Small Fiber Research Articles

Postural orthostatic tachycardia syndrome after COVID-19 vaccination

There is an association between coronavirus disease 2019 (COVID-19) mRNA vaccination and the incidence or exacerbation of postural orthostatic tachycardia syndrome (POTS). The purpose of this study was to characterize patients reporting new or exacerbated POTS after receiving the mRNA COVID-19 vaccine. We prospectively collected data from sequential patients in a POTS clinic between July 2021 and June 2022 reporting new or exacerbated POTS symptoms after COVID-19 vaccination. Heart rate variability (HRV) and skin sympathetic nerve activity (SKNA) were compared against those of 24 healthy controls. Ten patients (6 women and 4 men; age 41.5 ± 7.9 years) met inclusion criteria. Four patients had standing norepinephrine levels > 600 pg/mL. All patients had conditions that could raise POTS risk, including previous COVID-19 infection (N = 4), hypermobile Ehlers-Danlos syndrome (N = 6), mast cell activation syndrome (N = 6), and autoimmune (N = 7), cardiac (N = 7), neurological (N = 6), or gastrointestinal conditions (N = 4). HRV analysis indicated a lower ambulatory root mean square of successive differences (46.19 ±24 ms; P = .042) vs control (72.49 ± 40.8 ms). SKNA showed a reduced mean amplitude (0.97 ± 0.052 μV; P = .011) vs control (1.2 ± 0.31 μV) and burst amplitude (1.67 ± 0.16 μV; P = .018) vs control (4. 3 ± 4.3 μV). After 417.2 ± 131.4 days of follow-up, all patients reported improvement with the usual POTS care, although 2 with COVID-19 reinfection and 1 with small fiber neuropathy did have relapses of POTS symptoms. All patients with postvaccination POTS had pre-existing conditions. There was no evidence of myocardial injuries or echocardiographic abnormalities. The decreased HRV suggests a sympathetic dominant state. Although all patients improved with guideline-directed care, there is a risk of relapse.

Construction of Janus structures on thin silk fabrics via misting for wet–thermal comfort and antimicrobial activity

Owing to their small fiber diameter (10–15 μm), silk fabrics are always thin (32–90 g m−2). Therefore, construction of the Janus surfaces of silk fabrics that possess excellent multifunctionality remains a formidable challenge. Herein, first, silk fabrics were grafted using glycidyltrimethylammonium chloride to form a superhydrophilic surface (G-side). Then, a unilateral hydrophobic surface (O-side) was readily fabricated by mist coating octadecyltrichlorosilane-functionalized SiO2 nanoparticles (NPs) to produce hierarchical surface textures. To prevent NP penetration from the G-side to the O-side, a “fireproof isolation” method was employed. Consequently, Janus silk fabrics (JanSFs) bearing asymmetric wettability were prepared, and their wetting gradient could be conveniently regulated. With the mist time ranging from 4 to 7 min, the unidirectional transport index and efficiency of the unidirectional water transport increased and decreased by 13.2 and 10.4 times, respectively. Sweat could be effectively drained away from human skin to ensure that the skin was dry and comfortable. Compared with the surface temperature of the raw fabric, the raw fabric of JanSFs increased by 2.7 °C. Furthermore, the breathability of JanSF was negligibly affected, and the outer O-side of the JanSF showed substantial antibacterial activity. This study is important for designing JanSFs that exhibit unidirectional water transport.

