Human Kinase IGF1R/IR Inhibitor Linsitinib Controls the In Vitro and Intracellular Growth of Mycobacterium tuberculosis.

ATP provides energy in the biosynthesis of cellular metabolites as well as regulates protein functions through phosphorylation. Many ATP-dependent enzymes are antibacterial and anticancer targets including human kinases acted on by most of the successful drugs. In search of new chemotherapeutics for tuberculosis (TB), we screened repurposing compounds against the essential glutamine synthase (GlnA1) of Mycobacterium tuberculosis (Mtb) and identified linsitinib, a clinical-stage drug originally targeting kinase IGF1R/IR as a potent GlnA1 inhibitor. Linsitinib has direct antimycobacterial activity. Biochemical, molecular modeling, and target engagement analyses revealed the inhibition is ATP-competitive and specific in Mtb. Linsitinib also improves autophagy flux in both Mtb-infected and uninfected THP1 macrophages, as demonstrated by the decreased p-mTOR and p62 and the increased lipid-bound LC3B-II and autophagosome forming puncta. Linsitinib-mediated autophagy reduces intracellular growth of wild-type and isoniazid-resistant Mtb alone or in combination with bedaquiline. We have demonstrated that an IGF-IR/IR inhibitor can potentially be used to treat TB. Our study reinforces the concept of targeting ATP-dependent enzymes for novel anti-TB therapy.

Effectiveness of a nongovernmental organization-led large-scale community atrial fibrillation screening program using the smartphone electrocardiogram: An observational cohort study.

BACKGROUND: Opportunistic screening for atrial fibrillation (AF) in patients older than 65 years is currently recommended. OBJECTIVE: We aim to examine the effectiveness of a nongovernmental organization-led community-based AF screening program carried out by trained layperson volunteers. METHODS: AF screening was performed using a smartphone electrocardiogram in 11,574 participants. RESULTS: Among all participants, smartphone electrocardiograms were interpretable in 10,735 citizens (92.8%; 8564 female citizens [79.8%]; mean age 78.6 ± 8.1 years). Two hundred forty-four participants (2.3%; 95% confidence interval [CI] 2-2.6%; 172 female participants [70.5%]; mean age 79.5 ± 7.9 years) had AF and were advised over phone by a nurse to seek medical attention. Newly diagnosed AF was found in 74 participants (0.69%; 95% CI 0.54-0.84%) with a mean CHA2DS2-VASc score of 3.9 ± 1.5. Thirty-six of them (48%; 95% CI 36.6-59.4%) were asymptomatic. The number needed to screen for 1 newly diagnosed AF was 145. Telephone follow-up of participants with AF was conducted 9 months after screening. Of 72 participants with newly diagnosed AF and indicated for oral anticoagulation, 47 (65.3%; 95% CI 54.3-76.3%) sought medical attention, 17 (23.6%; 95% CI 13.8-33.4%) received oral anticoagulants, and 16 (22.2%; 95% CI 12.6-31.8%) had 100% compliance. The number needed to screen for 1 appropriately treated newly diagnosed AF was 671. CONCLUSION: This nongovernmental organization-led community-based AF screening program is effective in identifying citizens with newly diagnosed AF. However, the effectiveness of the program in subsequently leading them to receive appropriate oral anticoagulation therapy is weakened by the lack of a more structured downstream management pathway.

Determinants of tolerance to inhibitors in hardwood spent sulfite liquor in genome shuffled Pachysolen tannophilus strains.

