Average Cross-sectional Area Research Articles

Oral administration of a locally isolated Lactobacillus rhamnosus (NR_113332.1) improves regeneration of extensor digitorum longus muscle in mice

ObjectiveThe aim of this study was to examine the effects of probiotic supplementation on extensor digitorum longus (EDL) regeneration after grafting in mice. MethodsEDL muscles were ortho-transplanted in mice. The experimental group was given 1 × 108 colony-forming units/g body weight of Lactobacillus rhamnosus daily after EDL muscle transplantation surgeries. EDL muscle transplants were recovered after 3, 5, 7, and 14 d post-transplantation from the control as well as the experimental animals and processed for histologic analysis. ResultsAt day 3 post-transplantation, the inflammatory cells had infiltrated into the grafted EDL muscles and the central section of the grafted tissue contained necrotic fibers. At day 5 post-transplantation, the concentration of inflammatory cells increased further and degenerative muscle fibers were being replaced with centrally nucleated muscle cells. The average cross-sectional area non-grafted EDL and grafted muscle in the probiotic supplemented mice at day 7 increased to 48% and 23% (P = 0.002), respectively, compared with the respective values in the control animals. Whereas in non-grafted and grafted EDL muscle it could approach 8% and 36% (P = 0.008), respectively at 14 d compared with the corresponding values of the control EDL muscle transplants. The number of muscle fibers in the non-grafted and grafted probiotic-supplemented groups increased to12% and 20% (P = 0.045) at day 7 compared with the control EDL muscle. In non-grafted and grafted EDL muscle, the number of regenerated muscle fibers increased to 73% and 64% (P = 0.110) at day 14 compared with control EDL grafted muscle. ConclusionResults of the present study regarding better regeneration of skeletal muscle fibers in the probiotic-supplemented mice than the control grafts warrant further molecular-level investigation to understand the underlying mechanism mediating the process of skeletal muscle fiber regeneration. Probiotics possibly modulate the process of muscle fiber regeneration by adjusting the composition of gut microbiota.

Отдаленные результаты лечения многоуровневого стеноза позвоночного канала в шейном отделе позвоночника методом билатеральной костно-пластической декомпрессивной ламинопластики с одномоментной фораминотомией

Introduction Stenosis of the cervical spine can lead to serious complications resulting from spinal cord dysfunction. There are different methods of posterior decompression of the spinal canal. The method of choice for surgical treatment of cervical stenosis is laminoplasty. Purpose Analysis of long-term (from 2 to 5 years) results of clinical outcomes after bilateral decompression laminoplasty and simultaneous foraminotomy Materials and methods Study design: case series (27 patients); a single center retro/prospective study. Patients who were treated at the Federal Center for Neurosurgery in Tyumen were examined. In the pre- and postoperative periods, the clinical condition of patients was assessed using questionnaires and scales JOA, VAS, Nurick. The stenosis severity was objectively assessed using a standard closed polygon measuring instrument. The cross-sectional area of the dural sac and the average linear dimensions were measured according to neuroimaging data. Results In the late postoperative period, patients had positive dynamics in pain relief, improvement in motor functions, and partial recovery of sensory disorders. There was a slight increase in the average cross-sectional area of the dural sac measured at the follow-up. Discussion The method of bilateral osteoplastic laminoplasty is one of the surgical treatment options and allows full visualizing of the neurovascular structures, as well as safe performance of hemostasis and foraminotomy at the levels of interest. Conclusion Thus, the effectiveness of this technique was shown by this study.

VEGFA Promotes Skeletal Muscle Regeneration in Aging.

Aging is associated with loss of skeletal muscle regeneration. Differentially regulated vascular endothelial growth factor (VEGF)A with aging may partially underlies this loss of regenerative capacity. To assess the role of VEGFA in muscle regeneration, young (12-14weeks old) and old C57BL/6 mice (24,25 months old) are subjected to cryoinjury in the tibialis anterior (TA) muscle to induce muscle regeneration. The average cross-sectional area (CSA) of regenerating myofibers is 33% smaller in old as compared to young (p<0.01) mice, which correlates with a two-fold loss of muscle VEGFA protein levels (p=0.02). The capillary density in the TA is similar between the two groups. Young VEGFlo mice, with a 50% decrease in systemic VEGFA activity, exhibit a two-fold reduction in the average regenerating fiber CSA following cryoinjury (p< 0.01) in comparison to littermate controls. ML228, a hypoxia signaling activator known to increase VEGFA levels, augments muscle VEGFA levels and increases average CSA of regenerating fibers in both old mice (25% increase, p<0.01) and VEGFlo (20% increase, p<0.01) mice, but not in young or littermate controls. These results suggest that VEGFA may be a therapeutic target in age-related muscle loss.

