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Correction: CO2 induced phase transitions in diamine-appended metal-organic frameworks.
[This corrects the article DOI: 10.1039/C5SC01828E.]
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An ANGPTL4-ceramide-protein kinase Cζ axis mediates chronic glucocorticoid exposure-induced hepatic steatosis and hypertriglyceridemia in mice.
Chronic or excess glucocorticoid exposure causes lipid disorders such as hypertriglyceridemia and hepatic steatosis. Angptl4 (angiopoietin-like 4), a primary target gene of the glucocorticoid receptor in hepatocytes and adipocytes, is required for hypertriglyceridemia and hepatic steatosis induced by the synthetic glucocorticoid dexamethasone. Angptl4 has also been shown to be required for dexamethasone-induced hepatic ceramide production. Here, we further examined the role of ceramide-mediated signaling in hepatic dyslipidemia caused by chronic glucocorticoid exposure. Using a stable isotope-labeling technique, we found that dexamethasone treatment induced the rate of hepatic de novo lipogenesis and triglyceride synthesis. These dexamethasone responses were compromised in Angptl4-null mice (Angptl4-/-). Treating mice with myriocin, an inhibitor of the rate-controlling enzyme of de novo ceramide synthesis, serine palmitoyltransferase long-chain base subunit 1 (SPTLC1)/SPTLC2, decreased dexamethasone-induced plasma and liver triglyceride levels in WT but not Angptl4-/- mice. We noted similar results in mice infected with adeno-associated virus-expressing small hairpin RNAs targeting Sptlc2. Protein phosphatase 2 phosphatase activator (PP2A) and protein kinase Cζ (PKCζ) are two known downstream effectors of ceramides. We found here that mice treated with an inhibitor of PKCζ, 2-acetyl-1,3-cyclopentanedione (ACPD), had lower levels of dexamethasone-induced triglyceride accumulation in plasma and liver. However, small hairpin RNA-mediated targeting of the catalytic PP2A subunit (Ppp2ca) had no effect on dexamethasone responses on plasma and liver triglyceride levels. Overall, our results indicate that chronic dexamethasone treatment induces an ANGPTL4-ceramide-PKCζ axis that activates hepatic de novo lipogenesis and triglyceride synthesis, resulting in lipid disorders
Correction: CO2 induced phase transitions in diamine-appended metal-organic frameworks (Chemical Science (2015) 6 (5177-5185) DOI: 10.1039/c5sc01828e)
The authors regret that there are some discrepancies reproducing the data in the original article due to the determined coordinates not being the fully optimised geometries. The authors have provided more information as follows. In the manuscript entitled \u27CO2 induced phase transitions in diamine-appended metal-organic frameworks\u27, minor errors with the attached coordinates and energies reported in the paper have recently been identified. In this communication, we correct these errors. Here, we present updated optimized geometries and binding energies. We also take this opportunity to include an extended computational details section to ensure reproducibility. In addition, we show that the overall conclusions of the paper are not affected by these changes. A detailed comparison with the results reported by Lee et al.1 revealed that the DFT optimization of the coordinates provided with the manuscript do not lead to the values reported in the manuscript, and they warrant correction. Corrected coordinates and updated tables (Tables 1-7) and figures (Fig. 1, 2, 4 and 5) are included here for calculations using the PBE functional. These structures have been repeated using a slightly tighter force threshold than in the original manuscript (details below). The M06-L calculations reported in the original manuscript are not revisited since they were performed to assess the role of dispersion. Since the publication of our work in 2015, a far more detailed study of this effect has been published by one of the authors rendering these M06-L calculations unnecessary and we refer readers interested in the role of dispersion on the carbamate formation to this more recent study by Lee et al.1 In addition to correcting our DFT calculations, we examine the effects of the revised DFT values on the lattice model in this work.We recompute the lattice model with the M06-L and PBE values fromthe original manuscript as well as the corrected PBE values reported below (Fig. 6-8 and Tables 8-10). In all three sets of isotherm plots the ordering is preserved but the inflection points are spaced differently with the new PBE numbers, leading to quantitative differences that are nonetheless qualitatively similar to previous work. Finally, we discuss different ways that CO2 can coordinate to the metal binding site, as shown in Fig. 3. We should have notedmore clearly in ourmanuscript that these were starting configurations and not necessarily the final converged structures since our goal was to try several starting geometries to determine which coordination