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Introduction: Hereditary myopathies arise due to numerous pathogenic variants occurring in distinct genes, which amount to several hundred. Limb-girdle muscular dystrophies (LGMDs) constitute a heterogeneous group of neuromuscular disorders involving more than 30 genes. Clinically, LGMD is characterized by limb-girdle muscular weakness (LGMW). Late-onset Pompe disease is an important disorder with a differential diagnosis for LGMD, where next-generation sequencing (NGS) plays a crucial role in accurate and prompt diagnosis. The sensitivity and specificity of a 10-gene NGS panel have been previously evaluated for the prevalent forms of recessive LGMD (LGMD-R) and Pompe disease in Latin American patients with LGMW of unknown cause. This project aims to identify the regional relative prevalence of frequent LGMD-R subtypes and Pompe disease in a larger geographic area and to diagnose patients with LGMW by identifying genetic variants of LGMD-R and Pompe disease., Methods and Results: This 21-country multicentric analysis enrolled 2,372 patients with LGMW from 2017 to 2018. Sequencing analysis was performed using the Illumina NextSeq 500 system, and variant interpretation was performed according to the American College of Medical Genetics and Genomics guidelines. Pathogenic or likely pathogenic variants were seen in 11% of patients (n = 261). Among the positive cases, NGS effectively diagnosed 86.2% and 13.8% of patients with LGMD and Pompe disease, respectively. The most prevalent pathogenic acid α-glucosidase ( GAA) variant identified was c.-32-13T > G., Conclusion: The study adds to the knowledge of the relative occurrence of various subtypes of LGMD worldwide. The inclusion of GAA in the NGS panel to investigate patients with LGMW is a powerful diagnostic approach to screen for late-onset Pompe disease., Competing Interests: JAB, AMA, AAM, AAF, HD, JC, AA, PS, SSN, SV, and RA have received advisory board honoraria from Sanofi. JAB has received travel support and lecture and speaker honoraria from Sanofi. MGR has nothing to disclose. AF, RA, NT, and ND are employees of Sanofi and hold shares and stock options. The funder had the following involvement in the study: logistic support and editorial assistance for the development of this manuscript., (Copyright © 2024 Bevilacqua, Al-Salti, Al Madani, Alves da Fonseca, Durmus, Chai, Alshehri, Ribeiro, Sgobbi, Nikitin, Vargas, Furtado, Thibault, Araujo and Daba.)

Background: Dysferlinopathy is a phenotypically heterogeneous group of hereditary diseases caused by mutations in the DYSF gene. Early contractures are considered rare, and rigid spine syndrome in dysferlinopathy has been previously reported only once., Case Presentation: We describe a 23-year-old patient with Miyoshi myopathy with a rigid spine and multiple contractures, a rare phenotypic variant. The disease first manifested when the patient was 13 years old, with fatigue of the gastrocnemius muscles and the development of pronounced contractures of the Achilles tendons, flexors of the fingers, and extensors of the toes, followed by the involvement of large joints and the spine. Magnetic resonance imaging revealed signs of connective tissue and fatty replacement of the posterior muscles of the thighs and lower legs. Edema was noted in the anterior and medial muscle groups of the thighs, lower legs, and the multifidus muscle of the back. Whole genome sequencing revealed previously described mutations in the DYSF gene in exon 39 (c.4282 C > T) and intron 51 (c.5785-824 C > T). An immunohistochemical analysis and Western blot showed the complete absence of dysferlin protein expression in the muscle fibers., Conclusions: This case expands the range of clinical and phenotypic correlations of dysferlinopathy and complements the diagnostic search for spine rigidity., (© 2024. The Author(s).)