The crystalline structure transition and hydrogen bonds shift determining enhanced enzymatic digestibility of cellulose treated by ultrasonication

Global energy issue raised the necessity to develop second-generation biofuels, and biorefinery of cellulosic biomass becomes a promising solution. Various pretreatments were used to overcome the cellulose nature of recalcitrance and improve the enzymatic digestibility, but the lack of mechanism understanding hindered the development of efficient and cost-effective technologies of cellulose utilization. Using structure-based analysis, we demonstrate that the improved hydrolysis efficiency caused by ultrasonication was ascribed to the changed cellulose properties rather than the increased dissolubility. Further, isothermal titration calorimetry (ITC) analysis suggested that enzymatic digestion of cellulose is an entropically favored reaction driven by hydrophobic forces other than an enthalpically favored reaction. The changes in cellulose properties and thermodynamic paramenters due to ultrasonication accounted for the improved accessibility. Ultrasonication-treated cellulose showed porous, rough and disordered morphology, accompanying with the loss of crystalline structure. Despite the unaffected unit cell structure, ultrasonication expanded the crystalline lattice by increasing grain sizes and average cross-sectional area, resulting in the transformation from cellulose I to cellulose II, with the decreased crystallinity, better hydrophilicity and increased enzymatic bioaccessibility. Furthermore, FTIR combined with two-dimensional correlation spectroscopy (2D-CoS) verified that the sequential shift of hydroxyl group and intramolecular/intermolecular hydrogen bonds, the functional groups governing cellulose crystal structure and stability, accounted for the ultrasonication-induced transition of cellulose crystalline structure. This study provides a comprehensive picture of cellulose structure and property response caused by mechanistic treatments and will open up avenues to develop novel pretreatments for efficient utilization.

A morphological study of bicontinuous concentric lamellar silica synthesized at atmospheric pressure and its application as an internal micro-reflector in dye-sensitized solar cells.

KCC-1, a nanostructured silica material with a bicontinuous concentric lamellar (bcl) morphology, provides plenty of functional characteristics, such as an open channel structure, excellent accessibility, and a large surface area. Although bcl silica exhibits various superior properties, studies on its morphology and its application in dye-sensitized solar cells (DSSCs) are still limited. Therefore, this work aims to study the influence of the synthesis time on the morphology of bcl silica. Moreover, we used the synthesized bcl silica as internal micro-reflectors in DSSCs. The bcl silica was synthesized using the reflux method by varying synthesis times. The morphology of bcl silica was observed using FESEM and HRTEM. FESEM images show that bcl silica has bicontinuous lamellar walls arranged concentrically to form spherical particles. As the synthesis time increases, the average particle size of bcl silica increases. The quantization of bcl silica binary images shows that the average lamellar cross-sectional area ratio decreases with increasing synthesis time. The simulation of the Cahn-Hilliard's spinodal decomposition model using MATLAB also describes the lamellar cross-sectional area ratio of bcl silica. In addition, to characterize the FESEM image's texture, a Shannon entropy calculation was performed. The line and circular gray value intensity profiles of the HRTEM image show that bcl silica has a denser core than the outer part. The denser core proves that the lamellae in bcl silica are concentrically arranged towards the particle core. Furthermore, we added bcl silica to a photoanode to see the effect of bcl characteristics on the DSSC performance. The results show that the bcl silica significantly improves the light-harvesting efficiency in DSSCs due to its low refractive index and open channel structure.