Genome shuffling was used to obtain Pachysolen tannophilus mutants with improved tolerance to inhibitors in hardwood spent sulfite liquor (HW SSL). Genome shuffled strains (GHW301, GHW302 and GHW303) grew at higher concentrations of HW SSL (80 % v/v) compared to the HW SSL UV mutant (70 % v/v) and the wild-type (WT) strain (50 % v/v). In defined media containing acetic acid (0.70-0.90 % w/v), GHW301, GHW302 and GHW303 exhibited a shorter lag compared to the acetic acid UV mutant, while the WT did not grow. Genome shuffled strains produced more ethanol than the WT at higher concentrations of HW SSL and an aspen hydrolysate. To identify the genetic basis of inhibitor tolerance, whole genome sequencing was carried out on GHW301, GHW302 and GHW303 and compared to the WT strain. Sixty single nucleotide variations were identified that were common to all three genome shuffled strains. Of these, 40 were in gene sequences and 20 were within 5 bp-1 kb either up or downstream of protein encoding genes. Based on the mutated gene products, mutations were grouped into functional categories and affected a variety of cellular functions, demonstrating the complexity of inhibitor tolerance in yeast. Sequence analysis of UV mutants (UAA302 and UHW303) from which GHW301, GHW302 and GHW303 were derived, confirmed the success of our cross-mating based genome shuffling strategy. Whole-genome sequencing analysis allowed identification of potential gene targets for tolerance to inhibitors in lignocellulosic hydrolysates.

Comparative analysis of genes regulated by Dzip1/iguana and hedgehog in zebrafish.

BACKGROUND: The zebrafish genetic mutant iguana (igu) has defects in the ciliary basal body protein Dzip1, causing improper cilia formation. Dzip1 also interacts with the downstream transcriptional activators of Hedgehog (Hh), the Gli proteins, and Hh signaling is disrupted in igu mutants. Hh governs a wide range of developmental processes, including stabilizing developing blood vessels to prevent hemorrhage. Using igu mutant embryos and embryos treated with the Hh pathway antagonist cyclopamine, we conducted a microarray to determine genes involved in Hh signaling mediating vascular stability. RESULTS: We identified 40 genes with significantly altered expression in both igu mutants and cyclopamine-treated embryos. For a subset of these, we used in situ hybridization to determine localization during embryonic development and confirm the expression changes seen on the array. CONCLUSIONS: Through comparing gene expression changes in a genetic model of vascular instability with a chemical inhibition of Hh signaling, we identified a set of 40 differentially expressed genes with potential roles in vascular stabilization.

Transcriptional profiling of Saccharomyces cerevisiae T2 cells upon exposure to hardwood spent sulphite liquor: comparison to acetic acid, furfural and hydroxymethylfurfural.

Global gene expression was analyzed in Saccharomyces cerevisiae T2 cells grown in the presence of hardwood spent sulphite liquor (HW SSL) and each of the three main inhibitors in HW SSL, acetic acid, hydroxymethyfurfural (HMF) and furfural, using a S. cerevisiae DNA oligonucleotide microarray. The objective was to compare the gene expression profiles of T2 cells in response to the individual inhibitors against that elicited in response to HW SSL. Acetic acid mainly affected the expression of genes related to the uptake systems of the yeast as well as energy generation and metabolism. Furfural and HMF mainly affected the transcription of genes involved in the redox balance of the cell. On the other hand, the effect of HW SSL on S. cerevisiae T2 cells was distinct and considerably more diverse as compared to the effect of individual inhibitors found in lignocellulosic hydrolysates. This is not surprising as HW SSL contains a complex mixture of inhibitors which may act synergistically. HW SSL elicited significant changes in expression of genes involved in diverse and multiple effects on several aspects of the cellular structure and function. A notable response to HW SSL was decreased expression of the ribosomal protein genes in T2 cells. In addition, HW SSL decreased the expression of genes functioning in the synthesis and transport of proteins as well as metabolism of carbohydrates, lipids, vitamins and vacuolar proteins. Furthermore, the expression of genes involved in multidrug resistance, iron transport and pheromone response was increased, suggesting that T2 cells grown in the presence of HW SSL may have activated pheromone response and/or activated pleiotropic drug response. Some of the largest changes in gene expression were observed in the presence of HW SSL and the affected genes are involved in mating, iron transport, stress response and phospholipid metabolism. A total of 59 out of the 400 genes differentially expressed in the presence of HW SSL, acetic acid, HMF and furfural, belonged to the category of poorly characterized genes. The results indicate that transcriptional responses to individual lignocellulosic inhibitors gave a different picture and may not be representative of how the cells would respond to the presence of all the inhibitors in lignocellulosic hydrolysates such as HW SSL.

Chronic total occlusion intervention: a novel antegrade guidewire probing technique.

