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Although extensively studied, the exact nature of Kaposi's sarcoma (KS), the most common tumors in AIDS patients worldwide, is still controversial. KS is a highly vascularised tumor, apparently induced by HHV8 infection of vascular precursors, endothelial cells, circulating endothelial and/or haematopoietic progenitors. Cell lines derived from KS biopsies show similar characteristics: a mixture of mesenchymal and vascular markers. Given the growing interest in cancer stem cells as a new perspective in cancer treatment, we decided to isolate and characterize the potential stem sub-populations in KS cultures and to study whether the interaction of these cells with the microenvironment may influence their tumorigenicity.Two KS cell lines (KS-IMM and SLK), cultured out of biopsy material from KS patients, were used to asses stemness capability of this tumor.KS cells were karyotypically characterized, analyzed by functional genomics with Affymetrix arrays and then grown in specific serum-free stem cell medium. Cell proliferation assay showed an anchorage-independent growth capability of KS and SLK cell lines forming spheroid structures. With increasing passages, these KS-derived spheroids showed an increase in proliferation potential and sphere forming efficiency.Surface expression markers on spheroids were evaluated through flow cytometry and compared to parental cell lines. Consistent increase in CD34 and CD326 and decrease in CD133 and CD144 were found in cells derived from KS-IMM spheroid compared to parental cells, while only ABCG2 is consistently decreased in SLK spheroids. Preliminary results suggest the existence of a KS subpopulation showing stemness features. [ABSTRACT FROM AUTHOR]

Objective: Spinal muscular atrophy (SMA) is a neurodegenerative disorder caused by mutations in the SMN1 gene. The aim of this study was to assess the prevalence of SMA and treatment prescription in Italy., Methods: An online survey was distributed to 36 centers identified by the Italian government as referral centers for SMA. Data on the number of patients with SMA subdivided according to age, type, SMN2 copy number, and treatment were collected., Results: One thousand two hundred fifty-five patients with SMA are currently followed in the Italian centers with an estimated prevalence of 2.12/100,000. Of the 1,255, 284 were type I, 470 type II, 467 type III, and 15 type IV with estimated prevalence of 0.48, 0.79, 0.79 and 0.02/100,000, respectively. Three patients with SMA 0 and 16 presymptomatic patients were also included. Approximately 85% were receiving one of the available treatments. The percentage of treated patients decreased with decreasing severity (SMA I: 95.77%, SMA II: 85.11%, SMA III: 79.01%)., Discussion: The results provide for the first time an estimate of the prevalence of SMA at the national level and the current distribution of patients treated with the available therapeutical options. These data provide a baseline to assess future changes in relation to the evolving therapeutical scenario., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

Introduction: With acclimatization to high altitude (HA), adaptations occur throughout the nervous system and at the level of the muscle, which may affect motor unit (MU) characteristics. However, despite the importance of MUs as the final common pathway for the control of voluntary movement, little is known about their adaptations with acclimatization., Methods: Ten lowlanders and Sherpa participated in this study 7 to 14 d after arrival at HA (5050 m), with seven lowlanders repeating the experiment at sea level (SL), 6 months after the expedition. The maximal compound muscle action potential (M max ) was recorded from relaxed biceps brachii. During isometric elbow flexions at 10% of maximal torque, a needle electrode recorded the MU discharge rate (MUDR) and MU potential (MUP) characteristics of single biceps brachii MUs., Results: Compared with SL, acclimatized lowlanders had ~10% greater MUDR, ~11% longer MUP duration, as well as ~18% lower amplitude and ~6% greater duration of the first phase of the M max (all P < 0.05). No differences were noted between SL and HA for variables related to MUP shape (e.g., jitter, jiggle; P > 0.08). Apart from lower near-fiber MUP area for Sherpa than acclimatized lowlanders ( P < 0.05), no M max or MU data were different between groups ( P > 0.10)., Conclusions: Like other components of the body, MUs in lowlanders adapt with acclimatization to HA. The absence of differences between acclimatized lowlanders and Sherpa suggests that evolutionary adaptations to HA are smaller for MUs than components of the cardiovascular or respiratory systems., (Copyright © 2022 by the American College of Sports Medicine.)

