Identifying the suite of genes central to swimming in the biocontrol bacterium Pseudomonas protegens Pf-5

Swimming motility is a key bacterial trait, important to success in many niches. Biocontrol bacteria, such as Pseudomonas protegens Pf-5, are increasingly used in agriculture to control crop diseases, where motility is important for colonization of the plant rhizosphere. Swimming motility typically involves a suite of flagella and chemotaxis genes, but the specific gene set employed for both regulation and biogenesis can differ substantially between organisms. Here we used transposon-directed insertion site sequencing (TraDIS), a genome-wide approach, to identify 249 genes involved in P. protegens Pf-5 swimming motility. In addition to the expected flagella and chemotaxis, we also identified a suite of additional genes important for swimming, including genes related to peptidoglycan turnover, O-antigen biosynthesis, cell division, signal transduction, c-di-GMP turnover and phosphate transport, and 27 conserved hypothetical proteins. Gene knockout mutants and TraDIS data suggest that defects in the Pst phosphate transport system lead to enhanced swimming motility. Overall, this study expands our knowledge of pseudomonad motility and highlights the utility of a TraDIS-based approach for analysing the functions of thousands of genes. This work sets a foundation for understanding how swimming motility may be related to the inconsistency in biocontrol bacteria performance in the field.

Gender disparities in patients undergoing extracorporeal cardiopulmonary resuscitation

Introduction

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in extracorporeal cardiopulmonary resuscitation (eCPR) has emerged as a treatment option for selected patients who are experiencing refractory cardiac arrest (CA). In the light of increasing availability, the analyses of outcome-relevant predisposing characteristics are of growing importance. We evaluated the prognostic influence of gender in patients presenting with out-of-hospital cardiac arrest (OHCA) treated with eCPR.

Methods

We retrospectively analysed the data of 377 consecutive patients treated for OHCA using eCPR in our cardiac arrest centre from January 2016 to December 2022. The primary outcome was defined as the survival of patients until they were discharged from the hospital, with a favourable neurological outcome [cerebral performance category (CPC) score of ≤2]. Statistical analyses were performed using baseline comparison, survival analysis, and multivariable analyses.

Results

Out of the 377 patients included in the study, 69 (21%) were female. Female patients showed a lower prevalence rate of pre-existing coronary artery disease (48% vs. 75%, p < 0.001) and cardiomyopathy (17% vs. 34%, p = 0.01) compared with the male patients, while the mean age and prevalence rate of other cardiovascular risk factors were balanced. The primary reason for CA differed significantly (female: coronary event 45%, pulmonary embolism 23%, cardiogenic shock 17%; male: coronary event 70%, primary arrhythmia 10%, cardiogenic shock 10%; p = 0.001). The prevalence rate of witnessed collapse (97% vs. 86%; p = 0.016) and performance of bystander CPR (94% vs. 85%; p = 0.065) was higher in female patients. The mean time from collapse to the initiation of eCPR did not differ between the two groups (77 ± 39 min vs. 80 ± 37 min; p = 0.61). Overall, female patients showed a higher percentage of neurologically favourable survival (23% vs. 12%; p = 0.027) despite a higher prevalence of procedure-associated bleeding complications (33% vs. 16%, p = 0.002). The multivariable analysis identified a shorter total CPR duration (p = 0.001) and performance of bystander CPR (p = 0.03) to be associated with superior neurological outcomes. The bivariate analysis showed relevant interactions between gender and body mass index (BMI).

Conclusion

Our analysis suggests a significant survival benefit for female patients who obtain eCPR, possibly driven by a higher prevalence of witnessed collapse and bystander CPR. Interestingly, the impact of patient age and BMI on neurologically favourable outcome was higher in female patients than in male patients, warranting further investigation.

Prognostic influence of mechanical cardiopulmonary resuscitation on survival in patients with out-of-hospital cardiac arrest undergoing ECPR on VA-ECMO

Introduction

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in extracorporeal cardiopulmonary resuscitation (ECPR) in selected patients after out-of-hospital cardiac arrest (OHCA) is an established method if return of spontaneous circulation cannot be achieved. Automated chest compression devices (ACCD) facilitate transportation of patients under ongoing CPR and might improve outcome. We thus sought to evaluate prognostic influence of mechanical CPR using ACCD in patients presenting with OHCA treated with ECPR including VA-ECMO.

Methods

We retrospectively analyzed data of 171 consecutive patients treated for OHCA using ECPR in our cardiac arrest center from the years 2016 to 2022. A Cox proportional hazards model was used to identify characteristics related with survival.

