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Sjogren’s disease (SjD) is a chronic and disabling autoimmune disease, predominantly characterized by dryness of the mouth and eyes, resulting from lymphocytic infiltration of exocrine glands. While these are the most prominent symptoms, extra-glandular manifestations are also common. Studies suggest that up to 70% of SjD patients experience neurological symptoms, which interestingly often precede the hallmark dryness. Although every structure of the nervous system can be affected, disorders of peripheral nervous system (PNS) are more common than central nervous system (CNS) involvement. The CNS manifestations can range from subtle to severe, with some patients experiencing a rapid progression of symptoms. The literature documents cases where patients initially diagnosed with Creutzfeldt-Jakob disease, neurosarcoidosis, temporary hemiplegia, neuromyelitis optica, or epilepsy were ultimately diagnosed as having SjD. Here, we present five SjD patient cases, each with a different manifestation of CNS involvement, along with an overview of the current understanding of CNS disorders in the course of the disease. In four cases, the neurological manifestations appeared before the onset of sicca symptoms. In one patient, diagnosis was delayed by 15 years due to an atypical presentation. After receiving immunosuppression, all patients experienced notable alleviation of their symptoms. [ABSTRACT FROM AUTHOR]

Introduction: Sjögren's syndrome (SS) is a chronic autoimmune disease characterized by lymphocytic infiltrates in the exocrine glands. Carpal tunnel syndrome (CTS) is suggested to be more frequent among SS patients than in the general population. The aim of this study was to seek associations between the CTS and the laboratory and clinical findings of SS patients. Methods: Fifty patients diagnosed with primary SS (pSS) were examined. Clinical evaluation by a rheumatologist and electrophysiological studies were conducted. Data on laboratory tests results was collected. Control group consisted of 50 sex and age-matched individuals with osteoarthritis (OA). Results: Out of 50 patients in the study group 27 (54%) were diagnosed with CTS. The prevalence of CTS among 50 individuals in the control group was 8%. Among pSS patients with CTS the joint involvement was not more common than in those from the non-CTS group [15 vs. 13 (p = 0.945)]. There was an expected difference in sleep disorders [18 vs. 9 (p = 0.012)] and paresthesia [23 vs. 13 (p = 0.024)]. The major finding was a significant difference in elevated beta2-microglobulin (B2MG) [23 vs. 13 (p = 0.024)]. Other studied factors, suggested in the literature as significant in the pSS-related neuropathy, were not statistically different between the groups. Conclusion: Our study confirms that CTS is more prevalent among pSS patients than in the general population and suggests that a new approach is required towards the pathogenesis of this phenomenon. We hypothesize that CTS is more associated with an overall disease activity than joint involvement as such. [ABSTRACT FROM AUTHOR]

Copyright of Studia Paedagogica Ignatiana is the property of Jesuit University Ignatianum in Krakow and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vitamin B12 (cobalamin) deficiency is common in patients with rheumatic diseases. Pernicious anemia is a well-known cause, but recent reports suggest that autoimmune-derived deficiency may not be limited to this cause alone. Symptoms of low vitamin B12 concentration are often deceptive, mimicking and overlapping with symptoms of other conditions. Neuropsychiatric manifestations, anemia, and fatigue are frequently attributed to a rheumatic disease without further evaluation. In this study, we present three cases of patients with neuropathic pain, depression, fatigue, and muscle weakness, initially attributed to a rheumatic disease, which almost completely resolved after implementing vitamin B12 supplementation. Furthermore, we provide an overview of current scientific reports regarding the potential use of cobalamin in rheumatology. Treatment of pain and neuropathy, often very challenging in long-lasting rheumatic diseases, can be more effective after a course of vitamin B12, even when no apparent deficiency is detected in laboratory tests. Considering recent research demonstrating vitamin B12's nerve-protecting properties, we recommend that physicians should assess vitamin B12 levels early in the diagnostic process of rheumatic diseases. In specific cases, physicians should consider cobalamin supplementation regardless of vitamin B12 serum concentration. [ABSTRACT FROM AUTHOR]