Evaluation of Tibial nerve morphology by high resolution ultrasonography in diabetic patients with clinically suspected diabetic peripheral neuropathy: A cross sectional study

Background: Diabetic peripheral neuropathy is diagnosed by nerve conduction studies by presence of atypical parameters with respect to amplitude, latency as well as conduction velocity of nerve. In adjunct to current screening modalities, use of ultrasonography for evaluation of peripheral neuropathy in diabetic patients has been advocated as a promising diagnostic tool. The purpose of this study is to evaluate & measure Cross-sectional area of tibial nerve & maximum thickness of nerve fascicles of tibial nerve in diabetic patients with clinical suspicion of diabetic peripheral neuropathy by ultrasonography & its correlation with clinical symptoms, duration of diabetes & HbA1c. Materials and methods: This cross-sectional study was conducted in Mahatma Gandhi Medical College and Research Institute from January 2021 to June 2022 amongst 30 clinically suspected diabetic peripheral neuropathy patients. Results: The mean age, Hb1Ac & duration of diabetes was found to be 67.83, 10.08 & 21.27, with a male predominance (26 males & 4 females). Average Cross sectional area of tibial nerve, maximum thickness of nerve fascicles of tibial nerve & average total Toronto clinical neuropathy score was found to be 23.82 mm2, 0.68 mm & 10.23 respectively. Correlation of duration of diabetes, HbA1c as well as Toronto neuropathy score against average Cross sectional area of tibial nerve, average maximum thickness of nerve fascicles of tibial nerve in both limbs was found to be statistically significant with a strong positive correlation. Conclusion: High resolution ultrasonography is efficient in detecting morphological changes in tibial nerve in clinically suspected diabetic neuropathic patients. Cross-sectional area and maximum thickness of nerve fascicles of tibial nerve were found to be significantly higher than typical cut off values used in this study and high-resolution ultrasound is an important tool for diagnosis of diabetic peripheral neuropathy.

Магнитно-резонансно-томографическая анатомия половых нервов у мужчин зрелого возраста после выполнения оперативных вмешательств на органах малого таза

The work studied the magnetic resonance imaging (MRI) anatomy of the pudendal nerves in mature men who underwent surgery on pelvic organs. The study included 75 patients (30 patients in the first period of adulthood and 45 patients in the second period of adulthood). Thirty-seven patients underwent prostatectomy and 38 respondents underwent rectal resection. The single-trunk nature of the branching of the nerve, in which the pudendal nerve passes under the sacrospinous ligament, was found in the majority of patients (65.3%). The sources of formation of the pudendal nerves in 45 (60.0%) cases were the roots S2, S3 and S4, in 19 (25.3%) respondents the pudendal nerves were formed from the roots S2 and S4 and in 11 (14.6%) of respondents, the nerves originated from the S3 and S4 roots. The genital canals originate 22.5±3.2 mm below the ischial tuberosity and lie 39.8±9.5 mm anterior to it, the canals end at the level of the lower edge of the pubic symphysis 24.4±10.9 mm behind it. The average cross-sectional area of the genitals was 27.9±9.2 mm2. The average diameters of the pudendal nerve trunks at a level of 2 cm distal to the piriformis muscle were 4.63 mm, 1.85 mm, and 1.64 mm for the first, second, and third trunks, respectively. The average length of the pudendal nerve trunks before division into terminal branches was 25.23 mm. A comparison of the skeletotopic characteristics of the genital canals between patients with a conditional norm and patients after surgery on the pelvic organs demonstrated the presence of significant differences (p=0.023).

Prediction of high-flow nasal cannula failure in patients with acute respiratory failure by measuring the cross-sectional area of the diaphragmatic crus and ROX index

The delayed prediction of high-flow nasal cannula (HFNC) failure is associated with poor prognosis in patients with acute respiratory failure (ARF) treated with HFNCs. This study aimed to identify the early predictors for requiring mechanical ventilation (MV) in ARF patients treated with HFNCs. This was a single-center retrospective observational study based on ARF patients older than 18 years, treated with HFNC, and had chest computed tomography (CT) scans performed in the emergency department (ED) of a tertiary hospital between July 2018 and June 2020. The demographic and laboratory data were collected, and the cross-sectional area (CSA) of the diaphragmatic crus was measured on the chest CT scan. Two hundred and twenty-nine patients with ARF (92 females and 137 males) were treated with HFNCs during the study period and included in this study. Twenty-five female patients (27.17%) and 32 male patients (23.36%) required subsequent intubation and MV and were categorized as HFNC failures. Their respiratory rate-oxygenation (ROX) indexes were acquired at two hours, and the average CSA of the diaphragmatic crura was integrated to analyze the predictive power, which showed good predictive accuracy in both gender groups (area under the receiver operating characteristic curves (AUROC) for females, 0.778, and males, 0.782). The optimal ROC curve cutoff point for the average CSA of the diaphragmatic crus was estimated to be 1.48 cm2 in female patients and 1.64 cm2 in male patients. Altogether, these results indicated that the CSA measurement of the diaphragmatic crus on CT in ARF patients might help predict the risk of HFNC failure.

