UMIN-CTR Study Design: trial Number: R000016846.

The main objective of this research work is to develop an effective mathematical model of cardiac conduction system using a heterogeneous whole-heart model. The model is in the form of a system of modified Van der Pol and FitzHugh-Nagumo differential equations capable of describing the heart dynamics. The proposed model extends the range of normal and pathological electrocardiogram (ECG) waveforms that can be generated by the model. The effects of the respiratory sinus arrhythmia (RSA) and the Mayer waves (MW) are both incorporated to modulate the intrinsic frequency of the main oscillator that represents the sinoatrial node. Also, three pathological conditions are incorporated into the model. The heart rate variability (HRV) phenomenon is incorporated into the synthetic ECGs produced which yields valuable information about the cardiovascular health and the performance of the autonomic nervous system. The spectral analysis of the generated RR tachogram delivers power spectrums that resemble those obtained from real recordings. Also, the proposed model generates synthetic ECGs that characteristic the three considered pathological conditions, namely, the tall T wave, the ECG with U wave, and the Wolff-Parkinson-White syndrome. In general, the significance of this research work is in developing a mathematical model that represents the interactions between different pacemakers and allows analysis of cardiac rhythms. To show the effectiveness and the accuracy of the presented model, the results are compared to published results. The proposed model can be a useful tool to study the influences of different physiological conditions on the profile of the ECG. The synthetic ECG signals produced can be used as signal sources for the assessment of diagnostic ECG signal processing devices.

Background: This study aims to assess the levels of visfatin in children and adolescents with autoimmune thyroiditis (AIT) and its relationship with disease-related variables. Methods: The study included 84 children and adolescents with AIT and 84 healthy subjects. Measurements of fasting glucose, insulin, thyroid-stimulating hormone (TSH), free thyroxin (FT4), antithyroid peroxidase antibodies (TPOAb) and antithyroglobulin antibody (TgAb) were completed, with assessment of visfatin levels. Results: Overt hypothyroidism was diagnosed in 58 cases, while subclinical hypothyroidism was diagnosed in 26 of the studied patients. Total studied cases, overt and subclinical subgroups had significantly higher levels of TSH, HOMA-IR, TPOAb, TgAb and visfatin and significantly lower FT4 level compared with the control. Spearman correlation analysis revealed that visfatin was correlated positively with BMI, homeostasis model assessment (HOMA-IR), TSH and TPOAb, while inversely correlation with FT4. In logistic regression analysis, visfatin was correlated only with TPOAb. Conclusions: This preliminary study provides evidence of significantly higher level of visfatin in children and adolescents with AIT. Visfatin might have a potential role in the pathogenesis of AIT, which needs to be validated by measuring immunological responses in children and adolescents with AIT.

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Objectives: To assess serum anti-Müllerian hormone (AMH) levels as an ovarian reserve marker in adolescent girls with autoimmune thyroiditis (AIT) and explore the relationship of this marker with autoimmunity and thyroid function biomarkers. Subjects and methods: This study included 96 adolescent girls with newly diagnosed AIT and 96 healthy, age-and sex-matched controls. All participants were evaluated with detailed history taking and physical examination, thyroid ultrasound, and measurement of levels of thyroid-stimulating hormone (TSH), free thyroxin (FT4), free triiodothyronine (FT3), antithyroid peroxidase antibodies (TPOAb), antithyroglobulin antibody (TGAb), estradiol, total testosterone, and anti-Müllerian hormone (AMH) levels. The LH/FSH ratio was also calculated. Among 96 patients evaluated, 78 were overtly hypothyroid and 18 were euthyroid. AMH levels were significantly lower in participants with overt hypothyroidism and euthyroidism compared with controls. Results: Serum levels of AMH correlated negatively with age, body mass index (BMI) standard deviation score (SDS), and TPOAb, TGAb, and TSH levels but positively with FT4 levels. In multivariate analysis, AMH levels correlated significantly with age (odds ratio [OR]

