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Is secondary tracheomalacia associated with persistent lower respiratory tract inflam...
Antonino Capizzi
Michela Silvestri

Antonino Capizzi

and 3 more

December 13, 2020
Background. In secondary tracheomalacia due to mediastinal vascular anomalies one of the most prevalent symptom is recurrent lower respiratory tract (LRT) infections, related to defective airway clearance. Whether this condition could result in persistent LRT inflammation and subclinical infection is not known. Patients and methods. Children with tracheomalacia due to mediastinal vascular anomalies, recurrent (>3/y) LRT infections were evaluated while in stable condition. Computed tomography (CT) scan and bronchoscopy with bronchoalveolar lavage (BAL) were performed. Results. 31 children were included in the study: 21 with aberrant innominate artery (AIA), 4 with right aortic arch (RAA) and 1 with double aortic arch (DAA) and 5 with AIA associated with RAA. Cytological evaluation of BAL fluid showed increased neutrophil percentages and normal lymphocyte and eosinophil proportions. Microorganism growth was detected in 35.5% of BAL samples, with a bacterial load >105 colony-forming-units (CFU)/mL only in 10,2% of them. Most isolates were positive for Haemophilus influenzae, followed by Streptococcus pneumoniae, Group A β-hemolytic streptococci and Moraxella catarrhalis. Chest CT scan demonstrated the presence of bronchiectasis in 13% of the children, of which only one had a positive BAL culture for Haemophilus influenzae. Conclusions. Only in a small subgroup of children, persistent neutrophilic alveolitis was associated with a significant bacterial load and the presence of bronchiectasis. Because most pathogens detected in BAL samples cultures can produce biofilms, caution should be used in inappropriate antibiotic prescription in these patients that, chiefly in those with bronchiectasis, in which chest physiotherapy can be of great benefit.
Bispectral Index Values of Natural Sleep and its Use in Sleep Endoscopy
Gokhan Yalciner
Mehmet Babademez

Gokhan Yalciner

and 6 more

December 13, 2020
OBJECTİVE: To investigate the bispectral index values of normal sleep stages PATİENTS and METHOD: Simultaneous polysomnography and bispectral index recordings of 21 patients who underwent polysomnography for diagnosis of obstructive sleep apnea were analyzed for determining the BIS values of normal sleep stages. RESULTS: BIS values are found sensitive in reflecting the various stages of natural sleep except for REM and stage N2. REM and stage N2 BIS values were close to each other. CONCLUSION: BIS is sensitive for the evaluation of the stages of natural sleep and BIS values decreases as the sleep stages becomes deeper
Auricular complications following temporal bone resection for temporal bone malignanc...
Noritaka Komune
Satoshi Matsuo

Noritaka Komune

and 19 more

December 13, 2020
Abstract: Objective: Sacrificing the auricle has severe postoperative impacts on patients with temporal bone malignancy who have undergone en bloc temporal bone resection. The auricular complications following en bloc temporal bone resection remain unclear. Therefore, this study aimed to examine auricular complications following en bloc temporal bone resection and reveal the associated risk factors. Study Design: Case series with chart review. Setting: Single tertiary care medical center Participants: Our study includes all cases who underwent en bloc temporal bone resection with preserved auricle for temporal bone malignancy from January 1993 to July 2020. The resulting dataset contained 64 patients during the review period. Main outcome measures: We examined the relationship of auricular complications with surgical procedures and patient profiles. Results: Three of 64 cases (4.7%) showed postoperative auricular complication. The cause in all three cases was venous congestion. Postoperative bloodletting to relieve the congestion effectively salvaged the auricle in two of these cases. Insufficient bloodletting to relieve the auricular congestion in the remaining case led to auricular necrosis. Pre-/infra-auricular lymph node dissection is correlated with auricular complications with statistical significance. Conclusions: Temporal bone resection causes auricular congestion due to vascular insufficiency, particularly insufficient venous outflow. An immediate and continuous application of bloodletting can improve venous drainage after temporal bone resection to prevent auricle necrosis.
The true relative financial cost of Planned Caesarean Birth (PCB) versus Planned Vagi...
Jonathan West
Myles Taylor