environment around the metal site was lowest in energy. Take for example bidentate insertion. Chemical intuition suggests that this structure could rotate to one that has only one CO2 oxygen center closer to the metal than the other and we observe this in our optimized structure. The resulting geometries we obtained for the starting arrangements noted in the figure are higher in energy than the chain model as reported in our original paper.We wish to emphasize that at the time of our 2015 study, our objective was to understand whether or not CO2 was bound to the metal and if one-dimensional chain formation could lead to a step in the adsorption isotherm. It has since become clear that a far more thorough study of the arrangements of the amines is required to truly understand competing amine arrangements preset in experiment. This was outside the scope of our work. Once more, these calculations are perhaps now outdated given work in the field in recent years. We again refer interested readers to a more recent study by Lee et al.1 1. Extended computational details to ensure reproducibility In the course of rectifying the error in our calculations, we wanted to ensure that all revised calculations were converged using the exact same protocol; therefore, we repeated the PBE calculations for the pair and chain models using updated computational details given here to ensure reproducibility. The M2(dobpdc) MOF contains six unsaturated metal sites per unit cell. To calculate the binding energies of CO2 in its amine appended analogue mmen-M2(dobpdc), one mmen ligand per CO2 was added per unit cell. The smaller sized ethylenediamine (en) was used to saturate the remaining amines not involved in CO2 binding. In the case of the pair mode, two mmen-amines are included per unit cell only. All DFT calculations were performed with periodic boundary conditions carried out using the VASP 5.4.4 package (original calculations were performed with VASP 5.3.3). The PBE functional was employed to examine the energetics of CO2 adsorption.3 On-site Hubbard U corrections were employed for metal d electrons.4 The U values are determined to reproduce oxidation energies in the respective metal oxides and are given in the tables below. The electron-ion interactions in these calculations were described with the projector augmented wave (PAW) method developed by Blöchl with an energy cutoff of 550 eV.5 This combination of the PBE functional, PAW scheme, and energy cutoff was used for full geometry optimization of the various species investigated until the forces on all atoms were smaller than 0.02 eV Å-1 and the SCF convergence was set to 1 × 10-7 eV. Given the large size of the unit cell and the tests with other numbers of K-points from the original study, only results obtained from G-point calculations are reported here. Finally, heats of adsorption are now reported below along with E + ZPE values, while in the original manuscript only E + ZPE were reported. No changes were made to how the vibrational corrections were computed; however, we have included some additional details to ensure reproducibility.6 Harmonic vibrational modes (ωi) were computed for CO2 in the gas phase and its bound product state (amine-CO2-MOF complex). The framework itself was taken to be rigid and only the vibrational modes associated with the motion of the amine, the metal center, first coordination sphere (oxygen atoms bound to the metal in the MOF backbone), and (if present) the bound CO2 were computed. Since the harmonic approximation breaks down for low frequency modes, we replaced all modes less than 50 cm-1 with 50 cm-1 when computing the zero-point and thermal energies. The following standard harmonic expressions were used to compute the vibrational corrections: Zero-point vibrational energy (ZPE) is: [Equation presented here] While for the bound product, the rotational and translational degrees of freedom of CO2 have been converted to additional vibrational modes allowing one to compute the thermal correction simply as: [Equation presented here] 2. Values for the chain model The chain model used in our original study included 1 mmen- and 5 en-amines. The values from the original paper are reported in Table 1. When we repeat these calculations using the procedure described in Section 1, we obtain the values in Table 2. In addition to the chain model described above (1 mmen- and 5 en-amines per unit cell), during our original study we performed calculations with another model that was not included in the manuscript since its values yielded results further from experiment. This model includes only 1 mmen-amine per unit cell (no other amines) and was used to test the assumption that the five enamines are indeed spectators with respect to the metal dependence of the binding energy. We present the results from this model in Table 3. In the original paper we noted that the energy and bond length trends are correlated and are consistent with the Irving-Williams series. This is no longer true for all metals under investigation, with Zn being an outlier. The results for Zn can be explained by more recent work.1 3. Values for the pair model The model used to compute the pair adsorption mechanisms included 2 mmen-amines and 0 en-amines. The values in the original paper are presented in Table 5. 