We describe the results of eculizumab treatment of a patient with pachymeningitis, inflammatory infiltration of the left frontal lobe, and cerebral hematoma, who presented with progressive vision loss, epileptic seizures, and abnormal pattern of the complement system parameters. A 30-year-old female patient, initially diagnosed with hypereosinophilia and a tumour of the left orbit, developed a significant visual impairment in the left eye, progressive vision loss in the right eye, and neurological symptoms in the form of epileptic seizures and behavioural changes. Magnetic resonance imaging (MRI) revealed thickening of the dura mater in the left frontal area, slight oedema of the cortex, and subcortical white matter. Orbit biopsy showed non-specific inflammatory infiltrates. Despite the initial good response, symptoms progressed during treatment with glucocorticoids and immunosuppressants. Increased activity of the alternative complement pathway accompanied by a low level of its main inhibitor, factor H (FH), and the presence of anti-FH autoantibodies, was found. Genetic analysis revealed several missense variants of complement proteins, including two disease-linked mutations in FH (p.H402Y) and FI (T300A). An attempt to apply a complement C5 blocker, eculizumab, has been made. Neurological symptoms subsided, vision loss was inhibited, laboratory parameters improved, and discontinuation of steroid therapy was possible. The case underlines the role of complement system dysregulation in neurological distress. [ABSTRACT FROM AUTHOR]

Copyright of Horyzonty Wychowania is the property of Jesuit University Ignatianum in Krakow and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The first records of Sticta andina and S. scabrosa subsp. scabrosa from Bolivia are presented. All records are confirmed by molecular data. Sticta andina has flattened, marginal isidia and phyllidia with abundant, submarginal apothecia, while tomentum is dark brown to black, whereas, S. scabrosa subsp. scabrosa has marginal and laminal phyllidia and pale to dark, grey tomentum. Two Bolivian specimens of the latter possess sparse, marginal to laminal apothecia, which previously have not been observed in this species. The haplotype network indicates that the S. andina specimens from Bolivia have three haplotypes, two of which are different from those previously reported. In the case of S. scabrosa subsp. scabrosa, two haplotypes were found, of which one is newly reported. A distribution map of Sticta species confirmed for Bolivia is presented. [ABSTRACT FROM AUTHOR]

The global response to the COVID-19 pandemic has been successfully driven by efforts to ramp up access to vaccines. Pregnant or breastfeeding women and their children have not benefited from the vaccines despite their susceptibility to the virus. We investigated whether women who were offered vaccination after delivery passively transferred protective antibodies to their infants via breast milk. Serum was collected from breast feeding mother–infant pairs and analysed for levels of antibodies to the SARS-CoV-2 spike protein using the CLIA chemiluminescence technique. Data were analysed for the significance of the differences using the Mann–Whitney U test and the Spearman's rank correlation coefficient to determine the strength of the correlation. A total of 13 mothers, mean age 34.86 (95%CI = 33.21–36.48) years and their infants, mean age 15.77 (95%CI = 11.24–20.29) months were enrolled. The mothers had completed their courses of the mRNA BNT162b2 SARS-CoV-2 vaccine during breastfeeding, 8.3 (95%CI = 7.24–9.36) months before the study. All 13 mothers had detectable antibodies to the SARS-CoV-2 spike protein, mean 1252, (95%CI = 736–1769) BAU/mL. Antibodies were detected in 3/13 (23%) breast-fed infants mean 322, (95%CI = 252–897) BAU/mL. There was no correlation between the maternal and infant IgG antibody titres. The time-lag since full vaccination did not correlate to the presence of antibodies in infant sera. Maternal or infant ages did not correlate to the presence of antibodies. Although some children (23%) had anti-SARS-CoV-2 antibodies, there was no association between vaccine-induced COVID-19 spike protein specific maternal IgG antibody titres and the presence of antibodies in the breastfed infants. The data show that the transfer of passive immunity to infants following post-partum vaccination with the mRNA BNT162b2 SARS-CoV-2 vaccine may be infrequent in this population. [ABSTRACT FROM AUTHOR]

Vibrio cholerae is a well-studied human pathogen that is also a common inhabitant of marine habitats. In both environments, the bacterium is subject to interbacterial competition. A molecular nanomachine that is often involved in such competitive behavior is the type VI secretion system (T6SS). Interestingly and in contrast to non-pandemic or environmental isolates, the T6SS of the O1 El Tor clade of V. cholerae, which is responsible for the ongoing 7th cholera pandemic, is largely silent under standard laboratory culture conditions. Instead, these strains induce their full T6SS capacity only under specific conditions such as growth on chitinous surfaces (signaled through TfoX and QstR) or when the cells encounter low intracellular c-di-GMP levels (TfoY-driven). In this study, we identified a single nucleotide polymorphism (SNP) within an intergenic region of the major T6SS gene cluster of V. cholerae that determines the T6SS status of the cell. We show that SNP conversion is sufficient to induce T6SS production in numerous pandemic strains, while the converse approach renders non-pandemic/environmental V. cholerae strains T6SS-silent. We further demonstrate that SNP-dependent T6SS production occurs independently of the known T6SS regulators TfoX, QstR, and TfoY. Finally, we identify a putative promoter region adjacent to the identified SNP that is required for all forms of T6SS regulation in V. cholerae. [ABSTRACT FROM AUTHOR]

