Non-analgesic benefits of combined thoracic epidural analgesia with general anesthesia in on-pump pediatric cardiac surgery: A prospective observational study.

Background: The use of thoracic epidural analgesia in infants and children could attenuate the stress response and thereby improve the outcomes associated with cardiac surgery. Methods: This study is a prospective observational study conducted on 118 patients admitted for cardiac surgery. All patients received thoracic epidural analgesia. Laboratory investigations including inflammatory markers, markers for different organ functions, and intensive care unit parameters were collected at different time points (preoperative, immediate postoperative, on day 1, and day 2). Results: Inflammatory markers such as IL6, IL8, and metabolic response as measured by serum cortisol and blood sugar were significantly high in the immediate postoperative period, which later stabilized in the next 48 h. There was also a sharp increase in the anti-inflammatory marker IL-10 in an immediate postoperative period, which settled later on but continued to be higher than baseline in the next 48 h. All these markers showed lower values when compared to published literature. The baseline renal oxygen saturation using near infrared spectroscopy (NIRS) value in our study was 59.3 + 19, which increased to 76.4 + 12.7 on day 2. Serum neutrophil gelatinase associated lipocalin (NGAL) remained well below normal levels in the perioperative period. PF (pO2/FiO2) ratio and pO2 consistently improved postoperatively with the maximum on day 2. The median mechanical ventilation (MV) duration was 18 h, and the mean length of stay that included intensive care unit stay was 12 days. No epidural-related adverse events were noted. Conclusions: Apart from good analgesia, patients receiving thoracic epidural analgesia displayed a reduction in perioperative stress, superior postoperative glycemic control, reduction in inflammatory markers, postoperative acute kidney injury, and pulmonary complications.

YouTube as a Patient Information Source for Tendon Repair Surgery.

Background For tendon rupture, a disabling musculoskeletal injury, surgical management is considered the gold standard. The goal is to reduce complications and enable the patient to regain full mobility and strength. With the rise of modern internet accessibility and social media, YouTube has become a frequently used platform for all ages; however, the accuracy and reliability of the videos and the information therein may be a point of concern. Methodology This cross-sectional, observational study was designed to analyze tendon repair surgery information available on YouTube. Data were collected using a Google Forms questionnaire which included questions analyzing the videos and their content and the professional status of the uploaders. Quality and reliability scores were assessed through the Global Quality Score (GQS), reliability score, and Video Power Index (VPI). Statistical analysis was performed using SPSS software (IBM Corp., Armonk, NY, USA). We included videos one minute to twenty minutes in length that were relevant to the topic of tendon repair surgery and in the English language. Results A total of 82 videos were evaluated, of which 67 videos were chosen. A comparison of GQS, reliability score, and VPI based on the type of uploader was done using the Kruskal-Wallis test. The association between GQS and reliability score with that of the video uploader was found to be statistically significant (p < 0.05). Videos uploaded by hospitals had the highest GQS (4) and reliability score (4). Conclusions On comparing the uploader type, videos uploaded by hospitals had good quality and were useful for patients. The quality and reliability of the videos were almost above average. Only half discussed the signs and symptoms and even fewer discussed pre- and post-procedural care. The most important aspect, i.e., prevention, was mentioned in none of the videos. Due to our limitations, expanding the number of accounts used for search and increasing the number of videos might overcome the search algorithm.

Upper cervical intramedullary schwannoma of the spinal cord presenting with myelopathy: illustrative case.

BACKGROUND: Intramedullary schwannomas account for 1.1% of all spinal schwannomas. Preoperative diagnosis is best accomplished by thoroughly evaluating clinical and radiological characteristics, accompanied by a high index of suspicion. The authors report a case of C2-3 intramedullary schwannoma in a young male who presented with neck pain and vertigo. The current literature is also reviewed. OBSERVATIONS: The authors reviewed the data of a young male with a 2-month history of neck pain and vertigo. Magnetic resonance imaging of the brain and cervical spine showed an intramedullary mass at C2-3 with a syrinx extending into the cervicomedullary junction. Laminectomy, myelotomy, and microsurgical excision of the mass under intraoperative neurological monitoring (IONM) were done. Postoperative pathology reported the specimen as a schwannoma. LESSONS: Gross-total resection of a schwannoma using IONM is the treatment of choice because of the lesion's benign nature, a better prognosis, and defined cleavage plane. Schwannomas should be included in the differential diagnosis of intramedullary spinal tumors. Because of its progressive nature, early surgery is recommended in symptomatic patients.

Zeptoliter DNA Origami Reactor to Reveal Cosolute Effects on Nanoconfined G-Quadruplexes.

