PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (472)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
more »
1.  Remodeling Natural Products: Chemistry and Serine Hydrolase Activity of a Rocaglate-Derived β-Lactone 
Flavaglines are a class of natural products with potent insecticidal and anticancer activities. β-Lactones are a privileged structural motif found in both therapeutic agents and chemical probes. Herein, we report the synthesis, unexpected light-driven di-epimerization, and activity-based protein profiling of a novel rocaglate-derived β-lactone. In addition to in vitro inhibition of the serine hydrolases ABHD10 and ACOT1/2, the most potent β-lactone enantiomer was found to inhibit ABHD10 in PC3 cells, suggesting that derivatives of this β-lactone may serve as valuable chemical probes.
doi:10.1021/ja412431g
PMCID: PMC3978386  PMID: 24447064
2.  Treatment of Murine Cerebral Malaria by Artemisone in Combination with Conventional Antimalarial Drugs: Antiplasmodial Effects and Immune Responses 
The decreasing effectiveness of antimalarial therapy due to drug resistance necessitates constant efforts to develop new drugs. Artemisinin derivatives are the most recent drugs that have been introduced and are considered the first line of treatment, but there are already indications of Plasmodium falciparum resistance to artemisinins. Consequently, drug combinations are recommended for prevention of the induction of resistance. The research here demonstrates the effects of novel combinations of the new artemisinin derivative, artemisone, a recently described 10-alkylamino artemisinin derivative with improved antimalarial activity and reduced neurotoxicity. We here investigate its ability to kill P. falciparum in a high-throughput in vitro assay and to protect mice against lethal cerebral malaria caused by Plasmodium berghei ANKA when used alone or in combination with established antimalarial drugs. Artemisone effects against P. falciparum in vitro were synergistic with halofantrine and mefloquine, and additive with 25 other drugs, including chloroquine and doxycycline. The concentrations of artemisone combinations that were toxic against THP-1 cells in vitro were much higher than their effective antimalarial concentration. Artemisone, mefloquine, chloroquine, or piperaquine given individually mostly protected mice against cerebral malaria caused by P. berghei ANKA but did not prevent parasite recrudescence. Combinations of artemisone with any of the other three drugs did completely cure most mice of malaria. The combination of artemisone and chloroquine decreased the ratio of proinflammatory (gamma interferon, tumor necrosis factor) to anti-inflammatory (interleukin 10 [IL-10], IL-4) cytokines in the plasma of P. berghei-infected mice. Thus, artemisone in combinations with other antimalarial drugs might have a dual action, both killing parasites and limiting the potentially deleterious host inflammatory response.
doi:10.1128/AAC.01553-13
PMCID: PMC4135990  PMID: 24913162
3.  Pseudo-Outbreak of Pre-Extensively Drug-Resistant (Pre-XDR) Tuberculosis in Kinshasa: Collateral Damage Caused by False Detection of Fluoroquinolone Resistance by GenoType MTBDRsl 
Journal of Clinical Microbiology  2014;52(8):2876-2880.
Fluoroquinolones are the core drugs for the management of multidrug-resistant tuberculosis (MDR-TB). Molecular drug susceptibility testing methods provide considerable advantages for scaling up programmatic management and surveillance of drug-resistant TB. We describe here the misidentification of fluoroquinolone resistance by the GenoType MTBDRsl (MTBDRsl) (Hain Lifescience GmbH, Nehren, Germany) line probe assay (LPA) encountered during a feasibility and validation study for the introduction of this rapid drug susceptibility test in Kinshasa, Democratic Republic of Congo. The double gyrA mutation 80Ala and 90Gly represented 57% of all fluoroquinolone mutations identified from MDR-TB patient sputum samples, as confirmed by DNA sequencing. This double mutation was previously found to be associated with susceptibility to fluoroquinolones, yet it leads to absent hybridization of a wild-type band in the MTBDRsl and is thus falsely scored as resistance. Our findings suggest that MTBDRsl results must be interpreted with caution when the interpretation is based solely on the absence of a wild-type band without confirmation by visualization of a mutant band. Performance of the MTBDRsl LPA might be improved by replacing the gyrA wild-type probes by additional probes specific for well-documented gyrA mutations that confer clinically relevant resistance.
doi:10.1128/JCM.00398-14
PMCID: PMC4136193  PMID: 24871222
4.  Remodeling Natural Products: Chemistry and Serine Hydrolase Activity of a Rocaglate-Derived β-Lactone 
Flavaglines are a class of natural products with potent insecticidal and anticancer activities. β-Lactones are a privileged structural motif found in both therapeutic agents and chemical probes. Herein, we report the synthesis, unexpected light-driven di-epimerization, and activity-based protein profiling of a novel rocaglate-derived β-lactone. In addition to in vitro inhibition of the serine hydrolases ABHD10 and ACOT1/2, the most potent β-lactone enantiomer was also found to inhibit these enzymes, as well as the serine peptidases CTSA and SCPEP1, in PC3 cells.
