Optimal sampling time after preparation of platelet concentrates for detection of bacterial contamination by quantitative real-time polymerase chain reaction

BACKGROUND AND OBJECTIVES: A universal quantitative real-time polymerase chain reaction (PCR), based on bacterial 16S rDNA, to detect bacterial contamination of platelet concentrates (PCs), was developed previously and compared with automated culturing. In the present study, this real-time PCR method was evaluated to determine the optimal sampling time for screening of bacterial contamination in PCs. MATERIALS AND METHODS: Routinely prepared PCs were spiked with suspensions of Escherichia coli, Bacillus cereus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Propionibacterium acnes to 1, 10 and 100 colony-forming units (CFU)/ml and stored at room temperature for 7 days. The presence of bacteria in these PCs was monitored by quantitative real-time PCR. As a reference method (additional control), BacT/Alert automated culturing was used. For PCR, 1-ml aliquots were drawn from all (spiked) PCs on days 0, 1, 2, 3, 6 and 7 of storage. As a control, triplicate samples (10 ml) were inoculated into aerobic and anaerobic BacT/Alert culture bottles immediately after spiking (day 0) and after storage for 1, 2, 3, 6 or 7 days. RESULTS: With quantitative real-time PCR, all bacterial species tested were reproducibly detected on day 1 after spiking at original concentrations of 10 and 100 CFU/ml. Bacteria were also detected on day 1 from PCs spiked with an initial concentration of 1 CFU/ml, except for E. coli, which was detected in only one of the three samples and P. aeruginosa, for which analysis was not performed on day 1. With the reference method, bacteria were detected in culture bottles (inoculated on day 0) within a mean time of 20.1 h, with the exception of P. acnes which was detected at a mean time of 102.3 and 49.3 h (for original spiking concentrations of 10 and 100 CFU/ml respectively). CONCLUSIONS: PCR enables the rapid detection of low initial numbers of bacteria in PCs. For reliable detection, our results support that sampling of PCs for real-time PCR screening should not be carried out earlier than 1 day after preparation (48 h after blood collection). Importantly, the real-time PCR approach has the potential to be used before the release of PCs from the blood centre or shortly before they are transfused in the hospital.     

2,6 di-tert-butylphenol, a nonanesthetic propofol analog, modulates alpha1beta glycine receptor function in a manner distinct from propofol

The anesthetic propofol (2,6 diisopropylphenol) mediates some of its effects by activating inhibitory chloride currents in the lower brainstem and spinal cord. The effects comprise direct activation of gamma-aminobutyric acid-A and glycine receptors in the absence of the natural agonist, as well as potentiation of the effect of submaximal agonist concentrations. Replacement of propofol's isopropyl groups by di-tert-butyl groups yields a compound without in vivo anesthetic effects. We have studied the effects of propofol and 2,6 di-tert-butylphenol on chloride inward currents via rat alpha1beta glycine receptors heterologously expressed in human embryonic kidney cells. Propofol, but not 2,6 di-tert-butylphenol, directly activated glycine receptors; half-maximal current activation was observed with propofol 114 +/- 27 microM. Both compounds potentiated the effect of a submaximal glycine concentration (10 microM) to a maximum value of 136% +/- 71% (propofol) and 279% +/- 109% (2,6 di-tert-butylphenol) of the response to glycine 10 microM. The 50% effective concentration for this effect was 12.5 +/- 6.4 microM and 9.4 +/- 10.2 microM for propofol and 2,6 di-tert-butylphenol, respectively. Propofol and its nonanesthetic structural analog do not differ in their ability to coactivate the glycine receptor but differ in their ability to directly activate the receptor in the absence of the natural agonist.     

Is surgical intervention still indicated in recurrent aortic arch obstruction?