We reported a case of successful recanalization of a left anterior descending (LAD) artery chronic total occlusion (CTO) with 'integrate guidewire probing technique.' After we mistakenly deployed a stent at the proximal LAD from left main (LM) into a diagonal branch across the mid LAD, this mid LAD CTO became further jailed under the stent. Antegrade wiring of this CTO lesion became exceptionally difficult. After several unsuccessful attempts with different guidewires and interventional techniques, we placed a retrograde microcatheter into the CTO lesion with its tip just situated at the stent strut. An antegrade guidewire supported by another microcatheter was targeted at the tip of the retrograde microcatheter and successfully crossed the CTO lesion. The LAD was successfully recanalized. This technique appeared to be feasible and safe to facilitate antegrade wire crossing of the CTO lesion.

"Sepal wire technique"--a novel technique for aorto-ostial left main stenting.

Aorto-ostial left main (LM) percutaneous coronary intervention (PCI) remains a challenge in interventional cardiology, as precise positioning of stents using conventional angiographic landmarks is difficult. Previously described techniques either involve the use of additional complex steps or commercially available special devices that carry extra costs. We describe a novel technique for ostial LM stent positioning that makes use of a simple additional workhorse wire curling back into the aorta like the sepal of a flower.

Sibutramine-induced acute myocardial infarction in a young lady.

INTRODUCTION: Sibutramine is an amphetamine-like drug used for its weight reducing effect. Sibutramine-induced acute coronary syndrome has rarely been reported. We report a case of myocardial infarction associated with the use of sibutramine. CASE REPORT: A 37-year-old woman presented to an Emergency Department (ED) with intermittent retrosternal chest pain, nausea, and sweating for 3 days. She reported taking one sibutramine tablet each day for 3 days. Blood pressure was 128/89 mm Hg and pulse 66 beats/min. An electrocardiogram revealed ST elevation over the inferior leads and ST depression over leads AVR and V1, the other leads were normal. Serum troponin T was 0.65 microg/L, and sibutramine was identified in her urine. Echocardiography revealed mild hypokinesia over the inferior wall without evidence of acute aortic dissection. The ST segment changes resolved spontaneously within 24 h of cardiac care unit (CCU) admission, a coronary angiogram performed 1 week later was unremarkable, and echocardiography performed 4 weeks after the event showed normal resting regional wall motion. DISCUSSION: Seventeen medications containing sibutramine as an active ingredient were registered in Hong Kong in 2007. Sibutramine was introduced in the United States in 1997 and in Australia, United Kingdom, and Italy in 2001. Hypertension, tachycardia, dry mouth, and headache are the most commonly reported adverse reactions. Cardiovascular toxicities include tachycardia, palpitation, hypertension, and tachyarrhythmia. CONCLUSIONS: We postulate that the myocardial infarction was the result of coronary vasospasm associated with the therapeutic use of sibutramine-containing slimming pills.

Isolated tumor cells and circulating CK20 mRNA in pN0 colorectal cancer patients.

Micrometastases in lymph nodes and blood may provide important prognostic information. In this study, cytokeratin 20 (CK20) positive cells in lymph nodes and circulating CK20 mRNA were studied using 57 paraffin-embedded lymph node specimens and blood from 24 patients with pN0 colorectal cancer (CRC), respectively. Results showed that 29 out of 56 (52%) lymph node specimens had CK20-positive cells (range: 1-35). Follow-up of the patients for 12 months indicated that 4 patients (7%) had CRC metastases to liver, lung, and bone. In addition, 8 out of 24 (33%) samples had at least 2-fold circulating CK20 mRNA expression higher than the pooled normal sample. This study provides evidence that CK20-positive cells were found in the lymph nodes and differentially expressed circulating CK20 mRNA was also detected in the blood from patients with pN0 CRC. Long-term follow-up is necessary to study their prognostic use in patients with non-metastatic CRC.

Systematic validation and atomic force microscopy of non-covalent short oligonucleotide barcode microarrays.