Early detection of nerve involvement in presymptomatic TTR mutation carriers: exploring potential markers of disease onset

BackgroundHereditary transthyretin (ATTRv) amyloidosis is a heterogeneous, progressive, multisystemic disease with a life-threatening course if left untreated. Given the current availability of effective therapies, close follow-up of presymptomatic TTR mutation carriers is essential to recognize disease onset at the earliest sign. In addition to routine techniques, in recent years several novel tools have been proposed, although a consensus on their use has not been reached yet. In this paper, we aimed to evaluate possible markers of neuropathic disease onset intended to discriminate clinically asymptomatic carriers from early symptomatic patients, thus allowing timely treatment initiation.MethodsThirty-eight presymptomatic carriers were enrolled. Clinical and electrophysiological findings at first evaluation and follow-up were collected. All carriers underwent an extensive clinical and instrumental evaluation according to the standard clinical practice. One or more non-routine investigations, whose use in this field is not yet validated (henceforth “unconventional”), were additionally assessed in a subgroup of individuals.ResultsBased on the exclusive use of routine investigations, it was possible to define disease onset in 4/38 carriers during the follow-up. Employing additionally one or more “unconventional” tests, abnormal findings, indicative of a possible “conversion” to symptomatic disease, were detected in further 12 cases. More than half of our study cohort showed findings suggestive of small nerve fiber (SF) involvement at either invasive or non-invasive tests.ConclusionsA close, multidisciplinary monitoring of presymptomatic TTR mutation carriers is fundamental, and diagnostic workup should include both routine and “unconventional” tests. Assessment of SF involvement is important also in non-endemic countries.

Super pulsed thulium fiber laser outcomes in retrograde intrarenal surgery for ureteral and renal stones: a systematic review and meta-analysis

BackgroundLaser lithotripsy using a thulium fiber laser (TFL) has become an effective treatment option for small renal stones with low complication rates. TFL has a higher absorption coefficient, smaller fibers, and better pulse rate capability.MethodsWe conducted a systematic review and meta-analysis to evaluate the published evidence regarding TFL's lithotripsy performance in retrograde intrarenal surgery (RIRS), for which we primarily assessed the outcomes of stone-free rate, operation time, and complications. We searched different databases from inception to April 2023. We assessed the methodological quality and risk of bias using the Cochrane Risk of Bias tool for randomized trials and the ROBINS-I tool for non-randomized studies. We used a random-effects model for meta-analysis and assessed heterogeneity using the I2 statistic.ResultsTwelve published studies evaluated the efficacy of RIRS using a TFL for treating renal and ureteral stones. The meta-analysis revealed a predicted stone-free rate of 89.37% (95% CI: 83.93% to 93.12%), indicating that, on average, approximately 89.37% of patients achieved a stone-free state after treatment. The substantial heterogeneity among the studies was evident, as shown by a Q-value of 33.1174 and a p-value of 0.0003. The I2 value of 69.80% (95% CI: 25.91% to 92.02%) highlighted the proportion of variability attributed to genuine heterogeneity across the studies. Moreover, the H2 value 3.31 (95% CI: 1.35 to 12.53) indicated significant heterogeneity beyond random chance. The estimated overall effect size (logit-transformed) of 2.1289 was highly statistically significant (z = 8.7648, p < 0.0001) with a confidence interval of 1.6528 to 2.6049. The reported complications varied across studies, encompassing Clavien grade I–II complications in most cases, with a subset experiencing more severe Clavien grade III–V complications. Additionally, other studies noted a range of complications, such as haematuria, fever, transient creatinine elevation, and postoperative issues like bleeding, pain, and sepsis.ConclusionThis meta-analysis suggests that RIRS using TFL is an effective and safe treatment option for renal and ureteral stones, with high stone-free and low complication rates. The included studies exhibited a low risk of bias and were of high quality. However, more extensive randomized controlled trials with extended follow-up periods are needed to investigate this technique's efficacy and safety.

Abstract 15090: Postural Orthostatic Tachycardia Syndrome After COVID-19 Vaccination