doi:10.1021/ja412431g
PMCID: PMC3978386  PMID: 24447064
5.  Preliminary results for salt aerosol production intended for marine cloud brightening, using effervescent spray atomization 
The large-scale production of vast numbers of suitable salt nuclei and their upward launch is one of the main technological barriers to the experimental testing of marine cloud brightening (MCB). Very promising, though not definitive, results have been obtained using an adapted version of effervescent spray atomization. The process is simple, robust and inexpensive. This form of effervescent spraying uses only pressurized water and air sprayed from small nozzles to obtain very fine distributions. While it is far from optimized, and may not be the best method if full deployment is ever desired, we believe that even in its present form the process would lend itself well to preliminary field test investigations of MCB. Measurements obtained using standard aerosol instrumentation show approximately lognormal distributions of salt nuclei with median diameters of approximately 65 nm and geometric standard deviations slightly less than 2. However, these measurements are not in agreement with those based on scanning electron microscopy imaging of collected particles, an observation that has not yet been explained. Assuming the above distribution, 1015 particles per second could be made with 21 kW of spray power, using approximately 200 nozzles. It is envisioned that existing snow making equipment can be adapted to launch the nuclei 60–100 m into the air, requiring approximately 20 kW of additional power.
doi:10.1098/rsta.2014.0055
PMCID: PMC4240953  PMID: 25404673
salt aerosol production; marine cloud brightening; effervescent spray atomization
6.  Atomic electric fields revealed by a quantum mechanical approach to electron picodiffraction 
Nature Communications  2014;5:5653.
By focusing electrons on probes with a diameter of 50 pm, aberration-corrected scanning transmission electron microscopy (STEM) is currently crossing the border to probing subatomic details. A major challenge is the measurement of atomic electric fields using differential phase contrast (DPC) microscopy, traditionally exploiting the concept of a field-induced shift of diffraction patterns. Here we present a simplified quantum theoretical interpretation of DPC. This enables us to calculate the momentum transferred to the STEM probe from diffracted intensities recorded on a pixel array instead of conventional segmented bright-field detectors. The methodical development yielding atomic electric field, charge and electron density is performed using simulations for binary GaN as an ideal model system. We then present a detailed experimental study of SrTiO3 yielding atomic electric fields, validated by comprehensive simulations. With this interpretation and upgraded instrumentation, STEM is capable of quantifying atomic electric fields and high-contrast imaging of light atoms.
Advances in electron microscopy are enabling ever smaller features to be probed, with the measurement of atomic electric fields standing as a major challenge. Towards that aim, Müller et al. present a simplified theoretical approach for enhancing the resolution in differential phase contrast microscopy.
doi:10.1038/ncomms6653
PMCID: PMC4275586  PMID: 25501385
8.  Development of trigger-based semi-automated surveillance of ventilator-associated pneumonia and central line-associated bloodstream infections in a Dutch intensive care 
Annals of Intensive Care  2014;4(1):40.
Background
Availability of a patient data management system (PDMS) has created the opportunity to develop trigger-based electronic surveillance systems (ESSs). The aim was to evaluate a semi-automated trigger-based ESS for the detection of ventilator-associated pneumonia (VAP) and central line-associated blood stream infections (CLABSIs) in the intensive care.
Methods
Prospective comparison of surveillance was based on a semi-automated ESS with and without trigger. Components of the VAP/CLABSI definition served as triggers. These included the use of VAP/CLABSI-related antibiotics, the presence of mechanical ventilation or an intravenous central line, and the presence of specific clinical symptoms. Triggers were automatically fired by the PDMS. Chest X-rays and microbiology culture results were checked only on patient days with a positive trigger signal from the ESS. In traditional screening, no triggers were used; therefore, chest X-rays and culture results had to be screened for all patient days of all included patients. Patients with pneumonia at admission were excluded.
Results
A total of 553 patients were screened for VAP and CLABSI. The incidence of VAP was 3.3/1,000 ventilation days (13 VAP/3,927 mechanical ventilation days), and the incidence of CLABSI was 1.7/1,000 central line days (24 CLABSI/13.887 central line days). For VAP, the trigger-based screening had a sensitivity of 92.3%, a specificity of 100%, and a negative predictive value of 99.8% compared to traditional screening of all patients. For CLABSI, sensitivity was 91.3%, specificity 100%, and negative predictive value 99.6%.
Conclusions
Pre-selection of patients to be checked for signs and symptoms of VAP and CLABSI by a computer-generated automated trigger system was time saving but slightly less accurate than conventional surveillance. However, this after-the-fact surveillance was mainly designed as a quality indicator over time rather than for precise determination of infection rates. Therefore, surveillance of VAP and CLABSI with a trigger-based ESS is feasible and effective.
doi:10.1186/s13613-014-0040-x
PMCID: PMC4303743  PMID: 25646148
Hospital-acquired infection (HAI); Quality improvement; Electronic surveillance system; Decision support capabilities; Infection prevention (IP); Patient data management system
9.  Development of trigger-based semi-automated surveillance of ventilator-associated pneumonia and central line-associated bloodstream infections in a Dutch intensive care 
Background
Availability of a patient data management system (PDMS) has created the opportunity to develop trigger-based electronic surveillance systems (ESSs). The aim was to evaluate a semi-automated trigger-based ESS for the detection of ventilator-associated pneumonia (VAP) and central line-associated blood stream infections (CLABSIs) in the intensive care.