Objective: Systemic lupus erythematosus (SLE) is associated to boosted atherosclerosis development and a higher cardiovascular disease risk. This study aimed to delineate the role of anti-double stranded DNA (anti-dsDNA) antibodies on the molecular profile and the activity of immune and vascular cells, as well as on their enhanced cardiovascular risk., Approach and Results: Eighty SLE patients were included. Extensive clinical/analytical evaluation was performed, including cardiovascular disease parameters (endothelial function, proatherogenic dyslipidemia, and carotid intima-media thickness). Gene and protein expression profiles were evaluated in monocytes from patients diagnosed positive or negative for anti-dsDNA antibodies by using NanoString and cytokine arrays, respectively. NETosis and circulating inflammatory profile was assessed in both neutrophils and plasma. Positivity and persistence of anti-dsDNA antibodies in SLE patients were associated to endothelial dysfunction, proatherogenic dyslipidemia, and accelerated atherosclerosis. In parallel, anti-dsDNA antibodies were linked to the aberrant activation of innate immune cells, so that anti-dsDNA(+) SLE monocytes showed distinctive gene and protein expression/activity profiles, and neutrophils were more prone to suffer NETosis in comparison with anti-dsDNA(−) patients. Anti-dsDNA(+) patients further displayed altered levels of numerous circulating mediators related to inflammation, NETosis, and cardiovascular risk. In vitro, Ig-dsDNA promoted NETosis on neutrophils, apoptosis on monocytes, modulated the expression of inflammation and thrombosis-related molecules, and induced endothelial activation, at least partially, by FcR (Fc receptor)-binding mechanisms., Conclusions: Anti-dsDNA antibodies increase the cardiovascular risk of SLE patients by altering key molecular processes that drive a distinctive and coordinated immune and vascular activation, representing a potential tool in the management of this comorbidity.

Purpose: We investigated the effect of high-altitude acclimatization on peripheral fatigue compared with sea level and acute hypoxia., Methods: At sea level (350 m), acute hypoxia (environmental chamber), and chronic hypoxia (5050 m, 5-9 d) (partial pressure of inspired oxygen = 140, 74 and 76 mm Hg, respectively), 12 participants (11 in chronic hypoxia) had the quadriceps of their dominant leg fatigued by three bouts of 75 intermittent electrically evoked contractions (12 pulses at 15 Hz, 1.6 s between train onsets, and 15 s between bouts). The initial peak force was ~30% of maximal voluntary force. Recovery was assessed by single trains at 1, 2, and 3 min postprotocol. Tissue oxygenation of rectus femoris was recorded by near-infrared spectroscopy., Results: At the end of the fatigue protocol, the impairments of peak force and peak rates of force development and relaxation were greater (all P < 0.05) in acute hypoxia (~51%, 53%, and 64%, respectively) than sea level (~43%, 43%, and 52%) and chronic hypoxia (~38%, 35%, and 48%). Peak force and rate of force development recovered faster (P < 0.05) in chronic hypoxia (pooled data for 1-3 min: ~84% and 74% baseline, respectively) compared with sea level (~73% and 63% baseline) and acute hypoxia (~70% and 55% baseline). Tissue oxygenation did not differ among conditions for fatigue or recovery (P > 0.05)., Conclusions: Muscle adaptations occurring with chronic hypoxia, independent of other adaptations, positively influence muscle contractility during and after repeated contractions at high altitude.