BACKGROUND: Introduction of balloon dilatation has become the standard treatment for recurrent aortic arch obstruction and has changed the therapeutic approach to patients with this disorder. OBJECTIVES: Whether all patients with recurrent aortic arch obstruction are candidates for balloon dilatation remains unanswered. In addition, only few reports have tried to compare the results between patients undergoing balloon dilatation or redo operations. METHODS: Since 1983, 97 patients underwent reintervention for recurrent aortic arch obstruction (42 dilations and 55 reoperations). Eight had immediate unsuccessful dilatation and were shifted to the surgical group (n = 63). The median age at reintervention was 21.7 months (10 days-45 years), and the median delay was 13.6 months (7 days-17 years). Anatomy of the aortic arch oriented the surgical approach to treat arch hypoplasia. It could be performed through a left thoracotomy in 52 patients, with extended end-to-end anastomosis in 34 patients, subclavian flap repair in 9 patients, conduit insertion in 6 patients, and patch enlargement in 3 patients. More recently, an anterior approach with cardiopulmonary bypass without circulatory arrest was applied to enlarge the patch in all the aortic arches. RESULTS: There was one early death in the surgical intervention group and 2 late deaths in the dilation group. Major complications and recurrence were higher in the dilated group (4 vs 0, P <.01, and 14 vs 5, P <.0004, respectively). At a mean follow-up of 11.8 +/- 4.1 years in the surgical intervention group and 7.5 +/- 2.5 years in the dilated group, systemic hypertension was normalized in all but 5 patients in the surgical intervention group and 6 patients in the dilated group. CONCLUSION: Reoperation for recurrent aortic arch obstruction can be performed safely, with low rates of mortality and morbidity. This approach should be considered versus balloon angioplasty, especially in patients older than 4 years and in the presence of aortic arch hypoplasia.     

Zinc sulfate as an adjunct to methylphenidate for the treatment of attention deficit hyperactivity disorder in children: A double blind and randomized trial [ISRCTN64132371]

Background  

Attention-deficit hyperactivity disorder is an early-onset, clinically heterogenous disorder of inattention, hyperactivity, and impulsiveness. The diagnosis and treatment of attention-deficit hyperactivity disorder continues to raise controversy, and, there is also an increase in treatment options. In this 6-week double blind, placebo controlled-trial, we assessed the effects of zinc plus methylphenidate in the treatment of children with attention deficit hyperactivity disorder. To the best of our knowledge, this study is the first double blind and placebo controlled clinical trial assessing the adjunctive role of zinc in ADHD.     

Positive inotropic effect of ouabain on isolated heart is accompanied by activation of signal pathways that link Na+/K+-ATPase to ERK1/2

Exposure of cultured rat cardiac myocytes to ouabain is known to cause the interaction of Na+/K+-ATPase with adjacent proteins, leading to activation of multiple signal transduction pathways, regulation of growth-related genes, and hypertrophy. The aim of this work was to determine if the proximal signaling events identified in cultured myocytes also occur in isolated intact hearts of rat and guinea pig in response to positive inotropic doses of ouabain. Langendorff rat heart preparations were exposed to 50 microM ouabain to produce positive inotropy without toxicity, and assayed for Src kinase, protein kinase C, and extracellular signal-regulated kinases 1 and 2 (ERK(1/2)). These kinases were rapidly activated by ouabain as in cultured cells. In isolated guinea pig hearts, 1 microM ouabain caused ERK(1/2) activation comparable to the effect of 50 microM ouabain in rat heart and consistent with the higher ouabain sensitivity of the contractility of guinea pig heart. These data show that the proximal ouabain-induced signal pathways previously noted in cultured cells are not artifacts of dispersion/culturing of myocytes, and are not the peculiar properties of the rat heart with its relatively low ouabain sensitivity. They also suggest that treatment with positive inotropic doses of cardiac glycosides is likely to be associated with changes in the cardiac phenotype.     

Interaction of the neuroprotective drug riluzole with GABA(A) and glycine receptor channels

Riluzole is used as therapeutic agent in amyotrophic lateral sclerosis. We investigated the interaction of riluzole with recombinant GABA (gamma-aminobutyric acid)(A) receptor channels (alpha(1)beta(2)gamma(2)-subunits) and glycine receptor channels (alpha(1)beta-subunits) transiently expressed in HEK293 cells. For electrophysiological experiments, the patch-clamp technique in combination with tools for ultrafast solution exchange was used. Saturating concentrations of GABA or glycine were applied with different concentrations of riluzole to outside-out patches containing alpha(1)beta(2)gamma(2) GABA(A) receptor channels or alpha(1)beta-glycine receptor channels on their surface, respectively. The current declined after application of GABA or glycine with three time constants of desensitization to a steady-state current amplitude. Application of riluzole resulted in a shift to fast desensitized states at both receptors. The proportion of the time constants of fast desensitization increased and the time constants of slow desensitization and the steady-state current decreased whereas the maximal current amplitudes were not affected by riluzole. The data of the study demonstrate for the first time interaction of GABAergic and glycinergic currents with riluzole under physiological conditions.     

