Characteristic of herd immunity among the population of Stavropol region amid the COVID-19 epidemic

Introduction. The first pandemic in the 21st century, caused by the pathogenic representative of the coronavirus SARS-CoV-2, began in the Chinese city of Wuhan, where the first outbreak of coronavirus pneumonia was recorded in December 2019. The disease spread so quickly around the world that already on February 11, 2020, WHO was forced to declare a pandemic of the “coronavirus disease 2019” COVID-19. The first case of COVID-19 in the Stavropol Territory was registered on March 20, 2020, and three weeks later, starting from the 15th week of the year, a steady increase in the incidence began, which lasted until the 52nd week. During the study period, the incidence increased from 21.1 to 28.3 per hundred thousand of the population. Growth 1.3 times.Purpose: to determine the dynamics of population immunity among the population of the Stavropol Territory in 2020-2021. during the period of an epidemic increase in the incidence of COVID-19. Materials and methods. The SARS-CoV-2 study was carried out according to a unified methodology within the framework of the program for assessing the population immunity of the population of the Russian Federation, developed by Rospotrebnadzor with the participation of the St. Pasteur. In total, 2688 people were examined, divided into 7 age groups. In the examined individuals, the level of specific IgG to the SARS-CoV-2 nucleocapsid was determined by the enzyme immunoassay.Results. The level of seroprevalence among residents of the Stavropol Territory was 9.8%. The largest proportion of seropositive individuals was found in the age groups 1-6 and 7-13 years old (19.2% and 19.7%, respectively). Seroprevalence had no gender differences and ranged from 9.3% to 10.8%. When assessing the distribution of the proportion of seropositive persons in different geographic territories of the region, it was found that the maximum proportion was found in the Kochubeevsky district (23.1%), the minimum in Kislovodsk (7.7%). Among convalescents, the content of specific antibodies to SARS-CoV-2 was noted in 73.3%, which is 7.8 times higher than the average population level. When conducting seromonitoring in the 2nd half of 2020, a 10-fold increase in seroprevalence was recorded, accompanied by a decrease in incidence from the 5th week of 2021. Among asymptomatic volunteers in whom SARS-CoV-2 RNA was detected by the polymerase chain reaction, antibody titers to viruses were found in 78.6%, which corresponds to the seroprevalence of convalescents. The proportion of seropositive persons among those who have come into contact with COVID-19 patients was 16.4%, (1.8 times higher than the average for the population). Out of 262 seroprevalent volunteers, the asymptomatic form of SARS-CoV-2 was detected in 92% of the examined, which indicates a significant role of the number of asymptomatic forms of infection in the epidemic process of COVID-19.Conclusion. The results of assessing the population immunity of the population of the Stavropol Territory indicate that it has not yet reached the threshold level at which a decrease in the intensity of the COVID-19 epidemic process can be expected.

Non-erosive gastroesophageal reflux disease determination criteria by functional tests: a predictive model based on multivariate analysis

Background: Gastroesophageal reflux disease (GERD) in 2009 presented a prevalence of 11.5% in Venezuela. It is a complex, multifactorial disease that is difficult to define, since it consists of several signs and symptoms that may or may not coexist together, both in the presence and absence of the disease.Methods: A prospective study was conducted that consisted of a group of 85 patients diagnosed with non-erosive gastroesophageal reflux disease (NERD) and 20 asymptomatic volunteers. Functional tests were conducted on both groups that included high resolution manometry, 24-hour pH-metry - impedance study. The chi-square independence test, principal component analysis and multiple correspondence analysis were applied to identify which variables showed greater association and importance for the diagnosis of NERD.Results: The results indicated that it is possible to establish a rapid diagnostic test based on the solid drink test, distal contraction index, peristaltic jumps and presence of heartburn with a sensitivity of 96% and specificity of 90%.Conclusions: It is possible to establish a NERD rapid diagnostic test based on functional tests.

