Universal Digital High-Resolution Melt Analysis for the Diagnosis of Bacteremia

Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires approximately 15 hours to detect the presence of a pathogen. We, therefore, assessed the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 17 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 88% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1-mL sample input and sample-to-answer time of 6 hours. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection.

Macrophage Polarizations in the Placenta and Lung are Associated with Bronchopulmonary Dysplasia

The intricate interplay between macrophage polarization and placenta vascular dysfunction has garnered increasing attention in the context of placental inflammatory diseases. This study delves into the complex relationship between macrophage polarization within the placenta and its potential impact on the development of vascular dysfunction and inflammatory conditions. The placenta, a crucial organ in fetal development, relies on a finely tuned balance of immune responses for proper functioning. Disruptions in this delicate equilibrium can lead to pathological conditions, including inflammatory diseases affecting the fetus and newborn infant. We explored the interconnectedness between placental macrophage polarization and its relevance to lung macrophages, particularly in the context of early life lung development. Bronchopulmonary dysplasia (BPD), the most common chronic lung disease of prematurity, has been associated with abnormal immune responses, and understanding the role of macrophages in this context is pivotal. The investigation aims to shed light on how alterations in placental macrophage polarization may contribute to lung macrophage behavior and, consequently, influence the development of BPD. By unraveling the intricate mechanisms linking macrophage polarization, placental dysfunction and BPD, this research seeks to provide insights that could pave the way for targeted therapeutic interventions. The findings may offer novel perspectives on preventing and managing placental and lung-related pathologies, ultimately contributing to improved maternal and neonatal health outcomes.

Contribution of Concurrent Comorbidities to Sepsis-Related Mortality in Preterm Infants ≤32 Weeks of Gestation at an Academic Neonatal Intensive Care Network

OBJECTIVE

 This study sought to identify concurrent major comorbidities in preterm infants ≤32 weeks of gestation that may have contributed to sepsis-related mortality following a diagnosis of bacteremia or blood culture-negative sepsis within the neonatal period (≤28 days of life).

STUDY DESIGN

 This is a retrospective chart review of infants ≤32 weeks of gestation who were admitted to a single academic network of multiple neonatal intensive care units between January 1, 2012, and December 31, 2015, to determine the primary cause(s) and timing of death in those diagnosed with bacteremia or blood culture-negative sepsis. Direct comparisons between early-onset sepsis (EOS; ≤72 hours) and late-onset sepsis (LOS; >72 hours) were made.

RESULTS

 In our study cohort, of 939 total patients with ≤32 weeks of gestation, 182 infants were diagnosed with 198 episodes of sepsis and 7.7% (14/182) died. Mortality rates did not significantly differ between neonates with bacteremia or blood culture-negative sepsis (7/14 each group), and those diagnosed with EOS compared with LOS (6/14 vs. 8/14). Nearly 80% (11/14) of infants were transitioned to comfort care prior to their death secondary to a coinciding diagnosis of severe grade-3 or -4 intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, and/or intestinal perforation.

CONCLUSION

 Preexisting comorbidities commonly associated with extreme preterm birth contributed to sepsis-related mortality in our patient cohort.

KEY POINTS

· Concurrent comorbidities contribute to, and may artificially inflate, sepsis-related mortality.. · Absence of a consensus definition for neonatal sepsis complicates the investigation of infection.. · Accurate assessment of the incidence of sepsis in very low birth weight infants is vital for future investigations..

Universal digital high resolution melt analysis for the diagnosis of bacteremia

Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires ∼15 hours to detect the presence of a pathogen. Here, we assess the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 21 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 90.5% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1 mL sample input and sample-to-answer time of 6 hrs. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection.

Universal digital high resolution melt analysis for the diagnosis of bacteremia

April Aralar, Tyler Goshia, Nanda Ramchandar, Shelley M. Lawrence, Aparajita Karmakar, Ankit Sharma, Mridu Sinha, David Pride, Peiting Kuo, Khrissa Lecrone, Megan Chiu, Karen Mestan, Eniko Sajti, Michelle Vanderpool, Sarah Lazar, Melanie Crabtree, Yordanos Tesfai, Stephanie I. Fraley.