Horizontal gene transfer can trigger rapid shifts in bacterial evolution. Driven by a variety of mobile genetic elements—in particular bacteriophages and plasmids—the ability to share genes within and across species underpins the exceptional adaptability of bacteria. Nevertheless, invasive mobile genetic elements can also present grave risks to the host; bacteria have therefore evolved a vast array of defences against these elements1. Here we identify two plasmid defence systems conserved in the Vibrio cholerae El Tor strains responsible for the ongoing seventh cholera pandemic2–4. These systems, termed DdmABC and DdmDE, are encoded on two major pathogenicity islands that are a hallmark of current pandemic strains. We show that the modules cooperate to rapidly eliminate small multicopy plasmids by degradation. Moreover, the DdmABC system is widespread and can defend against bacteriophage infection by triggering cell suicide (abortive infection, or Abi). Notably, we go on to show that, through an Abi-like mechanism, DdmABC increases the burden of large low-copy-number conjugative plasmids, including a broad-host IncC multidrug resistance plasmid, which creates a fitness disadvantage that counterselects against plasmid-carrying cells. Our results answer the long-standing question of why plasmids, although abundant in environmental strains, are rare in pandemic strains; have implications for understanding the dissemination of antibiotic resistance plasmids; and provide insights into how the interplay between two defence systems has shaped the evolution of the most successful lineage of pandemic V. cholerae.Two defence systems are identified in pandemic Vibrio cholerae that act both cooperatively and independently to eliminate invasive plasmids and bacteriophages. [ABSTRACT FROM AUTHOR]

Background. The aim of the study was to compare the mechanical properties of three human skeletal muscles: biceps brachii (BB), rectus femoris (RF), and tibialis anterior (TA) at rest measured by myoton device in males (n = 16, mean age 21.2 ± 0.6 years) and females (n = 16; 21.2 ± 0.9 years) and to investigate the influence of skin and subcutaneous tissue thickness (skinfold thickness, SFT) and gender on myometric parameters of the three skeletal muscles. Methods. We measured the following mechanical and viscoelastic muscle properties using MyotonPRO R©: frequency (F [Hz]), decrement (D [log]), stiffness (S [N/m]), relaxation time (R [ms]) and creepability (C [De]). The values of SFT for all selected muscles were assessed by caliper. A mixed-design analysis of variance with gender as between subject comparison was used for assessing the differences between gender and muscles in SFT and each of the myometric parameters separately (F, D, S, R and C). Pearson correlation coefficient or Spearman’s rank correlation coefficient between SFT and myometric parameters was conducted for males, females and males and females together. The level of statistical significance was set at α ≤ 0.05 with Bonferroni correction for multiple comparisons. Results. The SFT over the RF, TA, and BB muscles in women was statistically significantly larger compared with that of males. In females and males, the SFT over the RF was larger than over the TA and BB, and the SFT over the TA was larger compared with over the BB. The values of F and S recorded for the TA muscle were the highest among the three muscles, while D, C, and R were lowest in TA but highest in the RF muscle in men and women. The values of F and S were smaller in females than in males. Gender comparison of D, C, and R values showed that only D for the RF was significantly lower in females than in males, and C for the RF and TA was significantly larger in females than in males. Some correlation between SFT and myometric parameters were different between males and females. For example, there was a significant, negative correlation between SFT and F for all muscles in females, and a significant, positive correlation between these parameters for BB and TA (not for RF) in males. For pooled data (males and females together), a negative significant correlation between SFT and F was observed for RF and TA (not significant for BB muscle). Discussion. It is concluded that the TA compared with the BB and RF has significantly greater F and S but the smallest D and C and the shortest R. Gender and muscle differences in the SFT may affect the measurements of muscle properties using MyotonPRO R©. The relationship between SFT and myometric parameters is different in males and females in the RF, TA, and BB muscles. Therefore, the myometric data should be analyzed in males and females separately. [ABSTRACT FROM AUTHOR]