Abstract 10430: Radial First! Ulnar Next? Forearm Arterial Anatomy Study

Introduction: In patients with small Right Radial Artery ( RRA ), access site failure may result in a radial to femoral crossover. Methods: The arterial anatomy of the distal forearm was studied using ultrasound in 167 hospitalized patients. The radial and ulnar artery dimensions were imaged in triplicates. The average cross-sectional area (CSA) and average diameter (AD) were measured using open-source ImageJ software. Variations in distal forearm arterial anatomy (branches) were documented. Results: The mean CSA and AD for the largest of the bilateral radial and ulnar arteries - Largest Forearm Artery ( LFA ), were 5.4 ± 2.5 mm 2 (1.1 → 13.3 mm 2 ) and 2.6 ± 0.6 mm (1.2 → 4.1 mm) respectively. The mean CSA and AD for RRA were 4.8 ± 2.5 mm 2 (0.7 → 13.3 mm 2 ) and 2.4 ± 0.6 mm (0.9 → 4.1 mm). In 46% of patients, RRA was not the LFA. The ulnar artery was larger than the radial artery in 25% of patients in the right wrist and 29% in the left wrist. The left radial was larger than the right radial in 31% and the left ulnar was larger than the right ulnar in 42%. In 58% of patients, RRA was &lt; 2.5 mm (outer diameter of common radial access sheaths). In 24% of patients, RRA was &lt;2 mm. In patients with RRA &lt; 2.5 mm, 17% had another artery &gt;2.5 mm and 6% had another artery &gt; 3 mm. Men had 53% larger CSA compared to women. Smoking, intravenous drug use, diabetes, hyperlipidemia, peripheral vascular disease, chronic kidney disease (CKD), and hemodialysis predicted smaller-sized forearm arteries. CKD patients had 33% smaller CSA compared to patients without CKD. In 23 patients (14%), one or more of the forearm arteries had branches in the distal forearm. In 12 patients (7%), branches were seen in RRA. Conclusions: Right Radial Artery was not the largest forearm artery in almost half the patients. Right Radial Artery was smaller in size than common radial access sheaths in more than half of the patients. Of these patients, 17% had a different forearm artery &gt; 2.5 mm that could be accessed instead of Femoral Artery. Female sex and CKD predicted smaller forearm artery sizes increasing the risk of radial access failure. Ultrasound use is advisable to identify the best forearm artery for access and avoid accessing smaller accessory branches that were seen in 7% of right radial and 14% of one or more forearm arteries.

Effects of Changing Drive Control Method of Idling Wood Size Reduction Machines on Fuel Consumption and Exhaust Emissions

Operating conditions often fluctuate during processing of branches and sawmill offcuts using low-power wood size reduction machines (WSRMs), mainly due to changes in wood supply frequency. This results in relatively high proportions of idling time. Fuel consumption and associated exhaust emissions of WSRMs with combustion engines can be reduced by using innovative drive unit control systems during idling. The objective of the research was to determine the effects of two speed control systems on the fuel consumption and exhaust emissions of a WSRM with a two-cylinder cutting mechanisms driven by a small 9.5 kW spark ignition engine. Speed control system A (commercially available) had a substantially higher rotational speed than system B (an innovative, adaptive solution subject to patent application No. P433586). Pine (Pinus sylvestris L.) wood sawmill offcuts (average cross-sectional area, length and water content: 25×40 mm, 3000 mm and ca. 12, respectively) were used in system tests at a feed rate of ca. 5 pieces min-1. Material of this size is typically processed by such machines. Operating conditions were monitored by recording the rotational speed and torque. Emissions of harmful exhaust compounds–carbon monoxide (CO), carbon dioxide (CO2), hydrocarbons (HC), and nitrogen oxides (NOx) – were recorded using a portable emission measurement system. Fuel consumption values were also calculated from the data. The following effects were observed: application of innovative system B resulted in 33% lower fuel consumption, as well as 30%, 37% and 33% lower CO, CO2 and NOx emissions, respectively, than system A, but at the same time 290% higher HC emissions were registered. In operating conditions with higher proportions of idling time, solution B provides even higher reductions in fuel consumption and exhaust emissions.