Jonathan West

and 2 more

December 13, 2020
OBJECTIVE: To determine the true financial costs of Planned Caesarean Section and Planned Vaginal Birth in England for the year 2018/19 after accounting for litigation and compensation for harm (LCFH) DESIGN: Sensitivity analysis BACKGROUND: Average base costs per delivery remitted to NHS maternity providers for Planned Caesarean Birth (PCB) and Planned Vaginal Birth (PVB) in 2018/19 were £3,948 and £3,270 respectively leading to a perception that PCB is more costly than PVB. Indemnity costs potentially related to planned mode of delivery, however, add an average of £1,571/delivery to overall costs. METHOD: Retrospective analysis of costs according to planned mode of birth was performed based on data and previous research published by NHS Resolution and NHS England. Weighting of results according to PCB and PVB rates was performed in a manner similar to the sensitivity analysis of PCB v PVB (without accounting for LCFH) performed by the National Institute for Health and Care Excellence (NICE) in 2011 RESULTS: Additional costs of LCFH resulted in revised costs of £4,245 and £5,030 for PCB and PVB respectively – a cost advantage of £785 per delivery in favour of PCB. CONCLUSION: Providers should not be discouraged from offering or women refused PCB on grounds of cost.
The Effect of Pulmonary Rehabilitation Program on Work Productivity and Clinical Para...
Mazlum Serdar Akaltun
Ozlem Altindag

Mazlum Serdar Akaltun

and 2 more

December 13, 2020
Objectives: The objective of the present study was to investigate the effect of the Pulmonary Rehabilitation Program on work productivity, disease activity, functional status, quality of life, Respiratory Function Tests (RFTs), physical capacity,and depression in Ankylosing Spondylitis (AS) patients. Method: Twenty-five patients diagnosed with AS were included in the study. The disease severity was evaluated with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), functional status was evaluated with Bath Ankylosing Spondylitis Functional Index (BASFI), and quality of life was evaluated with AS-Related Quality of Life scale (ASQOL). Physical capacity was evaluated with the 6-Minute Walking Test (6MWT), depression level was evaluated with Beck Depression Scale (BDS),and work productivity was evaluated with Spondyloartropathy Work Productivity and Activity Impairment (WPAI-SpA) Survey. RFT was evaluated with spirometry measurement. The patients were included in the Pulmonary Rehabilitation Program for 8 weeks. Results: A total of 30% of the patients who were included in the study were unemployed; 35% of them were on and below hunger limit; 25% were on and below poverty line; and 40% were on normal income line. No significant changes were detected in the RFTs after the exercise program in AS patients (p > 0.05), but significantly improvements were detected in the BASDAI, BASFI, WPAI, 6MWT, ASQOL and BDS scales (p <0.001). Conclusion: Pulmonary Rehabilitation Program was found to be an effective method of improving work productivity in AS patients. Also, the Pulmonary Rehabilitation Program has positive effects on disease activity, functional status, physical capacity, depression level, and quality of life.
Chromosome-level genome assembly of the bean bug Riptortus pedestris
Hai-Jian Huang
Yu-Xuan Ye

Hai-Jian Huang

and 9 more

December 13, 2020
The bean bug (Riptortus pedestris) causes great economic losses of soybeans by piercing and sucking pods and seeds. Although R. pedestris has become the focus of numerous studies associated with insect–microbe interactions, plant–insect interactions, and pesticide resistance, a lack of genomic resources has limited deeper insights. In this study, we report the first R. pedestris genome at the chromosomal level using PacBio, Illumina, and Hi-C technologies. The assembled genome was 1.193 Gb in size with a contig N50 of 13.97 Mb. More than 95.7% of the total genome bases were successfully anchored to 6 unique chromosomes, with the scaffold N50 reaching 181.34 Mb. Genome resequencing of male and female individuals and chromosomic staining demonstrated that the sex chromosome system of R. pedestris is XO, and the shortest chromosome is the X chromosome. In total, 21,562 protein-coding genes were predicted, 21,320 of which were validated as being expressed in different tissues or different developmental stages. Evolutionary analysis demonstrated that R. pedestris and Oncopeltus fasciatus formed a sister group and split ∼35 million years ago. Additionally, a 5.04 Mb complete genome of symbiotic Serratia marcescens Rip1 was assembled, and the virulence factors that account for successful colonization in the host midgut were identified. The high-quality R. pedestris genome provides a valuable resource for further research, as well as for the pest management of bug pests.
Ultrasound performed right after birth can predict the respiratory support needs of n...
Guannan Xi
Jiale Dai