This study explored the effect of kinesthetic motor imagery training on reaching-to-grasp movement supplemented by a virtual environment in a patient with congenital bilateral transverse upper-limb deficiency. Based on a theoretical assumption, it is possible to conduct such training in this patient. The aim of this study was to evaluate whether cortical activity related to motor imagery of reaching and motor imagery of grasping of the right upper limb was changed by computer-aided imagery training (CAIT) in a patient who was born without upper limbs compared to a healthy control subject, as characterized by multi-channel electroencephalography (EEG) signals recorded before and 4, 8, and 12 weeks after CAIT. The main task during CAIT was to kinesthetically imagine the execution of reaching-to-grasp movements without any muscle activation, supplemented by computer visualization of movements provided by a special headset. Our experiment showed that CAIT can be conducted in the patient with higher vividness of imagery for reaching than grasping tasks. Our results confirm that CAIT can change brain activation patterns in areas related to motor planning and the execution of reaching and grasping movements, and that the effect was more pronounced in the patient than in the healthy control subject. The results show that CAIT has a different effect on the cortical activity related to the motor imagery of a reaching task than on the cortical activity related to the motor imagery of a grasping task. The change observed in the activation patterns could indicate CAIT-induced neuroplasticity, which could potentially be useful in rehabilitation or brain-computer interface purposes for such patients, especially before and after transplantation. This study was part of a registered experiment (ID: NCT04048083). [ABSTRACT FROM AUTHOR]

Our study aimed to determine whether electrical and mechanical factors contributing to acute or long-term maximal torque reduction and muscle soreness due to submaximal eccentric exercise (ECC) are elbow-joint-angle specific and to what extent the joint angle affects the contribution of antagonist coactivation to this torque reduction. Maximal isometric torque (MIT), muscle soreness assessment, agonist electromechanical activities, and antagonist coactivation during the maximal voluntary contraction (MVC) were measured at elbow joint angles of 60°, 90°, and 150° before ECC, immediately after exercise, and 24, 48, 72, and 120 hr after exercise. ECC causes an immediate decrease in MIT as well as increased antagonist coactivation at three angles. Antagonist coactivation returned to its baseline level at 24 hr regardless of joint angle. The most rapid torque recovery and the highest force level at which pain occurred were found after ECC at a joint angle of 60°. During the recovery period, no mechanomyographical changes were observed when measuring surface mechanomyography changes at three angles, while the electrical activity differed between angles. [ABSTRACT FROM AUTHOR]

Introduction: Herlyn-Werner-Wunderlich (HWW) syndrome is a rare congenital anomaly characterized by uterus didelphys with blind hemivagina and ipsilateral renal agenesis. It is one of the rare anomalies of the genitourinary system and is usually identified in the first few years after menarche. Case report: An 18-year-old patient presented with painful menses for 1 year and was suspected for vaginal haematoma. Symptoms appeared 5 years after menarche. Discussion: Magnetic resonance imaging of the pelvis revealed a congenital anomaly of the genital tract. Two steps of surgical management were performed. First, a hysteroscopic incision of the vaginal septa and evacuation of vaginal haematoma were performed. Subsequently, the vaginal septum was partially excised during laparohysteroscopy. Conclusions: Ipsilateral renal agenesis was confirmed by ultrasound during hospitalization, and the diagnoses of obstructed hemivagina and ipsilateral renal anomaly syndrome were established. The aim of this study was to present the diagnostic and therapeutic approaches in HWW syndrome, and to draw attention to the challenges in its diagnosis, which can coexist with multiple complications. [ABSTRACT FROM AUTHOR]

Sjögren's syndrome (SS) is a chronic autoimmune disease with a wide spectrum of possible organ involvement. Peripheral (PNS) and central nervous system (CNS)-related symptoms may occur in the course of the disease. The aim of this study was to compare the health-related quality of life (HR-QOL) in SS patients with and without peripheral neuropathy. The study involved 50 patients with primary Sjögren's syndrome (pSS). All patients underwent neurological clinical examination followed by nerve conduction studies (NCS) and rheumatological examination. Thirty-six-item Short Form Health Survey (SF-36) was used for evaluating HR-QOL. To assess pSS activity, the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) and EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) were used. For the assessment of clinical disability due to peripheral neuropathy, the Overall Disability Sum Score scale (ODSS) was used. Additional evaluation of pain was performed with the use of the Visual Analogue Scale (VAS) and a semistructured interview. Twenty-three (46%) patients were diagnosed with peripheral neuropathy. The most common PNS manifestation was sensorimotor neuropathy (47%). Neurological symptoms preceded the diagnosis of pSS in eight patients. The following domains of the SF-36 form were significantly lower scored by patients with peripheral nervous system involvement: role-physical [0 (0–100) vs. 75 (0–100)], role-emotional [67 (0–100) vs. 100 (0–100)], vitality [40 (10–70) vs. 50 (20–75)], bodily pain [45 (10–75) vs. 55 (0–100)], and general health [20 (5–50) vs. 30 (0–50)] (p ≤ 0.05). Our study showed that peripheral neuropathy was a common organ-specific complication in SS patients. In pSS patients, coexisting neurological involvement with symptoms such as pain and physical disability may be responsible for diminished HR-QOL. [ABSTRACT FROM AUTHOR]