Results

Of the 171 analyzed patients (84% male, mean age 56 years), 12% survived the initial hospitalization with favorable neurological outcome. The primary reason for OHCA was an acute coronary event (72%) followed by primary arrhythmia (9%) and non-ischemic cardiogenic shock (6.7%). In most cases, the collapse was witnessed (83%) and bystander CPR was performed (83%). The median time from collapse to VA-ECMO was 81 min (Q1: 69 min, Q3: 98 min). No survival benefit was seen for patients resuscitated using ACCD. Patients in whom an ACCD was used presented with overall longer times from collapse to ECMO than those who were resuscitated manually [83 min (Q1: 70 min, Q3: 98 min) vs. 69 min (Q1: 57 min, Q3: 84 min), p = 0.004].

Conclusion

No overall survival benefit of the use of ACCD before ECPR is established was found, possibly due to longer overall CPR duration. This may arguably be because of the limited availability of ACCD in pre-clinical paramedic service at the time of observation. Increasing the availability of these devices might thus improve treatment of OHCA, presumably by providing efficient CPR during transportation and transfer.

Clinical and Liver Enzymes among the Patients with Metabolic Syndrome with or without Non Alcoholic Fatty Liver Disease attending a Tertiary Care Hospital

Metabolic syndrome is characterized by central obesity, dyslipidemia, raised blood pressure and impaired blood sugar levels. Patients with metabolic syndrome are at increased risk of type 2 diabetes and atherosclerotic cardiovascular disease. This cross-sectional observational study was carried out from January 2019 to December 2019 at the inpatient and outpatient department of BIRDEM General Hospital, Dhaka, Bangladesh. Adult subjects aged ≥18 years with metabolic syndrome (IDF criteria, 2006) were included and purposive sampling was done. A total of 242 participants were included and the mean age was 40.2±14.1 years ranging from 18-70 years. Among them, 140(57.85%) were female and 102(42.15%) were male. Out of 242 participants, 170(70.25%) subjects had Metabolic Syndrome (MetS) with Non-Alcoholic Fatty Liver (NAFLD) and 72(29.75%) subjects had metabolic syndrome without NAFLD. In the male participants, the mean waist-hip ratio (WHR) of MetS with NAFLD and MetS without NAFLD was 1.01±0.07 vs. 0.96±0.08 respectively (p-value 0.003). In female subjects, the mean waist-hip ratio (WHR) of MetS with NAFLD and MetS without NAFLD group was 0.90±0.10 vs. 0.86±0.08 respectively (p-value 0.026). MetS with NAFLD subjects were more hypertensive than MetS without NAFLD subjects (61.2% vs. 42.7%). In the MetS with NAFLD group (n=170), 11.8% was normoglycemic, 43.5% was prediabetic and 44.7% was diabetic. In the MetS without NAFLD group (n=72), 19.5% was normoglycemic, 50% was prediabetic and 30.5% was diabetic. SGPT value was significantly raised in MetS with NAFLD subjects (56.4%) than MetS without NAFLD (38.9%) subjects (p-value 0.038). SGOT value was significantly raised in MetS with NAFLD subjects (58.8%) than MetS without NAFLD subjects (41.7%); (p-value 0.005). Mean Total Cholesterol and Triglyceride were significantly raised in MetS with NAFLD subjects than MetS without NAFLD subjects (p-value 0.01). In Subjects with grade I fatty liver, mean SGPT and SGOT were 42.27±22.31 vs. 39.59±16.93 respectively. In Subjects with grade II fatty liver, mean SGPT and SGOT were 62.13±32.42 vs. 52.45±28.56 respectively. In grade III fatty liver, mean SGPT and SGOT were 51.50±32.19 vs. 41.00±17.52 respectively (p value <0.001). More than two-third of participants with metabolic syndrome had non-alcoholic fatty liver disease (NAFLD) and a significant elevation of liver enzymes than metabolic syndrome without NAFLD participants. About 85.0% of metabolic syndrome participants had glucose intolerance in the form of prediabetes and diabetes.

Hemadsorption treatment for antithrombotic drug removal in emergency cardiac surgery – cost-benefit analysis comparing patient outcomes

Background

Intraoperative hemadsorption is indicated for ticagrelor and rivaroxaban removal in patients undergoing urgent cardiac surgery and has been previously shown to reduce bleeding complications. However, whether this application is cost effective is currently unknown.

