Additional Stability Research Articles

Comparison of the forearm rotation restriction capacities of four upper-extremity immobilization methods: there is no difference between single and double sugar tong splinting

BackgroundThe aim of this study was to compare the effects of four different immobilization methods [single sugar tong splint (SSTS), double sugar tong splint (DSTS), short arm cast (SAC), and long arm cast (LAC)] commonly used for restricting forearm rotation in the upper extremity.MethodsForty healthy volunteers were included in the study. Dominant extremities were used for measurements. Basal pronation and supination of the forearm were measured with a custom-made goniometer, and the total rotation arc was calculated without any immobilization. Next, the measurements were repeated with the SAC, LAC, SSTS and DSTS. Each measurement was compared to the baseline value, and the percentage of rotation restriction was calculated.ResultsThe most superior restriction rates were observed for the LAC (p = 0.00). No statistically significant difference was detected between the SSTS and DSTS in terms of the restriction of supination, pronation or the rotation arc (p values, 1.00, 0.18, and 0.50, respectively). Statistically significant differences were not detected between the SAC and the SSTS in any of the three parameters (p values, 0.25; 1.00; 1.00, respectively). When the SAC and DSTS were compared, while there was no significant difference between the two methods in pronation (p = 0.50), a statistically significant difference was detected in supination (p = 0.01) and in the total rotation arc (p = 0.03).ConclusionThe LAC provides superior results in restricting forearm rotation. The SAC and SSTS had similar effects on forearm rotation. The DSTS, which contains, in addition to the SSTS, a sugar tong portion above the elbow, does not provide additional rotational stability.

A new configuration of lateral-pin fixation for pediatric supracondylar humeral fracture: A biomechanical analysis.

The aim of this study was to biomechanically compare a new lateral-pinning technique, in which pins engage the medial and lateral columns of the distal humerus in a divergent configuration in both the axial and sagittal planes instead of the coronal plane, with the cross-pin, and with 2 and 3 coronally divergent lateral-pin techniques in a synthetic humerus model of supracondylar humerus fractures. Thirty-six identical synthetic models of the humerus simulating a standardized supracondylar humerus fracture were included in this study. They were divided into 4 groups based on the pin configuration of fixation: the new 3-lateral pin-fixation technique (group A), 2 crossed pins (group B), 3 divergent lateral pins (group C), and 2 divergent lateral pins (group D). Each model was subjected to combined axial and torsional loading, and then torsional stability and torsional stiffness (Nmm/°) were recorded. Group A had greater rotational stability than groups C and D but had no statistically significant additional rotational stability compared with group B (P=.042, P=.008, P=.648, respectively), whereas group B had greater rotational stability than only group D (P=.020). Furthermore, group A demonstrated higher internal rotational stiffness compared with groups C and D (P=.038, P=.006, respectively). Group B had better internal rotational stiffness than group D (P=.015). There was no significant difference in internal rotational stiffness between groups A and B (P=. 542), groups B and C (P=.804), and groups D and C (P=.352). Although no statistically significant differences existed between groups A and B, the modified pin configuration exhibited the highest torsional stability and stiffness. Group D showed the lowest values in all biomechanical properties. This study has shown us that this new lateral-pinning technique may provide torsional resistance to internal rotational displacement as strong as the standard technique of crossed-pin configuration of fixation. Furthermore, with this new pin configuration, greater torsional resistance can be obtained than with either the standard 2- or the standard 3-lateral divergent pin configuration. Cite this article as: Bilgili F, Demirel M, Birişik F, Balcı Hİ, Sunbuloglu E, Bozdag E. A new configuration of lateral-pin fixation for pediatric supracondylar humeral fracture: A biomechanical analysis. Acta Orthop Traumatol Turc., 2023 10.5152/j.aott.2024.21091 [Epub Ahead of Print].

MB16 - (M=Sc, Y, La): Perfect Bowl-Like Boron Clusters.