Guannan Xi

and 6 more

December 13, 2020
Abstract Background Lung ultrasound (LUS) has been used to diagnose neonatal respiratory diseases. However, few simple method has been reported to predict respiratory support needs(RSN). Our aim was to determine the diagnostic accuracy of a semiquantitative LUS assessment method predicting respiratory support need. Methods We conducted a prospective diagnostic accuracy study following the STARD (Standards for the Reporting of Diagnostic Accuracy Studies) guidelines at a tertiary level academic hospital between 2019 and 2020. After birth, infants were transferred to a monitoring room to determine NICU treatment need. 310 late preterm and term infants with respiratory symptoms enrolled. The LUS assessment was performed for each participant at one of the following times: 0.5 h, 1 h, 2 h, 4 h, and 6 h after birth. Reliability was tested by ROC analysis. Surfactant administration and other RSNs were based on the 2019 European guidelines as well as the infant’s clinical condition. Results 74 have RSN, and 236 were healthy according to a 3-day follow-up confirmation. Six LUS imaging patterns were found. Two “high-risk” patterns were highly correlated with RSN(area under the curve (AUC) = 0.95; 95% CI, 0.92-0.98, p<0.001). This accuracy is supported by the AUC of “low-risk” patterns (0.89, 95% CI, 0.85-0.93, p<0.001). The predictive value of LUS is greater than that of only using respiratory symptoms (e.g., respiratory rate) (AUC of LUS vs AUC of respiratory rate, p<0.01). Conclusions LUS is a useful tool to predict RSN and is more reliable than assessments based on respiratory symptoms alone.
Well posedness for the Kawahara equation on the half-line
Boling Guo
fengxia liu

Boling Guo

and 1 more

December 13, 2020
We study the low-regularity properties of the Kawahara equation on the half line. We obtain the local existence, uniqueness, and continuity of the solution. Moreover, We obtain that the nonlinear terms of the solution are smoother than the initial data.
Trade-offs between reducing complex terminology and producing accurate interpretation...
Rodriguez-Ezpeleta, Naiara
Olivier Morissette

Naiara Rodriguez-Ezpeleta

and 25 more

December 13, 2020
In a recent paper, “Environmental DNA: What’s behind the term? Clarifying the terminology and recommendations for its future use in biomonitoring”, Pawlowski et al. argue that the term eDNA should be used to refer to the pool of DNA isolated from environmental samples, as opposed to only extra-organismal DNA from macro-organisms. We agree with this view. However, we are concerned that their proposed two-level terminology specifying sampling environment and targeted taxa is overly simplistic and might hinder rather than improve clear communication about environmental DNA and its use in biomonitoring. Not only is this terminology based on categories that are often difficult to assign and uninformative, but it ignores what is in our opinion the most important distinction within eDNA: the type of DNA (organismal or extra-organismal) from which ecological interpretations are derived.
Artificial Neural Network Approach for Solving Fuzzy Fractional order initial value p...
Somayeh Ezadi
Tofigh Allahviranloo

Somayeh Ezadi

and 1 more

December 13, 2020
This paper aims to solve the celebrated Fuzzy Fractional Differential Equations (FFDE) using an Artificial Neural Network (ANN) technique. Compared to the integer order differential equation, the proposed FFDE can better describe several real application problems of various physical systems. To accomplish the aforementioned aim, the error back propagation algorithm and a multi-layer feed forward neural architecture are utilized using the unsupervised learning in order to minimize the error function as well as the modification of the parameters such as weights and biases. By combining the initial conditions with the ANN, output provides an appropriate approximate solution of the proposed FFDE. Then, two illustrative examples are solved to confirm the applicability of the concept as well as to demonstrate both the precision and effectiveness of the developed method. By comparing with some traditional methods, the obtained results reveals a close match that confirms both accuracy and correctness of the proposed method.
3D imaging of ZnO NP distribution and ROS accumulation in MCF-7 cells and quantificat...
Aishee Dey
Gare Suman

Aishee Dey

and 6 more

December 12, 2020
Abstract Generally, investigations on nanomedicine involve conventional imaging techniques for obtaining static images on nanoparticle internalization at a single time point where various phases can be overlooked. In contrast, 3D live-cell imaging can be used for obtaining cellular retention of drugs at various phases, and cells can be followed for days. This article demonstrates the application of time-lapse microscopy in the investigation of Poly-L-lysine coated ZnO nanoparticle dynamics. In this work, a laser scanning confocal microscope has been employed to quantify the dynamics of internalization particles and reactive oxygen species generation (ROS) using volumetric imaging. Firstly, we show that simultaneous spatial mapping of nanoparticle uptake in MCF-7 cells and ROS in a single cell can be used to identify the interdependence between the accumulation of particles and ROS generation. Secondly, monitoring of ROS formation and cytotoxicity using the same imaging platform offers an advantage over monitoring these parameters using various instruments. Finally, the ability of the fluorescent particles in inducing a significant reduction in cell viability suggests its potential to be used as a therapeutic agent. The proposed framework opens up a new avenue of research for investigating mechanistic aspects of ZnO particle adsorption in vitro through long term imaging. Keywords: Fluorescent ZnO particle, Time-lapse microscopy, 3D Live-cell imaging, laser scanning confocal microscope, Reactive oxygen species
Drug Metabolism in Severe Chronic Obstructive Pulmonary Disease: A Phenotyping ‘Cockt...
Richard McNeill
Mei Zhang