The oxygen content was measured in cubic perovskite-type La 1/3 Sr 2/3 Fe 1- x Mn x O 3- δ ( x = 0.1, 0.17, 0.25, and 1/3) in the range of oxygen partial pressure from 10 -22 to 0.5 atm at 750-950 °C with a step of 50 °C by coulometric titration. Gradual removal of oxygen from the oxides during the measurements was carried out until the stability limit was achieved and the reductive decomposition began. An increase in manganese content was shown to lead to a decrease in the stability of La 1/3 Sr 2/3 Fe 1- x Mn x O 3- δ under reducing conditions. The obtained data on oxygen content were used for defect chemistry modeling in the oxides. The enthalpy of the Fe 3+ to Fe 4+ and Mn 3+ to Mn 4+ oxidation reactions (Δ H ox 0 ) was determined to be -103.2 ± 0.3 and -250 ± 2 kJ mol -1 , respectively, for the x = 0.1 composition, and increased slightly with increasing manganese content. The large difference in Δ H ox 0 determines a strong distinction between the behavior of iron and manganese in perovskite-type oxides. An increase in manganese content in La 1/3 Sr 2/3 Fe 1- x Mn x O 3 -δ was found to lead to a decrease in the concentration of Fe 4+ ions, but did not affect the concentration of Fe 2+ ions. The impact of La/Sr ratio was evaluated by comparison of the obtained data with that for La 0.5 Sr 0.5 Fe 1- x Mn x O 3 -δ , and found to be different for iron and manganese. An increase in lanthanum fraction causes a decrease in the concentration of Fe 2+ ions and an increase in the concentration of Mn 2+ under reducing conditions.

The expert consensus is aimed to develop an algorithm for the diagnosis and treatment of mononeuropathies for outpatient neurologists. Leading experts in the field of neurology have suggested workup options for certain types of tunnel mononeuropathies based on current data on the effectiveness and safety of various types of conservative and surgical treatment.

Perovskite-type La 0.5 Sr 0.5 Fe 0.9 Mo 0.1 O 3- δ synthesized via glycine nitrate combustion and sintered at 1350 °C was found to have an orthorhombic lattice, which transforms upon heating into a rhombohedral and then a cubic one. The oxygen content and electrical conductivity in this oxide were measured in the range of oxygen partial pressures from 10 -20 to 0.5 atm at 750-950 °C by coulometric titration and four-probe dc techniques, respectively. The oxygen content data were used to model the defect equilibrium in the oxide. Oxidation, charge disproportionation and electron exchange reactions between iron and molybdenum were assumed by the model to be involved in the formation of defects. The experimental data were well approximated with the model and the concentrations of charge carriers in La 0.5 Sr 0.5 Fe 0.9 Mo 0.1 O 3- δ were determined to be used for the electrical conductivity analysis. The average mobility of oxygen ions and n- and p-type charge carriers was determined to be about 10 -5 , 0.007, and 0.07 cm 2 V -1 s -1 with an activation energy of 0.80 ± 0.02, 0.34 ± 0.01, and 0.23 ± 0.01 eV, respectively. Comparison with La 0.5 Sr 0.5 FeO 3- δ shows that 10% Mo substitution provides a substantial increase in both the concentration and mobility of n-type carriers, which results in an almost threefold increase in electron conductivity under reducing conditions, while maintaining a high level of ionic conductivity.

The structure, oxygen non-stoichiometry, and defect equilibrium in perovskite-type PrBa 1- x Sr x Fe 2 O 6- δ ( x = 0, 0.25, 0.50) synthesized at 1350 °C were studied. For all compositions, X-ray diffraction testifies to the formation of a cubic structure (S.G. Pm3¯m), but an electron diffraction study reveals additional diffuse satellites around each Bragg spot, indicating the primary incommensurate modulation with wave vectors about ±0.43a*. The results were interpreted as a sign of the short-order in both A-cation and anion sublattices in the areas of a few nanometers in size, and of an intermediate state before the formation of an ordered superstructure. An increase in oxygen deficiency was found to promote the ordering, whereas partial substitution of barium by strontium caused the opposite effect. The oxygen content in oxides as a function of oxygen partial pressure and temperature was measured by coulometric titration, and the data were used for the modeling of defect equilibrium in oxides. The simulation results implied oxygen vacancy ordering in PrBa 1- x Sr x Fe 2 O 6- δ that is in agreement with the electron diffraction study. Besides oxidation and charge disproportionation reactions, the reactions of oxygen vacancy distribution between non-equivalent anion positions, and their trapping in clusters with Pr 3+ ions were taken into account by the model. It was demonstrated that an increase in the strontium content in Pr 0.5 Ba 0.5- x Sr x FeO 3- δ suppressed ordering of oxygen vacancies, increased the binding energy of oxygen ions in the oxides, and resulted in an increase in the concentration of p-type carriers.