Methods
Prospective comparison of surveillance was based on a semi-automated ESS with and without trigger. Components of the VAP/CLABSI definition served as triggers. These included the use of VAP/CLABSI-related antibiotics, the presence of mechanical ventilation or an intravenous central line, and the presence of specific clinical symptoms. Triggers were automatically fired by the PDMS. Chest X-rays and microbiology culture results were checked only on patient days with a positive trigger signal from the ESS. In traditional screening, no triggers were used; therefore, chest X-rays and culture results had to be screened for all patient days of all included patients. Patients with pneumonia at admission were excluded.
Results
A total of 553 patients were screened for VAP and CLABSI. The incidence of VAP was 3.3/1,000 ventilation days (13 VAP/3,927 mechanical ventilation days), and the incidence of CLABSI was 1.7/1,000 central line days (24 CLABSI/13.887 central line days). For VAP, the trigger-based screening had a sensitivity of 92.3%, a specificity of 100%, and a negative predictive value of 99.8% compared to traditional screening of all patients. For CLABSI, sensitivity was 91.3%, specificity 100%, and negative predictive value 99.6%.
Conclusions
Pre-selection of patients to be checked for signs and symptoms of VAP and CLABSI by a computer-generated automated trigger system was time saving but slightly less accurate than conventional surveillance. However, this after-the-fact surveillance was mainly designed as a quality indicator over time rather than for precise determination of infection rates. Therefore, surveillance of VAP and CLABSI with a trigger-based ESS is feasible and effective.
doi:10.1186/s13613-014-0040-x
PMCID: PMC4303743  PMID: 25646148
Hospital-acquired infection (HAI); Quality improvement; Electronic surveillance system; Decision support capabilities; Infection prevention (IP); Patient data management system
10.  Early high protein intake is associated with low mortality and energy overfeeding with high mortality in non-septic mechanically ventilated critically ill patients 
Critical Care  2014;18(6):701.
Introduction
Early protein and energy feeding in critically ill patients is heavily debated and early protein feeding hardly studied.
Methods
A prospective database with mixed medical-surgical critically ill patients with prolonged mechanical ventilation (>72 hours) and measured energy expenditure was used in this study. Logistic regression analysis was used to analyse the relation between admission day-4 protein intake group (with cutoffs 0.8, 1.0, and 1.2 g/kg), energy overfeeding (ratio energy intake/measured energy expenditure > 1.1), and admission diagnosis of sepsis with hospital mortality after adjustment for APACHE II (Acute Physiology and Chronic Health Evaluation II) score.
Results
A total of 843 patients were included. Of these, 117 had sepsis. Of the 736 non-septic patients 307 were overfed. Mean day-4 protein intake was 1.0 g/kg pre-admission weight per day and hospital mortality was 36%. In the total cohort, day-4 protein intake group (odds ratio (OR) 0.85; 95% confidence interval (CI) 0.73 to 0.99; P = 0.047), energy overfeeding (OR 1.62; 95%CI 1.07 to 2.44; P = 0.022), and sepsis (OR 1.77; 95%CI 1.18 to 2.65; P = 0.005) were independent risk factors for mortality besides APACHE II score. In patients with sepsis or energy overfeeding, day-4 protein intake was not associated with mortality. For non-septic, non-overfed patients (n = 419), mortality decreased with higher protein intake group: 37% for <0.8 g/kg, 35% for 0.8 to 1.0 g/kg, 27% for 1.0 to 1.2 g/kg, and 19% for ≥1.2 g/kg (P = 0.033). For these, a protein intake level of ≥1.2 g/kg was significantly associated with lower mortality (OR 0.42, 95%CI 0.21 to 0.83, P = 0.013).
Conclusions
In non-septic critically ill patients, early high protein intake was associated with lower mortality and early energy overfeeding with higher mortality. In septic patients early high protein intake had no beneficial effect on mortality.
Electronic supplementary material
The online version of this article (doi:10.1186/s13054-014-0701-z) contains supplementary material, which is available to authorized users.
doi:10.1186/s13054-014-0701-z
PMCID: PMC4279460  PMID: 25499096
11.  Draft Genome Sequence of Enterobacter cloacae Strain S611 
Genome Announcements  2014;2(6):e00710-14.
We report draft genomes of Enterobacter cloacae strain S611, an endophytic bacterium isolated from surface-sterilized germinating wheat seeds. We present the assembly and annotation of its genome, which may provide insights into the metabolic pathways involved in adaptation.
doi:10.1128/genomeA.00710-14
PMCID: PMC4263822  PMID: 25502660
12.  Outcome and Prognostic Factors for Patients Who Relapse After Allogeneic Stem Cell Transplantation 
SUMMARY
Disease relapse remains a major obstacle to the success of allogeneic hematopoietic stem cell transplantation (HSCT), yet little is known about the relevant prognostic factors after relapse. We studied 1080 patients transplanted between 2004 and 2008, among whom 351 relapsed. The 3-year post-relapse overall survival (prOS) was 19%. Risk factors for mortality after relapse included shorter time to relapse, higher disease risk index at HSCT, myeloablative conditioning, high pre-transplantation co-morbidity index, and graft-versus-host disease (GVHD) occurring prior to relapse. Important prognostic factors did not vary by disease type. Based on this, we could stratify patients into 3 groups, with 3-year prOS of 36%, 14% and 3% (p<0.0001). This score was validated in a historical cohort of 276 patients. Post-relapse donor lymphocyte infusion or repeat HSCT was associated with improved prOS, as was the development of GVHD after relapse. These differences remained significant in models that accounted for other prognostic factors and in landmark analyses of patients who survived at least 2 months from relapse. The results of this study may aid with prognostication and management of patients who relapse after HSCT, as well as motivate the design of clinical trials aimed at relapse prevention or treatment in the higher-risk patients.