Copyright of Cracow Review of Economics & Management / Zeszyty Naukowe Uniwersytetu Ekonomicznego w Krakowie is the property of Cracow University of Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Review of Medicine / Przeglad Lekarski is the property of Wydawnictwo Przegld Lekarski / Publisher Medicine Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Alzheimer's disease (AD) presents significant therapeutic challenges, with amyloid β1-42 (Aβ1-42) protein aggregation playing a central role in its pathogenesis. Aim: Our study investigates the potential therapeutic efficacy of the isoindolinone derivative 3-(3-oxoisoindolin-1-yl)pentane-2,4-dione (ISOAC1) against Aβ1-42-induced toxicity. Material and methods: We employed spectroscopic and computational approaches to explore ISOAC1's ability to mitigate Aβ1-42 aggregation and its consequent toxicity. Other experimental analyses included Thioflavin T fluorescence assay, and Western blotting. Results: Our findings reveal ISOAC1's capacity to disrupt Aβ1-42 aggregation and hinder its transition towards β-sheet structures. Computational investigations elucidate ISOAC1's binding mechanisms with Aβ1-42, highlighting its potential as a therapeutic agent. Conclusions: ISOAC1 emerges as a promising neuroprotective compound, offering insights into novel therapeutic strategies for AD treatment. The combined spectroscopic and computational approach herein presented provides a comprehensive understanding of ISOAC1's mechanism of action against Aβ1-42-induced toxicity. [ABSTRACT FROM AUTHOR]

Purpose: Heightened tonic stretch reflex contributes to increased muscle tone and a more-flexed resting elbow joint angle (EJA) in patients with Parkinson's disease (PD). Dopaminergic medication restores central nervous system (CNS) functioning and decreases resting muscle electrical and mechanical activities. This study aimed to evaluate the effects of dopaminergic medication on parkinsonian rigidity, resting EJA, resting electrical activity (electromyography, EMG) and mechanical properties (myotonometry, MYO) of elbow flexor muscles and the associations of EJA with these muscles resting electrical activity and mechanical properties in PD patients. We also evaluated a relationship between dopaminergic treatment dose and these outcome measures values. Methods: Ten PD patients (age 68 ± 10.1 years; body mass 70 ± 16.8 kg; height 162 ± 6.6 cm; illness duration 9 ± 4.5 years) were tested during medication on- and off-phases. Resting EJA, myotonometric muscle stiffness (S-MYO) and root mean square electromyogram amplitude (RMS-EMG) were recorded from relaxed biceps brachii and brachioradialis muscles. Based on the above parameters, we also calculated the EJA/S-MYO ratio and EJA/RMS-EMG ratio. Parkinsonian rigidity was assessed using the motor section of the Unified Parkinson's Disease Rating Scale. Results: EJA, EJA/S-MYO ratio, and EJA/RMS-EMG ratio were increased and S-MYO, RMS-EMG, and parkinsonian rigidity were decreased during the medication on-phase compared with the off-phase. In addition, the dopaminergic treatment dose was negatively correlated with S-MYO and RMS-EMG, and positively correlated with EJA/SMYO and EJA/RMS-EMG ratios. Conclusions: We conclude that dopaminergic medication- induced improvements in resting elbow joint angle in tested patients with PD are related to changes in their muscle electrical and mechanical properties. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine an effect of myotonometric records' number on stiffness measurements' reliability in muscles at rest and contraction. Methods: Muscle stiffness was measured using Myoton-3 device. Twenty records were taken for: (i) biceps (BB) and triceps brachii (TB) at rest and for BB at 10% of maximal voluntary contraction (MVC) in healthy elderlies (HE) and in Parkinson's disease patients (PD); and (ii) brachioradialis (BR) at rest and at 25, 50 and 80% MVC in healthy young (HY) subjects. Also, in HY group, the 3-records mode was used for BR's measurements at maximal contraction. Each measurement taken with 20-records was classed into five records groups: the whole 20- and the first 15-, 10-, 5- and 3-records. Test-retest reliability for these records groups was analyzed. Results: In HE and PD group measurements' reliability was excellent for all groups of records (20-3 records). In HY group, for the five groups of records taken at rest and submaximal levels of contraction (25, 50 and 80% MVC) the measurements reliability: (i) was mostly excellent or rarely average; and (ii) only in one per three 50% MVC conditions was unacceptable, i.e., for the 3-records group. The reliability of 3-records mode measurements at maximal contraction were unacceptable. Conclusions: Reliable myotonometric stiffness measurements in muscles at rest and during submaximal contractions can be achieved with less than 20 records (15, 10, 5 records) and even for the most of measurements with 3 records in HY and HE as well as in the PD patients. Myotonometric stiffness measurements with 3-records mode during maximal contraction were not reliable. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the trends of the first three power spectral moments of the mechanomyogram (MMG) signal recorded by a microphone (MMG(MIC)) and an accelerometer (MMG(ACC)) during sustained contractions. MMG signals were recorded from the biceps brachii muscle in 14 healthy male subjects during a 3 min isometric elbow flexion at 30% of the maximal voluntary contraction. MMG absolute and normalised root mean square (RMS), mean power frequency (MNF), power spectral variance (Mc2), and skewness (mu3) were computed. For both MMG(MIC) and MMG(ACC), absolute and normalised RMS and Mc2 increased while MNF and mu3 decreased with contraction time (P<0.001). The rates of change of RMS over time were significantly correlated (P<0.001) for MMG(MIC) and MMG(ACC) but not correlated for spectral moments. The coefficient of variation of RMS was higher for MMG(MIC) than for MMG(ACC), while the opposite was observed for mu3 (P<0.05). It was concluded that higher order spectral moments of the MMG signal change during sustained contraction, indicating a complex modification of the shape of the power spectrum and not just scaling of the bandwidth. This is most likely due to the additional motor unit recruitment with fatigue and to the non-linear summation of motor unit contributions to the signal. Moreover, the characteristics of MMG signals recorded with microphones and accelerometers have important differences, which should be taken into account when comparing results from different studies. [ABSTRACT FROM AUTHOR]