Richard McNeill

and 3 more

December 12, 2020
Aims To evaluate the effect of severe chronic obstructive pulmonary disease (COPD) on drug metabolism by comparing the pharmacokinetics of patients with severe COPD with healthy volunteers and using the modified ‘Inje’ drug cocktail. Methods This was a single-centre pharmacokinetic study with 12 healthy participants and 7 participants with GOLD D COPD. Midazolam 1 mg, dextromethorphan 30 mg, losartan 25 mg, omeprazole 20 mg, caffeine 130 mg, and paracetamol 1000 mg were simultaneously administered and intensive pharmacokinetic sampling was conducted over 8 hours. Drug metabolism by CYP3A4, CYP2D6, CYP2C9, CYP2C19, CYP1A2, UGT1A6 and UGT1A9 in participants with COPD were compared with phenotypes in healthy controls. Results The oral clearance (95% CI) in participants with COPD relative to controls was: midazolam 63% (60-67%), dextromethorphan 72% (40-103%), losartan 53% (52-55%), omeprazole 35% (31-39%), caffeine 52% (50-53%), and paracetamol 73% (72-74%). There was a five-fold increase in AUC for omeprazole and approximately two-fold increases for caffeine, losartan, dextromethorphan, and midazolam. The AUC of paracetamol, which is mostly glucuronidated, was increased by about 60%. Conclusion Severe COPD is associated with a clinically significant reduction in drug clearance. This may be greater for cytochrome P450 substrates than for glucuronidated drugs. This supports reduced starting doses when prescribing for patients with severe COPD.
COVID-19's Effect on Regions Related to their Political Partisanship
Ryder Sousa

Ryder Sousa

December 16, 2020
    Two prevention methods to help slow the spread of COVID-19 are wearing a mask and social distancing\cite{treatment}. Within today's climate in the United States it's hard for opinions to remain independent of politics, and masking up and social distancing are no different. There are multiple studies and articles I've seen that produce evidence of republicans being less-likely to follow mask or social distancing recommendations. Perhaps political affiliation doesn't play as big of a role in COVID-19 cases as certain overly-general statements make seem. In my very small sample of republican and democrat counties from different regions of the country, I found that the republican counties did not have significantly more COVID-19 counties. In fact, in the counties I looked at the republican counties tended to have less cases than the democrat ones.
Cause conseguenze ed azioni per la sostenibilità ambientale: il rumore nei centri urb...
Davide Zottoli
Ida Pia Parzanese

Davide Zottoli

and 2 more

February 26, 2021
L’inquinamento acustico rappresenta ad oggi uno dei maggiori problemi nei centri urbani dove gli innumerevoli suoni causati dalle diverse attività, generano rumori che interferiscono con la qualità della vita. Il fastidio provocato arreca molteplici disturbi come l'incapacità di comunicazione e l'impossibilità di dormire che pregiudicano lo stato di benessere fisico, mentale e sociale di ogni individuo. Le sorgenti acustiche sono incentivate dal progresso tecnologico dei centri urbani e dall’infrastrutturazione degli stessi dovuta all'aumento demografico. L’analisi del controllo dei livelli acustici trova applicazione in un caso studio nell’ambito del monitoraggio del traffico veicolare del viadotto San Giorgio. Questo studio, attraverso l’attenta indagine del sito, ha consentito l’abbassamento del livello sonoro emesso dal ponte viario con la realizzazione di opere di mitigazione acustica.
Effectiveness of ozone therapy in addition to conventional treatment on mortality in...
Şahin Çolak
burcu genç yavuz