Immunohistochemical characteristics of local sites that trigger atrial arrhythmias in response to high-frequency stimulation.

The response to high frequency stimulation (HFS) is used to locate putative sites of ganglionated plexuses (GPs), which are implicated in triggering atrial fibrillation (AF). To identify topological and immunohistochemical characteristics of presumed GP sites functionally identified by HFS. Sixty-three atrial sites were tested with HFS in four Langendorff-perfused porcine hearts. A 3.5 mm tip quadripolar ablation catheter was used to stimulate and deliver HFS to the left and right atrial epicardium, within the local atrial refractory period. Tissue samples from sites triggering atrial ectopy/AF (ET) sites and non-ET sites were stained with choline acetyltransferase (ChAT) and tyrosine hydroxylase (TH), for quantification of parasympathetic and sympathetic nerves, respectively. The average cross-sectional area (CSA) of nerves was also calculated. Histomorphometry of six ET sites (9.5%) identified by HFS evoking at least a single atrial ectopic was compared with non-ET sites. All ET sites contained ChAT-immunoreactive (ChAT-IR) and/or TH-immunoreactive nerves (TH-IR). Nerve density was greater in ET sites compared to non-ET sites (nerves/cm2: 162.3 ± 110.9 vs. 69.65 ± 72.48; P = 0.047). Overall, TH-IR nerves had a larger CSA than ChAT-IR nerves (µm2: 11 196 ± 35 141 vs. 2070 ± 5841; P < 0.0001), but in ET sites, TH-IR nerves were smaller than in non-ET sites (µm2: 6021 ± 14 586 vs. 25 254 ± 61 499; P < 0.001). ET sites identified by HFS contained a higher density of smaller nerves than non-ET sites. The majority of these nerves were within the atrial myocardium. This has important clinical implications for devising an effective therapeutic strategy for targeting autonomic triggers of AF.

Age-related changes of neurons from the large intestine containing neuronal nitric oxide synthase

The aim of the study was to identify the localization, percentage and morphometric characteristics of neuronal NO synthase (nNOS)-immunoreactive (IR) neurons in the intramural ganglia of the myenteric (MP) and submucous plexus (SP) of the large intestine of rats of different age groups.&#x0D; Material and methods. The work was performed on Wistar rats aged 1, 10, 20, 30, 60 days and 2 years using immunohistochemical methods.&#x0D; Results. nNOS-IR neurons were found in the large intestine from the moment of birth and during the remaining age periods. In the intramural ganglia of the MP, the largest percentage of nNOS-IR neurons was detected in the newborn rat and decreased in ontogenesis up to 60 days of life, then did not change until senescence. In the SP, nNOS-IR neurons were also detected in the greatest number in newborns, in the next 20 days the percentage decreased significantly, nNOS-IR neurons were not detected in 30-day and two-month-old animals, but again appeared in large numbers in aged rats. The average cross-sectional area of nNOS-IR neurons increased in the MP from birth during the first two months of life. In the SP, the average size of nNOS-IR cells increased in the first 30 days of life and was significantly larger in aged rats compared with other ages.&#x0D; Conclusions. In early postnatal ontogenesis, there is a decrease in the expression of nNOS in neurons of the large intestine and a subsequent increase in aged rats.

Biceps femoris long head morphology in youth competitive alpine skiers is associated with age, biological maturation and traumatic lower extremity injuries.