Introduction: Earlier studies suggest increased serum levels of thyroid peroxidase antibodies (TPOAb) in some cases with non-autoimmune hyperthyroidism. The aim of the study was to assess the incidence of hypothyroidism in patients with nodular toxic goitre and toxic adenoma at 12 months after radioactive iodine therapy in the relation to TPOAb levels. Patients & Measurements: The study comprised 100 patients (83 females; 17 males) treated with radioactive iodine therapy. Serum concentrations of thyrotropin, free thyroxin, TPOAb, and anti-TSH receptor antibodies were assessed at baseline and 12 months after radioactive iodine therapy. Results: High TPOAb level (> 60.0 IU/mL) was found in 27 % of patients at baseline and 32 % at the follow-up. Baseline TPOAb values were higher in subjects with coexisting non-thyroid autoimmune disease (p = 0.041). After radioactive iodine therapy, the mean TPOAb level increased in patients with normal baseline TPOAb (p = 0.03) and the rates of euthyroidism and hypothyroidism were 61 and 34 %, respectively. The rate of hypothyroidism after radioactive iodine therapy was not significantly different in groups with normal and high baseline TPOAb. Conclusions: 27 % of patients with non-autoimmune hyperthyroidism were positive for TPOAb. However, baseline TPOAb level did not influence the rate of hypothyroidism at 12 months after radioactive iodine therapy. Our results suggest a more close surveillance after radioactive iodine therapy of patients harboring these antibodies. [ABSTRACT FROM AUTHOR]

Copyright of Education of Economists & Managers / Edukacja Ekonomistow i Menedzerow is the property of Warsaw School of Economics, Department of Human Capital Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Natural competence, the ability of bacteria to take up exogenous DNA and incorporate it into their chromosomes, is in most bacteria a transient phenomenon under complex genetic and environmental control. In the Gram-negative bacteria H aemophilus influenzae and V ibrio cholerae, the master regulator Sxy/ TfoX controls competence development. Although not known to be naturally competent, E scherichia coli possesses a Sxy homologue and a competence regulon containing the genes required for DNA uptake. Here, we show that in contrast to other characterised Gamma-proteobacteria, E . coli Sxy is positively autoregulated at the level of transcription by a mechanism that requires cAMP receptor protein ( CRP), cyclic AMP ( cAMP) and a CRP-S site in the sxy promoter. Similarly, we found no evidence that Sxy expression in E . coli was regulated at the translational level. However, our analysis revealed that Sxy is an unstable protein and that its cellular level is negatively regulated at the post-translational level via degradation by Lon protease. Interestingly, in the Gram-positive model organism B acillus subtilis, the competence master regulator ComK is also positively autoregulated at the level of transcription and negatively regulated by proteolysis. Together, these findings reveal striking similarities between the competence regulons of a Gram-positive and a Gram-negative bacterium. [ABSTRACT FROM AUTHOR]