Şahin Çolak

and 6 more

December 12, 2020
Aim In this study, we aimed to investigate the effectiveness of ozone therapy, which is one of the integrative medicine applications that has been used safely for many years, on the prevalence of mortality in patients receiving COVID-19 treatment. Methods This was a prospective, controlled study conducted on patients with COVID-19 who were hospitalized in Health Sciences University, Haydarpasa Numune Training and Research Hospital. In this study, 55 patients were included. The patients were divided into two groups as the ozone group and the control group. Ozone therapy (major autohemotherapy) was applied to 37 patients who were being treated with the appropriate COVID-19 treatment protocol determined by the infectious diseases committee of our hospital. The ozone treatment protocol consisted of seven sessions (1 session/day) of intravenous ozone administration, applied in a volume of 100 mL and a concentration of 30 μg/mL. Only the conventional COVID-19 treatment protocol was applied to 18 patients in the control group. Clinical follow-up was performed until the discharge of the patients from the hospital with successful treatment or until the mortality occurred. Factors affecting mortality were analyzed using univariate regression analysis. Results Intensive care unit (ICU) hospitalization was required in six of 37 patients who were treated with ozone (16.2%), while four of 18 patients in the control group required ICU treatment (22.2%) (p = 0.713). When the mortality rates between the two groups were compared, mortality was lower in the ozone group (p = 0.032). As a result of univariate logistic regression analysis performed to determine the factors affecting mortality, treatment without ozone therapy was determined as a risk factor for mortality (OR:0.149, 95%CI 0.026-0.863, p=0.034). Conclusion In this study, we demonstrated that administration of ozone therapy along with the conventional medical treatment in patients hospitalized for COVID-19 could reduce mortality.
Bronchopulmonary Dysplasia: A Historical Perspective
Julian Allen
Howard Panitch

Julian Allen

and 1 more

December 12, 2020
Bronchopulmonary dysplasia (BPD) was first described by Northway et al in 1967. This article describes the evolution of our understanding of the pathophysiology of BPD and the approaches to treatments of this illness developed over the past fifty years. These interventions had their roots in the understanding of the principles of the surface tension present at air- liquid interfaces, which were developed over 150 years before BPD’s initial description. Improving outcomes in neonatal care have led to greater survival of preterm and very preterm infants, and to an evolution of the pathogenesis and pathology of BPD, from an illness caused primarily by barotrauma and oxygen toxicity to one of interruption of lung development. While the incidence of BPD has remained about the same in recent decades, this is because survival of infants born at lower gestational ages is increasing. Understanding of molecular, genetic and physiologic mechanisms has led to newer treatments that have mitigated some of the harmful effects of prolonged mechanical ventilation. Recognition of BPD as a chronic multi-system disease has resulted in further improvements in care after discharge from neonatal intensive care. Since many of the origins of chronic obstructive lung disease in adults are based in childhood respiratory illnesses, improving outcomes of BPD in infancy and childhood will undoubtedly lead to improved respiratory outcomes in the adults that these children will become.
Longitudinal Outcomes of Cardiogenic Shock Patients Undergoing Conventional Cardiac S...
Nicholas Hess
Ibrahim Sultan

Nicholas Hess

and 4 more

December 12, 2020
Background: Cardiogenic shock is a known risk factor for early mortality following conventional cardiac surgery, however its impact on longitudinal outcomes is less established. This study evaluated longer-term outcomes of conventional cardiac surgery in patients with cardiogenic shock. Methods: This was a retrospective review of conventional cardiac operations performed in patients presenting with cardiogenic shock between 2010 and 2020. The primary outcome was survival, and secondary outcomes included postoperative complications, and rates of heart failure readmission. Multivariable Cox proportional hazards modeling was conducted to identify risk-adjusted predictors of mortality. Results: 604 patients were included, representing 4% of all cardiac cases. Median follow up was 4.3 (IQR 0.3-6.8) years. Aortic root repair/replacement (31.6%) was most commonly performed. 11.1% of patients required preoperative cardiopulmonary resuscitation. Bridging modalities included intravenous inotropes (35.4%), intra-aortic balloon pump (33.4%), Impella (0.5%), or venoarterial extracorporeal membrane oxygenation (3.3%). Operative mortality was 21.5%. Complications included reoperation (24.3%), stroke (15.9%) renal failure (19.2%), and prolonged ventilation (47.9%). Unadjusted 1- and 5-year survival were 71.7% and 62.1%. Risk-adjusted preoperative predictors for mortality included peripheral vascular disease (HR 1.75, 95% CI 1.23-2.49), dialysis dependency (HR 6.30, 95% CI 3.77–10.51) and increasing age (HR 1.02, 95% CI 1.02–1.04). Three patients eventually underwent ventricular assist device implantation and no patients underwent heart transplantation. Conclusions: Despite high initial rates of morbidity and mortality following conventional cardiac surgery in patients presenting with cardiogenic shock, 62% survive to 5 years and most do not require heart failure readmission or advanced heart failure surgical therapy.
“Sleeve” Sinus Valsalva Repair in Patients with Acute Type A Aortic Dissection
Laichun Song
Yang Gao