Methods

Between June 2017 and June 2021, we evaluated the outcomes of 72 consecutive patients (age 65±11 years) with acute coronary syndrome (ACS) pretreated with ticagrelor who underwent urgent coronary artery bypass grafting (CABG) at our institution. Intraoperative hemoadsorption (IH) was used in all cases (IH-Pat). We estimated the mean cost per patient, and a bootstrap analysis was performed based on individual data from the case series. We compared the results with “historical patients” who were operated under the same conditions between June 2015 and June 2017 but without IH (n=22).

Results

Bilateral internal mammary artery (BIMA) was used in 67.7% of all cases. Use of IH was associated with significantly shorter operation times (277±65 min vs. 320±75 min; P=0.014) and significantly less postoperative 24-hours chest tube drainage (277±65 mL vs. 866±262 mL; P&lt;0.001). Only two rethoracotomies (2.8%) had to be performed. In addition, patients operated without IH required significantly more blood products and had a significantly higher rate of rethoracotomy, resulting in longer ICU stays. The variable that had the highest impact on the level of cost savings was the operation duration. The overall cost saving with IH were calculated at over 4200±1100€ with operation time, ICU stay and blood product costs being the top contributors.

Conclusions

The results suggest that the clinical benefits derived from IH in ticagrelor-treated patients requiring urgent cardiac surgery patients could result in significant cost savings of over 4200±1100 € per patient.

Funding Acknowledgement

Type of funding sources: None.

Experimental acoustic scene analysis using One-Eighth spherical fraction microphone array

This paper investigates the performance of one-eighth Spherical Fraction Microphone Array through experimental measurement to analyze acoustic scenes in one-eighth of space. The array geometry is designed to be placed in a room corner at the junction of three acoustically rigid walls. Two prototypes are built with 8 and 16 microphones, respectively. The sampling strategy is discussed and a spatial aliasing analysis is carried out both analytically and by numerical simulations. The array performances are evaluated through Spherical Fraction Beamforming (SFB). This approach is based on the decomposition of the acoustic pressure field in a rigid bounded domain. The localization angular error and Directivity Index criterion are evaluated for both arrays. In a first experiment, the arrays are mounted in an eighth of space built inside an anechoic room. The results are compared with simulation and show consistency. The theoretical limitations of SFB in a rigid bounded one-eighth of space are retrieved experimentally. These limitations are also observed in a real configuration: an office room. Further investigations on SFB are also conducted in the case of a virtual scene constructed with two sound sources.

Emerging infectious bronchitis virus (IBV) in Egypt: Evidence for an evolutionary advantage of a new S1 variant with a unique gene 3ab constellation

Infectious bronchitis virus (IBV), a gamma-coronavirus, causes infectious bronchitis (IB), a major respiratory disease of chicken. Its high mutation rate in conjunction with recombination of the RNA genome constantly creates IBV variants that are difficult to control by currently available vaccines. In this study, we addressed the question whether small-scale holdings might harbor IBV variants that serve as a reservoir for newly emerging variants. Egyptian IBV isolate EGY/NR725/2016 (NR725/16) from a small-scale broiler farm was assigned to genotype I, clade 23 (S1:GI-23), based on partial S1 gene sequences and corroborated by full genome sequencing. Analysis of the S1 gene established three subclades for historical IBV strains (S1:GI-23.1, S1:GI-23.2.1 and S1:GI-23.2.2) and confirmed NR725/16 as being part of a separate fourth subclade (S1:GI-23.3). Samples from the years 2018 and 2019 revealed that the new subclade prevails in Egypt, carrying fixed mutations within the hypervariable regions (HVR) 1-3 of the S1 protein that affect two neutralization sensitive epitopes at sites 294F, 297S and 306Y (48.2) and 329R (62.1). In addition, recombination was recognized in isolate NR 725/16, with intra-subtype mixing for the entire genes 3ab and E and inter-subtype mixing for the entire gene 6b with a close match to QX like viruses of genotype GI-19. Further analysis of gene 3ab detected the homologous gene pool to NR725/16 in samples from 2013 (3ab:C) and closely related 3ab genotypes in IBV Egyptian isolates from 2016, 2018 and 2019. These data prove a flourishing exchange between poultry holdings with a common gene pool. The continued circulation of viruses harboring genes S1:GI-23.3 and 3ab:C indicates an evolutionary advantage of this combination possibly by combining antigenic escape with modulated pathogenicity to facilitate IBV spread in the vaccinated poultry population in Egypt.

P6518Radial artery dilatation to improve access and lower complication rates during coronary angiography (RADIAL): a randomized controlled trial

Background

Transradial catheterization has become the preferred access site for coronary angiography. The transradial approach is however not without challenges and complications. Cannulation is technically challenging and may require multiple cannulation attempts or access may fail. Local access site complications may occur postprocedurally.