The introduction of transition-metal doping has engendered a remarkable array of unprecedented boron motifs characterized by distinctive geometries and bonding, particularly those heretofore unobserved in pure boron clusters. In this study, we present a perfect (no defects) boron framework manifesting an inherently high-symmetry, bowl-like architecture, denoted as MB16 - (M=Sc, Y, La). In MB16 -, the B16 is coordinated to M atoms along the C5v-symmetry axis. The bowl-shaped MB16 - structure is predicted to be the lowest-energy structure with superior stability, owing to its concentric (2 π+10 π) dual π aromaticity. Notably, the C5v-symmetry bowl-like B16 - is profoundly stabilized through the doping of an M atom, facilitated by strong d-pπ interactions between M and boron motifs, in conjunction with additional electrostatic stabilization by an electron transfer from M to the boron motifs. This concerted interplay of covalent and electrostatic interactions between M and bowl-like B16 renders MB16 - a species of exceptional thermodynamic stability, thus making it a viable candidate for gas-phase experimental detection.

Dispersion stability analysis of vegetable oil-based ionanolubricants

Recently, environmentally acceptable lubricants (EALs) developed from vegetable oils are more widely used in the field of lubrication technology as an alternative to mineral and synthetic oils. The homogeneous and long-term stability of additives in base lubricants is a crucial requirement for potential applications of vegetable oil-based ionanolubricants (INLs). In this study, the INLs have been formulated with two vegetable oils, rice bran oil and sesame oil containing TiO2 nanoparticles (NPs) and two ionic liquids IL1, 1-ethyl 3-methylimidazolium dicyanamide [EMIM][DCN] and IL2, trihexyltetradecylphosphonium bis(24,4-trimethylpentyl) phosphinate ([P66614][BTMPP]) with surfactants. The main objective is to find the suitable surfactant among sodium dodecyl sulfate (SDS), Tween 20 (T-20), and Triton X-100 (TX-100) and its optimum additives to surfactant ratio. Dispersion stability of INLs has been investigated by using visual monitoring and dynamic light scattering. The analysis showed that additives start agglomeration and make larger clusters on the 10th and 20th days of formulation, respectively. On the 30th day of formulation, the larger clusters settle down in the bottom due to gravity. However, in spite of this pattern, the additives remain stable in vegetable oils at particular optimum additives to surfactant ratio. Four stable samples were recorded on the basis of dispersion stability analysis. Rice bran oil and IL1-based INLs having additives to TX-100 of 1:2 have found long-term stability. Additives to SDS ratios of 1:6 was found optimum for rice bran oil and IL2-based INLs. Similarly, for sesame oil-based INLs, the additives to T-20 ratios of 1:4 and 1:2 are found optimum for IL1 and IL2, respectively.

Discoid Meniscus – A Review of Literature and Our Case Series

Abstract Aim: The current study aims at the surgical outcome of the lateral discoid meniscus which is treated with knee arthroscopy, meniscal refashioning, and meniscal repair in various age groups. Materials and Methods: The study includes 7 patients (3 females and 4 males) with a mean age of 26.6 (Range 10 to 50 years). This is a retrospective type of study with a study period ranging from June 2018 to January 2024. Results: Patient satisfaction was excellent in all cases regarding pain, locking of the knee, Range of motion, and return to sports/daily activities. Diagnostic Arthroscopy confirmed the discoid meniscus abnormality in all the cases. Bucket handle type tear of the lateral menisci in 2 cases. Anterior horn tear in 1 case. Horizontal tear in 1 case. Unstable discoid meniscus in 3 cases. Meniscoplasty, removal of central part of meniscus, and sparing its periphery was done for all cases. Stabilization of the meniscus was done with meniscal repair in 4 patients with inside-out and all inside techniques. Visual analog score (VAS score) has significantly reduced from moderate pain (45-74)and mild pain (5-44 mm)to no pain (0-4 mm). Conclusion: Arthroscopic sauscerization, meniscoplasty alone, or additional stabilization with meniscal repair can provide excellent clinical outcomes in patients with symptomatic lateral discoid meniscus.