The article presents the work of a multidisciplinary team of experts from various fields of medicine to optimize the «Questionnaire for assessing chronic pelvic pain and pelvic organ dysfunction (QCPPD) of the Ryzhikh National Medical Research Centre for Coloproctology» for use in clinical practice. The survey of respondents was conducted from June 28 to September 28, 2021. As a result of this survey, by repeatedly making edits and clarifications during communication with respondents, the final version was obtained, which allows assessing the patient's subjective sensations by the nature and localization of pelvic pain, sensitivity disorders and pelvic organ function. The main objective of this Questionnaire is to differentiate patients with neurogenic pain from a huge number of patients with chronic pelvic pain. This aspect will allow a more targeted approach to the diagnosis and pathogenetically justified treatment of patients, including after appropriate instrumental examinations. The work of a multidisciplinary team implies a higher degree of objectification and terminological accuracy of the Questionnaire under discussion. The presented version of the «Questionnaire for assessing chronic pelvic pain and pelvic organ dysfunction (QCPPD) of the Ryzhikh National Medical Research Centre for Coloproctology» will be primarily used in coloproctological patients with pelvic pain problems and anal incontinence and obstructive defecation. Further studies will be directed to the clinical evaluation of the results of the work carried out.

The widespread use of magnetic resonance imaging (MRI) in the diagnosis of myopathies has made it possible to clarify the typical MRI pattern of dysferlinopathy. However, sufficient attention has not been given to the variability of MRI patterns in dysferlinopathy., Materials and Methods: Twenty-five patients with the clinical manifestations of dysferlinopathy were examined. For all patients, creatine phosphokinase levels were measured and molecular genetics were examined. In two patients, immunohistochemical examinations of muscle biopsies were performed. MRI scanning was included T2 multi-slice multi-echo, T1 weighted, T2 weighted and Short Tau Inversion Recovery T2 weighted sequences. Quantitative and semi-quantitative evaluations of fatty replacement and swelling of the muscles were undertaken., Results: Variability in the MRI patterns was lowest in the pelvis and leg muscles and highest in the thigh muscles. Three main types of MRI patterns were distinguished: posterior-dominant (80%), anterior-dominant (16%), and diffuse (4%). Among patients with the anterior-dominant pattern, the collagen-like variant (4%), proximal variant (4%) and pseudo-myositis (8%) were separately distinguished., Conclusions: Awareness of atypical MRI patterns in dysferlinopathy is important for increasing the efficiency of routine diagnostics and optimizing the search for causative gene mutations., (©2021 Gaetano Conte Academy - Mediterranean Society of Myology, Naples, Italy.)