doi:10.1016/j.bbmt.2013.09.011
PMCID: PMC3848699  PMID: 24076323
13.  Breakthrough cancer medicine and its impact on novel drug development in China: report of the US Chinese Anti-Cancer Association (USCACA) and Chinese Society of Clinical Oncology (CSCO) Joint Session at the 17th CSCO Annual Meeting 
Chinese Journal of Cancer  2014;33(12):620-624.
The US Chinese Anti-Cancer Association (USCACA) teamed up with Chinese Society of Clinical Oncology (CSCO) to host a joint session at the17th CSCO Annual Meeting on September 20th, 2014 in Xiamen, China. With a focus on breakthrough cancer medicines, the session featured innovative approaches to evaluate breakthrough agents and established a platform to interactively share successful experiences from case studies of 6 novel agents from both the United States and China. The goal of the session is to inspire scientific and practical considerations for clinical trial design and strategy to expedite cancer drug development in China. A panel discussion further provided in-depth advice on advancing both early and full development of novel cancer medicines in China.
doi:10.5732/cjc.014.10246
PMCID: PMC4308658  PMID: 25418191
Breakthrough; clinical trial; cancer medicine
14.  Sperm DNA and chromatin integrity in semen samples used for intrauterine insemination 
Background
Sperm DNA damage is associated with male infertility but whether normozoospermic infertile men also have DNA damage is unknown.
Objective
To evaluate sperm DNA and chromatin integrity in men with mild male factor infertility.
Design, setting and participants
Prospective study of 102 consecutive men (78 normozoospermic, 15 asthenozoospermic, 9 oligozoospermic) enrolled for intrauterine insemination (IUI) and 15 fertile controls.
Outcome measurements and statistical analysis
Standard semen parameters and sperm chromatin and DNA integrity were assessed and compared between groups. Sperm chromatin quality was assessed by (1) aniline blue staining (AB is specific to histone lysines), (2) iodoacetamide fluorescein fluorescence (IAF targets free protamine sulfhydryl groups) and (3) sperm chromatin structure assay (SCSA) with the results expressed as % DNA fragmentation index (%DFI).
Results and limitations
The mean (±SD) percentage of spermatozoa with positive IAF fluorescence was significantly higher in the IUI population compared to fertile controls (17 % ± 10 % vs. 8 % ± 6 %, P = 0.0011) and also in the normozoospermic subset (n = 78) compared to controls (16 % ± 9 % vs. 8 % ± 6 %, P < 0.0001, ANOVA). We also observed a trend toward lower %progressive motility, and higher %AB staining and %DFI in the IUI group compared to controls. We observed significant relationships between sperm %DFI and progressive motility (r = −0.40, P < 0.0001) and between positive AB staining and IAF fluorescence (r = 0.58, P < 0.0001).
Conclusions
The data indicate that sperm chromatin integrity may be abnormal in men enrolled in IUI treatment cycles, despite the fact that most of these men are normozoospermic.
doi:10.1007/s10815-013-0101-3
PMCID: PMC3879931  PMID: 24068511
Sperm DNA; Intrauterine insemination; Male infertility; Normozoospermia; Semen; Sperm chromatin
15.  Granulocyte-Colony Stimulating Factor Related Pathways Tested on an Endometrial Ex-Vivo Model 
PLoS ONE  2014;9(10):e102286.
Introduction
Recombinant human Granulocyte-Colony Stimulating Factor (rhG-CSF) supplementation seems to be a promising innovative therapy in reproductive medicine, used in case of recurrent miscarriage, embryo implantation failure or thin endometrium, although its mechanisms of action remain unknown. Our aim was to identify possible endometrial pathways influenced by rhG-CSF.
Materials and Methods
Hypothetical molecular interactions regulated by G-CSF were designed through a previous large scale endometrial microarray study. The variation of endometrial expression of selected target genes was confirmed in control and infertile patients. G-CSF supplementation influence on these targets was tested on an endometrial ex-vivo culture. Middle luteal phase endometrial biopsies were cultured on collagen sponge with or without rhG-CSF supplementation during 3 consecutive days. Variations of endometrial mRNA expression for the selected targets were studied by RT-PCR.
Results
At the highest dose of rhG-CSF stimulation, the mRNA expression of these selected target genes was significantly increased if compared with their expression without addition of rhG-CSF. The selected targets were G-CSF Receptor (G-CSFR), Integrin alpha-V/beta-3 (ITGB3) implicated in cell migration and embryo implantation, Plasminogen Activator Urokinase Receptor (PLAUR) described as interacting with integrins and implicated in cell migration, Thymidine Phosphorylase (TYMP) implicated in local angiogenesis, CD40 and its ligand CD40L involved in cell proliferation control.