Tooth-Supported Overdenture – Preventive Prosthodontics to Redeem Ridge Resorption

Abstract This case series elaborates on tooth-supported overdenture for prosthetic rehabilitation as a treatment modality in partially edentulous patients. Loss of teeth causes continuous ridge resorption and poor denture foundation affecting the success of prosthesis. Retained natural teeth act as abutments for prosthetic rehabilitation of partial edentulous arches. Tooth-supported overdenture is the mainstay of preventive prosthodontics which preserves natural teeth and/or roots. The cases describe the use of tooth-supported complete overdenture and removable partial overdenture with metal denture base to rehabilitate partially edentulous arches. The natural teeth maintain proprioception and provide additional support, stability, retention, and psychological benefit to the patient than the conventional complete denture with completely edentulous ridges.

The Role of the Hip Capsule in Restoring Stability in the Initial Phase of Hip Distraction: An In Vivo Analysis

Background: The labral suction seal has been shown to provide the majority of resistance in the initial phase of hip distraction. However, the effect of an unrepaired interportal capsulotomy and capsular repair on the initial phase of hip distractive stability in vivo is not well understood. Purpose: To investigate the effect of capsular repair on the initial phase of distractive stability of hip joints in patients with femoroacetabular impingement (FAI) syndrome. Study Design: Controlled laboratory study. Methods: Patients undergoing primary hip arthroscopy for FAI between March and August 2020 were prospectively enrolled. Total joint space was measured on fluoroscopic images at the medial and lateral edges of the sourcil at 12.5-lb (5.7-kg) axial traction intervals (up to 100 lb [45.4 kg]) in 3 capsular states: (1) native capsule, (2) interportal capsulotomy, and (3) capsular repair. Distraction on anteroposterior radiographs was calculated as the difference between total joint space at each traction interval and baseline joint space at 0 lb, normalized to millimeters. The native, capsulotomy, and capsular repair states were compared using Wilcoxon signed-rank and McNemar tests. Results: Included were 36 hips in 35 patients. The median force required to distract ≥3 mm was 75 lb (34.0 kg; 95% CI, 70-80 lb [31.8-36.3 kg]) in both the native and capsular repair states ( P = .629), which was significantly greater than the median force required to distract ≥3 mm in the capsulotomy state (50 lb [22.7 kg]; 95% CI, 45-55 lb [20.4-24.9 kg]) ( P < .001). The most rapid rates of change in joint space were observed at the traction interval at which hips first achieved ≥3 mm of distraction (n = 33 hips; 92%). Conclusion: The traction force at which hips distracted ≥3 mm was 75 lb (34.0 kg) in both the native capsular and capsular repair states. Significantly less traction force (50 lb [22.7 kg]) distracted hips ≥3 mm in the capsulotomy state. Complete capsular closure after interportal capsulotomy resulted in restoration of initial distractive stability relative to the unrepaired capsulotomy state at time zero after primary hip arthroscopy. Clinical Relevance: This study provides surgeons with an improved understanding of the additional stability to the hip joint from capsular repair after hip arthroscopy for FAI syndrome.

Marker assisted breeding of Sub1 introgressed rice (Oryza sativa L.) lines and identification of stable variety MTU 1232 suitable for flood prone ecosystem

The Development of flood-tolerant rice varieties is a prerequisite for climate resilience in flood-prone areas. The present study aimed to develop a stable, high, yielding, and tolerant rice variety against flash floods and stagnant flooding across multiple environments. Sub1A was incorporated into a popular rice variety MTU 1075 using Swarna-sub1 as a donor to generate BC3F5 families. Sub1BC2 was used as a foreground marker for selection, a proxy for the Sub1A gene. RM23865 and RM464 on Chromosome 9 were used as recombinant markers. Backcross families from the BC3F2 generation were evaluated under two weeks of flash floods 15 days after transplanting. This was followed by stagnant flooding and survived BC3F4 families were used for background selection using a 50K high-density SNP chip. The nine best families identified were included in the field trial evaluation under eight environments. Consequently, MTU Rice 1232 was identified as a high-yielding, flood-tolerant rice variety using Additive Main effects and Multiplicative Interaction stability analysis. The MTU Rice 1232 ranked first by the Best linear unbiased prediction (BLUP) based ranking parameters and 4th based on stability parameters ranking. This flood-tolerant rice variety can tolerate both flash floods and stagnant flooding and possesses an 80% survival rate. It has a yield potential of 3792 Kg ha-1 under severe floods and 6000 Kg ha-1 under normal conditions.

