Rapid and Reliable Identification of Staphylococcus aureus Capsular Serotypes by Means of Artificial Neural Network-Assisted Fourier Transform Infrared Spectroscopy

Staphylococcus aureus capsular polysaccharides (CP) are important virulence factors and represent putative targets for vaccine development. Therefore, the purpose of this study was to develop a high-throughput method to identify and discriminate the clinically important S. aureus capsular serotypes 5, 8, and NT (nontypeable). A comprehensive set of clinical isolates derived from different origins and control strains, representative for each serotype, were used to establish a CP typing system based on Fourier transform infrared (FTIR) spectroscopy and chemometric techniques. By combining FTIR spectroscopy with artificial neuronal network (ANN) analysis, a system was successfully established, allowing a rapid identification and discrimination of all three serotypes. The overall accuracy of the ANN-assisted FTIR spectroscopy CP typing system was 96.7% for the internal validation and 98.2% for the external validation. One isolate in the internal validation and one isolate in the external validation failed in the classification procedure, but none of the isolates was incorrectly classified. The present study demonstrates that ANN-assisted FTIR spectroscopy allows a rapid and reliable discrimination of S. aureus capsular serotypes. It is suitable for diagnostic as well as large-scale epidemiologic surveillance of S. aureus capsule expression and provides useful information with respect to chronicity of infection.     

A novel small molecule approach for the treatment of propionic and methylmalonic acidemias

Propionic Acidemia (PA) and Methylmalonic Acidemia (MMA) are inborn errors of metabolism affecting the catabolism of valine, isoleucine, methionine, threonine and odd-chain fatty acids. These are multi-organ disorders caused by the enzymatic deficiency of propionyl-CoA carboxylase (PCC) or methylmalonyl-CoA mutase (MUT), resulting in the accumulation of propionyl-coenzyme A (P-CoA) and methylmalonyl-CoA (M-CoA in MMA only). Primary metabolites of these CoA esters include 2-methylcitric acid (MCA), propionyl-carnitine (C3), and 3-hydroxypropionic acid, which are detectable in both PA and MMA, and methylmalonic acid, which is detectable in MMA patients only (Chapman et al., 2012). We deployed liver cell-based models that utilized PA and MMA patient-derived primary hepatocytes to validate a small molecule therapy for PA and MMA patients. The small molecule, HST5040, resulted in a dose-dependent reduction in the levels of P-CoA, M-CoA (in MMA) and the disease-relevant biomarkers C3, MCA, and methylmalonic acid (in MMA). A putative working model of how HST5040 reduces the P-CoA and its derived metabolites involves the conversion of HST5040 to HST5040-CoA driving the redistribution of free and conjugated CoA pools, resulting in the differential reduction of the aberrantly high P-CoA and M-CoA. The reduction of P-CoA and M-CoA, either by slowing production (due to increased demands on the free CoA (CoASH) pool) or enhancing clearance (to replenish the CoASH pool), results in a net decrease in the CoA-derived metabolites (C3, MCA and MMA (MMA only)). A Phase 2 study in PA and MMA patients will be initiated in the United States.     

Attachment organization in Vietnam combat veterans with posttraumatic stress disorder

Attachment organization in a combat-related PTSD sample was investigated and compared with previously published clinical and non-clinical samples. The association between insecure attachment and unresolved mourning classification (U-loss) and between U-loss and PTSD symptoms was investigated. Vietnam combat veterans diagnosed with PTSD and in treatment (N = 48) were administered the Adult Attachment Interview, the SCID-IV, and CAPS. The PTSD sample was like non-clinical samples in the incidence of secure attachment (50%), but were more commonly unresolved. Veterans with insecure attachment organizations were more likely than those with secure attachment to be classified U-loss. U-loss classification was associated with greater likelihood of comorbid anxiety disorders and PTSD avoidance/numbing symptoms. The results suggest that while insecure attachment organization is associated with unresolved mourning in response to loss, it is not differentially associated with combat-related PTSD. The relationship between U-loss and PTSD is discussed in light of current literature.     

International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire: validation of the asthma component among Brazilian children.

Written questionnaires have been widely used in epidemiological studies of asthma. However, when translated to another language, they must be validated. The International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire had been previously validated by a comprehensive study, but this had not been done in Brazil. Our objective was to validate the asthma component of the ISAAC self-applicable written questionnaire following its translation to Portuguese. A group of 10 pediatricians and 10 pediatric allergists graded the questions from 0 to 2, and established a maximum score for each question. The questionnaire was answered by parents or guardians of asthmatic children, aged 6 to 7 years old (n = 26) and of nonasthmatic control children of the same age (n = 26); and by asthmatic (n = 33) and nonasthmatic (n = 33) adolescents, aged 13 to 14 years. Half of these individuals responded to the same questionnaire after 2 to 4 weeks. This second response allowed the evaluation of the reproducibility of the ISAAC questionnaire. The maximum global score possible was 14, and cut-off levels of 5 and 6 were found for the groups of 6 to 7 and 13 to 14 year olds, respectively. There was significant agreement between the adolescents' responses to the questionnaire and those from their parents or guardians (74.3%); however, significant discordance was observed for individual questions including "wheezing with exercise." In both age periods the questionnaire was significantly reproducible (Kappa test) (6 to 7 year olds Kw = 1; 13 to 14 year olds Kw = 0.89). In conclusion, the asthma component of the ISAAC written questionnaire was proven to be reproducible, adequate and able to differentiate between asthmatics and controls. Adolescents answered the questionnaire appropriately, however the results suggest that adolescents' parents or guardians underestimate asthma symptoms which interfere little with the adolescent's daily activities.     