The oxygen content in La 0.5 Sr 0.5 Fe 1- x Mn x O 3- δ , measured by coulometric titration in a wide range of oxygen partial pressure at various temperatures, was used for defect chemistry analysis. The obtained data were well approximated by a model assuming defect formation in La 0.5 Sr 0.5 Fe 1- x Mn x O 3- δ via Fe 3+ and Mn 3+ oxidation reactions and charge disproportionation on Fe 3+ and Mn 3+ ions. The partial molar enthalpy and entropy of oxygen in La 0.5 Sr 0.5 Fe 1- x Mn x O 3- δ obtained by statistical thermodynamic calculations were found to be in satisfactory agreement with those obtained using the Gibbs-Helmholtz equations, thus further confirming the adequacy of the model. The impact of manganese substitution on defect equilibrium in La 0.5 Sr 0.5 Fe 1- x Mn x O 3- δ was shown to be attributed to a lower enthalpy of Mn 3+ oxidation reaction ( vs. for the oxidation of Fe 3+ ) and the charge disproportionation reaction on Mn 3+ ( vs. for that on Fe 3+ ). The former makes Mn 4+ ions more resistant to reduction than Fe 4+ . The latter favors the presence of Mn 2+ , Mn 3+ , and Mn 4+ ions in oxides in comparable concentrations. The distribution of charge carriers over iron and manganese ions was determined as a function of oxygen content in La 0.5 Sr 0.5 Fe 1- x Mn x O 3- δ .

The oxygen content and electrical conductivity in Nd 0.25 Sr 0.75 FeO 3-δ were measured in the range of oxygen partial pressure from 10 -19 to 0.5 atm at 750-950 °C by coulometric titration and four-probe dc techniques. The thermodynamic analysis of defect equilibrium in the oxide allowed successful simulation of the oxygen content data and calculation of charge carrier concentrations that were used for the analysis of electrical conductivity. The electrical conductivity data were accurately described in the models, which implied that the hole mobility increased upon an increase in the oxygen content in the oxide. The results suggest that only some of the Fe 3+ sites are available for hole transport, and their fraction increases with an increase in the oxygen content. The migration energy for oxygen ions, electrons and holes was found to be 0.89 ± 0.02, 0.62 ± 0.01 and 0.230 ± 0.006 eV, respectively. Nd 0.25 Sr 0.75 FeO 3-δ was shown to have a considerable oxygen conductivity (0.12 S cm -1 at 950 °C) and fairly good stability under reducing conditions, which is a good recommendation for using this oxide as a functional material in high-temperature electrochemical applications.

Pathogenic variants in the HINT1 gene lead to hereditary axonopathy with neuromyotonia. However, many studies show that neuromyotonia may remain undiagnosed, while axonopathy is the major clinical finding. The most common cause of neuromyotonia and axonopathy, especially in patients of Slavic origin, is a c.110G>C (p.Arg37Pro) pathogenic variant in homozygous or compound heterozygous state. In this study, we analyzed a peripheral neuropathy caused by pathogenic variants in the HINT1 gene and evaluated its contribution to the hereditary neuropathy structure. The studied group included 1596 non-related families diagnosed with hereditary motor and sensory neuropathy (HMSN). The results show that HINT1 gene pathogenic variants make a significant contribution to the hereditary neuropathy epidemiology in Russian patients. They account for at least 1.9% of all HMSN cases and 9% of axonopathy cases. The most common HINT1 pathogenic variant in Russian patients is the c.110G>C (p.Arg37Pro) substitution. Its allelic frequency is 0.2% (95% CI 0.19-0.21%), carrier frequency is 1 in 250 people in Russian Federation, and the estimated disease incidence is 1 in 234,000 individuals. It was determined that the cause of this pathogenic variant's prevalence is the founder effect.

Objective: To describe clinical and sonographic features of confirmed intraneural perineurioma in 5 patients., Material and Methods: We report clinical and sonographic features and retrospective follow-up data in 5 patients with intraneural perineurioma verified by biopsy., Results: In all cases, symptoms were represented by a slowly progressive painless mononeuropathy with muscle atrophy and impaired tendon reflexes. Ultrasound examination revealed locally enlarged cross-sectional area of the nerve that was confirmed by intraoperative visualization., Conclusion: Intraneural perineurioma should be obligatory suspected in case of fusiform thickening of the nerve with locally changed echogenicity. Pooled multiple-center studies with large samples are needed to determine sensitivity and specificity of the main ultrasound parameters including changes in cross-sectional area and echogenicity of the nerve.