Thermodynamics and kinetics of interconversion between platinum nanoparticles and cations in zeolites

In metal-containing zeolites, sintering and redispersion processes exercise control over the identity of metal site structures, but the thermodynamic and kinetic factors that influence these molecular-level processes are not completely understood. Here, we assess the ability of first principles informed free energy models (for supported and unsupported nanoparticles) and kinetic models integrating Ostwald ripening with atom trapping to describe the interconversion between Pt cations and nanoparticles encapsulated in chabazite (CHA) zeolites. Density functional theory-derived thermodynamic phase diagrams show that the interconversion between cations, favored in oxidizing environments, and particles, favored in reducing environments, is fully reversible within a wide range of their respective conditions (temperatures and pressures) for CHA and several other zeolite topologies. Kinetic Monte Carlo simulations of Pt redispersion are consistent with experimentally observed redispersion kinetics of encapsulated Pt nanoparticles in CHA zeolites, and model results suggest the zeolite host imparts additional stability for Pt nanoparticles. We envision our thermodynamic and kinetic models for Pt-CHA are also capable of describing nanoparticle and cation interconversions for other zeolite frameworks under similar conditions.

Three-dimensional variable center of mass height biped walking using a new model and nonlinear model predictive control

This paper presents a trajectory generation algorithm for a three-dimensional (3D) biped robot that can adjust the center of mass (CoM) according to the environment. We adopt a new abstract model that supports vertical motion and rotation. Differing from traditional abstract models, the proposed full centroid dynamics inverted pendulum model fully considers the robot’s movement and rotation. Unlike the zero moment point (ZMP), which only ensures the feet do not flip over, we also propose a new additional stability criterion, named zero frictional moment point (ZFMP), guaranteeing no yaw rotation while walking. Next, a nonlinear model predictive control is designed to generate the CoM trajectory, torso rotational angle, and adaptive footholds to induce various biped gaits. A full-dynamics 3D humanoid robot is simulated to test the proposed method while steering, walking underneath a low door, and walking with disturbances.

Elucidation of the Pyridine Ring-Opening Mechanism of 2,2'-Bipyridine or 1,10-Phenanthroline Ligands at Re(I) Carbonyl Complexes.

The cleavage of the C-N bonds of aromatic heterocycles, such as pyridines or quinolines, is a crucial step in the hydrodenitrogenation (HDN) industrial processes of fuels in order to minimize the emission of nitrogen oxides into the atmosphere. Due to the harsh conditions under which these reactions take place (high temperature and H2 pressure), the mechanism by which they occur is only partially understood, and any study at the molecular level that reveals new mechanistic possibilities in this area is of great interest. Herein, we unravel the pyridine ring-opening mechanism of 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen) ligands coordinated to the cis-{Re(CO)2(N-RIm)(PMe3)} (N-RIm= N-alkylimidazole) fragment under mild conditions. Computational calculations show that deprotonation of the pyridine ring, once dearomatized, is crucial to induce ring contraction, triggering extrusion of the nitrogen atom from the ring and cleavage of the C-N bond. It is noteworthy that different products (regioisomers) are obtained depending on whether the ligand used is bipy or phen due to the additional rigidity and stability conferred by the central ring of the phen ligand, an issue also addressed and clarified computationally. Strong support for the proposed mechanism is provided by the characterization and isolation, including three single-crystal X-ray diffraction structures, of several of the proposed reaction intermediates.

Controlled Molecular Arrangement of Cinnamic Acid in Layered Double Hydroxide through pi-pi Interaction for Controlled Release.