Conclusion
RhG-CSF seems able to influence endometrial expressions crucial for implantation process involving endometrial vascular remodelling, local immune modulation and cellular adhesion pathways. These variations observed in an ex-vivo model should be tested in-vivo. The strict indications or counter indication of rhG-CSF supplementation in reproductive field are not yet established, while the safety of its administration in early pregnancy on early embryogenesis still needs to be demonstrated. Nevertheless, rhG-CSF appears as a promising therapy in some difficult and unsolved cases of reproductive failure. Indications of pre-conceptual rhG-CSF supplementation may derive from a diagnosed lack of endometrial expression of some target genes.
doi:10.1371/journal.pone.0102286
PMCID: PMC4183482  PMID: 25275446
16.  Overcoming cross-gender differences and challenges in Le Fort-based, craniomaxillofacial transplantation with enhanced computer-assisted technology 
Annals of plastic surgery  2013;71(4):421-428.
Background
Gender-specific anthropometrics, skin texture/adnexae mismatch, and social apprehension have prevented cross-gender facial transplantation from evolving. However, the scarce donor pool and extreme waitlist times are currently suboptimal. Our objective was to: 1) perform and assess cadaveric facial transplantation for each gender-mismatch scenario employing virtual panning with cutting guide fabrication and 2) review the advantages/disadvantages of cross-gender facial transplantation.
Methods
Cross-gender facial transplantation feasibility was evaluated through two mock, double-jaw, Le Fort-based cadaveric allotransplants, including female donor-to-male recipient (T1-FM) and male donor-to-female recipient (T2-MF). Hybrid facial-skeletal relationships were investigated using cephalometric measurements, including sellion-nasion-A point (SNA) and sellion-nasion-B point (SNB) angles, and lower-anterior-facial-height to total-anterior-facial-height ratio (LAFH/TAFH). Donor and recipient cutting guides were designed with virtual planning based on our team’s experience in swine dissections and used to optimize the results.
Results
Skeletal proportions and facial-aesthetic harmony of the transplants [n=2] were found to be equivalent to all reported experimental/clinical gender-matched cases by using custom guides and Mimics technology. Cephalometric measurements are shown in Table 1 relative to Eastman Normal Values.
Conclusions
Based on our results, we believe that cross-gender facial transplantation can offer equivalent, anatomical skeletal outcomes to those of gender-matched pairs using pre-operative planning and custom guides for execution. Lack of literature discussion of cross-gender facial transplantation highlights the general stigmata encompassing the subject. We hypothesize that concerns over gender-specific anthropometrics, skin texture/adnexae disparity, and increased immunological resistance have prevented full acceptance thus far. Advantages include an increased donor pool with expedited reconstruction, as well as size-matched donors.
doi:10.1097/SAP.0b013e3182a0df45
PMCID: PMC3775652  PMID: 24025655
Face Transplant; Craniomaxillofacial; Vascularized Composite Allotransplantation (VCA); Gender; Cross-gender; Intraoperative Cutting Guide
17.  Evaluation of NHS Carbamates as a Potent and Selective Class of Endocannabinoid Hydrolase Inhibitors 
ACS Chemical Neuroscience  2013;4(9):1322-1332.
Monoacylglycerol lipase (MAGL) is a principal metabolic enzyme responsible for hydrolyzing the endogenous cannabinoid (endocannabinoid) 2-arachidonoylglycerol (2-AG). Selective inhibitors of MAGL offer valuable probes to further understand the enzyme’s function in biological systems and may lead to drugs for treating a variety of diseases, including psychiatric disorders, neuroinflammation, and pain. N-Hydroxysuccinimidyl (NHS) carbamates have recently been identified as a promising class of serine hydrolase inhibitors that shows minimal cross-reactivity with other proteins in the proteome. Here, we explore NHS carbamates more broadly and demonstrate their potential as inhibitors of endocannabinoid hydrolases and additional enzymes from the serine hydrolase class. We extensively characterize an NHS carbamate 1a (MJN110) as a potent, selective, and in-vivo-active MAGL inhibitor. Finally, we demonstrate that MJN110 alleviates mechanical allodynia in a rat model of diabetic neuropathy, marking NHS carbamates as a promising class of MAGL inhibitors.
doi:10.1021/cn400116z
PMCID: PMC3778430  PMID: 23731016
activity-based protein profiling; 2-arachidonoyl glycerol; carbamate; endocannabinoid; inhibitor; click chemistry; monoacylglycerol lipase
18.  Streptococcus pneumoniae Translocates into the Myocardium and Forms Unique Microlesions That Disrupt Cardiac Function 
PLoS Pathogens  2014;10(9):e1004383.