BACKGROUND: Molecular barcode arrays provide a powerful means to analyze cellular phenotypes in parallel through detection of short (20-60 base) unique sequence tags, or "barcodes", associated with each strain or clone in a collection. However, costs of current methods for microarray construction, whether by in situ oligonucleotide synthesis or ex situ coupling of modified oligonucleotides to the slide surface are often prohibitive to large-scale analyses. METHODOLOGY/PRINCIPAL FINDINGS: Here we demonstrate that unmodified 20mer oligonucleotide probes printed on conventional surfaces show comparable hybridization signals to covalently linked 5'-amino-modified probes. As a test case, we undertook systematic cell size analysis of the budding yeast Saccharomyces cerevisiae genome-wide deletion collection by size separation of the deletion pool followed by determination of strain abundance in size fractions by barcode arrays. We demonstrate that the properties of a 13K unique feature spotted 20 mer oligonucleotide barcode microarray compare favorably with an analogous covalently-linked oligonucleotide array. Further, cell size profiles obtained with the size selection/barcode array approach recapitulate previous cell size measurements of individual deletion strains. Finally, through atomic force microscopy (AFM), we characterize the mechanism of hybridization to unmodified barcode probes on the slide surface. CONCLUSIONS/SIGNIFICANCE: These studies push the lower limit of probe size in genome-scale unmodified oligonucleotide microarray construction and demonstrate a versatile, cost-effective and reliable method for molecular barcode analysis.

Evaluation of the Morse Fall Scale: applicability in Chinese hospital populations.

BACKGROUND: Patient falls have been identified as a significant health problem in the general hospital patient population. The Morse Fall Scale (MFS) is an individualized criterion-referenced assessment tool designed for measuring the likelihood of patient falls in hospitals. Despite the scale has demonstrated high validity and reliability in the previous researches, this study is to provide additional validity tests to determine the applicability in the Chinese hospital population. OBJECTIVES: To examine the predictive power of the MFS to predict patient falls. To conduct reliability tests on internal consistency, item analysis, inter-rater and test-retest reliability. DESIGN: The study was a cross-sectional study. SETTINGS: The medical and geriatric units of three rehabilitation hospitals in Hong Kong participated in the study. PARTICIPANTS: A convenience sample of 954 Chinese patients was recruited sequentially upon admission in the hospital ward units. They ranged in age from 17 to 100 years, with a mean of 70.2 years. METHODS: The patients were assessed for fall risk using the MFS on admission. Data was collected on the number of patients who fell rather than the number of falls. RESULTS: The scale had a sensitivity of 31% and a specificity of 83% when the cut-off point was determined at 45. The field test demonstrated excellent inter-rater reliability with an ICC value of 0.97 (95%CI 0.94-0.98). Repeatability was high with an ICC of 0.98 (95% CI 0.98-0.99). The evaluation revealed a low Cronbach's alpha coefficient and a low to moderate item-to-scale correlation. CONCLUSIONS: The evidence collected in this study has shown both the positive and negative aspects of using the MFS in assessing the fall risk of Chinese patients during rehabilitation. The discriminative validity and internal consistency reliability provide researchers and clinicians with a major step in further developing or modifying the scale.

Benefits of cardiac resynchronization therapy for heart failure patients with narrow QRS complexes and coexisting systolic asynchrony by echocardiography.

OBJECTIVES: This study was designed to evaluate the role of cardiac resynchronization therapy (CRT) in heart failure (HF) patients with narrow QRS complexes (<120 ms) and echocardiographic evidence of mechanical asynchrony. BACKGROUND: Cardiac resynchronization therapy is currently recommended to advanced HF patients with prolonged QRS duration. Echocardiographic assessment of systolic mechanical asynchrony has been proven useful to predict a favorable response after CRT. METHODS: A total of 102 HF patients with New York Heart Association (NYHA) functional class III or IV were enrolled. Among them, 51 had wide QRS (>120 ms) and 51 had narrow QRS (<120 ms). Tissue Doppler imaging (TDI) was employed to select patients with systolic asynchrony (increased asynchrony index) in the narrow-QRS group. Clinical and echocardiographic assessments were performed at baseline and 3 months after CRT. RESULTS: There was a significant reduction of left ventricular (LV) end-systolic volume in both narrow (122 +/- 42 cc vs. 103 +/- 47 cc, p < 0.001) and wide (148 +/- 74 cc vs. 112 +/- 64 cc, p < 0.001) QRS groups. Improvement of NYHA functional class (both p < 0.001), maximal exercise capacity (both p < 0.05), 6-min hall-walk distance (both p < 0.01), ejection fraction (both p < 0.001), and mitral regurgitation (both p < 0.005) was also observed. In both groups, the degree of baseline mechanical asynchrony determined LV reverse remodeling to a similar extent, as shown by the superimposed regression lines. Withholding CRT for 4 weeks resulted in loss of echocardiographic benefits. CONCLUSIONS: Cardiac resynchronization therapy for HF patients with narrow QRS complexes and coexisting mechanical asynchrony by TDI results in LV reverse remodeling and improvement of clinical status. The amplitude of benefit is similar to the wide-QRS group provided that similar extent of systolic asynchrony is selected.