Lower extremity injuries are common in competitive alpine skiers, and the knee and lower leg are often affected. The hamstring muscles, especially the biceps femoris long head (BFlh), can stabilize the knee and the hip and may counteract various adverse loading patterns during typical mechanisms leading to severe lower extremity injuries. The aim of the present study was to describe BFlh morphology in youth competitive alpine skiers in relation to sex, age and biological maturation and to investigate its association with the occurrence of traumatic lower extremity injuries in the upcoming season. 95 youth skiers underwent anthropometric measurements, maturity offset estimations and ultrasound assessment, followed by 12-months prospective injury surveillance. Unpaired t tests showed that the two sexes did not differ in BFlh morphology, including fascicle length (Lf), pennation angle (PA), muscle thickness (MT) and average anatomical cross-sectional area (ACSAavg). In contrast, U16 skiers had longer fascicles than U15 skiers (9.5 ± 1.3 cm vs 8.9 ± 1.3 cm, p < 0.05). Linear regression analyses revealed that maturity offset was associated with Lf (R 2 = 0.129, p < 0.001), MT (R 2 = 0.244, p < 0.001) and ACSAavg (R 2 = 0.065, p = 0.007). No association was found between maturity offset and PA (p = 0.524). According to a binary logistic regression analysis, ACSAavg was significantly associated with the occurrence of traumatic lower extremity injuries (Chi-square = 4.627, p = 0.031, RNagelkerke 2 = 0.064, Cohen f = 0.07). The present study showed that BFlh morphology is age- and biological maturation-dependent and that BFlh ACSAavg can be considered a relevant modifiable variable associated with lower extremity injuries in youth competitive alpine skiers.

Circulatory disturbance of the cochlear spiral modiolar artery in a type 2 diabetic mouse model.

ObjectiveThis study aimed to identify significant differences in cochlea microvessel size between a diabetic mouse model (db/db) and normal mice using three‐dimensional (3D) quantitative analysis.MethodsSix control heterozygote db/+ as well as 18 male B6/BKS(D)‐Leprdb/J (db/db) mice aged 14 (n = 9) and 28 (n = 9) weeks were examined. After clearing the cochlea, we reconstructed the 3D volumes of the spiral modiolar artery (SMA) in the cochlea using light‐sheet microscopy and analyzed vessel wall thickness, cross‐sectional area, short and long diameter, and vessel height.ResultsThe average SMA‐wall thickness in the db/db‐mouse group (3.418 ± 0.328 μm) was greater than that in the control group (2.388 ± 0.411 μm). The average cross‐sectional outer area, short diameter, and long diameter of the SMA in db/db mice were significantly larger than those in control mice (all p < 0.001). The cross‐sectional areas increased with age (control: 221.782 ± 121.230 μm, 14 weeks; 294.378 ± 151.008 μm, and 28 weeks; 312.925 ± 147.943 μm).ConclusionThe db/db mice had thicker and larger proximal‐SMA vessel walls and diameters than control mice, respectively, thus potentially inducing increased blood viscosity or vascular insufficiency and aggravating hearing loss in type 2 diabetes mellitus.Level of EvidenceIIb

Three-dimensional volumetric changes in the airway of growing unilateral complete cleft lip and palate patients after bone-anchored maxillary protraction

This prospective controlled study evaluates volumetric, length, and average cross-sectional area (aCSA) airway changes in growing patients with unilateral complete cleft lip and palate after 1.5 years of bone-anchored maxillary protraction therapy. Thirty-five growing unilateral complete cleft lip and palate patientswith maxillary deficiency were included (aged 11.3 ± 0.5 years). Cone-beam computed tomography scans were obtained before bone-anchored maxillary protraction (BAMP) therapy and after 1.5 years. Agrowing group without cleft (n= 18) patients served as a control group at 1.5 years posttreatment (aged 13.1 ± 1.2 years). Volumetric, length, and aCSA changes of the total airway, nasopharynx (NP), middle pharynx, and inferior pharynx airway were evaluated. After 1.5 years of BAMP therapy, a significant increase was observed in the total airway volume and the NP (P<0.01). The middle and inferior pharynx showed an insignificant tendency of volumetric increase. Compared with the control group, a significantly larger airway volume could be observed in the total airway and NP (P<0.05). The aCSA of the NP increased significantly compared with pretreatment. The total airway and NP volumes significantly increased in growing subjects with cleft lip and palate after 1.5 years of BAMP therapy to a level comparable to a control group without cleft. Volumetric increase in the NP in the BAMP group is mainly attributed to the increase in its cross-sectional area. BAMP can therefore be recommended as an effective therapy for patients with cleft lip and palate with positive effects on airway development.