Purpose: At high altitude, Lowlanders exhibit exacerbated fatigue and impaired performance. Conversely, Sherpa (native Highlanders) are known for their outstanding performance at altitude. Presently, there are no reports comparing neuromuscular fatigue and its etiology between Lowlanders and Sherpa at altitude., Methods: At 5050 m, nine age-matched Lowlanders and Sherpa (31 ± 10 vs 30 ± 12 yr, respectively) completed a 4-min sustained isometric elbow flexion at 25% maximal voluntary contraction (MVC) torque. Mid-minute, stimuli were applied to the motor cortex and brachial plexus to elicit a motor-evoked potential and maximal compound muscle action potential (Mmax), respectively. Supraspinal fatigue was assessed as the reduction in cortical voluntary activation (cVA) from prefatigue to postfatigue. Cerebral hemoglobin concentrations and tissue oxygenation index (TOI) were measured over the prefrontal cortex by near-infrared spectroscopy., Results: Prefatigue, MVC torque, and cVA were significantly greater for Lowlanders than Sherpa (79.5 ± 3.6 vs 50.1 ± 11.3 N·m, and 95.4% ± 2.7% vs 88.2% ± 6.6%, respectively). With fatigue, MVC torque and cVA declined similarly for both groups (~24%-26% and ~5%-7%, respectively). During the task, motor-evoked potential area increased more and sooner for Lowlanders (1.5 min) than Sherpa (3.5 min). The Mmax area was lower than baseline throughout fatigue for Lowlanders but unchanged for Sherpa. TOI increased earlier for Lowlanders (2 min) than Sherpa (4 min). Total hemoglobin increased only for Lowlanders (2 min). Mmax was lower, whereas TOI and total hemoglobin were higher for Lowlanders than Sherpa during the second half of the protocol., Conclusions: Although neither MVC torque loss nor development of supraspinal fatigue was different between groups, neural-evoked responses and cerebral oxygenation indices were less perturbed in Sherpa. This represents an advantage for maintenance of homeostasis, presumably due to bequeathed genotype and long-term altitude adaptations.

Purpose of Review: Muscle pain syndromes are extremely frequent cause of chronic disability, and a muscle biopsy is often performed to achieve a diagnosis when myalgia has a myopatic origin. Instead, the role of muscle biopsy in fibromyalgia is controversial. This review examines the reported studies with the objective to evaluate if some changes exist in the muscle, if these changes produce pain and if muscle biopsy is helpful in diagnostic flowchart of fibromyalgia., Recent Findings: Recent studies focused on functional side (muscle metabolism and the altered expression of proteins) hypothesize the role of peripheral factors in the maintenance of chronic pain. The results of some studies show the increased concentration of the end products of anaerobic glycolysis and a damage in oxidative metabolism caused by localized hypoxia. In addition, it is present as an insufficient capacity of promoting muscle recovery with inflammation and in metabolic pathway alterations. Unfortunately, these changes are nonspecific and the importance of peripheral factors remains under debate., Summary: Morphological and metabolic changes exist in muscle of patients with fibromyalgia but they are not specific and are not sufficient for a definite diagnosis. Nevertheless, the results obtained so far indicate a role of peripheral factors for maintaining the intensity of pain. Therefore, it is desirable to have a better understanding of peripheral muscle alteration that could open up for new therapeutic strategies.

Introduction: The knee and ankle extensors as human primary antigravity muscle groups are of utmost importance in a wide range of locomotor activities. Yet, we know surprisingly little about how these muscle groups work, and specifically, how close to their maximal capacities they function across different modes and intensity of locomotion. Therefore, to advance our understanding of locomotor constraints, we determined and compared relative operating efforts of the knee and ankle extensors during walking, running, and sprinting., Methods: Using an inverse dynamics biomechanical analysis, the muscle forces of the knee and ankle extensors during walking (1.6 m·s), running (4.1 m·s), and sprinting (9.3 m·s) were quantified and then related to maximum forces of the same muscle groups obtained from a reference hopping test that permitted natural elastic limb behavior., Results: During walking, the relative effort of the ankle extensors was almost two times greater compared with the knee extensors (35% ± 6% vs 19% ± 5%, P < 0.001). Changing walking to running decreased the difference in the relative effort between the extensor muscle groups, but still, the ankle extensors operated at a 25% greater level than the knee extensors (84% ± 12% vs 63% ± 17%, P < 0.05). At top speed sprinting, the ankle extensors reached their maximum operating level, whereas the knee extensors still worked well below their limits, showing a 25% lower relative effort compared with the ankle extensors (96% ± 11% vs 72% ± 19%, P < 0.01)., Conclusions: Regardless of the mode of locomotion, humans operate at a much greater relative effort at the ankle than knee extensor muscles. As a consequence, the great demand on ankle extensors may be a key biomechanical factor limiting our locomotor ability and influencing the way we locomote and adapt to accommodate compromised neuromuscular system function.