Hospitalization of the elderly for invasive pneumococcal disease is frequently accompanied by the occurrence of an adverse cardiac event; these are primarily new or worsened heart failure and cardiac arrhythmia. Herein, we describe previously unrecognized microscopic lesions (microlesions) formed within the myocardium of mice, rhesus macaques, and humans during bacteremic Streptococcus pneumoniae infection. In mice, invasive pneumococcal disease (IPD) severity correlated with levels of serum troponin, a marker for cardiac damage, the development of aberrant cardiac electrophysiology, and the number and size of cardiac microlesions. Microlesions were prominent in the ventricles, vacuolar in appearance with extracellular pneumococci, and remarkable due to the absence of infiltrating immune cells. The pore-forming toxin pneumolysin was required for microlesion formation but Interleukin-1β was not detected at the microlesion site ruling out pneumolysin-mediated pyroptosis as a cause of cell death. Antibiotic treatment resulted in maturing of the lesions over one week with robust immune cell infiltration and collagen deposition suggestive of long-term cardiac scarring. Bacterial translocation into the heart tissue required the pneumococcal adhesin CbpA and the host ligands Laminin receptor (LR) and Platelet-activating factor receptor. Immunization of mice with a fusion construct of CbpA or the LR binding domain of CbpA with the pneumolysin toxoid L460D protected against microlesion formation. We conclude that microlesion formation may contribute to the acute and long-term adverse cardiac events seen in humans with IPD.
Author Summary
Hospitalization for community-acquired pneumonia carries a documented risk for adverse cardiac events. These occur during infection and contribute to elevated mortality rates in convalescent individuals up to 1 year thereafter. We describe a previously unrecognized pathogenic mechanism by which Streptococcus pneumoniae, the leading cause of community-acquired pneumonia, causes direct cardiotoxicity and forms microscopic bacteria-filled lesions within the heart. Microlesions were detected in experimentally infected mice and rhesus macaques, as well as in heart sections from humans who succumbed to invasive pneumococcal disease (IPD). Cardiac microlesion formation required interaction of the bacterial adhesin CbpA with host Laminin receptor and bacterial cell wall with Platelet-activating factor receptor. Microlesion formation also required the pore-forming toxin pneumolysin. When infected mice were rescued with antibiotics, we observed robust signs of collagen deposition at former lesion sites. Thus, microlesions and the scarring that occurs thereafter may explain why adverse cardiac events occur during and following IPD.
doi:10.1371/journal.ppat.1004383
PMCID: PMC4169480  PMID: 25232870
19.  T-Plastin Expression Downstream to the Calcineurin/NFAT Pathway Is Involved in Keratinocyte Migration 
PLoS ONE  2014;9(9):e104700.
Cutaneous wound healing requires keratinocyte proliferation, migration and differentiation to restore the barrier function of the skin. The calcineurin/nuclear factor of activated-T-cell (NFAT) signaling pathway has been recently shown to be involved in keratinocyte growth, differentiation and migration. It is induced by an increased intracellular calcium rate and its inhibition results in decreased capacities of keratinocytes to migrate. Nevertheless, the link between calcineurin activation and keratinocyte migration remains unknown. Recently, Orai1, a pore subunit of a store-operated calcium channel that favors calcium influx, was shown to play a critical role to control proliferation and migration of basal keratinocytes. Of interest, the actin-bundling T-plastin is crucial in cell motility through cross-linking to actin filament and its synthesis was shown to be induced by calcium influx and regulated by the calcineurin/NFAT pathway in tumor Sezary cells. We investigated herein the role of the calcineurin/NFAT pathway-dependent T-plastin in keratinocyte migration, by quantifying T-plastin expression in keratinocytes and by analyzing their migration under calcineurin inhibition or knockdown of NFAT2 or T-plastin. We did confirm the role of the calcineurin/NFAT pathway in keratinocyte migration as shown by their decreased capacities to migrate after FK506 treatment or siNFAT2 transfection in both scratching and Boyden assays. The expression of NFAT2 and T-plastin in keratinocytes was decreased under FK506 treatment, suggesting that T-plastin plays a role in keratinocyte migration downstream to the calcineurin/NFAT pathway. Accordingly, siRNA knockdown of T-plastin expression also decreased their migration capacities. Actin lamellipodia formation as well as FAK and β6-integrin expression were also significantly decreased after treatment with FK506 or siRNA, reinforcing that NFAT2-dependent T-plastin expression plays a role in keratinocyte migration. These results indicate that T-plastin might be considered as a major actor in the mechanisms underlying calcineurin/NFAT-dependent keratinocyte migration and may explain wound-healing defects observed in patients under calcineurin inhibitor long-term treatment.
doi:10.1371/journal.pone.0104700
PMCID: PMC4165579  PMID: 25226517
20.  Evaluation of a standardized treatment regimen of anti-tuberculosis drugs for patients with multi-drug-resistant tuberculosis (STREAM): study protocol for a randomized controlled trial 
Trials  2014;15(1):353.
Background
In contrast to drug-sensitive tuberculosis, the guidelines for the treatment of multi-drug-resistant tuberculosis (MDR-TB) have a very poor evidence base; current recommendations, based on expert opinion, are that patients should be treated for a minimum of 20 months. A series of cohort studies conducted in Bangladesh identified a nine-month regimen with very promising results. There is a need to evaluate this regimen in comparison with the currently recommended regimen in a randomized controlled trial in a variety of settings, including patients with HIV-coinfection.
Methods/Design
STREAM is a multi-centre randomized trial of non-inferiority design comparing a nine-month regimen to the treatment currently recommended by the World Health Organization in patients with MDR pulmonary TB with no evidence on line probe assay of fluoroquinolone or kanamycin resistance. The nine-month regimen includes clofazimine and high-dose moxifloxacin and can be extended to 11 months in the event of delay in smear conversion. The primary outcome is based on the bacteriological status of the patients at 27 months post-randomization. Based on the assumption that the nine-month regimen will be slightly more effective than the control regimen and, given a 10% margin of non-inferiority, a total of 400 patients are required to be enrolled. Health economics data are being collected on all patients in selected sites.