Laichun Song

and 5 more

December 12, 2020
Purpose. The optimal surgical strategy of aortic root in acute type A aortic dissection (ATAAD) is controversial. The aim of this study was to evaluate the feasibility and safety of “Sleeve” sinus Valsalva repair for AAD limited to the non-coronary sinus or partial left and right coronary sinus without involvement coronary artery ostia. Methods: From Sep 2016 to Mar 2019, 20 patients with AAD involving non-coronary sinus or partial left and right coronary sinus Valsalva underwent “Sleeve” sinus Valsalva repair . Multi slice spiral computed tomography angiography (MSCT) and three dimensional reconstruction were routinely performed in all patients to assess the maximal diameters of each segment of the aorta. Results. There was no early death in hospital and one death during the 30-day postoperative period. Re-thoracotomy due to bleeding was necessary in only 1 patient and no bleeding was related to the proximal anastomosis. The post-operative drainage was 390.5±229.3mL. During the following-up, the echocardiography showed the normal sinus of Valsalva and aortic valvular function. The computed tomography angiography showed normal aortic root without endovascular leak or dissection around the sinus of Valsalva. All patients were free from reoperation. Conclusions. “Sleeve” sinus Valsalva repair with Dacron patch for aortic dissection limited to the non-coronary sinus or partial left and right coronary sinus without involvement coronary artery ostia was technically feasible and safe.
Fetal lung fluid: Not the same as amniotic fluid
Hemananda Muniraman

