Assessing the gas sensing capability of undoped and doped aluminum nitride nanotubes.

CONTEXT: CO2 and CO gas sensors are very important to recognize the insulation situation of electrical tools. ToCO explore the application of noble metal doped of aluminum nitride nanotubes for gas sensors, DFT computations according to the first principal theory were applied to study sensitivity, adsorption attributes, and electronic manner. In this investigation, platinum-doped aluminum nitride nanotubes were offered for the first time to analyze the adsorption towards CO2 and CO gases. Firm construction of platinum-doped aluminum nitride nanotubes (Pt-AlNNT) was investigated in four feasible places, and the binding energy of firm construction is 1.314 eV. Respectively, the adsorption energy between the CO2 and Pt-AlNNT systems was - 2.107 eV, while for instance of CO, the adsorption energy was - 3.258 eV. The mentioned analysis and computations are considerable for studying Pt-AlNNT as a new CO2 and CO gas sensor for electrical tools insulation. The current study revealed that the Pt-AlNNT possesses high selectivity and sensitivity towards CO2 and CO. METHODS: In this research, Pt-doped AlNNT (Pt-AlNNT) has been studied as sensing materials of CO and CO2 for the first time. The adsorption process of Pt-AlNNT has been computed and analyzed through the DFT approach. DFT computations by using B3LYP functional and 6-31 + G* basis sets have been applied in the GAMESS code for sensing attributes, which contribute to potential applications.

Retraction: Saddle Aortic Embolism Following Recovery From Severe COVID-19 Pneumonia.

[This retracts the article DOI: 10.7759/cureus.18074.].

Kikuchi-Fujimoto Disease Following COVID-19.

Kikuchi-Fujimoto Disease (KFD) is a rare self-limiting condition of unknown etiology. It is characterized by fever, and lymphadenopathy most commonly involving posterior cervical lymph nodes. Although it is of uncertain etiology, it is associated with viral infections and autoimmune diseases. Distinction from lymphadenopathy-associated alternate disorders is crucial to avoid unneeded diagnostic procedures and treatment. KFD is diagnosed based on histopathologic examination of the excised lymph node. The management is supportive with favorable outcomes within a few weeks or months. In this case, we describe a 13-year-old boy who complained of painful cervical lymphadenopathy and fever for more than three weeks following COVID-19. Diagnostic workup has been established and KFD diagnosis made based on the histopathologic features of the involved lymph node. The patient showed complete recovery with no recurrence during follow-up. So, this case highlights the possible association between COVID-19 and KFD during this pandemic and keeping it in the differential diagnosis.

Saddle Aortic Embolism Following Recovery From Severe COVID-19 Pneumonia.

Coronavirus disease 2019 (COVID-19) is a multi-organ disease with a wide range of manifestations. Coagulopathy is one of the well-recognized complications of COVID-19. We report the case of a 42-year-old man who presented with progressively worsening low back pain of two days in duration. The pain was burning in character, non-radiating, and was not related to movement. The patient had a recent history of severe COVID-19 pneumonia requiring mechanical ventilation and has stayed in the intensive care unit for eight days. He was discharged three days before the acute onset of his back pain. Examination of the lumbar spine was unremarkable. However, lower limb examination revealed coldness and absent pulses bilaterally. The patient underwent computed tomography angiography which revealed complete occlusion of the lower abdominal aorta at its bifurcation. Emergency endovascular treatment was performed to aspirate the clot. The symptoms resolved following the procedure and the patient was discharged on the third post-intervention day. Saddle aortic embolism is a rare life-threatening condition that may present solely with low back pain. The case demonstrated a possible complication of COVID-19 that occurred after the recovery from the acute phase of the disease.

Parenteral versus enteral nutrition in children with post-surgical congenital heart disease.

OBJECTIVE: The association of malnutrition with congenital heart disease (CHD) is well documented. Studies comparing the effects of parenteral nutrition (PN) and enteral feeding (EF) on the post-surgical correction of CHD are not available. We compared the effects of PN with EF on the nutritional status of children post-cardiac surgery. METHODS: A retrospective cohort study was conducted with 72 children aged ≤6 years who had at least one heart surgery between 2010 and 2016. Malnutrition was defined as a weight for height Z-score (WHZ) below -2. The primary endpoint was the change in the mean WHZ Z-score from the baseline. All statistical analyses were performed using SPSS 21.0 [Release 21.0.0.0, IBM, USA]. RESULTS: The sample size realized as 72 (n = 72). The overall prevalence of malnutrition was 48%. The change in height of the PN group was significantly higher than the EF group (14.2 ± 7.6 cm vs. 7.4 ± 6.3, P = 0.010), but the weight change was not significantly different (P = 0.28). The post-surgery Z-scores were significantly lower in the PN group and the Z-score change was marginally smaller (P = 0.086), indicating lower growth levels post-surgery. The PN group had a significantly higher incidence of post-surgical malnutrition (P = 0.046). Patients who received PN had significantly less improvement (more negative change) in the Z-score levels compared to the EF group (PE = -1.42, 95% confidence interval [CI] = [-2.48, -0.35]; P = 0.011). CONCLUSION: Malnutrition occurs frequently with CHD. PN does not add any nutritional benefits compared with EF. EF should always be the preferred method of nutrition unless contraindicated.