Background: COVID-19 vaccination may be associated with postural orthostatic tachycardia syndrome (POTS) incidence, but little is known of who is at risk, their autonomic state, or how they respond to therapy. Methods: This prospective cohort study analyzed clinical data of 10 POTS clinic patients with new-onset or worsening POTS after COVID-19 vaccination. We also compared heart rate variability (HRV, via spot and ambulatory electrocardiograms (ECGs)) and skin sympathetic nerve activation (SKNA) with 24 healthy controls. Results: Patient mean age was 41.5±7.9 years with equal gender balance. Ambulatory ECG showed no major arrhythmias. Mean standing norepinephrine level was 638.2±395.3 pg/mL, with 4 patients &gt;600 pg/mL. All patients had conditions that could raise POTS risk: prior COVID-19 infection (N=4); hypermobile Ehlers-Danlos syndrome (N=6); mast cell activation syndrome (N=3 found pre-POTS, N=3 post-POTS); and autoimmune (N=7), cardiac (N=7), neurologic (N=6), or gastrointestinal conditions (4). HRV analysis indicated lower spot (36.09 ms±49.2) and ambulatory root mean square of successive differences (46.19 ms±24, p=0.042) vs control (72.49 ms±40.8). SKNA showed a reduced mean amplitude (0.97uV±0.052, p=0.011) vs control (1.2 uV±0.31) and burst amplitude (1.67 uV±0.16, p=0.018) vs control (4.3 uV±4.3). All patients received guideline-based POTS care. After 417.2±131.4 days of follow-up, 3 patients were on ivabradine, 2 on beta blockers, 2 on midodrine, 5 on antihistamines, 4 on mast cell stabilizers, and 1 on prednisone. All patients reported improvement, although 2 with COVID-19 reinfection and 1 with small fiber neuropathy did have relapses of POTS symptoms. Conclusion: POTS patients with post-vaccine onset or exacerbation had histories of potential predisposing conditions. These suggest a potential screening approach, though referral bias is possible. Elevated standing norepinephrine levels, decreased HRV, and decreased pRR50 support a sympathetic-dominant state. Though only 2/10 patients stayed on beta blockers, 8/10 did at least transiently use them. Reduced average SKNA and burst-to-mean amplitude ratio suggest the presence of peripheral autonomic neuropathy. Patients responded to standard POTS therapy.

Peripheral Pain Captured Centrally: Altered Brain Morphology on MRI in Small Fiber Neuropathy Patients With and Without an SCN9A Gene Variant

The current study aims to characterize brain morphology of pain as reported by small fiber neuropathy (SFN) patients with or without a gain-of-function variant involving the SCN9A gene and compare these with findings in healthy controls without pain. The Neuropathic Pain Scale was used in patients with idiopathic SFN (N = 20) and SCN9A-associated SFN (N = 12) to capture pain phenotype. T1-weighted, structural magnetic resonance imaging (MRI) data were collected in patients and healthy controls (N = 21) to 1) compare cortical thickness and subcortical volumes and 2) quantify the association between severity, quality, and duration of pain with morphological properties. SCN9A-associated SFN patients showed significant (P < .017, Bonferroni corrected) higher cortical thickness in sensorimotor regions, compared to idiopathic SFN patients, while lower cortical thickness was found in more functionally diverse regions (eg, posterior cingulate cortex). SFN patient groups combined demonstrated a significant (Spearman’s ρ = .44–.55, P = .005–.049) correlation among itch sensations (Neuropathic Pain Scale-7) and thickness of the left precentral gyrus, and midcingulate cortices. Significant associations were found between thalamic volumes and duration of pain (left: ρ = −.37, P = .043; right: ρ = −.40, P = .025). No associations were found between morphological properties and other pain qualities. In conclusion, in SCN9A-associated SFN, profound morphological alterations anchored within the pain matrix are present. The association between itch sensations of pain and sensorimotor and midcingulate structures provides a novel basis for further examining neurobiological underpinnings of itch in SFN. PerspectiveCortical thickness and subcortical volume alterations in SFN patients were found in pain hubs, more profound in SCN9A-associated neuropathy, and correlated with itch and durations of pain. These findings contribute to our understanding of the pathophysiological pathways underlying chronic neuropathic pain and symptoms of itch in SFN.