Hemananda Muniraman

December 12, 2020
Fetal lung fluid: Not the same as amniotic fluidAuthor: Hemananda Muniraman MBBS, FAAP, FRCPCHAffiliations:Creighton University School of Medicine, Phoenix Campus, Arizona, USCorresponding Author: Hemananda Muniraman, MBBS, FAAP, FRCPCHAssistant Professor of Pediatrics Affiliate, Creighton University School of MedicinePhoenix Campus, 350 W Thomas Rd, Phoenix, AZ, US 85013Email; Hemu_Muniraman@mednax.com, Phone: +16022564628 Fax: +16026276325Conflict of Interest Disclosure: I have no conflicts of interest relevant to this article to disclose. Funding/Support.No funding to be reportedKey words: Extreme preterm, neonates, pneumatocele, fetal lung fluidDear Dr MurphyEditor in chief, Pediatric PulmonologyI read with interest the recently published article “Pulmonary pneumatoceles in neonates” by Dr Rocha. [1] It is a well written comprehensive review of pulmonary pneumatoceles in neonates and an important resource for the clinicians in decision making, that I found to be very insightful whilst recently managing an extreme preterm with a large pneumatocele.However, I wanted to bring attention to a statement in the introduction where the author states that the “preterm infants’ lungs are filled with amniotic fluid”. This is not accurate and appears to be a common misconception, particularly among medical students and junior residents despite recognition of fetal lung fluid as being a separate entity from the amniotic fluid as originally described in 1948 by Jost and Policard. [2] I believe this is an important knowledge gap that needs to be addressed. Understanding of metabolism and role of fetal lung fluid in lung development and postnatal transition is essential to clinicians involved in the care of newborns and infants.Though a comprehensive review of fetal lung fluid is beyond the scope of this letter, I provide a brief basic overview of fetal lung fluid with references for more comprehensive reading.Fetal lung fluid is a chloride rich acidic fluid produced with in the fetal lungs by secretion of chloride across the distal lung epithelial cells and is a major determinant for fetal lung growth and development. The fluid lung volume is maintained by transglottic pressure gradient with periodic egress of excess fluid during fetal breathing. Decreased lung fluid volume is associated with pulmonary hypoplasia and conversely, upper airway lesions obstructing the egress of lung fluid leads to increase in fetal lung fluid and volume, a principle used in fetal interventions such as endoluminal tracheal occlusion to enhance pulmonary growth in conditions namely congenital diaphragmatic hernia. [2,3,4]As important the fetal lung fluid is for lung development, clearance of lung fluid is crucial for normal postnatal transition and establishment of air filled lungs for effective gas exchange. Clearance of lung fluid is a complex and coordinated process that starts before the process of birth itself. The rate of lung fluid secretion diminishes before labor at term gestation. Catecholamines namely epinephrine released during labor upregulates the epithelial sodium channels (ENaC) promoting influx of sodium and fluid from lumen into pulmonary interstitial space thereby reversing the direction of fluid movement in the perinatal period. Lung fluid is decreased to about 35% following active labor and birth which are further cleared with neonatal cry and breathing and inflow of air after birth. The fluid from the interstitial space is cleared over the next few hours via pulmonary circulation and lymphatic drainage. However this process is impaired in infants delivered by elective cesarean sections leading to increased retained lung fluid after birth and resulting in transient respiratory distress and tachypnea of newborn (TTN). In preterm infants, catecholamine induced fluid reabsorption via ENaC is limited and may contribute to respiratory distress after birth. Prenatal maternal steroids and triiodothyronine administration is known to induce expression of messenger RNA for ENaC subunits in the fetal lungs and may facilitate lung fluid clearance. [2,4]Lastly, amniotic fluid aspiration into fetal lungs, with and without meconium contamination, has been reported to be the cause of respiratory distress with case reports of massive amniotic fluid aspiration noted on postmortem histological examination of newborn lungs. [5]References:Rocha G. Pulmonary pneumatoceles in neonates. Pediatr Pulmonol. 2020 Jul 21. doi: 10.1002/ppul.24969. Epub ahead of print. PMID: 32691976.Katz C, Bentur L, Elias N. Clinical implication of lung fluid balance in the perinatal period. J Perinatol. 2011 Apr;31(4):230-5. doi: 10.1038/jp.2010.134. PMID: 21448181.Hooper SB, Harding R. Fetal lung liquid: a major determinant of the growth and functional development of the fetal lung. Clin Exp Pharmacol Physiol. 1995 Apr;22(4):235-47. doi: 10.1111/j.1440-1681.1995.tb01988.x. PMID: 7671435Kallapur S, Jobe A; Fetal Lung fluid. Richard J. Martin, Avroy A. Fanaroff, Michele C. Walsh. Fanaroff And Martin’s Neonatal-Perinatal Medicine : Diseases of the Fetus and Infant, 10th edition. Philadelphia, PA :Elsevier/Saunders, 2015Lavezzi AM, Poloniato A, Rovelli R, Lorioli L, Iasi GA, Pusiol T et al. Massive Amniotic Fluid Aspiration in a Case of Sudden Neonatal Death With Severe Hypoplasia of the Retrotrapezoid/Parafacial Respiratory Group. Front Pediatr. 2019 Apr 4;7:116. doi: 10.3389/fped.2019.00116. PMID: 31019904
EDITORIAL: The Many Challenges to the Field of Pediatric Pulmonology Posed by Pediatr...
George Mallory
Steven Abman

George Mallory

and 1 more

December 12, 2020
Pulmonary hypertension represents an increasingly important group of pediatric patients which commonly come to the attention, if not the primary care of pediatric pulmonologists around the world. There have been major advances in diagnosis and therapy over the past 25 years. To address potential gaps in knowledge, the authors were invited by the Editor of Pediatric Pulmonology to organize a series of manuscripts in a special supplement of the journal. Our authors include pulmonologists, pharmacists, intensivists, mid-level practitioners, neonatologists and cardiologists. We believe that this issue will be of great interest to most of the readership community that the Journal addresses.
Pediatric Tricuspid Valve Infective Endocarditis- Insite into a challenging managemen...
Amitabh Satsangi
DHARAMRAJ SINGH

Amitabh Satsangi

and 1 more

December 12, 2020
:Pediatric tricuspid vavle endocarditis is an uncommon entity which is now becoming prevalent oweing to improved diagnostic methods and increase number of cardiac surgeries.Paediatric right sided infective endocarditis are mostly secondary to structural heart defects or indwelling venous catheters .We present a case of paeditric tricuspid valve endocarditis presenting with complete heart block,septic arthritis, pulmonary abcess with no structural heart defect diagnosted preoperatively.Intra-operatively a ventricular septal defect was diagnosed and managed .We present the difficult management of the case by medical and surgical intervention and management of secondary fungal infective endocarditis with repeated successful surgical intervention . We also emphasize on lack of established guidelines for management of right -sided infective endocarditis.
Coronavirus antibody screening identifies children with mild to moderate courses of P...
Otto  Laub
Georg Leipold