Cinnamic acid (CA) was successfully incorporated into Zn-Al layered double hydroxide (LDH) through coprecipitation. The CA moiety was stabilized in the interlayer space through not only electrostatic interaction but also intermolecular π-π interaction. It was noteworthy that the CA arrangement was fairly independent of the charge density of LDH, showing the important role of the layer-CA and CA-CA interactions in molecular stabilization. Computer simulations using the Monte Carlo method as well as analytical approaches including infrared, UV-vis spectroscopy, and differential scanning calorimetry showed the existence of intermolecular interaction. In order to reinforce molecular stabilization, a neutral derivative of CA, cinnamaldehyde (CAD), was additionally incorporated into LDH. It was clearly shown that CAD played a role as a π-π interaction mediator to enhance the stabilization of CA. The time-dependent release of CA from LDH was first governed by the layer charge density of LDH; however, the existence of CAD provided additional stabilization to the CA arrangement to slow down the release kinetics.

CsPbBr3/Porous‐SiO2 Composite Film for Efficient Perovskite Light‐Emitting Diodes

AbstractThis study aims to enhance the performance of inorganic perovskite light‐emitting diodes (PeLEDs) by incorporating porous silica (p‐SiO2) to fabricate perovskite‐composite films for electroluminescence (EL) devices. This is because, in addition to the inorganic perovskite material, composites with inherently stable materials are needed for perovskite to ensure additional external stability. The introduced p‐SiO2 particles impede the crystal growth of perovskite during the anti‐solvent assisted crystallization process, resulting in the formation of smaller CsPbBr3 crystals in the CsPbBr3/p‐SiO2 composite film. Accordingly, compared to previous CsPbBr3 films, this composite film exhibits two folds with higher photoluminescence quantum yield (PLQY) due to improved crystalline formation. Surprisingly, the CsPbBr3/p‐SiO2 composite film additionally has good water‐resistant properties because the residual cetyltrimethylammonium bromide (CTAB) molecules are extracted from the p‐SiO2 particles and are oriented at the top surface of the CsPbBr3/p‐SiO2 composite film. The EL device fabricated with this composite film exhibits outstanding luminescence efficiency, with a current efficiency (CE) of 70.06 cd A−1 and an external quantum efficiency (EQE) of 16.97%, surpassing control samples by two folds of magnitude. Furthermore, the operational stability improves approximately sevenfold compared to the control, presenting a promising strategy for advancing the field of inorganic perovskite ELs.

Key arginine residues in R2D2 dsRBD1 and dsRBD2 lead the siRNA recognition in Drosophila melanogaster RNAi pathway

In Drosophila melanogaster, Dcr-2:R2D2 heterodimer binds to the 21 nucleotide siRNA duplex to form the R2D2/Dcr-2 Initiator (RDI) complex, which is critical for the initiation of siRNA-induced silencing complex (RISC) assembly. During RDI complex formation, R2D2, a protein that contains three dsRNA binding domains (dsRBD), senses two aspects of the siRNA: thermodynamically more stable end (asymmetry sensing) and the 5′-phosphate (5'-P) recognition. Despite several detailed studies to date, the molecular determinants arising from R2D2 for performing these two tasks remain elusive. In this study, we have performed structural, biophysical, and biochemical characterization of R2D2 dsRBDs. We found that the solution NMR-derived structure of R2D2 dsRBD1 yielded a canonical α1-β1-β2-β3-α2 fold, wherein two arginine salt bridges provide additional stability to the R2D2 dsRBD1. Furthermore, we show that R2D2 dsRBD1 interacts with thermodynamically asymmetric siRNA duplex independent of its 5′-phosphorylation state, whereas R2D2 dsRBD2 prefers to interact with 5'-P siRNA duplex. The mutation of key arginine residues, R53 and R101, in concatenated dsRBDs of R2D2 results in a significant loss of siRNA duplex recognition. Our study deciphers the active roles of R2D2 dsRBDs by showing that dsRBD1 initiates siRNA recognition, whereas dsRBD2 senses 5′-phosphate as an authentic mark on functional siRNA.