Comparative Study of Various Fibers in Concrete Subjected to Elevated Temperatures

In this paper fiber reinforced concrete is a two-phase material consisting of a matrix which is reinforced with randomly oriented small diameter fibers to improve the mechanical properties of the matrix. It increases the tensile strength of the concrete. Two types of fibers have been used in this paper i.e steel fiber and glass fiber. Steel fiber reinforced concrete is a homogeneous distribution of randomly oriented discontinuous and discrete steel fibers. It is available in the forms of Carbon steel or stainless steel. It has a high tensile and compressive strength. The Glass fibers are formed by drawing the molten material rapidly from a melted batch in a crucible or furnace. Glass fibers do not have a negative effect on the well-known high compressive strength of concrete. Thus, it shows that the fiber reinforced concrete is in good workable condition rather than without super plasticizer. The addition of 2% steel fiber and 0.5% -1% of glass fiber in concrete is found to be optimum as well as effective and economical as it gives good compression, tensile, and flexural strength for the concrete. Carbon fiber is composed of carbon atoms bonded together to form a long chain. The fibers are extremely stiff, strong, and light, and are used in many processes to create excellent building materials. Carbon fiber material comes in a variety of "raw" building-blocks, including yarns, uni-directional, weaves, braids, and several others, which are in turn used to create composite parts. The properties of a carbon fiber part are close to that of steel and the weight is close to that of plastic. Thus, the strength to weight of a carbon fiber part is much higher than either steel or plastic (Polyvinyl alcohol) (PVA) is well known as a synthetic biodegradable polymer and possesses excellent mechanical properties. PVA “displays strong interaction with carbon nanotubes” (CNTs), resulting in exceptional properties that are not found in another polymer

Effects of Nandrolone Decanoate on Skeletal Muscle and Neuromuscular Junction of Sedentary and Exercised Rats.

Background and Objectives: Nandrolone decanoate (ND) is the most widely used among the anabolic androgenic steroids (AAS), synthetic substances derived from testosterone, to improve muscular and health gains associated with exercises. The AAS leads to physical performance enhancement and presents anti-aging properties, but its abuse is associated with several adverse effects. Supraphysiological doses of AAS with or without physical exercise can cause morphological and functional alterations in neuromuscular interactions. This study aims to investigate the effects of ND supraphysiological doses in neuromuscular interactions, focusing on the soleus muscle and its neuromuscular junctions (NMJs) in rats, associated or not with physical exercise. Materials and Methods: Forty male Sprague Dawley rats were divided into four groups: sedentary and exercised groups, with or without ND at the dose of 10 mg/kg/week. The animals were treated for eight weeks, with intramuscular injections, and the soleus muscle was collected for morphological analyses. Results: The supraphysiological doses of ND in the sedentary group caused muscle degeneration, evidenced by splitting fibers, clusters of small fibers, irregular myofibrils, altered sarcomeres, an increase in collagen deposition and in the number of type I muscle fibers (slow-twitch) and central nuclei, as well as a decrease in fibers with peripheral nuclei. On the other hand, in the ND exercise group, there was an increase in the NMJs diameter with scattering of its acetylcholine receptors, although no major morphological changes were found in the skeletal muscle. Thus, the alterations caused by ND in sedentary rats were partially reversed by physical exercise. Conclusions: The supraphysiological ND exposure in the sedentary rats promoted an increase in muscle oxidative pattern and adverse morphological alterations in skeletal muscle, resulting from damage or post-injury regeneration. In the ND-exercised rats, no major morphological changes were found. Thus, the physical exercise partially reversed the alterations caused by ND in sedentary rats.

Validation of the Body Scan®, a new device to detect small fiber neuropathy by assessment of the sudomotor function: agreement with the Sudoscan®.