4. Lattice model plots The lattice models to generate adsorption isotherms for these systems were run at one temperature (∼25 °C) using four different input parameters. First the M06-L and PBE values from the original paper were used once more as it has been some time since we have run the lattice model. Then the model is repeated with the new set of values from PBE. If we compare Fig. 7 and 8, the order is preserved, but the infliction points are spaced a bit differently. This is due to the scaling factor being constant and is something we scaled for each of the different systems as well. The slope is also a bit different, but not more then we should expect for this simple lattice model. Furthermore, we only ever aimed to reproduce the step and the order of the metals. Any finer details cannot be expected to be obtained from this model. The exact values used to compute the isotherms are given in the tables below. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers
Antibiotics resistance of Vibrio spp. isolated from diseased seabass and tilapia in cage culture
Vibriosis has become one of the most important bacterial diseases in marine cultured organisms in recent years. This study was focusing on isolation and identification of Vibrio spp. isolated from diseased seabass (Lates calcarifer), tilapia (Oreochromis niloticus) and seawater from Sri Tujuh lagoon in East Coast of Malaysia; also determination of antibiotic resistance patterns among Vibrio spp. Vibrio species isolated from diseased seabass in Pantai Sri Tujuh, Tumpat, Kelantan were screened for their antibiotic sensitivity patterns by Kirby-Bauer method. A total of 47 isolates belonging to three different species were identified which are V. parahaemolyticus, V. vulnificus, and V. alginolyticus. In this study, high incidence of erythromycin, chloramphenicol and sulfamethoxazole resistance was observed among the Vibrio isolates, whereas all isolates were susceptible to oxytetracycline. Vibrio isolates were 96% resistant to one or more different classes of antibiotic, and 17 different resistance patterns were identified. The MAR index of 0.4 indicating the Vibrio spp. in these farmed fish might have been indiscriminately and continuously exposed to those antibiotics during culturing stages of the fish. This study showed that multidrug-resistant Vibrio spp. were common in diseased seabass and tilapia cultured at Sri Tujuh lagoon. These essential findings suggested involvement of seafood in transmission of these pathogen to human. In addition, oxytetracycline can be used as a treatment to combat vibriosis in diseased seabass and tilapia
Surveillance for Waterborne-Disease Outbreaks Associated with Drinking Water--United States, 2001-2002
PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and causes of waterborne-disease outbreaks (WBDOs). This surveillance system is the primary source of data concerning the scope and effects of waterborne disease outbreaks on persons in the United States.
REPORTING PERIOD COVERED: This summary includes data on WBDOs associated with drinking water that occurred during January 2001-December 2002 and on three previously unreported outbreaks that occurred during 2000.
DESCRIPTION OF SYSTEM: Public health departments in the states, territories, localities, and the Freely Associated States are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC on a standard form. The surveillance system includes data for outbreaks associated with both drinking water and recreational water; only outbreaks associated with drinking water are reported in this summary.
RESULTS: During 2001-2002, a total of 31 WBDOs associated with drinking water were reported by 19 states. These 31 outbreaks caused illness among an estimated 1,020 persons and were linked to seven deaths. The microbe or chemical that caused the outbreak was identified for 24 (77.4%) of the 31 outbreaks. Of the 24 identified outbreaks, 19 (79.2%) were associated with pathogens, and five (20.8%) were associated with acute chemical poisonings. Five outbreaks were caused by norovirus, five by parasites, and three by non-Legionella bacteria. All seven outbreaks involving acute gastrointestinal illness of unknown etiology were suspected of having an infectious cause. For the first time, this MMWR Surveillance Summary includes drinking water-associated outbreaks of Legionnaires disease (LD); six outbreaks of LD occurred during 2001-2002. Of the 25 non-Legionella associated outbreaks, 23 (92.0%) were reported in systems that used groundwater sources; nine (39.1%) of these 23 groundwater outbreaks were associated with private noncommunity wells that were not regulated by EPA.