Methicillin-resistant Staphylococcus aureus in children with cystic fibrosis: An eradication protocol

A retrospective 12-year study (May 1988-July 2000) was undertaken in children with cystic fibrosis (CF) to evaluate 1) the magnitude of methicillin-resistant Staphylococcus aureus (MRSA) in these children; 2) the clinical impact of MRSA on CF; and 3) the efficacy of an MRSA protocol aimed at the eradication of the carrier state. The study maneuver comprised of 1) surveillance cultures of throat/rectum to detect the MRSA carrier state; 2) life-long cephradine rather than flucloxacillin to lift selection pressure; 3) topical application of oral and nebulized vancomycin for 5 days to clear the carriage of MRSA; and 4) a strict antistaphylococcal hygiene program, including handwashing and device policy. Fifteen children with CF (11 boys, with median age 117 months) positive for MRSA were enrolled. The current prevalence of MRSA among children with CF in our hospital is 6.5%. Of 15 children identified, only 12 (18 episodes of MRSA colonization) were treated according to protocol. Median age of MRSA acquisition was 73 months (interquartile range, 43-134 months). In 7 patients (55%), MRSA was eradicated. Of a total of 18 MRSA episodes, the protocol was successful in 10 episodes. The mean period of MRSA-free status was 12 months (range, 6-36 months). Pulmonary function (measured by FEV(1)) was not affected (68% of predicted before treatment, and 68% of predicted after treatment). All children were oropharyngeal carriers of both MRSA and ceftazidime-resistant P. aeruginosa. We believe that an effort has to be made to limit MRSA in CF clinics for the following reasons: 1) MRSA carriage in any individual is an abnormal condition; 2) limitation of systemic vancomycin use is desirable; 3) MRSA carriage may be a contraindication for lung transplantation; and 4) epidemiologically, a CF unit with a substantial MRSA problem functions as a source of dissemination for other patients.     

Marcadores de daño miocárdico en la predicción del pronóstico a corto plazo de los pacientes con COVID-19

Introduction and objectivesCOVID-19 is currently causing high mortality and morbidity worldwide. Information on cardiac injury is scarce. We aimed to evaluate cardiovascular damage in patients with COVID-19 and determine the correlation of high-sensitivity cardiac-specific troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) with the severity of COVID-19.MethodsWe included 872 consecutive patients with confirmed COVID-19 from February to April 2020. We tested 651 patients for high-sensitivity troponin T (hs-TnT) and 506 for NT-proBNP on admission. Cardiac injury was defined as hs-TnT > 14 ng/L, the upper 99th percentile. Levels of NT-proBNP > 300 pg/mL were considered related to some extent of cardiac injury. The primary composite endpoint was 30-day mortality or mechanical ventilation (MV).ResultsCardiac injury by hs-TnT was observed in 34.6% of our COVID-19 patients. Mortality or MV were higher in cardiac injury than noncardiac injury patients (39.1% vs 9.1%). Hs-TnT and NT-proBNP levels were independent predictors of death or MV (HR, 2.18; 95%CI, 1.23-3.83 and 1.87 (95%CI, 1.05-3.36), respectively) and of mortality alone (HR, 2.91; 95%CI, 1.211-7.04 and 5.47; 95%CI, 2.10-14.26, respectively). NT-ProBNP significantly improved the troponin model discrimination of mortality or MV (C-index 0.83 to 0.84), and of mortality alone (C-index 0.85 to 0.87).ConclusionsMyocardial injury measured at admission was a common finding in patients with COVID-19. It reliably predicted the occurrence of mortality and need of MV, the most severe complications of the disease. NT-proBNP improved the prognostic accuracy of hs-TnT.     

Inhibition of Aurora kinases enhances chemosensitivity to temozolomide and causes radiosensitization in glioblastoma cells

Background  

Glioblastoma remains one of the most devastating human malignancies, and despite therapeutic advances, there are no drugs that significantly improve the patient survival. Altered expression of the Aurora kinases was found in different malignancies, and their inhibition has been studied in cancer therapy. In this study, we analyzed the expression of Aurora A and Aurora B in glioblastoma samples and also analyzed whether the effects of Aurora kinase inhibition were associated with temozolomide or not on cell lines and primary cultures of glioblastoma.