Sudomotor dysfunction is one of the earliest manifestations of small fiber neuropathy (SFN), reflecting the alteration of sympathetic C fiber innervation of the sweat glands. Among other techniques, such innervation can be assessed by measuring electrochemical skin conductance (ESC) in microsiemens (μS). In this study, ESC was measured at the feet to detect distal SFN. For this objective, the performance of a new device, the Body Scan® (Withings, France), intended for home use, was compared with that of a reference device, the Sudoscan® (Impeto Medical, France), which requires a hospital setting. In patients with diabetes with or without neuropathy or non-diabetic patients with lower-limb neuropathy, the diagnostic performance of the Body Scan® measurement was assessed by calculating its sensitivity (Se) and specificity (Sp) to detect at least moderate SFN (Se70 and Sp70), defined by a value of feet ESC ≤ 70 μS and > 50 μS on the Sudoscan® measure, or severe SFN (Se50 and Sp50), defined by a value of feet ESC ≤ 50 μS on the Sudoscan® measure. The agreement between the two devices was assessed with the analysis of Bland-Altman plots, mean absolute error (MAE), and root mean squared error (RMSE) calculations. The repeatability of the measurements was also compared between the two devices. A total of 147 patients (52% men, mean age 59 years old, 76% diabetic) were included in the analysis. The sensitivity and specificity to detect at least moderate or severe SFN were: Se70 = 0.91 ([0.83, 0.96]), Sp70 = 0.97 ([0.88, 0.99]), Se50 = 0.91 ([0.80, 0.98]), and Sp50 = 0.99 ([0.94, 1]), respectively. The bias and 95% limits of agreement were 1.5 [-5.4, 8.4]. The MAE was 2.9 and the RMSE 3.8. The intra-sample variability was 2.0 for the Body Scan® and 2.3 for the Sudoscan®. The ESC measurements provided by the Body Scan® were in almost perfect agreement with those provided by the reference device, the Sudoscan®, which validates the accuracy of the Body Scan® for the detection of SFN. By enabling simple, rapid, and autonomous use by the patient at home, this new technique will facilitate screening and monitoring of SFN in daily practice. ClinicalTrials.gov, identifier NCT05178459.

Sensory phenotypes of chronic pain in critically ill patients: a prospective observational study

INTRODUCTION: Determining sensory phenotypes that reflect underlying pain mechanisms may be relevant for critically ill patients with chronic pain. OBJECTIVE: To evaluate the intensity, localization and sensory phenotypes of chronic pain in critically ill patients. MATERIALS AND METHODS: The study included 99 critically ill patients. Inclusion criteria: age 18–75 years, length of stay in the ICU &gt; 3 days, duration of mechanical ventilation &gt; 48 hours, APACHE II score ≥ 7 points, obtaining informed consent. Localization, intensity, and qualitative characteristics of long-term (at least 6 months) pain associated with ICU stay were assessed using the Brief Pain Inventory and the PainDetect Questionnaire, and the severity of anxiety and depression on the HADS scale. Before discharge, all patients underwent thermal quantitative sensory testing (CST) with assessment of cold detection thresholds and warm detection thresholds, paradoxical thermal sensations, cold pain thresholds and heat pain thresholds, conditioned pain modulation. RESULTS: After 6 months chronic pain syndrome developed in 59 % of patients. Data were obtained on the intensity, localization, and severity of the neuropathic and dysfunctional components of pain. When assessing the thermal parameters of QST, a statistically significant difference in the distribution of values for the thresholds of sensitivity to cold and heat was obtained between the group of patients with chronic pain and the group without pain (p &lt; 0.0001) Hierarchical cluster analysis revealed a statistically significant relationship between changes in static and dynamic parameters of thermal sensory testing, the formation of an “irritated” and “deafferent” sensory phenotype depending on the duration of mechanical ventilation, stay in the ICU and assessment on the SOFA scale. CONCLUSIONS: sensory phenotypes make it possible to identify patients with dysfunction of small diameter fibers, impaired endogenous pain control mechanisms, which will allow selecting an individual program to pain relief.