INTERPRETATION: The number of drinking water-associated outbreaks decreased from 39 during 1999-2000 to 31 during 2001-2002. Two (8.0%) outbreaks associated with surface water occurred during 2001-2002; neither was associated with consumption of untreated water. The number of outbreaks associated with groundwater sources decreased from 28 during 1999-2000 to 23 during 2001-2002; however, the proportion of such outbreaks increased from 73.7% to 92.0%. The number of outbreaks associated with untreated groundwater decreased from 17 (44.7%) during 1999-2000 to 10 (40.0%) during 2001-2002. Outbreaks associated with private, unregulated wells remained relatively stable, although more outbreaks involving private, treated wells were reported during 2001-2002. Because the only groundwater systems that are required to disinfect their water supplies are public systems under the influence of surface water, these findings support EPA\u27s development of a groundwater rule that specifies when corrective action (including disinfection) is required.
PUBLIC HEALTH ACTION: CDC and EPA use surveillance data 1) to identify the types of water systems, their deficiencies, and the etiologic agents associated with outbreaks and 2) to evaluate the adequacy of technologies for providing safe drinking water. Surveillance data are used also to establish research priorities, which can lead to improved water-quality regulations. CDC and EPA recently completed epidemiologic studies that assess the level of waterborne illness attributable to municipal drinking water in nonoutbreak conditions. The decrease in outbreaks in surface water systems is attributable primarily to implementation of provisions of EPA rules enacted since the late 1980s. Rules under development by EPA are expected to protect the public further from microbial contaminants while addressing risk tradeoffs of disinfection byproducts in drinking water
Surveillance for Waterborne-Disease Outbreaks Associated With Recreational Water--United States, 2001-2002
PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and causes of waterborne-disease outbreaks (WBDOs) related to drinking water; tabulation of recreational water-associated outbreaks was added to the surveillance system in 1978. This surveillance system is the primary source of data concerning the scope and effects of waterborne disease outbreaks on persons in the United States.
REPORTING PERIOD COVERED: This summary includes data on WBDOs associated with recreational water that occurred during January 2001-December 2002 and on a previously unreported outbreak that occurred during 1998.
DESCRIPTION OF SYSTEM: Public health departments in the states, territories, localities, and the Freely Associated States are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC on a standard form. The surveillance system includes data for outbreaks associated with both drinking water and recreational water; only outbreaks associated with recreational water are reported in this summary.
RESULTS: During 2001-2002, a total of 65 WBDOs associated with recreational water were reported by 23 states. These 65 outbreaks caused illness among an estimated 2,536 persons; 61 persons were hospitalized, eight of whom died. This is the largest number of recreational water-associated outbreaks to occur since reporting began in 1978; the number of recreational water-associated outbreaks has increased significantly during this period (p
INTERPRETATION: The 30 outbreaks involving gastroenteritis comprised the largest proportion of recreational water-associated outbreaks during this reporting period. These outbreaks were associated most frequently with Cryptosporidium (50.0%) in treated water venues and with toxigenic Escherichia coli (25.0%) and norovirus (25.0%) in freshwater venues. The increase in the number of outbreaks since 1993 could reflect improved surveillance and reporting at the local and state level, a true increase in the number of WBDOs, or a combination of these factors.