Cellular environments such as nanoconfinement and molecular crowding can change biomolecular properties. However, in nanoconfinement, it is extremely challenging to investigate effects of crowding cosolutes on macromolecules. By using optical tweezers, here, we elucidated the effects of hexaethylene glycol (HEG) on the mechanical stability of a telomeric G-quadruplex (GQ) in a zeptoliter DNA origami reactor (zepto-reactor). When HEG molecules were introduced in the GQ-containing zepto-reactor at different positions, we found that the GQ species split into two equilibrated populations, reflecting diverse effects of the oligoethylene glycol on the GQ via either a long-range dehydration effect or direct interactions. When the number of HEG molecules was increased, the stability of the GQ unexpectedly decreased, suggesting that the direct destabilizing interaction between the GQ and HEG is dominating over the long-range stabilizing dehydration effects of the HEG in hydrophilic nanocavities. These findings indicate that a nanoconfined environment can alter regular effects of cosolutes on biomacromolecules.

An informatics approach to distinguish RNA modifications in nanopore direct RNA sequencing.

Modifications in RNA can influence their structure, function, and stability and play essential roles in gene expression and regulation. Methods to detect RNA modifications rely on biophysical techniques such as chromatography or mass spectrometry, which are low throughput, or on high throughput short-read sequencing techniques based on selectively reactive chemical probes. Recent studies have utilized nanopore-based fourth-generation sequencing methods to detect modifications by directly sequencing RNA in its native state. However, these approaches are based on modification-associated mismatch errors that are liable to be confounded by SNPs. Also, there is a need to generate matched knockout controls for reference, which is laborious. In this work, we introduce an internal comparison strategy termed "IndoC," where features such as 'trace' and 'current signal intensity' of potentially modified sites are compared to similar sequence contexts on the same RNA molecule within the sample, alleviating the need for matched knockout controls. We first show that in an IVT model, 'trace' is able to distinguish between artificially generated SNPs and true pseudouridine (Ψ) modifications, both of which display highly similar mismatch profiles. We then apply IndoC on yeast and human ribosomal RNA to demonstrate that previously reported Ψ sites show marked changes in their trace and signal intensity profiles compared with their unmodified counterparts in the same dataset. Finally, we perform direct RNA sequencing of RNA containing Ψ intact with a chemical probe adduct (N-cyclohexyl-N'-ß-(4-methylmorpholinium) ethylcarbodiimide [CMC]) and show that CMC reactivity also induces changes in trace and signal intensity distributions in a Ψ specific manner, allowing their separation from high mismatch sites that display SNP-like behavior.

High-resolution imaging and fast number estimation of suspended particles using dewetted polymer microlenses in a microfluidic channel.

We have fabricated polymer micro-lens array by self-organized dewetting inside the microchannel, which shows remarkable enhancement in the resolution, contrast and more than 10 times add-on magnification to a microscope. These lenses are demonstrated to resolve sub-micrometer features and detect moving micro-particles when suspension is flown in a microchannel. Polystyrene (PS) micro-lenses are fabricated on a polydimethylsiloxane (PDMS) substrate using the controlled dewetting of PS thin film then this PDMS substrate is used to close the microchannel with inverted micro-lenses on it. An aqueous suspension of polystyrene particles is flown through the microchannel and we have observed the particles through an optical microscope. Focusing and magnification through PS micro-lenses is analyzed to get a quantitative estimate of the particle number density in the solution. This method offers a promising low-cost high throughput solution for determining the approximate number density of flowing particles or suitably stained biological cells. Particularly in a pathology lab it can tremendously increase detection limit by enabling visibility of sub-micrometer pathogens using a standard laboratory microscope.

Photocontrolled DNA Origami Assembly by Using Two Photoswitches.

Stimuli-responsive switching molecules have been widely investigated for the purpose of the mechanical control of biomolecules. Recently developed arylazopyrazole (AAP) shows photoisomerization activity, displaying a faster response to light-induced conformational changes and unique absorption spectral properties compared with those of conventionally used azobenzene. Herein, it is demonstrated that AAP can be used as a photoswitching molecule to control photoinduced assembly and disassembly of DNA origami nanostructures. An AAP-modified DNA origami has been designed and constructed. It is observed that the repeated assembly and disassembly of AAP-modified X-shaped DNA origami and hexagonal origami with complementary strands can be achieved by alternating UV and visible-light irradiation. Closed and linear assemblies of AAP-modified X-shaped origami were successfully formed by photoirradiation, and more than 1 µm linear assemblies were formed. Finally, it is shown that the two photoswitches, AAP and azobenzene, can be used in tandem to independently control different assembly configurations by using different irradiation wavelengths. AAP can extend the variety of available wavelengths of photoswitches and stably result in the assembly and disassembly of various DNA origami nanostructures.

