Mechanical Power Correlates With Lung Inflammation Assessed by Positron-Emission Tomography in Experimental Acute Lung Injury in Pigs

Background: Mechanical ventilation (MV) may initiate or worsen lung injury, so-called ventilator-induced lung injury (VILI). Although different mechanisms of VILI have been identified, research mainly focused on single ventilator parameters. The mechanical power (MP) summarizes the potentially damaging effects of different parameters in one single variable and has been shown to be associated with lung damage. However, to date, the association of MP with pulmonary neutrophilic inflammation, as assessed by positron-emission tomography (PET), has not been prospectively investigated in a model of clinically relevant ventilation settings yet. We hypothesized that the degree of neutrophilic inflammation correlates with MP.Methods: Eight female juvenile pigs were anesthetized and mechanically ventilated. Lung injury was induced by repetitive lung lavages followed by initial PET and computed tomography (CT) scans. Animals were then ventilated according to the acute respiratory distress syndrome (ARDS) network recommendations, using the lowest combinations of positive end-expiratory pressure and inspiratory oxygen fraction that allowed adequate oxygenation. Ventilator settings were checked and adjusted hourly. Physiological measurements were conducted every 6 h. Lung imaging was repeated 24 h after first PET/CT before animals were killed. Pulmonary neutrophilic inflammation was assessed by normalized uptake rate of 2-deoxy-2-[18F]fluoro-D-glucose (KiS), and its difference between the two PET/CT was calculated (ΔKiS). Lung aeration was assessed by lung CT scan. MP was calculated from the recorded pressure–volume curve. Statistics included the Wilcoxon tests and non-parametric Spearman correlation.Results: Normalized 18F-FDG uptake rate increased significantly from first to second PET/CT (p = 0.012). ΔKiS significantly correlated with median MP (ρ = 0.738, p = 0.037) and its elastic and resistive components, but neither with median peak, plateau, end-expiratory, driving, and transpulmonary driving pressures, nor respiratory rate (RR), elastance, or resistance. Lung mass and volume significantly decreased, whereas relative mass of hyper-aerated lung compartment increased after 24 h (p = 0.012, p = 0.036, and p = 0.025, respectively). Resistance and PaCO2 were significantly higher (p = 0.012 and p = 0.017, respectively), whereas RR, end-expiratory pressure, and MP were lower at 18 h compared to start of intervention.Conclusions: In this model of experimental acute lung injury in pigs, pulmonary neutrophilic inflammation evaluated by PET/CT increased after 24 h of MV, and correlated with MP.

Energetic scaling in microbial growth

Microbial growth is a clear example of organization and structure arising in nonequilibrium conditions. Due to the complexity of the microbial metabolic network, elucidating the fundamental principles governing microbial growth remains a challenge. Here, we present a systematic analysis of microbial growth thermodynamics, leveraging an extensive dataset on energy-limited monoculture growth. A consistent thermodynamic framework based on reaction stoichiometry allows us to quantify how much of the available energy microbes can efficiently convert into new biomass while dissipating the remaining energy into the environment and producing entropy. We show that dissipation mechanisms can be linked to the electron donor uptake rate, a fact leading to the central result that the thermodynamic efficiency is related to the electron donor uptake rate by the scaling law η∝μED−1/2 and to the growth yield by η∝Y4/5. These findings allow us to rederive the Pirt equation from a thermodynamic perspective, providing a means to compute its coefficients, as well as a deeper understanding of the relationship between growth rate and yield. Our results provide rather general insights into the relation between mass and energy conversion in microbial growth with potentially wide application, especially in ecology and biotechnology.

Review of Prenatal Aneuploidy Screening Uptake Rate and Trends in Iran, and Developed Countries

: Prenatal screening of different anomalies including chromosomal aneuploidies have become a part of routine pregnancy care in most countries around the world. These tests can help pregnant mothers to have informed decisions. In this study we gathered relevant scientific and governmental/official data about uptake rate of these screenings in different developed countries and Iran. We have tried to use the latest articles and reports, and also consider to the global trend of screening and abortion policies in developed countries. Also, some pitfalls when comparing prenatal screening of different countries will be explained. These data can help to have a better insight about Iran’s prenatal screening status when compared with developed countries to improve public health policies.

Comparison of Reinforcement Cartilage Graft and Temporalis Fascia Graft in Type 1 Tympanoplasty

Background: Chronic otitis media (COM) is the long-standing infection of a part or whole of middle ear cleft characterized by ear discharge and perforation. It is the commonest ear problem in adult and children. Most common presenting symptoms are ear discharge, mild to severe hearing loss, sometimes tinnitus even vertigo. Treatment of COM is mainly operative. Inactive mucosal variety of COM presents with the perforation in tympanic membrane with non-inflamed middle ear mucosa. The treatment of inactive mucosal variety of COM is Type 1tympanoplasty. It can be done by conventional temporalis fascia or cartilage graft. Both have some merits and demerits. Objective: To compare the the outcomes between reinforcement cartilage graft and temporalis fascia graft in type -1 tympanoplasty. Methods: 86 (43 patients in each group) patients with COM (inactive mucosal) who were admitted in the department of Otolaryngology – Head and Neck Surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka from January 2018 to June 2019, and had fulfilled the inclusion and exclusion criteria were selected for the study. History, examinations, investigations were done. All patients underwent type 1 tympanoplasty. Prior to surgery relevant investigations were done and informed written consent was taken from all patients. In Group-A reinforcement cartilage tympanoplasty cases and in Group-B temporalis fascia tympanoplasty cases were placed. Post-operative graft uptake rate and hearing gain were compared in two groups Results: The surgical outcomes between reinforcement cartilage tympanoplasty in comparison with temporalis fascia tympanoplasty showed no significant difference of graft uptake rate and hearing gain. Conclusion: Cartilage tympanoplasty has been practised for reconstruction of perforated tympanic membrane in COM since long with variable results. Graft uptake rate in cartilage reinforcement is comparatively better than temporalis fascia graft. So, reinforcement cartilage graft can be adopted as an alternative to temporalis fascia graft in type- I tympanoplasty. Bangladesh J Otorhinolaryngol 2021; 27(2): 104-110