PUBLIC HEALTH ACTION: CDC uses surveillance data to identify the etiologic agents, types of aquatics venues, water-treatment systems, and deficiencies associated with outbreaks and to evaluate the adequacy of efforts (e.g., regulations and public awareness activities) for providing safe recreational water. Surveillance data are also used to establish public health prevention priorities, which might lead to improved water-quality regulations at the local, state, and federal levels
Évaluation des risques que comporte l’exposition aux gras trans au Canada
Trans fats are undesirable because they raise LDL-cholesterol and lower HDL-cholesterol levels in the blood, which can lead to an increased risk of coronary heart disease. In the mid-1990\u27s, researchers estimated that Canadians had one of the highest average trans fat intakes in the world, estimated to be approximately 3.7% of energy. The World Health Organization recommends that average intakes of trans fats should be less than 1% of total energy. As such Canada has pursued a multi-faceted approach to decrease trans fat levels in Canadian foods. Initiatives undertaken include: mandatory nutrition labelling, the establishment of a multi-stakeholder Trans Fat Task Force to develop recommendations and strategies to eliminate trans fat in Canadian foods, and most recently the monitoring of industry\u27s efforts in reducing trans fats from their food products. Collectively, these initiatives have proven successful as average trans fat intakes have been reduced to 1.42% of overall energy. Further reductions in trans fat levels in the Canadian food supply are needed to meet the target of 1% of energy, the associated public health objectives, and the protection of vulnerable populations.Les gras trans sont indésirables, car ils augmentent la concentration sanguine en cholestérol à lipoprotéines de faible densité et abaissent celle en cholestérol à lipoprotéines de haute densité, ce qui peut mener à un risque accru de coronaropathie. Au milieu des années 1990, les chercheurs ont estimé quʹau sein de la population canadienne les apports en gras trans comptaient au nombre des plus élevés au monde en atteignant environ 3,7% de l’apport énergétique. Selon la recommandation de l’Organisation mondiale de la santé, l’apport moyen en gras trans devrait être inférieur à 1% de l’apport énergétique total. Par conséquent, le Canada a adopté une démarche à volets multiples visant à diminuer la teneur en gras trans des aliments canadiens. Les initiatives entreprises sont les suivantes: l’étiquetage nutritionnel obligatoire, l’établissement dʹun groupe de travail multilatéral, soit le Groupe d’étude surles graisses trans, dans le but d’élaborer des recommandations et des stratégies ciblant l’élimination des gras trans dans l’approvisionnement alimentaire canadien et, plus récemment, la surveillance des efforts investis par l’industrie dans la diminution des gras trans contenus dans ses produits. De concert, ces initiatives ont été couronnées de succès alors que l’apport moyen en gras trans a atteint 1,42% de l’apport énergétique total. D’autres réductions de la teneur en gras trans de l’approvisionnement alimentaire au Canada sont essentielles pour atteindre pleinement la cible de 1% de l’apport énergétique ainsi que les objectifs afférents en matière de santé publique et de protection des populations vulnérables
Recombination rate and selection strength in HIV intra-patient evolution
The evolutionary dynamics of HIV during the chronic phase of infection is
driven by the host immune response and by selective pressures exerted through
drug treatment. To understand and model the evolution of HIV quantitatively,
the parameters governing genetic diversification and the strength of selection
need to be known. While mutation rates can be measured in single replication
cycles, the relevant effective recombination rate depends on the probability of
coinfection of a cell with more than one virus and can only be inferred from
population data. However, most population genetic estimators for recombination
rates assume absence of selection and are hence of limited applicability to
HIV, since positive and purifying selection are important in HIV evolution.
Here, we estimate the rate of recombination and the distribution of selection
coefficients from time-resolved sequence data tracking the evolution of HIV
within single patients. By examining temporal changes in the genetic
composition of the population, we estimate the effective recombination to be
r=1.4e-5 recombinations per site and generation. Furthermore, we provide
evidence that selection coefficients of at least 15% of the observed
non-synonymous polymorphisms exceed 0.8% per generation. These results provide
a basis for a more detailed understanding of the evolution of HIV. A
particularly interesting case is evolution in response to drug treatment, where
recombination can facilitate the rapid acquisition of multiple resistance
mutations. With the methods developed here, more precise and more detailed
studies will be possible, as soon as data with higher time resolution and
greater sample sizes is available.Comment: to appear in PLoS Computational Biolog
Smoking patterns and chronic kidney disease in US Hispanics: Hispanic Community Health Study/Study of Latinos
Intermittent smoking is prevalent among Hispanics, but little is known about whether this smoking pattern associates with increased chronic kidney disease (CKD) risk in this population. The objective of the present study is to identify patterns of exposure associated with CKD in US Hispanics
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