TREATMENTS OF HEPATITIS C VIRUS LIVER CIRRHOSIS WITH PEGYLAT INTERFERON-RIBAVIRIN AND INTERFERON FREE – COMPARATIVE STUDY

The article describes the adverse effects and efficiency of hepatitis C virus liver cirrhosis treatments available through the National Health Insurance Services, on a population of patients hospitalized at Victor Babes Infectious and Tropical Diseases Hospital, from 2012 to 2016. The population of patients was split into two distinct groups, for which we’ve recorded and comparatively analyzed demographic, clinical and paraclinical characteristics in a database. An evident success was recorded, from the point of view of hitting a clinical SVR index, in the DAA therapy group A, 87% percent compared to 2% in group B for the traditional standard therapy of PegInterferon + Ribavirin. Likewise, the number of adverse effects was lower in Group B versus Group A. Some side effects remained specific to the current cirrhosis treatment, which should be closely monitored.

P01-341-Socialization aspects in children with stuttering

Stuttering, as a communication disorder, is a field of great interest, with many hypothesis regarding its nature and appropriate treatment. Many studies tried to emphasize the bond between stuttering and anxiety. Frequently, stuttering is associated with strong emotional reaction, as anxiety, emphasized by negative consequences of “not being able to talk accurately”. This turns in avoidance of speak and social problems as school difficulties.

The aim of this study is anxiety evaluation in children with stuttering through specialized psychological intervention.

We applied MASC (Multidimensional Anxiety Scale for Children) and CDI (Child Depression Inventory) to 20 children diagnosed with stuttering, aged 6–16, from Cluj -Napoca, both at the beginning and at the end of the study. Psychological intervention consisted of two evaluation sessions (one with the parent and one with the child) and ten group sessions (psychodrama and cognitive-behavioral techniques).

The results showed a significant decrease of anxiety (p < 0.05), and no difference in depression symptoms (for statistical data we used SPSS 16.0 Program).

Detection of single atoms and buried defects in three dimensions by aberration-corrected electron microscope with 0.5-A information limit

The ability of electron microscopes to analyze all the atoms in individual nanostructures is limited by lens aberrations. However, recent advances in aberration-correcting electron optics have led to greatly enhanced instrument performance and new techniques of electron microscopy. The development of an ultrastable electron microscope with aberration-correcting optics and a monochromated high-brightness source has significantly improved instrument resolution and contrast. In the present work, we report information transfer beyond 50 pm and show images of single gold atoms with a signal-to-noise ratio as large as 10. The instrument's new capabilities were exploited to detect a buried Sigma3 {112} grain boundary and observe the dynamic arrangements of single atoms and atom pairs with sub-angstrom resolution. These results mark an important step toward meeting the challenge of determining the three-dimensional atomic-scale structure of nanomaterials.

Enhancement of resolution in core-loss and low-loss spectroscopy in a monochromated microscope

The significant enhancement of the energy resolution in the new generation of commercially available monochromated transmission electron microscopes presents new challenges in term of selecting the correct experimental conditions and understanding the various effects that can potentially influence the quality of the EELS data. In this respect we investigated the effect of point spread function of the detector and spectrum-diffraction mixing on the energy resolution and the intensity of the zero loss peak tails. Alternative approaches to improve the energy resolution by mathematical methods have been tested. By using a simple and commonly available test case (Si L(2,3) edges) we assessed the efficiency of the deconvolution algorithms to improve the resolution. The results show that the deconvolution is not always successful in improving the resolution of the core loss EELS data and the results may not always be reliable. Contrary to this, the application of the Richardson-Lucy deconvolution algorithm on some bandgap measurements data appears to be very effective. The procedure proved successful in removing the contribution of the zero-loss peak tails and allows an easier access to spectroscopic information starting at energy losses as low as of 0.5 eV with monochromated spectra and 1 eV with the non-monochromated spectra.