Social and Behaviour Change Communication Intervention Improves Coverage and Acceptance of Ivermectin Mass Drug Administration in Onchocerciasis Endemic Communities in Ghana: A Quasi Experimental Design

BackgroundPoor community awareness and social mobilization serve as a major barrier by increasing absenteeism and downplaying the relevance of the ivermectin mass distribution by community members. Inadequate awareness also creates confusion among community members especially when one intervention is mistaken for the other. MethodsWe designed a targeted Social and Behaviour Change Communication (SBCC) intervention with clearly defined and tailored messages of ivermectin MDA program targeting onchocerciasis in endemic communities in Ghana. Quasi experiment was conducted with a total sample size of 2008 at baseline and 2113 at endline. ResultsAt baseline, 63.9% respondents did not receive Ivermectin during the previous year (2019) MDA programme and more than half of them (53.3%) were not aware of the drug distribution. The communities that received the intervention at endline revealed a significantly higher increase in coverage (SATT=0.123, 95% CI=0. 0.073, 0.173, p<0.001). At baseline, uptake rate of 91.0% was recorded. Post the intervention, there was an increase in the proportion of respondents who ingested the MDA drugs (ivermectin) from 91.0% to 95.45%. Previous uptake of MDA drugs (AOR=10.67; 95%CI: 5.59-20.38, p<0.001), Perceived benefit of MDA drug (AOR=4.13; 95%CI: 1.69-10.15, p<0.001) and being aware of the MDA programme (AOR=2.28; 95%CI: 1.00-5.02, p=0.049) was associated with improved receipt of Ivermectin. ConclusionThe findings of this study reveal that SBCC intervention improves ivermectin coverage and uptake rate in mass drug administration. Further research with technological innovations which can enhance SBCC is recommended taking hind sight of the limitations of the study due to the COVID-19 pandemic.

OUTCOMES OF CIRCUMFERENTIAL V/S ANTERIOR TUCKING TYMPANOPLASTY TECHNIQUE IN INACTIVE MUCOSAL CHRONIC OTITIS MEDIA WITH SUBTOTAL PERFORATIONS: A PROSPECTIVE OBSERVATIONAL STUDY

Objective: The objective of the study is to compare circumferential versus anterior tucking underlay tympanoplasty technique. Methods: In this prospective observational study, 100 patients with chronic otitis media (Inactive mucosal type) were included, who were randomly allocated in two groups; Group I which comprised of 50 patients in which tympanoplasty with anterior tucking was done, and Group II comprised of 50 patients in which circumferential flap tympanoplasty was done. Improvement in the hearing gain and graft uptake success rate was compared. Results: The mean air-bone gap (ABG) changed from 28.74 dB to 11.52 dB after anterior tucking with a mean change of 17.22 dB and this change was found to be statistically significant (p<0.001). Similarly, the mean ABG changed from 28.92 dB to 11.86 dB after a circumferential flap with a mean change of 17.06 dB and this change was also found to be statistically significant (p<0.001). There was a slightly better improvement (17.22 dB) in the anterior tucking group as compared to the circumferential flap (17.06 dB). This difference was, however, not found to be statistically significant (p=0.830). Three-month graft uptake rate in the anterior tucking group was found 92% and in the circumferential group was 94%. (p>0.05). Conclusions: Our study concluded that both techniques have almost the same results with good graft uptake. Results of hearing improvements in both techniques were also comparable.

Study on the Balance of Oxygen in Supply and Demand in Wastewater Treatment Plant

In order to accurately evaluate the comprehensive operation efficiency of aerobic biological treatment system in wastewater treatment plants (WWTPs), the process state aeration performance tester and the specific oxygen uptake rate online monitoring device were used to measure the oxygenation performance and the activated sludge performance in aeration tank, and the comprehensive operation efficiency of aerobic tank was evaluated by combining physical-chemical indexes and water quality analysis of the treatment system. The results showed that the oxygen transfer efficiency (OTE) of aerators under process state are reduced by 13.07% and 14.48% respectively compared with that in clean water in the No.3-tank and No.6-tank, and the aeration uniformity index (IAU) is 4.86 and 1.46 respectively. The oxygen uptake rate (OUR) in the third corridor decreased significantly, but dissolved oxygen (DO) was a high level. Oxygen in supply (Qs) was much greater than oxygen in demand (Cs), which have resulted a large waste of energy consumption. Finally, the subsection regulation strategy was proposed based on the principle of oxygen balance. The results of this study will not only help the WWTP to achieve energy-saving and consumption-reducing, but also stable operation.