findings to build a cloud model of fate restriction likelihood for planarian stem and progenitor cells. Recently, a computational approach based on functional and molecular profiling at the single cell level was proposed for human hematopoietic stem cells. Based on data generated both in vivo and ex vivo, we hypothesized that planarian stem cells could acquire multiple direction lineage biases, following a "badlands" landscape. Instead of a discrete tree-like hierarchy, where the potency of stem/progenitor cells reduces stepwise, we propose a Continuum of LOw-primed UnDifferentiated Planarian Stem/Progenitor Cells (CLOUD-PSPCs). Every subclass of neoblast/progenitor cells is a cloud of likelihood, as the single cell transcriptomics data ...
New isomorphs and chain-like motifs with an astounding 17 molecules in the asymmetric unit of dit... more New isomorphs and chain-like motifs with an astounding 17 molecules in the asymmetric unit of dithia-chloro-arsoles are described in addition to novel paddlewheel structures.
Stress and stressful life events have repeatedly been shown as causally related to depression. Th... more Stress and stressful life events have repeatedly been shown as causally related to depression. The Chronic Mild Stress rat model is a valid model of stress-induced depression. Like humans, rats display great heterogeneity in their response to stress and adversity. Hence some individuals are stress-sensitive and prone to develop depression-like behaviour in response to modest stressors, while others are stress-resilient and remain essentially symptom free. Compared to the large body of research, which describes stress-induced maladaptive neurobiological changes, relatively little attention has been devoted to understand resiliency to stress. The aim of the present study was to identify changes in neuronal activity, associated with stress-resilient and stress-susceptible chronic mild stress endophenotypes, by examining c-Fos expression in 13 different brain areas. Changes in c-Fos expression have been reported as associated to stressful conditions. Stress-induced modulation of neurona...
Maternal antibodies to pertussis can hamper infant immune responses to pertussis vaccines. The ef... more Maternal antibodies to pertussis can hamper infant immune responses to pertussis vaccines. The effect a maternal tetanus, diphtheria, acellular pertussis (Tdap) vaccine booster between 2 consecutive pregnancies is investigated. A prospective study was conducted in Belgium during 2008-2014 on the kinetics of maternal pertussis antibodies in unvaccinated women and their infants (group A; 86 mother-infant pairs) and in siblings born after the women received Tdap vaccine (group B; 58 mother-infant pairs). Levels of antibody to pertussis toxin, antibody to filamentous hemagglutinin, and antibody to pertactin were measured in maternal blood before and after vaccination and at both deliveries, in cord blood from both siblings, and in infants before and after they received a priming series of acellular pertussis containing vaccines. Levels of pertussis antibodies in all group B siblings at birth were significantly higher than those in their siblings at birth, even as the interval since mate...
Background Vietnam is a lower middle-income country with no national surveillance system for hosp... more Background Vietnam is a lower middle-income country with no national surveillance system for hospitalacquired infections (HAIs). We assessed the prevalence of hospital-acquired infections and antimicrobial use in adult intensive care units (ICUs) across Vietnam. Methods Monthly repeated point prevalence surveys were systematically conducted to assess HAI prevalence and antimicrobial use in 15 adult ICUs across Vietnam. Adults admitted to participating ICUs before 08:00 a.m. on the survey day were included. Results Among 3287 patients enrolled, the HAI prevalence was 29.5% (965/3266 patients, 21 missing). Pneumonia accounted for 79.4% (804/1012) of HAIs Most HAIs (84.5% [855/1012])
ICASSP '87. IEEE International Conference on Acoustics, Speech, and Signal Processing
A novel approach to image compression using vector quantization of linear (one-step) prediction e... more A novel approach to image compression using vector quantization of linear (one-step) prediction errors is presented in this paper. In order to minin,ize the image reconstruction error, we choose the optimum predictor coefficients (in a least-squares sense) that satisfy the additional constraint that the energy of the impulse response function of the inverse reconstruction filter is bounded by a small constant c. Further, the code vectors are selected such that the reconstruction error is minimized, rather than the quantization noise for the prediction error sequences. Examples demonstrating the excellent quality of the reconstructed images using our approach at bit rates below 0.65 bit/pixel are presented.
Inositol 1,4,5-trisphosphate receptors (IP 3 Rs) play a fundamental role in generating Ca 2+ sign... more Inositol 1,4,5-trisphosphate receptors (IP 3 Rs) play a fundamental role in generating Ca 2+ signals that trigger many cellular processes in virtually all eukaryotic cells. Thus far, the three-dimensional (3D) structure of these channels has remained extremely controversial. Here, we report a subnanometer resolution electron cryomicroscopy (cryo-EM) structure of a fully functional type 1 IP 3 R from cerebellum in the closed state. The transmembrane region reveals a twisted bundle of four a helices, one from each subunit, that form a funnel shaped structure around the 4-fold symmetry axis, strikingly similar to the ion-conduction pore of K + channels. The lumenal face of IP 3 R1 has prominent densities that surround the pore entrance and similar to the highly structured turrets of Kir channels. 3D statistical analysis of the cryo-EM density map identifies high variance in the cytoplasmic region. This structural variation could be attributed to genuine structural flexibility of IP 3 R1.