Angular and Local Spectroscopic Analysis to Probe the Vertical Alignment of N-doped Well-separated Carbon Nanotubes

Vertically aligned well-separated N-doped multiwalled carbon nanotubes (CNTs) were grown on a silicon substrate by plasma enhanced chemical vapor deposition (PECVD). Angular near-edge X-ray absorption fine structure (NEXAFS) was used to investigate the vertical alignment of as-grown CNTs. In addition, both individual tubes and tube bundles were characterized by high-resolution electron energy loss spectroscopy (HREELS). Simultaneous analysis of both spectroscopic techniques provides information on chemical environment, orbital orientation between carbon and heteroatoms, and local curvature effects. We demonstrate the utility of NEXAFS as an in situ probe of CNTs.

Čerenkov losses: A limit for bandgap determination and Kramers–Kronig analysis

Measuring low energy losses in semiconductors and insulators with high spatial resolution becomes attractive with the increasing availability of modern transmission electron microscopes (TEMs) equipped with monochromators, C(s) correctors and energy filters. In this paper, we demonstrate that Cerenkov losses pose a limit for the interpretation of low energy loss spectra (EELS) in terms of interband transistions and bandgap determination for many materials. If the velocity of a charged particle in a medium exceeds the velocity of light, photons are emitted leading to a corresponding energy loss of a few electronvolt. Since these losses are strong for energies below the onset of interband transitions, they change the apparent loss function of semiconductors and insulators, with the risk of erroneous interpretation of spectra. We measured low energy losses of Si and GaAs with a monochromated TEM demonstrating the effect of sample thickness on Cerenkov losses. Angle resolved EELS and energy filtered diffraction patterns (taken without a monochromator) show the extremely narrow angular distribution of Cerenkov losses. The latter experiment provides a method that allows to decide whether Cerenkov radiation masks the very low loss signal in EELS.

Enantioselective synthesis of 2- and 3-substituted 2,3-dihydro[1,4]dioxino[2,3-b]pyridine derivatives and enantiomeric purity control by capillary electrophoresis

A rapid and simple procedure for enantioselective preparation of 2- and 3-substituted 2,3-dihydro[1,4]dioxino[2,3-b]pyridine derivatives (A and B, respectively) is described. The enantiomeric purity of each isomer was determined by capillary electrophoresis using a dual-cyclodextrin system (S-beta-CD/beta-CD) dissolved in formic acid-ammonia buffer (pH 4, ionic strength 50 mM).

Investigation of hexagonal and cubic GaN by high-resolution electron energy-loss spectroscopy and density functional theory

High-resolution electron energy-loss spectroscopy in a transmission electron microscope is a very powerful method for the study of electronic structure of materials. The fine structure of Ga L(2,3) and N ionization edges in c-GaN and h-GaN was studied using a TEM equipped with a monochromator and high-resolution energy spectrometer. The experimental results were compared with the results of calculation based on the density functional theory using the Wien2k code and show that the best fit is achieved when the core hole effect is taken into account. The effect of the core hole value and the supercell size on the energy-loss near-edge structure have been investigated. A different behaviour was found for c-GaN and h-GaN: better agreement is obtained for a 0.5 core hole for h-GaN and for a full core hole for c-GaN. The anisotropic behaviour of the experimental spectra and calculated spectra for h-GaN have been studied and the "magic" angle was determined.

Materials science applications of HREELS in near edge structure analysis and low-energy loss spectroscopy

New experiments made possible with a commercial transmission electron microscope (TEM) equipped with a high-resolution electron energy loss spectrometer (EELS) are presented. With this commercial system, a 100 meV energy resolution using a sub 2 nm probe or 500 meV at a 0.20 nm probe are possible, in combination with other modern techniques available for TEMs. In this paper a number of explorative examples of the first results are shown. The benefit of the increased resolution for detecting more details in near edge structures are shown for the Ti K edge in TiO(2) (brookite) and for the N K edge in cubic and hexagonal GaN. The bandgap of GaN is studied in both crystal structures, as well as the dependency of the low-loss spectrum on the momentum transfer direction in diffraction mode.

Atypical antipsychotic use in treating adolescents and young adults with developmental disabilities

OBJECTIVE

To study the usage, efficacy, and side effects patterns of atypical neuroleptics (atypicals) in adolescents and young adults with developmental disabilities (DDs) (mental retardation).