Synchronous imaging of pelvic geometry and muscle morphometry: a pilot study of pelvic retroversion using upright MRI

This study investigated feasibility of imaging lumbopelvic musculature and geometry in tandem using upright magnetic resonance imaging (MRI) in asymptomatic adults, and explored the effect of pelvic retroversion on lumbopelvic musculature and geometry. Six asymptomatic volunteers were imaged (0.5 T upright MRI) in 4 postures: standing, standing pelvic retroversion, standing 30° flexion, and supine. Measures included muscle morphometry [cross-sectional area (CSA), circularity, radius, and angle] of the gluteus and iliopsoas, and pelvic geometry [pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), L3–S1 lumbar lordosis (LL)] L3-coccyx. With four volunteers repeating postures, and three raters assessing repeatability, there was generally good repeatability [ICC(3,1) 0.80–0.97]. Retroversion had level dependent effects on muscle measures, for example gluteus CSA and circularity increased (up to 22%). Retroversion increased PT, decreased SS, and decreased L3–S1 LL, but did not affect PI. Gluteus CSA and circularity also had level-specific correlations with PT, SS, and L3–S1 LL. Overall, upright MRI of the lumbopelvic musculature is feasible with good reproducibility, and the morphometry of the involved muscles significantly changes with posture. This finding has the potential to be used for clinical consideration in designing and performing future studies with greater number of healthy subjects and patients.

Epicardial adipose tissue volume improves cardiovascular risk reclassification: the Framingham Risk Score example

Introduction Epicardial adipose tissue (EAT) volume can be noninvasively detected by CT and has been suggested to predict major adverse cardiovascular events (MACE). Framingham Risk Score is one of a number of scoring systems used to determine an individual's chances of developing cardiovascular disease, hence identifying who is most likely to benefit from prevention. Objectives The purpose of this study was to determine net reclassification improvement (NRI) and improved risk prediction based on EAT volume, in comparison to a traditionally known cardiovascular risk score, such as the Framingham. Methods 895 asymptomatic volunteers were prospectively enrolled in a single Portuguese center (mean age 51.9±7.7, 78.5% male) and underwent a median follow-up time of 3.7 years (IQR 5.0). EAT volume was measured by Cardiac Computed Tomography (CCT) using a modified simplified method. For NRI assessment, EAT volume as a continuous variable was added to the Framingham Risk Score. Results After 3.7 median years of follow-up, 27 patients developed a MACE. Using NRI, the net proportion of events (netNRIe) that assigned a higher risk was 33.3% (better reclassified), and the net ratio of non-events (netNRIne) was 24.7%, resulting in a net reclassification index (netNRI) of 58.0%. When the new marker was included in the model, 58.0% of patients were better reclassified. In our work, a total of 33.3% of patients who suffered events (n=27) were correctly reclassified and assigned a higher risk. Conclusion EAT volume results in a high reclassification rate in an asymptomatic, low-risk population, demonstrating the benefit of this marker beyond traditional risk assessment models. Our study supports its application, especially in carefully selected individuals. FUNDunding Acknowledgement Type of funding sources: None. Figure 1

Analysis and comparison of pain pressure threshold and active cervical range of motion after superficial and deep dry needling techniques of the upper trapezius muscle