Granzyme (gzm) A and gzmB have been implicated in Fas-independent nucleolytic and cytolytic proce... more Granzyme (gzm) A and gzmB have been implicated in Fas-independent nucleolytic and cytolytic processes exerted by cytotoxic T (Tc) cells, but the underlying mechanism(s) remains unclear. In this study, we compare the potential of Tc and natural killer (NK) cells of mice deficient in both gzmA and B (gzmA×B−/−) with those from single knockout mice deficient in gzmA (−/−), gzmB (−/−), or perforin (−/−) to induce nuclear damage and lysis in target cells. With the exception of perforin−/−, all in vitro– and ex vivo–derived Tc and NK cell populations from the mutant strains induced 51Cr-release in target cells at levels and with kinetics similar to those of normal mice. This contrasts with their capacity to induce apoptotic nuclear damage in target cells. In gzmA×B−/− mice, Tc/NK-mediated target cell DNA fragmentation was not observed, even after extended incubation periods (10 h), but was normal in gzmA-deficient and only impaired in gzmB-deficient mice in short-term (2–4 h), but not lon...
Chemical bonding in 2D layered materials and van der Waals solids is central to understanding and... more Chemical bonding in 2D layered materials and van der Waals solids is central to understanding and harnessing their unique electronic, magnetic, optical, thermal, and superconducting properties. Here, we report the discovery of spontaneous, bidirectional, bilayer twisting (twist angle ∼4.5°) in the metallic kagoméMgCo 6 Ge 6 at T = 100(2) K via X-ray diffraction measurements, enabled by the preparation of single crystals by the Laser Bridgman method. Despite the appearance of static twisting on cooling from T ∼300 to 100 K, no evidence for a phase transition was found in physical property measurements. Combined with the presence of an Einstein phonon mode contribution in the specific heat, this implies that the twisting exists at all temperatures but is thermally fluctuating at room temperature. Crystal Orbital Hamilton Population analysis demonstrates that the cooperative twisting between layers stabilizes the Co-kagoménetwork when coupled to strongly bonded and rigid (Ge 2) dimers that connect adjacent layers. Further modeling of the displacive disorder in the crystal structure shows the presence of a second, Mg-deficient, stacking sequence. This alternative stacking sequence also exhibits interlayer twisting, but with a different pattern, consistent with the change in electron count due to the removal of Mg. Magnetization, resistivity, and low-temperature specific heat measurements are all consistent with a Pauli paramagnetic, strongly correlated metal. Our results provide crucial insight into how chemical concepts lead to interesting electronic structures and behaviors in layered materials.
The COVID-19 pandemic has strained hospital resources and necessitated the need for predictive mo... more The COVID-19 pandemic has strained hospital resources and necessitated the need for predictive models to forecast patient care demands in order to allow for adequate staffing and resource allocation. Recently, other studies have looked at associations between Google Trends data and the number of COVID-19 cases. Expanding on this approach, we propose a vector error correction model (VECM) for the number of COVID-19 patients in a healthcare system (Census) that incorporates Google search term activity and healthcare chatbot scores. The VECM provided a good fit to Census and very good forecasting performance as assessed by hypothesis tests and mean absolute percentage prediction error. Although our study and model have limitations, we have conducted a broad and insightful search for candidate Internet variables and employed rigorous statistical methods. We have demonstrated the VECM can potentially be a valuable component to a COVID-19 surveillance program in a healthcare system.
Censoring due to a limit of detection or limit of quantification happens quite often in many medi... more Censoring due to a limit of detection or limit of quantification happens quite often in many medical studies. Conventional approaches to deal with censoring when analyzing these data include, for example, the substitution method and the complete case (CC) analysis. More recently, maximum likelihood estimation (MLE) has been increasingly used. While the CC analysis and the substitution method usually lead to biased estimates, the MLE approach appears to perform well in many situations. This article proposes an MLE approach to estimate the association between two measurements in the presence of censoring in one or both quantities. The central idea is to use a copula function to join the marginal distributions of the two measurements. In various simulation studies, we show that our approach outperforms existing conventional methods (CC and substitution analyses). In addition, rank‐based measures of global association such as Kendall's tau or Spearman's rho can be studied, hence...