Duplex DNA Is Weakened in Nanoconfinement.

For proteins and DNA secondary structures such as G-quadruplexes and i-motifs, nanoconfinement can facilitate their folding and increase structural stabilities. However, the properties of the physiologically prevalent B-DNA duplex have not been elucidated inside the nanocavity. Using a 17-bp DNA duplex in the form of a hairpin stem, here, we probed folding and unfolding transitions of the hairpin DNA duplex inside a DNA origami nanocavity. Compared to the free solution, the DNA hairpin inside the nanocage with a 15 × 15 nm cross section showed a drastic decrease in mechanical (20 → 9 pN) and thermodynamic (25 → 6 kcal/mol) stabilities. Free energy profiles revealed that the activation energy of unzipping the hairpin DNA duplex decreased dramatically (28 → 8 kcal/mol), whereas the transition state moved closer to the unfolded state inside the nanocage. All of these indicate that nanoconfinement weakens the stability of the hairpin DNA duplex to an unexpected extent. In a DNA hairpin made of a stem that contains complementary telomeric G-quadruplex (GQ) and i-motif (iM) forming sequences, formation of the Hoogsteen base pairs underlining the GQ or iM is preferred over the Watson-Crick base pairs in the DNA hairpin. These results shed light on the behavior of DNA in nanochannels, nanopores, or nanopockets of various natural or synthetic machineries. It also elucidates an alternative pathway to populate noncanonical DNA over B-DNA in the cellular environment where the nanocavity is abundant.

Advances in DNA Origami-Cell Interfaces.

The nascent field of DNA nanotechnology has undergone rapid growth since its inception. By using DNA as a biologically "safe" material, DNA nanotechnology shows great promise in applications such as drug-delivery systems. Further progress, however, relies on understanding the different ways in which DNA nanostructures behave in and interact with cells, tissues and even whole organisms. Moreover, this knowledge must then be harnessed in innovative ways to improve existing DNA nanostructures and design new ones, so that they can perform more diverse functions more effectively. There have been many developments in this regard in the past few years, and herein some of these are highlighted, with respect to both works that improve our understanding of what happens to DNA nanostructures once they are at their target site, and those that utilise clever design to accomplish desired functions.

Fractionation and characterization of lignin from waste rice straw: Biomass surface chemical composition analysis.

Waste rice straw (RS) was fractionated to extract the lignin using alkaline (sodium hydroxide) treatment (SHT) and organic acid (Formic acid/Acetic acid) treatment (OAT) process. Rice straw fractionation by the acetic OAT and alkaline SHT methods resulted in the recovery of OAT-lignin and SHT-lignin respectively. The structural characterization of the extracted lignin fractions was done by UV-vis spectroscopy, FTIR and 1H NMR technique. Total phenolic content (TPC) present in SHT-lignin and OAT-lignin were determined to be 28.87 mg GAE/g and 24.75 mg GAE/g respectively. The DPPH radical scavenging activity 59.50% was observed in SHT-lignin and 45.74% in OAT-lignin using the DPPH test for 30 min of incubation. Surface characterization of untreated rice straw (UT-RS) and treated rice straw (SHT-RS and OAT-RS) were carried out by XRD, FTIR and SEM. X-ray photoelectron spectroscopy (XPS) survey, C1s, and O1s spectra were used to determined the surface carbon and oxygen composition changes in RS after SHT and OAT. These structural characterizations of lignin and biomass are beneficial for further processing in bio-refinery industry.

Corn husk derived magnetized activated carbon for the removal of phenol and para-nitrophenol from aqueous solution: Interaction mechanism, insights on adsorbent characteristics, and isothermal, kinetic and thermodynamic properties.

In this study, waste corn husk was used for the synthesis of an effective adsorbent (cornhusk activated carbon, CHAC) and by treating at two different temperatures, 250 °C (CHAC-250) and 500 °C (CHAC-500) to check adsorption efficiency. The synthesized adsorbents were characterized with the help of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy, Particle size analysis and x-ray diffraction (XRD), which revealed the different properties of the two adsorbents. The synthesized adsorbents were applied for the removal of phenol and p-nitrophenol (PNP) from aqueous solution. CHAC-500 was more efficient than the CHAC-250. The maximum adsorptions of phenol and PNP by CHAC-500 were ∼96% and ∼94%, respectively, while the maximum adsorptions of phenol and PNP by CHAC-250 were ∼81% and ∼84%, respectively. The adsorption processes were best fitted with the Langmuir adsorption isotherm and the pseudo-second-order kinetic model. The adsorption of phenol was an exothermic process, while that of PNP was an endothermic process, on both adsorbents.