Discussion
The results from the study in Bangladesh and cohorts in progress elsewhere are encouraging, but for this regimen to be recommended more widely than in a research setting, robust evidence is needed from a randomized clinical trial. Results from the STREAM trial together with data from ongoing cohorts should provide the evidence necessary to revise current recommendations for the treatment for MDR-TB.
Trial registration
This trial was registered with clincaltrials.gov (registration number: ISRCTN78372190) on 14 October 2010.
doi:10.1186/1745-6215-15-353
PMCID: PMC4164715  PMID: 25199531
Multi-drug-resistant tuberculosis; Multicenter randomized trial; Non-inferiority; Shorter treatment duration
21.  Dihydroquinazolinone Inhibitors of Proliferation of Blood and Liver Stage Malaria Parasites 
Drugs that target both the liver and blood stages of malaria will be needed to reduce the disease's substantial worldwide morbidity and mortality. Evaluation of a 259-member library of compounds that block proliferation of the blood stage of malaria revealed several scaffolds—dihydroquinazolinones, phenyldiazenylpyridines, piperazinyl methyl quinolones, and bis-benzimidazoles—with promising activity against the liver stage. Focused structure-activity studies on the dihydroquinazolinone scaffold revealed several molecules with excellent potency against both blood and liver stages. One promising early lead with dual activity is 2-(p-bromophenyl)-3-(2-(diethylamino)ethyl)-2,3-dihydroquinazolin-4(1H)-one with 50% effective concentrations (EC50s) of 0.46 μM and 0.34 μM against liver stage Plasmodium berghei ANKA and blood stage Plasmodium falciparum 3D7 parasites, respectively. Structure-activity relationships revealed that liver stage activity for this compound class requires a 3-dialkyl amino ethyl group and is abolished by substitution at the ortho-position of the phenyl moiety. These compounds have minimal toxicity to mammalian cells and are thus attractive compounds for further development.
doi:10.1128/AAC.02148-13
PMCID: PMC3957893  PMID: 24366746
22.  Detection of disease-associated α-synuclein in the cerebrospinal fluid: a feasibility study  
Clinical Neuropathology  2014;33(5):329-334.
With the aim to evaluate the significance and reliability of detecting disease-specific α-synuclein in the cerebrospinal fluid (CSF) we developed an ELISA and bead-assay. We used a commercial antibody (5G4) that does not bind to the physiological monomeric form of α-synuclein, but is highly specific for the disease-associated forms, including high molecular weight fraction of β-sheet rich oligomers. We applied both tests in CSF from a series of neuropathologically confirmed α-synucleinopathy cases, including Parkinson’s disease dementia (PDD) and dementia with Lewy bodies (DLB) (n = 7), as well as Alzheimer’s disease (n = 6), and control patients without neurodegenerative pathologies (n = 9). Disease-specific α-synuclein was detectable in the CSF in a subset of patients with α-synuclein pathology in the brain. When combined with the analysis of total α-synuclein, the bead-assay for disease-specific α-synuclein was highly specific for PDD/DLB. Detection of disease-associated α-synuclein combined with the total levels of α-synuclein is a promising tool for the in-vivo diagnosis of α-synucleinopathies, including PDD and LBD.
doi:10.5414/NP300796
PMCID: PMC4151342  PMID: 25131945
α-synuclein; bead-assay; cerebrospinal fluid; Parkinson’s disease dementia; dementia with Lewy bodies; synucleinopathy
23.  Diabetic Nephropathy for the Primary Care Provider: New Understandings on Early Detection and Treatment 
The Ochsner Journal  2014;14(3):369-379.
Background
Diabetic nephropathy is the leading cause of renal disease in the United States, occurring in 20%-40% of patients with diabetes. This condition is a distinct manifestation of diabetic renal disease seen in patients with type 1 and type 2 diabetes. Despite clear screening and management recommendations, diabetic nephropathy remains substantially underdiagnosed.
Methods
This review presents recent guidelines and recommendations from varied work groups to identify, monitor, and halt the progression of diabetic nephropathy. Our search of the recent literature focused on diagnostic criteria, the latest screening recommendations, novel screening methods, current research, new treatment recommendations, and goals for early intervention.
Results
Current recommendations for early detection and treatment of diabetic nephropathy include yearly albumin to creatinine ratio checks and more frequent tests if indicated based on glomerular filtration rate and albuminuria; optimizing glucose control with a target hemoglobin A1c goal of <7%; initiating angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) as the first line in disease management with dual therapy of ACE inhibitors and ARBs no longer recommended; managing blood pressure with a goal of <140/90 mmHg as the target for all patients with diabetes; and initiating statin therapy for patients <50 years old and with concomitant chronic kidney disease and diabetes and in all patients with chronic kidney disease >50 years of age regardless of the coexistence of diabetes.
Conclusion
With early detection, proper screening, and management, the impact of diabetic nephropathy may be better mitigated to lessen its impact on society and healthcare.