In Europe only, 550 tons IONs are produced annually, which are released into the environment as a... more In Europe only, 550 tons IONs are produced annually, which are released into the environment as a consequence of both the synthesis and processing of raw materials and the use, the recycling, or the disposal of nanoparticle-containing products. The uptake of IONs might happen at different stages of the life cycle (
Monilinia fructicola and Monilinia laxa are the most destructive fungal species infecting stone f... more Monilinia fructicola and Monilinia laxa are the most destructive fungal species infecting stone fruit (Prunus species). High-throughput cDNA sequencing of M. laxa and M. fructicola isolates collected from stone fruit orchards revealed that 14% of isolates were infected with one or more of three mycoviruses: Sclerotinia sclerotiorum hypovirus 2 (SsHV2, genus Hypovirus), Fusarium poae virus 1 (FPV1, genus Betapartitivirus), and Botrytis virus F (BVF, genus Mycoflexivirus). Isolate M196 of M. fructicola was co-infected with all three viruses, and this isolate was studied further. Several methods were applied to cure M196 of one or more mycoviruses. Of these treatments, hyphal tip culture either alone or in combination with antibiotic treatment generated isogenic lines free of one or more mycoviruses. When isogenic fungal lines were cultured on nutrient agar medium in vitro, the triple mycovirus-infected parent isolate M196 grew 10% faster than any of the virus-cured isogenic lines. BVF...
Three-way helical junctions (3WJs) arise in genetic processing, and they have architectural and f... more Three-way helical junctions (3WJs) arise in genetic processing, and they have architectural and functional roles in structured nucleic acids. An internal bulge at the junction core allows the helical domains to become oriented into two possible, coaxially stacked conformers. Here, the helical stacking arrangements for a series of bulged, DNA 3WJs were examined using ensemble fluorescence resonance energy transfer (FRET) and single-molecule FRET (smFRET) approaches. The 3WJs varied according to the GC content and sequence of the junction core as well as the pyrimidine content of the internal bulge. Mg 2+ titration experiments by ensemble FRET show that both stacking conformations have similar Mg 2+ requirements for folding. Strikingly, smFRET experiments reveal that a specific junction sequence can populate both conformers and that this junction undergoes continual interconversion between the two stacked conformers. These findings will support the development of folding principles for the rational design of functional DNA nanostructures.
Here, we report the complete genome sequences of three strains isolated from alfalfa, almond drup... more Here, we report the complete genome sequences of three strains isolated from alfalfa, almond drupes, and grapes that inhibited the growth of strain 2011L-2857 We also report multiple gene clusters encoding secondary metabolites that may be responsible for the growth inhibition of .
Planarians have been long known for their regenerative ability, which hinges on pluripotency. Rec... more Planarians have been long known for their regenerative ability, which hinges on pluripotency. Recently, however, the planarian model has been successfully established for routine toxicological screens aimed to assess overproliferation, mutagenicity and tumorigenesis. In this study, we focused on planarian tumor suppressor genes (TSGs) and their role during chemically induced carcinogenic stress in Combining and proteomic screens with exposure to human carcinogen type 1A agent cadmium (Cd), we showed that many TSGs have a function in stem cells and that, in general, exposure to Cd accelerated the onset and increased the severity of the observed phenotype. This suggested that the interaction between environmental and genetic factors plays an important role in tumor development in Therefore, we further focused on the synergistic effects of Cd exposure and knockdown (KD) at the cellular and molecular levels. Cd also produced a specific proteomic landscape in homeostatic animals, with 17...
Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are an invaluable to... more Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are an invaluable tool for both basic and translational cardiovascular research. The potential that these cells hold for therapy, disease modeling and drug discovery is hampered by several bottlenecks that currently limit both the yield and the efficiency of cardiac induction. Here, we present a complete workflow for the production of ready-to-use hiPSC-CMs in a dynamic suspension bioreactor. This includes the efficient and highly reproducible differentiation of hiPSCs into cardiospheres, which display enhanced physiological maturation compared to static 3D induction in hanging drops, and a novel papain-based dissociation method that offers higher yield and viability than the broadly used dissociation reagents TrypLE and Accutase. Molecular and functional analyses of the cardiomyocytes reseeded after dissociation confirmed both the identity and the functionality of the cells, which can be used in downstream...
There are ongoing debates with respect to the prognostic roles of molecular biomarkers in sporadi... more There are ongoing debates with respect to the prognostic roles of molecular biomarkers in sporadic medullary thyroid carcinoma (MTC). In this study, we aimed at investigating the prognostic value of and mutations - the two most common mutations in sporadic MTCs. A search was conducted in four electronic databases. Relevant data were extracted and pooled into odds ratios (OR), mean differences (MD) and corresponding 95% confidence intervals (CI) using the random-effect model. We used Egger's regression test and visual of funnel plots to assess the publication bias. From 2581 studies, we included 23 studies with 964 MTCs for meta-analysis. Overall, the presence of mutation was associated with an elevated risk for lymph node metastasis (OR = 3.61; 95% CI = 2.33-5.60), distant metastasis (OR = 2.85; 95% CI = 1.64-4.94), advanced tumor stage (OR = 3.25; 95% CI = 2.02-5.25), tumor recurrence (OR = 3.01; 95% CI = 1.65-5.48) and patient mortality (OR = 2.43; 95% CI = 1.06-5.57). mutatio...