Equilibrium Dynamics of Infinite-Range Quantum Spin Glasses in a Field

We determine the low-energy spectrum and Parisi replica-symmetry-breaking function for the spin-glass phase of the quantum Ising model with infinite-range random exchange interactions and transverse and longitudinal (h) fields. We show that, for all h, the spin-glass state has full replica symmetry breaking and the local spin spectrum is gapless, with a spectral density that vanishes linearly with frequency. These results are obtained using an action functional—argued to yield exact results at low frequencies—that expands in powers of a spin-glass order parameter, which is bilocal in time, and a matrix in replica space. We also present the exact solution of the infinite-range spherical quantum p-rotor model at nonzero h: here, the spin-glass state has one-step replica symmetry breaking and gaplessness only appears after imposition of an additional marginal stability condition. Possible connections to experiments on random arrays of trapped Rydberg atoms are noted. Published by the American Physical Society 2024

Improving mental arithmetic ability of primary school students with schema teaching method: An experimental study.

Skillful utilization of mental arithmetic can significantly improve students' mathematical computation ability. However, it was observed that primary school students often resort to reiterating the process of written arithmetic in their minds during mental arithmetic, which is not conducive to their numerical ability improvement. This paper devises a set of graphic teaching aids for primary school students' mental arithmetic improvement based on mental arithmetic strategies, schema theory, and working memory. To validate the effectiveness of schema teaching in enhancing mental arithmetic ability among primary school students, a controlled experiment was conducted with two groups of third-grade students randomly selected from a primary school in Jingshan City. The results, obtained through descriptive statistical analysis and the multitrait-multimethod approach (MTMM), indicated that the experimental group (n = 52) demonstrated significant improvements in speed, accuracy, and stability in mental addition and subtraction after a 14-day instruction period in schema teaching. This study offers a potent mental arithmetic teaching strategy for elementary mathematics education, which can lead to a comprehensive enhancement of students' mental calculation abilities. It also holds promise for inspiring innovative teaching methodologies in primary and secondary mathematics education in the future.

Quality assurance of add-on testing in plasma samples: stability limit for 29 biochemical analytes.

Clinical laboratories should guarantee sample stability in specific storage conditions for further analysis. The aim of this study is to evaluate the stability of plasma samples under refrigeration for 29 common biochemical analytes usually ordered within an emergency context, in order to determine the maximum allowable period for conducting add-on testing. A total of 20 patient samples were collected in lithium heparin tubes without gel separator. All analyses were performed using Alinity systems (Abbott Laboratories, Abbott Park, USA) and samples were stored at 2-8 °C. Measurements were conducted in primary plasma tubes at specific time points up to 48 hours, with an additional stability study in plasma aliquots extending the time storage up to 96 hours. The stability limit was estimated considering the total limit of change criteria. Of the 29 studied parameters, 24 demonstrated stabilities within a 48-hour storage period in primary plasma tubes. However, five analytes: aspartate aminotransferase, glucose, lactate dehydrogenase, inorganic phosphate and potassium evidenced instability at different time points (7.9 hours, 2.7 hours, 2.9 hours, 6.2 hours and 4.7 hours, respectively). The stability study in plasma aliquots showed that all parameters remained stable for 96 hours, except lactate dehydrogenase, with a stability limit of 63 hours. A reduced stability of primary plasma samples was observed for five common biochemical analytes ordered in an emergency context. To ensure the quality of add-on testing for these samples, plasma aliquots provide stability for a longer period.

Phosphine-Catalyzed Synthesis and Cytotoxic Evaluation of Michael Adducts of the Sesquiterpene Lactone Arglabin.