Predicting tracheal work of breathing in neonates based on radiological and pulmonary measurements.

Tracheomalacia is an airway condition in which the trachea excessively collapses during breathing. Neonates diagnosed with tracheomalacia require more energy to breathe, and the effect of tracheomalacia can be quantified by assessing flow-resistive work of breathing (WOB) in the trachea using computational fluid dynamics (CFD) modeling of the airway. However, CFD simulations are computationally expensive; the ability to instead predict WOB based on more straightforward measures would provide a clinically useful estimate of tracheal disease severity. The objective of this study is to quantify the WOB in the trachea using CFD and identify simple airway and/or clinical parameters that directly relate to WOB. This study included 30 neonatal intensive care unit subjects (15 with tracheomalacia and 15 without tracheomalacia). All subjects were imaged using ultrashort echo time (UTE) MRI. CFD simulations were performed using patient-specific data obtained from MRI (airway anatomy, dynamic motion, and airflow rates) to calculate the WOB in the trachea. Several airway and clinical measurements were obtained and compared with the tracheal resistive WOB. The maximum percent change in the tracheal cross-sectional area (ρ = 0.560, P = 0.001), average glottis cross-sectional area (ρ = -0.488, P = 0.006), minute ventilation (ρ = 0.613, P < 0.001), and lung tidal volume (ρ = 0.599, P < 0.001) had significant correlations with WOB. A multivariable regression model with three independent variables (minute ventilation, average glottis cross-sectional area, and minimum of the eccentricity index of the trachea) can be used to estimate WOB more accurately (R2 = 0.726). This statistical model may allow clinicians to estimate tracheal resistive WOB based on airway images and clinical data.NEW & NOTEWORTHY The work of breathing due to resistance in the trachea is an important metric for quantifying the effect of tracheal abnormalities such as tracheomalacia, but currently requires complex dynamic imaging and computational fluid dynamics simulation to calculate it. This study produces a method to predict the tracheal work of breathing based on readily available imaging and clinical metrics.

Experimental investigation on the deterioration process and spatial variation of corrosion damage of RC segmental specimens under sustained load

• Early deterioration damage of a bearing segment is investigated via AE technique. • Effect of sustained load on spatial variability of steel corrosion is studied. • Spatial correlation between steel corrosion and surface corrosion cracks is studied. For the reinforced concrete (RC) shield tunnel in coastal regions, premature corrosion damages are always investigated after construction because of the combined effects of sustained earth and water pressures and marine chloride attacks. To evaluate the performance of these deteriorated shield tunnels, the effect of sustained load on structural performance degradation must be considered. In this paper, an experiment was conducted using the corrosion-accelerated specimens of a tunnel segment. The deteriorating damage processes of the RC segmental specimens were illustrated via acoustic emission (AE) with an emphasis on the influence of sustained load. Based on AE intensity analysis, intensive cracking damages for a bearing segment were identified when the average steel cross-section area losses increased from 0.5% to 2%. Meanwhile, the spatial variations of corrosion damage were discussed incorporating the impact of tensile load. The effect of tensile load on spatial correlation of distribution between steel cross-section area loss and surface corrosion cracks was experimentally verified. The experimental outcomings can help in modelling a random field-based probabilistic model associated with non-uniform steel corrosion in the bearing segmental linings.

Sarcopenia Is Associated With Increased Mortality in Patients With Necrotizing Soft Tissue Infections.

Necrotizing soft tissue infections (NSTIs) are surgical emergencies associated with high morbidity and mortality. Identifying risk factors for poor outcome is a critical part of preoperative decision-making and counseling. Sarcopenia, the loss of lean muscle mass, has been associated with an increased risk of mortality and can be measured using cross-sectional imaging. Our aim was to determine the impact of sarcopenia on mortality in patients with NSTI. We hypothesized that sarcopenia would be associated with an increased risk of mortality in patients with NSTI. This is a retrospective cohort study of NSTI patients admitted from 1995 to 2015 to two academic institutions. Operative and pathology reports were reviewed to confirm the diagnosis in all cases. Average bilateral psoas muscle cross-sectional area at L4, normalized for height (Total Psoas Index [TPI]), was calculated using computed tomography (CT). Sarcopenia was defined as TPI in the lowest sex-specific quartile. Primary outcome was in-hospital mortality. Multivariate logistic regression was performed to assess the association between sarcopenia and in-hospital mortality. There were 115 patients with preoperative imaging, 61% male and a median age of 57y interquartile range (IQR 46.6-67.0). Overall in-hospital mortality was 12.1%. There was no significant difference in sex, body mass index (BMI), comorbidities and American Society of Anesthesiologists classification (Table1). After multivariate analysis, sarcopenia was independently associated with increased in-hospital mortality (Odds ratio, 3.5; 95% Confidence Interval [CI], 1.05-11.8). Sarcopenia is associated with increased risk of in-hospital mortality in patients with NSTIs. Sarcopenia identifies patients with higher likelihood of poor outcomes, which can possibly help surgeons in counseling their patients and families.