Pulmonary hypertension, hyperthyroidism, and fenfluramine: a case report and review.

We report a case of pulmonary hypertension presenting with sudden cardiac arrest, hyperthyroidism and fenfluramine usage. This fatal case of pulmonary hypertension and valvular heart disease is associated with the use of an anorectic drug that had been withdrawn from the market more than eight years ago. Clinicians should alert to the side effects of appetite suppressant and slimming agents. The association between pulmonary hypertension in relation to hyperthyroidism and fenfluramine usage is reviewed.

Improvement of serum NT-ProBNP predicts improvement in cardiac function and favorable prognosis after cardiac resynchronization therapy for heart failure.

BACKGROUND: Cardiac resynchronization therapy (CRT) is now an established therapy for patients with advanced heart failure with electromechanical delay, although nonresponders have been observed. Because natriuretic peptides are relevant markers to reflect the severity of heart failure and filling pressure of cardiac chambers, it may be helpful to assess the efficacy of CRT. METHODS AND RESULTS: Forty-two patients with heart failure with QRS of >120 msec were recruited; their serial N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were measured at baseline and at 1 and 3 months after CRT. There was a reduction in NT-proBNP level 1 month after CRT (2655 +/- 2242 pg/mL vs 2149 +/- 2033 pg/mL; P = .03), which was further reduced at 3 months (1473 +/- 1786 pg/mL; P < .001 vs baseline). The reduction of NT-proBNP correlated with the change of left ventricular (LV) end-systolic volume (r = 0.53; P = .001) or LV ejection fraction ( r = -0.49; P = .002) and with improvement in exercise capacity after CRT for 3 months (r = 0.50; P = .002). The patients were classified by the degree of reduction in NT-proBNP as group 1 (reduction of > or =50% vs baseline; n = 19) and group 2 (reduction of <50% vs baseline; n = 23). The degree of LV reverse remodeling (-31.8 +/- 24.7 mL vs -12.6 +/- 19.2 mL; P = .007) and gain in LV ejection fraction (+12.5% +/- 8.8% vs +4.6% +/- 5.8%; P = .002) were significantly better in group 1 than group 2. Both the all-cause mortality rate (Log-rank chi 2 = 4.01; P = .04) and the composite end-point of mortality rate or hospitalization rate for cardiovascular causes (Log-rank chi 2 = 4.31; P = .02) were significantly lower in group 1 than in group 2. CONCLUSION: Serial monitoring of NT-proBNP may be helpful to predict a favorable outcome after CRT. Those who had a reduction of NT-proBNP level of >/=50% were more likely to exhibit a favorable response.

Preparedness of the cardiac catheterization laboratory for severe acute respiratory syndrome (SARS) and other epidemics.

Severe acute respiratory syndrome (SARS) is a highly contagious disease that has led to large hospital and community outbreaks, necessitating stringent infection control in its management. Among 90 SARS patients in our institution in the 2003 outbreak, 2 underwent cardiac catheterization. We report the personal respiratory protection and environmental control measures implemented to minimize the risk of droplets spread during these procedures, including re-engineering of the ventilation system of the cardiac catheterization laboratory (CCL). The report highlights the importance of collaboration of CCL personnel with relevant hospital engineering and management teams to develop a contingency infection control plan to prepare for future outbreaks of SARS or other epidemics.