Otto Laub

and 20 more

December 12, 2020
Background: Children are affected rather mildly by the acute phase of COVID-19, but predominantly in children and youths, the potentially severe and life threatening pediatric multiorgan immune syndrome (PMIS) occurs later on. To identify children at risk early on, we searched for antibodies against SARS-CoV-2 and searched for early and mild symptoms of PMIS in those with high levels of antibodies. Methods: In a cross-sectional design, children aged 1-17 were recruited through primary care pediatricians for the study (a), if they had an appointment for a regular health check-up or (b), or if parents and children volunteered to participate in the study. Two antibody tests were performed in parallel and children with antibody levels >97th percentile (in the commercially available test) were screened for signs and symptoms of PMIS and SARS-CoV-2 neutralization tests were performed. Results: We identified antibodies against SARS-CoV-2 in 162 of 2832 eligible children (5.7%) between June and July 2020 in three, in part strongly affected regions of Bavaria. Approximately 60% of antibody positive children showed high levels of antibodies. In those who participated in the follow up screening, 30% showed some mild and minor symptoms similar to Kawasaki disease and in three children, cardiac and neuropsychological symptoms were identified. Symptoms correlated with high levels of non-neutralizing and concomitantly low levels of neutralizing antibodies and lower neutralizing capacity. Conclusions: Children exposed to SARS-CoV-2 should be screened for antibodies and those children with positive antibody responses should undergo a stepwise assessment for late COVID-19 effects.
Irrigation water quality may improve in arid regions of China
Guofeng Zhu
Huiying Ma

Guofeng Zhu

and 6 more

December 12, 2020
The stability and safety of water environment are the foundation of agricultural development. The possibility of salinization and desertification in the oasis agricultural area is much higher than that in other areas, for the population density, lack of water resources and high salinity. Therefore, it is necessary to study the water environment of irrigation water in this area, so as to make a reasonable water resource utilization and protection plan. In the agricultural irrigation period (from Apr. to Sep.) and non-irrigation period (from Oct. to Mar. of the next year), there were 9 sampling points set up from the source area to the oasis of the middle and lower reaches in Shiyang River Basin. Evaluating the irrigation water quality of surface water by ion concentration, SAR and end-member mixing diagram. The results shown: (1) the dilution effect of precipitation has a decisive influence on the ion concentration of surface water in the watershed. Due to the overlapping of irrigation period and rainy season, rainfall dilution makes irrigation water quality better. (2) There are spatial differences in hydrochemical types. The upstream hydrochemical type is mainly Ca-HCO3 type. The hydrochemical type of the middle and lower reaches is Ca (Na) - HCO3 mixed type. The upstream surface water is very suitable for agricultural irrigation, and the middle and downstream oasis area is suitable. (3) Surface rock weathering and evaporation crystallization are the main factors affecting the hydrochemical characteristics of surface water. Due to changes in the underlying surface environment in a short time, it is unlikely that the water quality will deteriorate. (4) In recent years, with the increase in precipitation caused by climate change and the strict environmental protection policies, the risk of deterioration of irrigation water quality is greatly reduced, surface water may be more suitable for agricultural irrigation.
Modeling the Hydrological Characteristics of Hangar Watershed, Ethiopia
Abdata Galata

Abdata Galata

December 12, 2020
Modelling the hydrological characteristics of watershed is a method of understanding behavior and simulating the water balance components of watershed for planning and development of integrated water resources management. The soil and water assessment tool (SWAT) physically based hydrological modelling was used for modelling hydrologic characteristics of the Hangar watershed. The data used for this study were digital elevation model (DEM), land use land cover data, soil map, climatological and hydrological data. The model calibrated and validated using measured streamflow data of 13 years (1990-2002) and 9 years (2003-2011) respectively including warm-up period. The SWAT model performs well for both calibration (R2 = 0.87, NSE = 0.82 and PBIAS = +1.4) and validation (R2 = 0.89, NSE = 0.88 and PBIAS = +1.2). The sensitivity analysis, which was carried out using 18 SWAT parameters, identified the 13 most sensitive parameters controlling the output variable and with which goodness-of-fit was reached. The analysis results indicated that the watershed receives around, 9.6%, 59.9%, and 30.5% precipitation during dry, wet and short rainy seasons respectively. The received precipitation was lost by 9.6 %, 40.5%, and 41.3% in the form of evapotranspiration for each seasons correspondingly. The surface runoff contribution to the Watershed were 3.8%, and 79.2% during dry and wet seasons respectively, whereas, it contributes by 17.0% during short rainy seasons.
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