Mibefradil improves skeletal muscle mass, function and structure in obese mice

To observe the effect of mibefradil on skeletal muscle mass, function and structure in obese mice. Fifteen 6-week-old C57BL/6 mice were randomized equally into normal diet group (control group), high-fat diet (HFD) group and high-fat diet +mibefradil intervention group (HFD +Mibe group). The grip strength of the mice was measured using an electronic grip strength meter, and the muscle content of the hindlimb was analyzed by X-ray absorptiometry (DXA). Triglyceride (TG) and total cholesterol (TC) levels of the mice were measured with GPO-PAP method. The cross-sectional area of the muscle fibers was observed with HE staining. The changes in the level of autophagy in the muscles were detected by Western blotting and immunofluorescence assay, and the activation of the Akt/mTOR signaling pathway was detected with Western blotting. Compared with those in the control group, the mice in HFD group had a significantly greater body weight, lower relative grip strength, smaller average cross sectional area of the muscle fibers, and a lower hindlimb muscle ratio (P < 0.05). Immunofluorescence assay revealed a homogenous distribution of LC3 emitting light red fluorescence in the cytoplasm in the muscle cells in HFD group and HFD+Mibe group, while bright spots of red fluorescence were detected in HFD group. In HFD group, the muscular tissues of the mice showed an increased expression level of LC3 II protein with lowered expressions of p62 protein and phosphorylated AKT and mTOR (P < 0.05). Mibefradil treatment significantly reduced body weight of the mice, lowered the expression level of p62 protein, and increased forelimb grip strength, hindlimb muscle ratio, cross-sectional area of the muscle fibers, and the expression levels of LC3 II protein and phosphorylated AKT and mTOR (P < 0.05). Mibefradil treatment can moderate high-fat diet-induced weight gain and improve muscle mass and function in obese mice possibly by activating AKT/mTOR signal pathway to improve lipid metabolism and inhibit obesityinduced autophagy.

Chicken jejunal microbiota improves growth performance by mitigating intestinal inflammation

BackgroundIntestinal inflammation is prevalent in chicken, which results in decreased growth performance and considerable economic losses. Accumulated findings established the close relationship between gut microbiota and chicken growth performance. However, whether gut microbiota impacts chicken growth performance by lessening intestinal inflammation remains elusive.ResultsSeven-weeks-old male and female chickens with the highest or lowest body weights were significantly different in breast and leg muscle indices and average cross-sectional area of muscle cells. 16S rRNA gene sequencing indicated Gram-positive bacteria, such as Lactobacilli, were the predominant species in high body weight chickens. Conversely, Gram-negative bacteria, such as Comamonas, Acinetobacter, Brucella, Escherichia-Shigella, Thermus, Undibacterium, and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium were significantly abundant in low body weight chickens. Serum lipopolysaccharide (LPS) level was significantly higher in low body weight chickens (101.58 ± 5.78 ng/mL) compared with high body weight chickens (85.12 ± 4.79 ng/mL). The expression of TLR4, NF-κB, MyD88, and related inflammatory cytokines in the jejunum was significantly upregulated in low body weight chickens, which led to the damage of gut barrier integrity. Furthermore, transferring fecal microbiota from adult chickens with high body weight into 1-day-old chicks reshaped the jejunal microbiota, mitigated inflammatory response, and improved chicken growth performance.ConclusionsOur findings suggested that jejunal microbiota could affect chicken growth performance by mitigating intestinal inflammation.6HqdvtqqRSUUnYkCAWAGgrVideo