MTHFR mutation: Another unifying etiology of chronic overlapping pain conditions

Introduction and Objective:Chronic pelvic pain (CPP) is a heterogeneous condition with multiple etiologies. Better characterization and understanding of CPP will lead to new therapeutic options and individualization of care, especially in patients with chronic overlapping pain syndromes (COPCs), which increase complexity of diagnosis. In this study, we present 6 patients with COPC and complex CPP, non-focal exam, who tested negative for small fiber neuropathy but who reported a history of methylenetetrahydrofolate reductase (MTHFR) mutations, and retrospective review of 76 patients with MTHFR mutation. This study explores through literature review whether MTHFR mutations play a role in the pathogenesis of chronic pelvic pain and overlapping pain conditions in a subset of patients with COPCs. Methods:Study design included an observational study of 6 patients, a retrospective cross-sectional study of 76 patients, and a literature review. Patients at our institution who tested positive for MTHFR mutations were included in the study; most had been seen in the cardiology/hematology clinics due to the association of MTHFR with clotting disorders. Chart review was performed to identify the presence of pain syndromes and specifically CPP. A review of the literature was undertaken to form a hypothesis for mechanisms that could explain the association between MTHFR mutations and chronic overlapping pain syndromes. Results:Of 76 patients with MTHFR mutations seen primarily in non-pain focused cardiology visits, 30 (39%) had some form of pain syndrome documented, 11 of whom (14%) specifically had CPP. The review below suggests that MTHFR plays a role in the maintenance of nerve tissue and conductance, neural tube defects, and paresthesia. Literature review revealed that MTHFR mutations have been linked with chronic pain and pathological processes such as chronic migraine, interstitial cystitis/bladder pain syndrome, sequelae of chronic Lyme disease, and fibromyalgia. Conclusions:The etiology of chronic pelvic pain is complex. Multisystem pain extending beyond the pelvis complicates the differential diagnosis but suggests a systemic cause. MTHFR mutations may play a unifying role in a subset of chronic pelvic pain patients with concomitant chronic overlapping pain syndromes. The mutations may affect folate metabolism pathways in these patients and hinder the ability to maintain nerve fibers over time, leading to dereliction of pain signal conduction. Disturbance of these pathways may have a role in chronic overlapping pain syndromes and complex pelvic pain.

Amyloid detection and typing yield of skin biopsy in systemic amyloidosis and polyneuropathy.

Disease-modifying therapies are available for amyloidosis but are ineffective if end-organ damage is severe. As small fiber neuropathy is an early and common feature of amyloidosis, we assessed detection and typing yield of skin biopsy for amyloid in patients with confirmed systemic amyloidosis and neuropathic symptoms. In this case-control study, patients with transthyretin and light chain amyloidosis (ATTRv, ATTRwt, and AL) were consecutively recruited. They were sex and age-matched to three control groups (1) non-neuropathic controls (NNC), (2) monoclonal gammopathy of undetermined significance (MGUS), and (3) other neuropathic disease controls (ONC). Patients underwent a double 3 mm skin biopsy in proximal and distal leg. Amyloid index and burden, protein typing by immuno-electron microscopy, intraepidermal nerve fiber density, electroneuromyography, and clinical characteristics were analyzed. We studied 15 subjects with confirmed systemic amyloidosis, 20 NNC, 18 MGUS, and 20 ONC. Amyloid was detected in 100% of patients with amyloidosis (87% in ankle and 73% in thigh). It was not detected in any of the control groups. A small fiber neuropathy was encountered in 100% of amyloidosis patients, in 80% of MGUS, and in 78% of ONC. Amyloid burden was higher in ATTRv, followed by AL and ATTRwt. The ultrastructural examination allowed the identification of the precursor protein by immunotyping in most of the cases. Skin biopsy is a minimally invasive test with optimal sensitivity for amyloid. It allows amyloid typing by electron microscope to identify the precursor protein. The diagnostic work up of systemic amyloidosis should include a skin biopsy.