Purpose: Surface electromyogram (EMG) spike shape analysis (SSA) has recently been proposed as an adjunct tool to EMG time and frequency domain analysis to increase our knowledge of motor unit (MU) control strategies. The study was aimed to understand more in MU deactivation strategy during torque decrement, and its possible changes in fatigued muscle, using a combination of traditional time and frequency domain analysis and SSA techniques. Methods: EMG was detected from the biceps brachii of 11 untrained male subjects during static down-going ramp contractions (90-0 % of the maximal voluntary contraction, MVC) under non-fatigued (DGR) and fatigued (FDGR) conditions. The root mean square (RMS) and mean frequency (MF), as well as SSA parameters, were calculated on 1-s EMG windows centred on each 10 % MVC step for both conditions. Results: In both the DGR and FDGR EMG-RMS, mean spike amplitude and mean spike slope decreased by 50 % in the 90-60 % MVC. The mean spike frequency also decreased by 50 % in the 30-10 % MVC. Except the 'mean number of spikes per second' all the other estimated EMG parameters were significantly different during FDGR compared to DGR. Conclusion: The dynamics of EMG parameters during torque decrement would support a MU deactivation strategy which relies more on MU de-recruitment in the high % MVC range and more on firing rate reduction in the low % MVC range. The adopted integrated approach to EMG signal processing could indicate that SSA is an important tool to disclose alterations in motor control due to fatigue. [ABSTRACT FROM AUTHOR]

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Copper and silver N-heterocyclic carbene ( NHC) complexes were prepared through a simple, base-free protocol involving the decomposition of corresponding imidazol(in)ium-2-carboxylates under thermolytic conditions and a subsequent reaction of the in situ generated carbenes with copper(I) or silver(I) chloride, respectively. The desired NHC metal complexes were isolated with good yields after simple crystallization. [ABSTRACT FROM AUTHOR]

Background: Based on Davis's law, greater tonus of the muscle belly in individuals with Parkinson's disease can create greater tension in the tendon, leading to structural adjustment and an increase in tendon stiffness. Our study aimed to separately assess passive stiffness in the muscle belly and tendon in medicated patients with Parkinson's disease, using myotonometry. Methods: We tested 12 patients with Parkinson's disease and 12 healthy matched controls. Passive stiffness of muscle belly and tendon was estimated by myotonometry, electromyography, and mechanomyography in relaxed biceps and triceps brachii muscles. Results: Compared with controls, patients with Parkinson's disease had higher stiffness in the muscle belly and tendon of the biceps brachii and in the tendon of the triceps brachii. In patients with Parkinson's disease, there was a positive correlation between muscle belly stiffness and parkinsonian rigidity in the biceps brachii. Conclusion: Patients with Parkinson's disease have higher passive stiffness of the muscle belly and tendon than healthy matched controls. © 2011 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Background. After hemiparetic stroke, coordination of the shoulder flexor and elbow extensor muscles during a reaching movement is impaired and contributes to poor performance. Objective. The aim was to determine whether functional coupling between electromyographic signals of synergist muscles during reaching was weakened in stroke patients who had poor motor coordination. Methods. Surface electromyography (EMG) from the anterior deltoid, triceps brachii, biceps brachii, pectoralis major, supraspinatus, and latissimus dorsi of the affected upper limb in 11 stroke patients (mean Fugl-Meyer upper extremity score 27 ± 8) and in the dominant arm of 8 healthy controls were measured. Results. Coherence between the EMG of the anterior deltoid and triceps brachii, 2 synergists for reaching, was lower in patients compared with controls, in the 0- to 11-Hz range. Detailed segmented frequency-range analysis indicated significant differences in the coherence between groups in 0- to 3.9-Hz and 4- to 7.9-Hz ranges. Conclusions. This weakened functional coupling may contribute to poor reaching performance and could be a consequence of a loss of common drive at the frequency bands as a result of interruption of information flow in the corticospinal pathway. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to assess the electromyographic (EMG) and mechanomyographic (MMG) activities of agonist and antagonist muscles in Parkinson disease patients during maximal isometric elbow contraction in flexion and extension. Ten elderly females with Parkinson disease (average age 75 years) and 10 age-matched healthy females were tested. The torque and the EMG and MMG signals from biceps brachii and triceps brachii were recorded during sustained maximal voluntary isometric contraction of the elbow flexors and extensors. There were no intergroup differences in the EMG and MMG activities of agonist and antagonist muscles or in torque. This might be because the Parkinson subjects were tested during their medication 'ON' phase, or perhaps maximal isometric contraction (MVC) induced greater active muscle stiffness that affected the MMG signal. Muscle Nerve 40: 240-248, 2009 [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate changes in mechanomyographic (MMG) and the surface electromyographic (EMG) signals during and after fatiguing shoulder eccentric contractions in a group consisting of 12 males and 12 females. Exerted force, MMG, EMG, pain and rate of perceived exertion were assessed before, during and after repeated high-intensity eccentric exercises. Bouts of eccentric contractions caused a decrease in the exerted force for males ( P<0.05) and an increase in the rate of perceived exertion and pain for both genders ( P<0.05). During eccentric exercise, the root mean square (RMS) values of the MMG signal increased ( P<0.05). The mean power frequency (MPF) values of the EMG signal decreased at the end of each eccentric bout for both genders ( P<0.05); the decrease was higher for females compared with males ( P<0.05). Immediately after eccentric exercise in static abduction of the upper limbs, the MMG RMS and MPF values increased ( P<0.05). The present study showed that (1) neuromuscular changes associated with pain and changes in muscle stiffness and (2) changes in motor units strategy during fatigue development in shoulder muscle are reflected in the MMG and EMG signals. [ABSTRACT FROM AUTHOR]