Dietary factors and body mass index in a group of Iranian adolescents: Tehran lipid and glucose study--2

OBJECTIVE: To study the prevalence of overweight and obesity in an adolescent population in Tehran and to determine possible association with energy and nutrient intake and distribution of energy over the day. METHOD: A cross-sectional study on 177 boys and 244 girls between 10-19 years old was performed. Overweight and obesity were defined by using recommended body mass index (BMI) cut-off values for adolescents. Total energy intake, percent of energy derived from protein, carbohydrate and fat and percent of energy supplied by each meal and snack were assessed by means of two 24-hour dietary recalls. RESULTS: Prevalence of overweight and obesity was 10.7 and 5.1 in boys and 18.4 and 2.8 in girls, respectively. The composition of diet was not different between overweight/obese and normal weight subjects. BMI was related with breakfast energy percentage in girls (r = -0.18, p < 0.01), with total energy intake in boys (r = 0.23, p < 0.01), and with lunch energy percentage in both sexes. In boys (r = 0.16, p < 0.05) and in girls (r = 0.22, p < 0.01). CONCLUSION: High prevalence of overweight and obesity among adolescents was seen. In boys some relationship between total energy intake, distribution of energy over the day and BMI was seen. In girls BMI was only related with distribution of energy over the day.     

Conceptualizing a Quality Plan for Healthcare

Today, health systems around the world are under pressure to create greater value for patients and society; increasing access, improving client orientation and responsiveness, reducing medical errors and safety, restraining utilization via managed care, and implementing priority allocation of resources for high-burden health problems are examples of strategies towards this end. The quality paradigm by virtue of its strategic consumer focus and its methods for achieving operational excellence has proved an effective approach for creating higher value in many sectors. If applied in a deliberate and holistic manner, the quality paradigm can bring about a more cost-effective organization of the health systems. In this article, we apply quality concepts to healthcare in a conceptual format; we characterize the health system's customers and outputs with their quality dimensions. The product of this effort is a blueprint for a customer-driven health system which identifies six types of customers, nine types of outputs and the associated operations. As a preliminary step, a new analysis and definition of health and disease is provided. Rethinking the structure of health system in this manner and the related conceptual model can guide medical research, health sciences education, and health services policy, and help the practitioner to integrate all modern trends in healthcare delivery.     

Association of Vitamin D Status with SARS-CoV-2 Infection or COVID-19 Severity: A Systematic Review and Meta-analysis

This systematic review was conducted to summarize and clarify the evidence on the association between 25-hydroxyvitamin-D [25(OH)D] concentrations and coronavirus disease 2019 (COVID-19) risk and outcomes. PubMed, Scopus, and Web of Science databases and Google Scholar were searched up to 26 November 2020. All retrospective and prospective cohort, cross-sectional, case-control, and randomized controlled trial studies that investigated the relation between 25(OH)D and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19 severity were included. Thirty-nine studies were included in the current systematic review. In studies that were adjusted (OR: 1.77; 95% CI: 1.24, 2.53; I²: 44.2%) and nonadjusted for confounders (OR: 1.75; 95% CI: 1.44, 2.13; I²: 33.0%) there was a higher risk of SARS-CoV-2 infection in the vitamin D deficiency (VDD) group. Fifteen studies evaluated associations between VDD and composite severity. In the studies that were adjusted (OR: 2.57; 95% CI: 1.65, 4.01; I² = 0.0%) and nonadjusted for confounders (OR: 10.61; 95% CI: 2.07, 54.23; I² = 90.8%) there was a higher severity in the VDD group. Analysis of studies with crude OR (OR: 2.62; 95% CI: 1.13, 6.05; I²: 47.9%), and adjusted studies that used the Cox survival method (HR: 7.67; 95% CI: 3.92, 15.03; I²: 0.0%) indicated a significant association of VDD with mortality, while in adjusted studies that used logistic regression, no relation was observed (OR: 1.05; 95% CI: 0.63, 1.75; I²: 76.6%). The results of studies that examined relations between VDD and intensive care unit (ICU) admission, pulmonary complications, hospitalization, and inflammation were inconsistent. In conclusion, although studies were heterogeneous in methodological and statistical approach, most of them indicated a significant relation between 25(OH)D and SARS-CoV-2 infection, COVID-19 composite severity, and mortality. With regard to infection, caution should be taken in interpreting the results, due to inherent study limitations. For ICU admission, inflammation, hospitalization, and pulmonary involvement, the evidence is currently inconsistent and insufficient.