Passive aeroelastic study of large and flexible wind turbine blades for load reduction

In this paper, passive aeroelastic coupling of wind turbine blades for load reduction is realized by introducing bending-twist coupling (BTC) and geometric sweep coupling (GSC). The BTC is implemented by composite fiber off-axis of the blade spar cap, and the GSC is achieved by defining sweep curves of the blade reference axis. To investigate the passive coupling effect and load reduction of the large and flexible blades, the IEA 15 MW blades are considered. BTC are introduced into the three-dimensional finite element (FE) models and the residual stiffness coefficient is obtained. Meanwhile, geometrically exact beam theory (GEBT) is used to build the flexible blade. Both BTC and GSC are introduced into the beam model, and the effect elastic deformation on blade load is also considered. Multi-objective optimization (MOO) process of rotating blades for load reduction is proposed under steady-state rated conditions. The results show that the highest coupling efficiency can be obtained when the fiber off-axis angle is between 12° and 15°. The BTC of the blade can reduce the load of blade root with a small fiber off-axis angle. Meanwhile, the GSC can further reduce the axis torque. Compared with the initial design of IEA 15 MW steady-state rotating blade, the maximum thrust, flapwise moment and axis torque of the blade can be reduced by 8.8 %, 13.4 % and 22.9 % respectively.

Normal values of sudomotor function assessed by electrochemical skin conductance in African population

BackgroundDysfunction of small nerve fibers remains a major public health concern. Subjects suspected of having small nerve fiber damage need to undergo reliable tests to confirm the diagnosis. Sudomotor function test is a reliable noninvasive exploration for detecting peripheral neuropathies. Nevertheless, the normal reference values derived from the sudomotor function test are not known in the African population. The objective of this study was therefore to describe the normal values of Electrochemical Skin Conductance (ESC) measured by the sudomotor function test in healthy African subjects. Materials and methodsBetween December 1st, 2021 and May 31st, 2022, ESC was measured in 475 healthy subjects (median age: 42 [31–53] years, 46% men) using a sudomotor function test, in the hands and feet. Investigators proposed the examination and received participants’ consent; demographic, anthropometric, biological, and clinical data were obtained before the test. Data on 475 healthy study participants who underwent sudomotor function testing was collected and analyzed. The sociodemographic (age, sex), anthropometric (weight, height, waist circumference, body mass index), diastolic blood pressure, systolic blood pressure, heart rate, and electrochemical skin conductances of the hands and feet were assessed. ResultsESC values were statistically higher in men compared to women (right hand ESC: 70 [60–78] versus 63 [53–72], left hand ESC: 72 [61–80] versus 68 [57–75], right foot ESC: 77 [82–99] versus 72 [64–79], ESC left foot: 76 [68–82] versus 72 [62–78] respectively). ESC values were significantly inversely correlated with age (right hand ESC: r=−0.12, P=0.006; left hand ESC: r=−0.11, P=0.01; right foot ESC: r=−0.37, P<0.0001; ESC left foot: r=−0.38, P<0.0001). ESC values measured in feet were significantly inversely correlated with body mass index (right foot r=−0.22, P<0.0001; left foot r=−0.21, P<0.0001). ConclusionThis study reports normal reference values for ESCs according to age and gender in the healthy African population. Progressive decrease in ESC with aging is confirmed by our data. The value of ESC seems lower in the African population than in other reported ethnicities. This finding needs to be further explored in additional studies.

Fellows research article: use of scrambler therapy to treat small fiber neuropathy.

Fellows research article: use of scrambler therapy to treat small fiber neuropathy.

Cross-sectional study investigating the association between inflammatory biomarkers and neuropathy in adolescents with type 1 diabetes

ObjectivesThe aims of this study were to investigate circulating levels of inflammatory markers in adolescents with type 1 diabetes with and without different types of neuropathies and evaluate the association...

Diabetic Neuropathies.