Seminars in cell & developmental biology, Jan 10, 2018
In planarians, pluripotency can be studied in vivo in the adult animal, making these animals a un... more In planarians, pluripotency can be studied in vivo in the adult animal, making these animals a unique model system where pluripotency-based regeneration (PBR)-and its therapeutic potential-can be investigated. This review focuses on recent findings to build a cloud model of fate restriction likelihood for planarian stem and progenitor cells. Recently, a computational approach based on functional and molecular profiling at the single cell level was proposed for human hematopoietic stem cells. Based on data generated both in vivo and ex vivo, we hypothesized that planarian stem cells could acquire multiple direction lineage biases, following a "badlands" landscape. Instead of a discrete tree-like hierarchy, where the potency of stem/progenitor cells reduces stepwise, we propose a Continuum of LOw-primed UnDifferentiated Planarian Stem/Progenitor Cells (CLOUD-PSPCs). Every subclass of neoblast/progenitor cells is a cloud of likelihood, as the single cell transcriptomics data ...
New isomorphs and chain-like motifs with an astounding 17 molecules in the asymmetric unit of dit... more New isomorphs and chain-like motifs with an astounding 17 molecules in the asymmetric unit of dithia-chloro-arsoles are described in addition to novel paddlewheel structures.
Stress and stressful life events have repeatedly been shown as causally related to depression. Th... more Stress and stressful life events have repeatedly been shown as causally related to depression. The Chronic Mild Stress rat model is a valid model of stress-induced depression. Like humans, rats display great heterogeneity in their response to stress and adversity. Hence some individuals are stress-sensitive and prone to develop depression-like behaviour in response to modest stressors, while others are stress-resilient and remain essentially symptom free. Compared to the large body of research, which describes stress-induced maladaptive neurobiological changes, relatively little attention has been devoted to understand resiliency to stress. The aim of the present study was to identify changes in neuronal activity, associated with stress-resilient and stress-susceptible chronic mild stress endophenotypes, by examining c-Fos expression in 13 different brain areas. Changes in c-Fos expression have been reported as associated to stressful conditions. Stress-induced modulation of neurona...
Maternal antibodies to pertussis can hamper infant immune responses to pertussis vaccines. The ef... more Maternal antibodies to pertussis can hamper infant immune responses to pertussis vaccines. The effect a maternal tetanus, diphtheria, acellular pertussis (Tdap) vaccine booster between 2 consecutive pregnancies is investigated. A prospective study was conducted in Belgium during 2008-2014 on the kinetics of maternal pertussis antibodies in unvaccinated women and their infants (group A; 86 mother-infant pairs) and in siblings born after the women received Tdap vaccine (group B; 58 mother-infant pairs). Levels of antibody to pertussis toxin, antibody to filamentous hemagglutinin, and antibody to pertactin were measured in maternal blood before and after vaccination and at both deliveries, in cord blood from both siblings, and in infants before and after they received a priming series of acellular pertussis containing vaccines. Levels of pertussis antibodies in all group B siblings at birth were significantly higher than those in their siblings at birth, even as the interval since mate...
Background Vietnam is a lower middle-income country with no national surveillance system for hosp... more Background Vietnam is a lower middle-income country with no national surveillance system for hospitalacquired infections (HAIs). We assessed the prevalence of hospital-acquired infections and antimicrobial use in adult intensive care units (ICUs) across Vietnam. Methods Monthly repeated point prevalence surveys were systematically conducted to assess HAI prevalence and antimicrobial use in 15 adult ICUs across Vietnam. Adults admitted to participating ICUs before 08:00 a.m. on the survey day were included. Results Among 3287 patients enrolled, the HAI prevalence was 29.5% (965/3266 patients, 21 missing). Pneumonia accounted for 79.4% (804/1012) of HAIs Most HAIs (84.5% [855/1012])
ICASSP '87. IEEE International Conference on Acoustics, Speech, and Signal Processing
A novel approach to image compression using vector quantization of linear (one-step) prediction e... more A novel approach to image compression using vector quantization of linear (one-step) prediction errors is presented in this paper. In order to minin,ize the image reconstruction error, we choose the optimum predictor coefficients (in a least-squares sense) that satisfy the additional constraint that the energy of the impulse response function of the inverse reconstruction filter is bounded by a small constant c. Further, the code vectors are selected such that the reconstruction error is minimized, rather than the quantization noise for the prediction error sequences. Examples demonstrating the excellent quality of the reconstructed images using our approach at bit rates below 0.65 bit/pixel are presented.
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