Objective: To apply next-generation sequencing (NGS) for the investigation of the genetic basis of undiagnosed muscular dystrophies and myopathies in a very large cohort of patients., Methods: We applied an NGS-based platform named MotorPlex to our diagnostic workflow to test muscle disease genes with a high sensitivity and specificity for small DNA variants. We analyzed 504 undiagnosed patients mostly referred as being affected by limb-girdle muscular dystrophy or congenital myopathy., Results: MotorPlex provided a complete molecular diagnosis in 218 cases (43.3%). A further 160 patients (31.7%) showed as yet unproven candidate variants. Pathogenic variants were found in 47 of 93 genes, and in more than 30% of cases, the phenotype was nonconventional, broadening the spectrum of disease presentation in at least 10 genes., Conclusions: Our large DNA study of patients with undiagnosed myopathy is an example of the ongoing revolution in molecular diagnostics, highlighting the advantages in using NGS as a first-tier approach for heterogeneous genetic conditions., (© 2016 American Academy of Neurology.)

Objective: Tobacco smoke (TS) interacts with inflammatory cytokines to produce endothelial dysfunction. We hypothesized that interleukin-1beta (IL-1beta) plus TS (TS/IL-1beta) induces disassembly of endothelial junctional complexes of VE-cadherin/beta-catenin by suppression of PTEN activity and investigated molecular mechanisms that modulate PTEN-deactivation in this situation., Methods and Results: TS/IL-1beta exposure, which disrupted adherens junctions and induced nuclear beta-catenin accumulation, increased tyrosine phosphorylation (p-Tyr) of VE-cadherin and beta-catenin, and reduced PTEN activity. Overexpression or silencing of PTEN modulated p-Tyr of both VE-cadherin and beta-catenin, changed assembly of adherens junction complexes, and altered nuclear beta-catenin accumulation. In addition, inhibiting ROS production stimulated by TS/IL-1beta decreased activation of Src, EGFR and p38MAPK, phosphorylation of PTEN, VE-cadherin and beta-catenin, and abrogated the effect of TS/IL-1beta to disorganize adherens junctions, resulting in reduced endothelial permeability and decreased nuclear beta-catenin accumulation. Finally, exposure of ApoE(-/-) mice to cigarette smoke-induced phosphorylation of Src, EGFR, p-38MAPK, PTEN, and beta-catenin, and disrupted VE-cadherin/beta-catenin complexes in cardiovascular tissue., Conclusions: TS interaction with IL-1beta modulates PTEN activity though the ROS/Src/EGFR-p38MAPK pathway. PTEN deactivation is essential to increase VE-cadherin and beta-catenin p-Tyr and to disassemble VE-cadherin/beta-catenin membrane complexes, events that lead to accumulation of beta-catenin within the nucleus.

Unlabelled: In this study we evaluated whether a technology based on artificial neural networks (ANN) could estimate the static compliance (C(RS)) of the respiratory system, even in the absence of an end-inspiratory pause, during continuous mechanical ventilation. A porcine model of acute lung injury was used to provide recordings of different respiratory mechanics conditions. Each recording consisted of 10 or more consecutive breaths in volume-controlled mechanical ventilation, followed by a breath having an end-inspiratory pause used to calculate C(RS) according to the interrupter technique (IT). The volume-pressure loop of the breath immediately preceding the one with pause was given to the ANN for the training, together with the C(RS) separately calculated by the IT. The prospective phase consisted of giving only the loops to the trained ANN and comparing the results yielded by it to the compliance separately calculated by the investigators. Determination of measurement agreement between ANN and IT methods showed an error of -0.67 +/- 1.52 mL/cm H(2)O (bias +/- SD). We could conclude that ANN, during volume-controlled mechanical ventilation, can extract C(RS) without needing to stop inspiratory flow., Implications: We studied the application of artificial neural networks (ANN) to the estimation of respiratory compliance during mechanical ventilation. The study was performed on an animal model of acute lung injury, testing the performance of ANN in both healthy and diseased conditions of the lung.

The psychological impact of the diagnosis of gestational diabetes was examined in 68 pregnant women. No differences between the women with gestational diabetes and 50 non-diabetic pregnant controls, matched for gestational age, were found on the Profile of Mood States--Bipolar Form. Contrary to clinical lore, the prescription of insulin was not found to have an adverse effect on the emotional status of women with gestational diabetes. In this diabetic population whose blood glucose levels were well controlled, psychological status was not found to be related to blood glucose levels. The results suggest that the majority of pregnant women adapt readily to the unexpected diagnosis of gestational diabetes.