This article provides an up-to-date review of the diagnosis and management of the most common neuropathies that occur in patients with diabetes. The prevalence of diabetes continues to grow worldwide and, as a result, the burden of diabetic neuropathies is also increasing. Most diabetic neuropathies are caused by hyperglycemic effects on small and large fiber nerves, and glycemic control in individuals with type 1 diabetes reduces neuropathy prevalence. However, among people with type 2 diabetes, additional factors, particularly metabolic syndrome components, play a role and should be addressed. Although length-dependent distal symmetric polyneuropathy is the most common form of neuropathy, autonomic syndromes, particularly cardiovascular autonomic neuropathy, are associated with increased mortality, whereas lumbosacral radiculoplexus neuropathy and treatment-induced neuropathy cause substantial morbidity. Recent evidence-based guidelines have updated the recommended treatment options to manage pain associated with distal symmetric polyneuropathy of diabetes. Identifying and appropriately diagnosing the neuropathies of diabetes is key to preventing progression. Until better disease-modifying therapies are identified, management remains focused on diabetes and metabolic risk factor control and pain management.

Use of fibre reinforced polymer (FRP) in new construction and in strengthening of existing structures

Concrete is the primary construction material for most building projects today owing to its versatility, moldability and superior strength in compression. Concrete however is an inherently brittle material with quite poor tensile strength and has very low resistance to cracks and their propagation throughout the medium. In this research paper, a thorough compilation of previous work on the development of FRPs, their performance under various conditions through traditional structural loading techniques such as 4-point loading and their implementation is provided. Fibre reinforced polymers (FRP) allow alterations in concrete’s structural behaviour under tensile loading as well as expansions during exposures to extreme temperatures and routine shrinkage cracks through addition of small fibres that act as anchors preventing the widening of cracks as well as behaving in a similar fashion to the conventional steel reinforcement. FRP not only comes from small hair like fibres but also in the form of wraps which provide confinement on beams and columns increasing the compressive strength of the element as well as reducing the tensile loads, similar to how prestressing tendons alter the behaviour of prestressed concrete.

Effects of Moderate Exercise Training on Cancer-Induced Muscle Wasting.

Muscle wasting is a common phenomenon in oncology and seems to be attenuated by exercise training. The aim of this study is to determine the degree of aggressiveness of cancer-induced muscle wasting in two different phenotypic muscles. It will also determine whether exercise training can attenuate this muscle dysfunction. Fifty Sprague Dawley rats were randomly assigned to four experimental groups: two breast cancer model groups (sedentary and exercise) and two control groups (sedentary and exercise). Breast cancer was induced by 1-methyl-1-nitrosoureia (MNU). After 35 weeks of endurance training, animals were sacrificed, and gastrocnemius and soleus muscles harvested for morphometric analysis. In sedentary tumor-bearing animals, a significant reduction in cross-sectional area was found in both muscles (p < 0.05). Interstitial fibrosis was significantly higher in the gastrocnemius muscle of the sedentary tumor-bearing animals (p < 0.05), but not in the soleus muscle. In the gastrocnemius of sedentary tumor-bearing animals, a shift from large to small fibers was observed. This cancer-related muscle dysfunction was prevented by long-term exercise training. In sedentary animals with tumors, the gastrocnemius muscle showed a very pronounced reduction in cross-sectional area and a marked degree of interstitial fibrosis. There was no difference in collagen deposition between tumor groups, and the soleus muscle showed a less pronounced but significant reduction in cross-sectional area. These contrasting results confirm that cancer-induced muscle wasting can affect specific types of fibers and specific muscles, namely fast glycolytic muscles, and that exercise training can be used to improve it.

Impact of size and shape in the transport of microplastics by a springtail species

ABSTRACT We investigated the impact of shape (beads, fibers and films) and size (0.5 and 1.0 mm; diameter or length) of polypropylene microplastics (MPs) on MP transport by a springtail species, Folsomia candida in dishes. The percentages of transported beads, fibers and films were 9.10%, 3.18% and 4.10%, respectively. For 1.0 mm MPs, the number of MPs transported was significantly higher for beads than for fibers and films, whereas, for 0.5 mm MPs, the number was significantly higher for fibers than for the other MP types. Additionally, the number of MPs transported was higher for small fibers than for large fibers, whereas it was higher for large beads than for small beads. These results indicate that the effects of F. candida on MP migration depend on MP shape and size. Our results highlight the importance of considering the physical characteristics of MPs while elucidating the interaction between soil fauna and MPs.