The aim of the study was to estimate the influence of force changes during relaxation from maximal voluntary contraction (MVC) of elbow flexors on electrical (EMG) and mechanical (MMG) activity of synergists and anatgonists at different joint angles. Repeated studies were conducted on 22 young female students to estimate the EMG and MMG activity of the biceps brachii (BB), brachioradialis (BR), and triceps brachii (TB) muscles during relaxation from MVC at an optimal angle (the angle at which a subject achieved MVC=Lo), as well as at angles that were smaller (Ls=Lo-30°) and bigger (Ll=Lo+30°). Four testing sessions consisted of 2-s or 3-s MVC at each angle with simultaneous recording of EMG and MMG signals from BB, BR, and TB muscles. The EMG/MMG probes were used to record EMG and MMG signals. The results showed that the slow relaxation rate was related to a percentage decrease of the EMG amplitude (as measured by root mean square; EMG RMS) of the synergists, while the fast relaxation was related to the EMG RMS of the antagonist, independent of the joint angle. The MMG amplitude (MMG RMS) increased gradually during slow and fast relaxation (compared to the MMG RMS at MVC), indicating a bigger muscle oscillation during relaxation; the changes were related to the muscle tested and joint angle. It was found that, during the slow relaxation, the MMG RMS reflects the force amplitude changes in the BB muscle and the velocity of force changes in the BB and TB muscle (but not in the BR). During the fast relaxation, the MMG amplitude reflects a change in muscle force in the TB and BB muscles (but not in the BR), and the velocity of force changes in the synergists (not in the antagonist). The different contribution of the force and velocity of force changes during slow and fast relaxation to the MMG signal in the three muscle tested can be related to the different deactivation time of each muscle. In conclusion, the present results indicate that MMG recordings might be useful to measure the fast relaxation of individual muscle during voluntary contraction, but this needs be tested on isolated muscle. [ABSTRACT FROM AUTHOR]

Examines the influence of elbow joint angle on phases of force development during maximal voluntary contraction. Relation between joint angle and force development speed; Reproducibility of measured indices at optimal, short and long muscle lengths; Characteristics of maximal voluntary contraction for four muscle lengths.

Introduction: Standard electromyography (EMG) parameters have limited utility for evaluation of Parkinson disease (PD) tremor. Spike shape analysis (SSA) EMG parameters are more sensitive than standard EMG parameters for studying motor control mechanisms in healthy subjects. SSA of EMG has not been used to assess parkinsonian tremor. This study assessed the utility of SSA and standard time and frequency analysis for electromyographic evaluation of PD-related resting tremor.Methods: We analyzed 1-s periods of EMG recordings to detect nontremor and tremor signals in relaxed biceps brachii muscle of seven mild to moderate PD patients.Results: SSA revealed higher mean spike amplitude, duration, and slope and lower mean spike frequency in tremor signals than in nontremor signals. Standard EMG parameters (root mean square, median, and mean frequency) did not show differences between the tremor and nontremor signals.Conclusions: SSA of EMG data is a sensitive method for parkinsonian tremor evaluation. [ABSTRACT FROM AUTHOR]