Purpose

To explore the use of prolonged occlusion flow mediated dilatation (PO-FMD) to dilate the radial artery prior to cannulation to reduce puncture attempts, increase cannulation success and reduce access site complications in transradial coronary angiography.

Methods

1156 patients undergoing transradial coronary angiography were randomized into PO-FMD and sham PO-FMD groups. PO-FMD was achieved by a 10 minute inflation of a blood pressure cuff on the arm to above systolic pressure, followed by deflation with resultant radial artery dilation. In the sham PO-FMD group the cuff was not inflated. The operators were blinded to the intervention.

Results

580 patients were randomized to the sham PO-FMD group and 576 to the PO-FMD group. The number of puncture attempts were reduced with the use of PO-FMD, with a median number of attempts of 1 in the PO-FMD group and 2 in the sham PO-FMD group (p<0.001). Cannulation failure was reduced with PO-FMD FMD with cannulation failure rates of 2.7% in the PO-FMD group and 5.8% in the sham PO-FMD group (p=0.01). Radial artery pulsation loss (RAPL) was reduced with PO-FMD with 1.4% in the PO-FMD group and 3.8% in the sham PO-FMD group (p=0.02).

Conclusion

PO-FMD decreases puncture attempts, reduces cannulation failure rates and decreases RAPL during transradial coronary angiography.

Hong-Ou-Mandel interference between independent III-V on silicon waveguide integrated lasers

The versatility of silicon photonic integrated circuits has led to a widespread usage of this platform for quantum information-based applications, including quantum key distribution (QKD). However, the integration of simple high-repetition-rate photon sources is yet to be achieved. The use of weak-coherent pulses (WCPs) could represent a viable solution. For example, measurement device independent QKD (MDI-QKD) envisions the use of WCPs to distill a secret key immune to detector side channel attacks at large distances. Thus, the integration of III-V lasers on silicon waveguides is an interesting prospect for quantum photonics. Here we report the experimental observation of Hong-Ou-Mandel interference with 46±2% visibility between WCPs generated by two independent III-V on silicon waveguide integrated lasers. This quantum interference effect is at the heart of many applications, including MDI-QKD. This Letter represents a substantial first step towards an implementation of MDI-QKD fully integrated in silicon and could be beneficial for other applications such as standard QKD and novel quantum communication protocols.

A Multi-resolution Approach for Content-based Image Retrieval on the Grid

Objectives: Hospitals and medical centers are producing more and more data that need to be processed. Those data are confidential, heterogeneous, and limited to the geographic site where they have been produced. Unless properly anonymized, they cannot be distributed on wide area networks.

Methods: Grid technologies allow the globalization of storage and processing resources, and enable large-scale experimentations on distributed data. They constitute a promising tool to treat the different data and analyze the knowledge they contain, while offering secured access and high-performance computing capacities to the different users. Our aim is to evaluate the possibilities of grid technologies for handling medical data.

Results and Conclusions: In this paper, we focus on a breast cancer diagnosis assistance tool, based on distributed and incremental knowledge construction and a content-based image retrieval system. We analyze the different scenarios of uses of such a tool. We further propose an algorithm that indexes mammographic images for content-based query purposes. This algorithm is tested on images of different resolutions in order to reduce the indexation time and we analyze its performance with experiments on the grid.

Hemodynamic effects of sodium bicarbonate administration

OBJECTIVE

To describe the hemodynamic changes that occur with sodium bicarbonate (NaHCO₃) administration in premature neonates.

STUDY DESIGN

This retrospective study included premature neonates 23 to 31+6 weeks of gestational age who underwent continuous cardiac and cerebral monitoring as participants in prospective trials at our institution, and who received NaHCO₃ infused over 30 min in the first 24 h of life. Blood pressure (BP), heart rate, cardiac output (CO), SpO₂ and cerebral oximetry (StO₂) were captured every 2 s. A baseline was established for all continuous data and averaged over the 10 min before NaHCO₃ administration. Baseline was compared with measurements over 10 min epochs until 80 min after administration. Arterial blood gases before and within 1 h of administration were also compared. Significance was set at P<0.05.

RESULTS

A total of 36 subjects received NaHCO₃ (1.3±0.3 mEq kg^-1) in the first 24 h (14±8.5 h) of life. NaHCO₃ administration increased pH (7.23 vs 7.28, P<0.01) and decreased base deficit (-8.9 vs -6.8, P<0.01) and PaCO₂ (45 vs 43 mm Hg, P<0.05). There was a transient but significant (P<0.05) decrease in systemic BP coinciding with an increase in cerebral oxygenation without an increase in oxygen extraction. CO did not change.