The authors report the clinical case of a 7-year-old child with gradual development in left leg weakness considering by the neurologist as the unknown lesion of the sciatic nerve. According to the results of clinical and instrumental examinations, the diagnosis was established as a focal form of chronic inflammatory demyelinating polyneuropathy (CIDP). The dysimmune cause of the disease was confirmed by MRI of the lumbosacral plexus with contrast enhancement of neural structures and response to therapy with high-dose intravenous immunoglobulin in combination with corticosteroids.

Differential high-resolution ECG (V1-V2) and pelvic electric potential measured between the coccyx and perineum were recorded simultaneously in resting supine position in men with autonomic nervous system disorders (N=37). In healthy volunteers (N=23), the effective (rms) value of PEP presented by median and interdecile range was 30 (20-80) μV within the frequency band of 0.03-80 Hz. In patients, the corresponding value was significantly higher: 140 (80-280) μV. In both groups, the amplitude harmonic spectrum of pelvic electric potential decreased monotonically with frequency according to 1/f1.6 law. In some patients (N=16), rare single or grouped high-amplitude impulses (up to 1 mV) of pelvic electric potential with total duration of about 1 sec were observed; of them, some persons (N=7) demonstrated practically one-to-one synchronous relations between these impulses and arrhythmia episodes indicating abnormal activity of the autonomic nervous system as their most probable common cause. The high-amplitude pelvic electric potential impulses were also observed in ECG records as interference signals with an amplitude attaining 50 μV. Thus, high-resolution ECG and pelvic electric potential can reveal the risk of abnormal neurogenic influences on the heart. The data obtained are discussed in relation to diagnostics of the autonomic nervous system disorders, neurogenic arrhythmias, and risk of sudden cardiac death.

Among many causes of compression neuropathies involving the radial nerve, compression of the posterior interosseous nerve (PIN) by the returning radial arteries is rare., Objective: To describe the clinical instrumental characteristics of cases of mononeuropathy caused by compression of the return radial arteries., Material and Methods: Two observations with neuropathy of the deep branch of the radial nerve, manifested by weakness in the corresponding muscles, inconsistent pain syndrome with previous stereotypic (recurring) physical activity are presented., Results: According to the results of ultrasound examination of posterior interosseous nerve, a local hypoechogenic increase in the cross-sectional area of nerve of different lengths was revealed. During surgical decompression of the nerve, in the first case, a tight arterial loop was found around the nerve, in the second case, expanded arterial trunks, one of which, of small diameter, covered the nerve in the 'loop', and the other, larger, pierced the nerve. After the operation, regression of motor deficiency and relief of pain were noted.

Aim: To describe the sonographic phenomenon of the focal 'hourglass-like constriction' of the peripheral nerves (FCPN)., Material and Methods: The authors described 7 patients meeting the criteria for the diagnosis of neuralgic amyotrophy with unilateral FCPN identified with ultrasound in 4 cases and detected intraoperatively in 3 cases (preliminary ultrasound was not performed). The US scanner Sonoscape Pro mode gray scale in the transverse and longitudinal scanning, linear probe 8-15 MHz and Logiq9 scanner with elastography were used., Results: FCPN was detected in the single nerve in 4 patients, in two nerves in 2 patients and in 3 nerves in one patient. Among all the nerves involved in the pathological process, the radial nerve and its branches were affected in 73% (8 nerves); the ulnar nerve was involved in 18% (2 nerves) and the musculo-cutaneous nerve in 9%. The length of the constriction of the peripheral nerve did not exceed 1.7 mm. The deformation coefficient (DC) of constriction area was 3.8 to .,9; the change in the elasticity in the form of an increase of DC to 5.9 when compared to the intact portion of the nerve and a decrease in echogenicity were observed in one patient., Conclusion: High-resolution ultrasound of the nerve can be an informative method for the diagnosis of idiopathic non-traumatic FCPN mononeuropathy.