METHOD

We undertook a chart review of adolescents and young adults (under age 25 years) seen by our specialized mental health team.

RESULTS

Risperidone and olanzapine were by far the most frequently prescribed atypicals. Robust clinical effects were noted for both psychotic and nonpsychotic disorders. Most patients tolerated atypicals well, although a significant minority did experience neuroleptic induced movement disorders (NIMDs), particularly dystonias and dyskinesias. Female patients with DDs appear to be at particular risk of NIMDs.

CONCLUSIONS

Atypicals are useful in treating various conditions associated with DDs. This population, however, seems particularly sensitive to NIMDs, hence caution and close monitoring are required.

Role of meiosis-activating sterols in rat oocyte maturation: effects of specific inhibitors and changes in the expression of lanosterol 14alpha-demethylase during the preovulatory period

In vitro studies on mouse oocytes have shown that two closely related sterols, subsequently named meiosis-activating sterols (MAS), can overcome the inhibitory effect of hypoxanthine on the resumption of meiosis. These sterols are synthesized by cytochrome P(450) lanosterol 14alpha-demethylase (LDM), a key enzyme in cholesterol biosynthesis. We have used specific inhibitors of LDM, azalanstat (RS-21607) and RS-21745, to test whether MAS is an obligatory mediator in the resumption of meiosis in the rat. Addition of azalanstat and RS-21745 (1-200 microM) to culture medium of rat isolated cumulus-enclosed oocyte and preovulatory follicle-enclosed oocyte stimulated by LH/hCG did not allow separation between their inhibition of the resumption of meiosis and the degeneration of oocytes. In both models, doses of the drug that inhibited oocyte maturation also increased oocyte degeneration. The inhibitors only partially suppressed follicular progesterone production. We have examined by reverse transcriptase-polymerase chain reaction, Western blotting, and immunocytochemistry the ovarian expression of LDM mRNA and protein during the preovulatory period. We did not find evidence for the stimulation of this enzyme by LH/hCG. The strongest staining by LDM antiserum was obtained in primordial and primary oocytes, and the staining was reduced with oocyte growth. In addition, strong LDM staining could be observed in some of the granulosa cells, especially of the corona radiata localized in close proximity to the oocyte. In conclusion, our results with specific inhibitors and molecular approaches do not reveal evidence to support the hypothesis that MAS is an obligatory step in the stimulation of the resumption of meiosis. Specific inhibitors of MAS synthesis did not prevent spontaneous or LH-stimulated meiosis at doses that have previously been shown to effectively suppress LDM activity. Much higher concentrations of the inhibitors, which affected meiosis, were detrimental to oocytes, leading to their degeneration. The timing of LDM expression in the ovary was incompatible with a role for MAS in meiosis. Finally, the preferential localization of LDM protein to the oocytes suggests MAS production in oocytes rather than its transport from the somatic compartment as implied by the proposed role of MAS as a cumulus-oocyte signal molecule.

Synthesis of 2-substituted-2,3- dihydro-1,4-dioxino[2,3-b]pyridine derivatives

[reaction--see text] A variety of 2-substituted-2,3-dihydro-1,4-dioxino[2,3-b]pyridines B have been synthesized from the readily available 2-nitro-3-oxiranylmethoxypyridine 1 via a Smiles rearrangement. We demonstrate how variations of reaction conditions affect the product distribution of A and B.

ToxR-independent expression of cholera toxin from the replicative form of CTXphi

The ctxAB operon, which encodes cholera toxin, resides in the genome of CTXphi, a filamentous bacteriophage. Within Vibrio cholerae cells, the CTXphi genome can exist either as a replicating plasmid or as a prophage integrated into the chromosome. Previous work established that ToxR is required for chromosomal ctxAB expression. We have learned that strains harboring the CTXphi replicative form produce cholera toxin under all conditions tested, independently of ToxR. During passage of CTXphi lysogens through the infant mouse intestine, transduction of CTXphi to a recipient strain can be detected, indicating that phage excision and replication occur in vivo. These results suggest that phage induction might provide a novel mechanism for the regulation of cholera toxin production.