PMCID: PMC4171795  PMID: 25249803
Albuminuria; diabetes mellitus; diabetic nephropathies; early diagnosis; primary health care; renal insufficiency–chronic
24.  Citrate anticoagulation versus systemic heparinisation in continuous venovenous hemofiltration in critically ill patients with acute kidney injury: a multi-center randomized clinical trial 
Critical Care  2014;18(4):472.
Introduction
Because of ongoing controversy, renal and vital outcomes are compared between systemically administered unfractionated heparin and regional anticoagulation with citrate-buffered replacement solution in predilution mode, during continuous venovenous hemofiltration (CVVH) in critically ill patients with acute kidney injury (AKI).
Methods
In this multi-center randomized controlled trial, patients admitted to the intensive care unit requiring CVVH and meeting inclusion criteria, were randomly assigned to citrate or heparin. Primary endpoints were mortality and renal outcome in intention-to-treat analysis. Secondary endpoints were safety and efficacy. Safety was defined as absence of any adverse event necessitating discontinuation of the assigned anticoagulant. For efficacy, among other parameters, survival times of the first hemofilter were studied.
Results
Of the 139 patients enrolled, 66 were randomized to citrate and 73 to heparin. Mortality rates at 28 and 90 days did not differ between groups: 22/66 (33%) of citrate-treated patients died versus 25/72 (35%) of heparin-treated patients at 28 days, and 27/65 (42%) of citrate-treated patients died versus 29/69 (42%) of heparin-treated patients at 90 days (P = 1.00 for both). Renal outcome, i.e. independency of renal replacement therapy 28 days after initiation of CVVH in surviving patients, did not differ between groups: 29/43 (67%) in the citrate-treated patients versus 33/47 (70%) in heparin-treated patients (P = 0.82). Heparin was discontinued in 24/73 (33%) of patients whereas citrate was discontinued in 5/66 (8%) of patients (P < 0.001). Filter survival times were superior for citrate (median 46 versus 32 hours, P = 0.02), as were the number of filters used (P = 0.002) and the off time within 72 hours (P = 0.002). The costs during the first 72 hours of prescribed CVVH were lower in citrate-based CVVH.
Conclusions
Renal outcome and patient mortality were similar for citrate and heparin anticoagulation during CVVH in the critically ill patient with AKI. However, citrate was superior in terms of safety, efficacy and costs.
Trial registration
Clinicaltrials.gov NCT00209378. Registered 13th September 2005.
Electronic supplementary material
The online version of this article (doi:10.1186/s13054-014-0472-6) contains supplementary material, which is available to authorized users.
doi:10.1186/s13054-014-0472-6
PMCID: PMC4161888  PMID: 25128022
25.  Effect of intensive treatment of hyperglycemia on microvascular complications of type 2 diabetes in ACCORD: a randomized trial 
Lancet  2010;376(9739):419-430.
Design
ACCORD is a parallel group, randomized trial designed to investigate whether intensive glycemic therapy with a target HbA1c of <6.0% versus standard therapy with a target of 7.0 to 7.9% reduces cardiovascular disease (CVD) morbidity, mortality, and microvascular complications in participants with type 2 diabetes.
Methods
Volunteers with established type 2 diabetes, HbA1c levels ≥ 7.5% and CVD or two or more CVD risk factors were recruited at 77 clinical sites across the U.S. and Canada. Instructional materials, behavioral counseling, glucose-lowering medications and self-monitoring supplies were provided by the study. Therapeutic regimens were individualized on the basis of randomized assignment and response to therapy. This investigation examines the effect of treatment to glycemic goals on occurrence of microvascular diabetes complications. Prespecified composite outcomes were: 1) dialysis or renal transplantation, or serum creatinine >291.7 micromol/L, or retinal photocoagulation or vitrectomy, and 2) these plus peripheral neuropathy. Thirteen prespecified secondary measures of kidney, eye, and peripheral nerve function were also evaluated. Randomization was performed at clinical sites using a central randomization routine available on the study website. Both investigators and participants were unmasked to treatment arm assignment.
Results
A total of 10,251 participants were randomized (5,128 intensive and 5,123 standard) between January, 2001 and October, 2005. This analysis includes 10,234 patients (5,107 intensive and 5,108 standard). Intensive therapy was stopped before study end due to increased mortality, and patients were transitioned to standard therapy. Outcomes are reported at transition and at study end. At transition, the first composite outcome occurred in 443/5107 and 444/5108 participants in the intensive and standard arms, respectively (p= 0.99), and the second outcome in 1591/5107 and 1659/5108 participants in intensive and standard arms (p=0.20). Results were similar at study end. Secondary measures at study end favoring intensive therapy (p<0.05) included development of macroalbuminuria, cataract extraction, visual acuity, a score of >2.0 on the Michigan Neuropathy Screening Instrument, loss of ankle jerk and light touch.
Conclusions
Intensive glycemic treatment did not reduce the risk of advanced measures of microvascular outcomes, but delayed the onset of macroalbuminuria and some measures of eye complications and neuropathy. These benefits must be weighed against the increase in total and CVD-related mortality, increased weight gain, and higher risk for severe hypoglycemia.
doi:10.1016/S0140-6736(10)60576-4
PMCID: PMC4123233  PMID: 20594588

Results 1-25 (472)