Background: Chronic low backache is a commonly affecting problem in our population; it has an economic impact due to the consumption of health expenses in its treatment and rehabilitation. Backache interferes with daily activities of life without discriminating age, gender or race, etc. Our study aimed to determine the role of vitamin B-12 in relieving chronic low backache. Methodology: A comparative study was conducted at Baqai University and Fatima Hospital, Karachi, from May 2019 to April 2020. A total of 496 patients were enrolled and divided into two groups; group I was treated with vitamin B-12 (n=256), and group II (n=240) did not receive vitamin B-12 treatment. Pre-treatment Visual Analog Scale (VAS) score and Oswestry Disability Index (ODI) scores were evaluated. Group II was given calcium supplements and Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) for one month, while group I was given intramuscular injections of vitamin B-12 (500 mcg) on an alternate day for a month along with calcium supplements and NSAIDs. Results: Pre-treatment mean VAS and ODI scores were 6.68 ± 1.45 and 30.11 ± 12.7, while post-treatment VAS and ODI scores were subsequently 3.50 ± 2.07 and 17.73 ± 12.7, respectively. At the end of treatment, a remarkable decrease in ODI and VAS scores was observed after treatment with vitamin B-12 (p<0.05). Conclusion: Concurrent use of vitamin B-12 in the treatment of chronic backache had a better impact in relieving backache symptoms than those treated without vitamin B-12.

The most frequent cause of hyperthyroidism in children is Graves’ disease (GD). Vascular endothelium is a specific target of thyroid hormone. The purpose of this study is to assess flow-mediated dilatation (FMD)% and serum von Willebrand factor (vWF) levels in children with newly diagnosed GD to reflect the extent of endothelial dysfunction in those children. In this study, 40 children with newly discovered GD and 40 children who were healthy served as the control group. Both patients and controls had anthropometric assessment, as well as measurements of fasting lipids, glucose, insulin, high-sensitivity C-reactive protein (hs-CRP), TSH, and free thyroxine (FT4 and FT3), thyrotropin receptor antibodies TRAbs and vWF. Noninvasive ultrasound was utilized to quantify the carotid arteries’ intima-media thickness and the brachial artery’s FMD. Patients reported significantly reduced FMD response and greater vWF and hs-CRP levels compared to controls (P = 0.001 for each). In multivariate analysis, we reported that vWF was significantly correlated with TSH (OR 2.5, 95% CI 1.32–5.32, P = 0.001), FT3 (OR 3.4, 95% CI 1.45–3.55, P = 0.001), TRAb (OR 2.1, 95% CI 1.16–2.23, P = 0.01), and FMD% (OR 4.2, 95% CI 1.18–8.23, P = 0.001).  Conclusions: Children with newly diagnosed GD have endothelial dysfunction, which is shown by impaired FMD and increased vWF. These findings support the idea that GD may need to be treated as soon as possible. What is Known:• Graves' disease is the most common cause of hyperthyroidism in children.• vWF is a reliable marker for detection of vascular endothelial dysfunction. What is New:• Children with newly diagnosed Graves' disease may have endothelial dysfunction as reflected by impairment of FMD and raised vWF level.• Measurement of vWF level in children with newly diagnosed Graves' disease can be used for early detection of endothelial dysfunction.

Objectives: Dipping tobacco is highly prevalent worldwide and in Sudan among adult males and is associated with cardiovascular hazards. The main objective of this study was to determine the effects of ‘tombak’ (local name for dipping tobacco in Sudan) dipping on heart rate variability and autonomic functions among adult males. Methods: Blood pressure and heart rate variability were recorded in 60 male tombak users (study group) at least 5 hours before using the tombak and after 30 minutes of use. Forty male non- users of tombak or any other tobacco products were included as a control group. Results: Measurements 5 hours before tombak dipping revealed statistically significant decrease in high frequency power in tombak users. Acute responses to tombak dipping included statistically significant increase in diastolic blood pressure, increase mean arterial pressure, decrease mean NN and decreased square root of the mean squared differences of successive NN intervals. Conclusions: the study results indicated disturbances in the sympatho-vagal balance with domination of sympathetic effects in the regulation of the cardiac activity and peripheral resistance in tombak users.