Comparison of efficacy of reverse remodeling and clinical improvement for relatively narrow and wide QRS complexes after cardiac resynchronization therapy for heart failure.

INTRODUCTION: Cardiac resynchronization therapy (CRT) has been shown to reverse left ventricular (LV) remodeling and improve symptoms in heart failure patients with wide QRS complexes; however, its role in patients with mildly prolonged QRS complexes is unclear. This study investigated if CRT benefited patients with mildly prolonged QRS complexes >120 to 150 ms and explored if the severity of systolic asynchrony determined such a response. METHODS AND RESULTS: Fifty-eight patients (age 66 +/- 11 years, 66% male) who had undergone CRT were studied prospectively. Of these patients, 27 had QRS duration between 120 and 150 ms (group A), and 31 had QRS duration >150 ms (group B). Tissue Doppler echocardiography and clinical assessment were performed at baseline and 3 months after CRT. Both groups had significant reduction of LV volume and increased ejection fraction, +dP/dt, and sphericity index (all P < 0.05). These improvements were greater in group B and were explained by the higher prevalence of systolic intraventricular asynchrony. Significant reverse remodeling (reduction of LV end-systolic volume >15%) was evident in 46% of group A patients and 68% of group B patients. Improvement in clinical endpoints was observed in both groups (all P < 0.01), although the changes in metabolic equivalent and New York Heart Association functional class were greater in group B. In both groups, systolic asynchrony index (TS-SD) was the most important predictor of reverse remodeling (r =-0.78, P < 0.001) and was the only independent predictor in the multivariate model (beta=-1.80, confidence interval =-2.18 to -1.42, P < 0.001); QRS duration was not. A predefined TS-SD value >32.6 ms had a sensitivity of 94% and specificity of 83% to predict reverse remodeling. Improvement of intraventricular asynchrony after CRT was evident only in responders (P = 0.01). CONCLUSION: Improvement of LV remodeling and clinical status is evident after CRT in heart failure patients with QRS duration >120 to 150 ms. These responders are closely predicted by the severity of prepacing intraventricular asynchrony but not QRS duration.

Tissue Doppler imaging is superior to strain rate imaging and postsystolic shortening on the prediction of reverse remodeling in both ischemic and nonischemic heart failure after cardiac resynchronization therapy.

BACKGROUND: A number of noninvasive techniques have been used to predict the effectiveness of cardiac resynchronization therapy (CRT) in heart failure patients, in particular left ventricular (LV) reverse remodeling. This study compared the relative predictive values of tissue Doppler imaging (TDI) and strain-rate imaging (SRI) parameters for LV reverse remodeling in patients who received CRT and examined for potential differences in ischemic (n=22) and nonischemic (n=32) heart failure. METHODS AND RESULTS: TDI and SRI were performed at baseline and 3-month follow-up. Eighteen parameters of intraventricular and interventricular asynchrony based on the time to peak myocardial contraction (Ts) and time to peak strain rate (Tsr) were compared, along with postsystolic shortening (PSS). Reverse remodeling with reduction of LV end-diastolic and end-systolic volumes and gain in ejection fraction (all P<0.001) was observed in the whole study population. The standard deviation of Ts of 12 LV segments (Ts-SD) is the most powerful predictor of reverse remodeling in both the ischemic (r=-0.65, P<0.001) and nonischemic (r=-0.79, P<0.001) groups. The PSS of 12 LV segments was a good predictor only for the nonischemic (r=-0.64, P<0.001) but not the ischemic (r=0.32, P=NS) group. However, parameters of SRI and interventricular asynchrony failed to predict reverse remodeling. By multiple regression analysis, independent parameters included Ts-SD in both groups (P<0.005) and PSS of 12 LV segments in the nonischemic group (P=0.03). The area of the receiver operating characteristic curve was largest for Ts-SD (0.94; CI=0.88 to 1.00). CONCLUSIONS: Ts-SD is the most powerful predictor of LV reverse remodeling and was consistently useful for ischemic and nonischemic heart failure. However, PSS is useful only for nonischemic pathogenesis, whereas the role of SRI parameters was not supported by the present study.