A general method for chemo- and diastereoselective modification of anticancer natural product arglabin with nitrogen- and carbon-centered pronucleophiles under the influence of nucleophilic phosphine catalysts was developed. The locked s-cis-geometry of α-methylene-γ-butyrolactone moiety of arglabin favors for the additional stabilization of the zwitterionic intermediate by electrostatic interaction between phosphonium and enolate oxygen centers, leading to the unprecedentedly high efficiency of the phosphine-catalyzed Michael additions to this sesquiterpene lactone. Using n-Bu3P as the catalyst, pyrazole, phthalimide, 2-oxazolidinone, 4-quinazolinone, uracil, thymine, cytosine, and adenine adducts of arglabin were obtained. The n-Bu3P-catalyzed reaction of arglabin with active methylene compounds resulted in the predominant formation of bisadducts bearing a new quaternary carbon center. All synthesized Michael adducts and previously obtained phosphorylated arglabin derivatives were evaluated in vitro against eleven cancer and two normal cell lines, and the results were compared to those of natural arglabin and its dimethylamino hydrochloride salt currently used as anticancer drugs. 2-Oxazolidinone, uracil, diethyl malonate, dibenzyl phosphonate, and diethyl cyanomethylphosphonate derivatives of arglabin exhibited more potent antiproliferative activity towards several cancer cell lines and lower cytotoxicity towards normal cell lines in comparison to the reference compounds, indicating the feasibility of the developed methodology for the design of novel anticancer drugs with better therapeutic potential.

Single-molecule epitranscriptomic analysis of full-length HIV-1 RNAs reveals functional roles of site-specific m6As

Although the significance of chemical modifications on RNA is acknowledged, the evolutionary benefits and specific roles in human immunodeficiency virus (HIV-1) replication remain elusive. Most studies have provided only population-averaged values of modifications for fragmented RNAs at low resolution and have relied on indirect analyses of phenotypic effects by perturbing host effectors. Here we analysed chemical modifications on HIV-1 RNAs at the full-length, single RNA level and nucleotide resolution using direct RNA sequencing methods. Our data reveal an unexpectedly simple HIV-1 modification landscape, highlighting three predominant N6-methyladenosine (m6A) modifications near the 3′ end. More densely installed in spliced viral messenger RNAs than in genomic RNAs, these m6As play a crucial role in maintaining normal levels of HIV-1 RNA splicing and translation. HIV-1 generates diverse RNA subspecies with distinct m6A ensembles, and maintaining multiple of these m6As on its RNAs provides additional stability and resilience to HIV-1 replication, suggesting an unexplored viral RNA-level evolutionary strategy.

Is Using a Ring External Fixator in the Treatment of Congenital Pseudarthrosis of the Tibia Associated With Better Results or Using a Locking Plate?

Congenital pseudarthrosis of the tibia (CPT) is a rare disease. CPT is often unilateral and occurs between the middle and distal third of the tibia. Concurrent involvement of the fibula is present in more than half of cases. histologic studies indicate the presence of fibrous hamartoma tissue and a sick periosteum, which leads to recalcitrant bone fracture and, eventually, pseudoarthrosis. Although there are various surgical techniques, we intend to compare the 2 methods of external fixation versus internal plating. Demographic data were collected from 26 patients with frank pseudoarthrosis. After exclusion criteria, patients were compared in groups A (12 patients) and B (11 patients). Resection of hamartoma and sclerotic bone, intramedullary rodding and autologous bone, and periosteal grafting were performed for all patients. In group A, we used a ring external fixator for compression and rotational stability, but in group B, a locking plate was used for these purposes. Plating takes less time to use during surgery. In group A, the primary bony union was obtained in 67% of patients, while in group B, 82% of patients had a primary union. Meanwhile, the average time till the final union in group A was 6 months, while in group B, this time was 3.5 months. Positive union mass was obtained in 58% of the patients in group A and 82% of group B. In addition, plating prevented ankle valgus deformity in group B. Permanent intramedullary rodding is a surgical requirement for correction of deformity and refracture prevention, but additional stability can be achieved with the use of a ring external fixator or internal plate. Cross union and positive union mass are 2 important factors in the treatment of pseudoarthrosis; these results are achieved to a greater extent and in a shorter period of time using the plate. level IV - case series.