Cytogenetic analysis of intestinal polyps in polyposis syndromes: comparison with sporadic colorectal adenomas

Few cytogenetic studies of polyps from patients with polyposis syndromes have been reported. We studied 27 colonic adenomatous polyps from familial adenomatous polyposis (FAP), two polyps of the small bowel from Peutz-Jeghers syndrome (PJS), and four colorectal juvenile polyps from juvenile polyposis syndrome (JPS). The karyotypic results were compared with 32 sporadic colorectal adenomatous polyps. Nineteen colorectal adenomas had abnormal karyotypes; of these, five were from patients with FAP and 14 were sporadic adenomas. Numerical changes were the most frequent change (14 adenomas); additional copies of chromosome 7 (eight adenomas) and 13 (seven adenomas) occurred most often and were present in both FAP and sporadic adenomas. Only five adenomas, all sporadic, had structural chromosome abnormalities. Normal karyotypes were obtained from 32 adenomas, and chromosome counts but not karyotypes were obtained from eight polyps owing to poor chromosome morphology. The JPS and PJS polyps had normal karyotypes. These data indicate that adenomas from patients with FAP tend to have fewer structural abnormalities than sporadic adenomas and that numerical abnormalities are the most common chromosome abnormality in both FAP and sporadic polyps and suggest that the mechanism which causes loss of heterozygosity (LOH) in the adenoma to carcinoma sequence operates on a level below that of the whole chromosome.

Origin of all three coronary arteries from separate ostia in the right sinus of Valsalva: a rarely reported coronary artery anomaly

Anomalous origin of the circumflex and left anterior descending coronary arteries from separate ostia in the right sinus of Valsalva is a rarely reported phenomenon. Few clinical details concerning patients with this anomaly are available in the literature. Angiographic and clinical data in an adult patient with this finding are reported here.

Erythrocytes as carriers of new anti-opioid prodrugs: in vitro studies

In using a reversed hypoosmotic lysis and resealing process, internalization of Naloxone or Naltrexone prodrugs as new opioid antagonists into red blood cells (RBC) can be obtained. We describe the entrapment method and haematological parameters of such RBC carriers. Percentages of internalization range between 35% and 70%, depending on the prodrug. The stability of the different prodrugs within RBC, after in vitro internalization have been compared at 4 degrees C and 37 degrees C. These studies were performed in order to screen and choose the most interesting prodrugs for in vivo studies. Some prodrugs tested appeared to be stable after 24 hours of incubation, but others were not. The intracellular ATP and 2,3 BPG concentrations of RBC carriers were similar to the control.

Jaw dislocation during general anaesthesia

A case is reported of jaw dislocation on placement of an oral airway and nasogastric tube during an otherwise unremarkable exploratory laparotomy under general anaesthesia. The pathophysiology, diagnosis and treatment of jaw dislocation are described.

Reactivity of lymphocytes from primary neoplasms of lymphoid tissues

Proliferative responses by blood and tumor lymphocytes to plant mitogens and allogeneic leukocyte antigens were tested concomitantly on 12 patients with Hodgkin's disease, 10 with chronic lymphocytic leukemia, and seven with non-Hodgkin's lymphomas. In 13 control studies, 3H-thymidine incorporation by blood and lymph node lymphocytes was brisk and, overall, comparable. With Hodgkin's disease, where extent of disease involvement and lymphocyte-depleted tumor histology were factors in the degree of responsiveness, incorporation was higher or at least comparable by tumor lymphocytes when compared with incorporation by autologous blood lymphocytes. Lymph node lymphocytes, especially with clinically stable disease, were more responsive than blood lymphocytes with chronic lymphocytic leukemia. Conversely, tumor lymphocytes were hyporesponsive compared with autologous blood lymphocytes with non-Hodgkin's lymphomas, where prognosis is usually less favorable than with chronic lymphocytic leukemia. Plasma from four out of 33 patients, although not lymphocytotoxic, inhibited lymphoproliferative responses.