The prevalence of complications of pneumonia among adults admitted to a tertiary care center in Riyadh from 2010-2017.

BACKGROUND: Pneumonia, the commonest lower respiratory tract infection, can result in respiratory and non-respiratory complications. Few studies have reported on the prevalence of many complications. OBJECTIVES: Identify the prevalence of 18 complications of pneumonia and compare complication rates by age group and type of pneu.monia. Identify most prevalent comorbidities, the effect of the number of comorbidities on the presence of complications, and the association between specific comorbidities and specific complications. DESIGN: Retrospective, cross-sectional prevalence study. SETTING: Tertiary care center in Riyadh. PATIENTS AND METHODS: The target population were patients aged 17 years and older, of different nationalities and both genders, diagnosed with pneumonia during the period of 2010 to 2017. Selection was by stratified sampling by year of admission. MAIN OUTCOME MEASURES: Complications of pneumonia. SAMPLE SIZE: 800. RESULTS: Complications were observed in 427 patients (53.4%). The complications were respiratory in 258 patients (32%), sepsis and septic shock in 186 (23%), cardiac in 125 (16%), neurological in 5 (0.6%), and cholestatic jaundice in 2 (0.3%). Pleural effusion was the commonest complication, observed in 230 patients. There was a significant difference (P less than .001) between the complication rates in older patients compared to younger (60% as compared to 41%). For the type of pneumonia, there was a significant difference (P less than .001) between community-acquired pneumonia and hospital-acquired pneumonia in the presence of complications (OR=2.41, 95% CI for OR=1.66, 3.49). The number of comorbidities was significantly associated with the presence of complications (P=.001) for those with multiple comorbidities (46% for patients with no comorbid illnesses versus 68% in patients with three or more comorbidities). CONCLUSION: These results suggest that Saudi Arabia needs to establish better prevention and intervention programs, especially for the high-risk groups identified in this study: older patients, patients with hospital-acquired pneumonia and patients with two or more comorbidities. LIMITATIONS: Retrospective design and single-centered. CONFLICT OF INTEREST: None.

Pleiotropic effects of cancer cells' secreted factors on human stromal (mesenchymal) stem cells.

INTRODUCTION: Studying cancer tumors' microenvironment may reveal a novel role in driving cancer progression and metastasis. The biological interaction between stromal (mesenchymal) stem cells (MSCs) and cancer cells remains incompletely understood. Herein, we investigated the effects of tumor cells' secreted factors as represented by a panel of human cancer cell lines (breast (MCF7 and MDA-MB-231); prostate (PC-3); lung (NCI-H522); colon (HT-29) and head & neck (FaDu)) on the biological characteristics of MSCs. METHODS: Morphological changes were assessed using fluorescence microscopy. Changes in gene expression were assessed using Agilent microarray and qRT-PCR. GeneSpring 12.1 and DAVID tools were used for bioinformatic and signaling pathway analyses. Cell migration was assessed using a transwell migration system. SB-431542, PF-573228 and PD98059 were used to inhibit transforming growth factor ß (TGFß), focal adhesion kinase (FAK), and mitogen activated protein kinase kinase (MAPKK) pathways, respectively. Interleukin-1ß (IL1ß) was measured using ELISA. RESULTS: MSCs exposed to secreted factors present in conditioned media (CM) from FaDu, MDA-MB-231, PC-3 and NCI-H522, but not from MCF7 and HT-29, developed an elongated, spindle-shaped morphology with bipolar processes. In association with phenotypic changes, genome-wide gene expression and bioinformatics analysis revealed an enhanced pro-inflammatory response of those MSCs. Pharmacological inhibitions of FAK and MAPKK severely impaired the pro-inflammatory response of MSCs to tumor CM (approximately 80% to 99%, and 55% to 88% inhibition, respectively), while inhibition of the TGFß pathway was found to promote the pro-inflammatory response (approximately 3-fold increase). In addition, bioinformatics and pathway analysis of gene expression data from tumor cell lines combined with experimental validation revealed tumor-derived IL1ß as one mediator of the pro-inflammatory phenotype observed in MSCs exposed to tumor CM. CONCLUSIONS: Our data revealed tumor-derived IL1ß as one mediator of the pro-inflammatory response in MSCs exposed to tumor CM, which was found to be positively regulated by FAK and MAPK signaling and negatively regulated by TGFß signaling. Thus, our data support a model where MSCs could promote cancer progression through becoming pro-inflammatory cells within the cancer stroma.