CONCLUSION

Early postnatal NaHCO₃ administration does not acutely improve CO but does cause transient fluctuations in cerebral and cardiovascular hemodynamics in extremely premature infants.

Bilateral concomitant intravitreal anti-vascular endothelial growth factor injection: Experience in a Nigerian tertiary private eye care facility

OBJECTIVES

To evaluate the indication and safety profile of same-session bilateral intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF).

METHODS

This is a retrospective case series of all the patients that received same-session bilateral intravitreal anti-VEGF in Eye Foundation Hospital, Ikeja, Lagos, from March 2013 to March 2015. Data retrieved from the patients' medical records includes demographics, indications for injections, complications, and systemic comorbidities.

RESULTS

During the study period, a total of 442 injections were performed on 126 eyes of 63 patients (M:F ratio; 1.4:1) whose mean age was 55.7 ± 15.6 standard deviation years. The modal age group was 51-70 years. All the patients received injection Bevacizumab (Avastin; Genentech Inc., South San Francisco, California, USA-1.25 mg). The most common primary indication for initiating bilateral intravitreal therapy was diabetic macular edema 23 (36.5%). Mean follow-up period was 40.6 days (range: 1-364 days). A combined diabetes mellitus and hypertension accounted for most of the systemic comorbidities 28 (44.4%). Subconjunctival hemorrhage was the only complication seen in these patients with 6 (9.5%) occurring intraoperatively and 9 (14.3%) postoperatively. There was no association between intraoperative complication and age (P = 0.66) or gender (P = 0.96). Furthermore, there exist no association between postoperative complication and age (P = 0.49) or gender (P = 0.99).

CONCLUSIONS

No major systemic or ocular adverse events were noted. Given that there are potentially serious complications following anti-VEGF injection, further study with a larger number of patients will be necessary to definitively prove the safety of this treatment modality.

Do diabetic patients receiving conventional dialysis solutions benefit from peritoneal dialysis?

AIM

The study aimed to evaluate the impact of glucose-based peritoneal dialysis solutions (GBPDS) on diabetic patients on maintenance peritoneal dialysis.

METHODS

In this cross-sectional study we compared the influence of long term use of GBPDS on sixteen parameters related to the peritoneal glucose load, hydration status, inflammation, blood pressure, lipid profile and left ventricular mass in 45 stable PD patients (20 diabetic and 25 non-diabetic) receiving GBPDS.

RESULTS

At 24 months HbA1c, peritoneal glucose load index (PGLI), fluid overload (FO), plasma BNP, hsCRP and IL-6 levels, WBC count, blood pressure, triglycerides, LDL-C and left ventricular mass index (LVMI) were higher in diabetic patients compared to non-diabetic subjects (P ≤ 0.04). Of 16 tested variables, 14 had deteriorated at 24 months in diabetic patients. PGLI values > 3 g/kg/day or FO > 1.0 L were associated with abnormal values of HbA1c, plasma BNP, CRP and plasma IL-6 levels. 60% of diabetic patients had PGLI > 3g/kg/day compared to 32% of non-diabetic patients (P < 0.001). Seventy per cent of diabetic patients had FO > 1.0 L compared to 28% of non-diabetic patients (P < 0.001). Only 12% of diabetic patients had nocturnal blood pressure dipping compared to 45% of non-diabetics (P = 0.03). 57.8% of the studied patients had increased LVMI. Diabetic patients had higher LVMI values compared to non-diabetics (P < 0.001). The presence of DM was found to be the most powerful predictor for the development of LVH (P < 0.001).

CONCLUSION

Utilization of GBPDS in diabetic PD patients may be associated with substantial adverse consequences affecting glycemic control, hydration status, lipid profile, inflammation, blood pressure control and LVM.

Dihedron dielectric loaded surface plasmon athermal polarization converter

We investigate numerically a novel plasmonic polarization converter relying on the excitation of a so-called dihedron dielectric loaded plasmon polariton. The dihedron dielectric loaded waveguide consists of a dielectric ridge implemented at the inner corner of a metal-coated dielectric step. For a dielectric ridge with a square cross section, the plasmon polariton modes supported by each side of the metallized step hybridize to create supermodes with crossed polarizations. We show that the two supermodes can be operated in a dual-mode interferometer configuration to perform an efficient (24 dB) TE-TM/TM-TE polarization conversion over typical distances below 30 μm at telecommunications wavelengths. In addition, on the basis of the thermo-optical properties of our device, we find that the dihedron plasmonic polarization converter is temperature insensitive.