Objectives: To evaluate the changes in pain pressure threshold (PPT) and active cervical range of motion (ACROM) after the application of superficial dry needling (DN) or deep DN in myofascial trigger point (MTrP) 1 of the upper trapezius versus a simulated DN technique in the gastrocnemius muscle (control group). Design: Double-blind, randomized controlled trial with 7-day follow-up. Participants: Asymptomatic volunteers (n = 180; 76 men, 104 women) with a latent MTrP 1 in the upper trapezius were randomly divided into three groups: G1, receiving superficial DN in the upper trapezius; G2, receiving deep DN in the upper trapezius; and G3, control group, receiving simulated DN technique in the gastrocnemius muscle. Main outcome measures: While sitting in a chair, each subject underwent measurements of PPT and ACROM (ipsilateral and contralateral side flexion and rotation, flexion and extension) preintervention, (immediately) postintervention, and at 24 h, 72 h and 7 days. Results: Superficial and deep DN produced an increase in PPT at 7 days with respect to preintervention levels. Furthermore, superficial and deep DN produced a decrease in cervical flexion at 24 h and an increase in ipsilateral rotation until 72 h, increasing to 7 days in the case of deep DN. On the contrary, superficial DN produced an increase in ipsilateral and contralateral side flexion after intervention, unlike deep DN that produced a decrease at 24 h. Furthermore, superficial DN produced an increase in contralateral rotation at 24 h and deep DN decreased extension at 72 h. Conclusion: A single intervention of superficial or deep DN did not produce statistically significant changes in PPT or goniometry measurements. Trial registration number: NCT03719352 ( ClinicalTrials.gov )

The correlation between the labrum size and the labral tear in asymptomatic volunteers and symptomatic patients

Background Some studies have proved that labrum size is associated with symptoms in patients with hip labral tear. The correlation between the labrum size and the labral tear in asymptomatic volunteers and symptomatic patients is still uncertain. Methods The volunteers with no history of pain, injury, or surgery were recruited from the community. Patients who were diagnosed with labral tear and underwent hip arthroscopic surgery in this period in our hospital were also included. The length and height of the acetabular hip labrum were measured at three separate anatomic sites through magnetic resonance imaging (MRI) along the acetabular rim: lateral, anterior, and anteroinferior. Results A total of 70 volunteers (125 hips) and 70 patients (70 hips) were included in this study. Sixty-six (52.8%) hips had labral tears in all 125 hips of volunteers. The lateral labral length of volunteers with labral tears was significantly larger than those without labral tears (P < .05). In 14 volunteers with unilateral labral tears, length of lateral, anterior, and anteroinferior labrum in the side with tear were significantly larger than normal on the other side. The anterior labral height of volunteers was significantly larger than that of patients (P < .05). Conclusions In conclusion, asymptomatic volunteers with larger length of lateral, anterior, and anteroinferior labrum are more prone to present with labral tears. Symptomatic patients with labral tears exhibited thinner anterior labrum. Further studies are warranted to explore the mechanisms of labral tears in asymptomatic people and validate the use of labral size as a guide to differential diagnosis and treatment.

Reliability of a Cycle Sprint Test to Measure Lower Limb Muscle Power

This study examined the reliability of a cycle sprint test for measuring lower limb muscle power. Twenty asymptomatic volunteers completed the test on two occasions, with one week between test sessions. Participants sat on a stationary road bicycle with commercial power meters in the pedal cranks. Maximum and average muscle power was measured during three, 10-second sprint efforts. The test demonstrated excellent within- and between-day reliability for both maximum and average power measurement (ICC=0.93 to 0.97). The within-day Standard Error of Measurement (SEM) was between 25.9W (6.1%) and 35.1W (8.5%), and 24.8 (6.5%) and 28.6W (7.7%) for maximum and average power respectively. The between-day SEM was 34.3W (7.8%) for maximum power and 26.4W (7.1%) for average power. Reliability of the cycle sprint test has been established, along with thresholds for significant change. The cycle sprint test may have relevance in clinical populations to evaluate lower limb muscle power following injury, or to measure rehabilitation outcomes.

Realignment of Ideal Lumbar Lordosis in Correction Surgery: A Novel Predictive Formula

Study design: Retrospective cohort studySummary of Background Data：Restoring the sagittal balance is the significant procedure, which could be evaluated by the relationship of thoracic kyphosis (TK) and lumbar lordosis (LL). Several lumbar lordosis predictive formulas have been proposed. But previous study ignored importance of reciprocal relationship between regional spinal modifications in some ways.Objectives: Realignment of the lumbar lordosis is fundamental in spinal surgery and several formulas have been established to predict the appropriate lumbar lordosis. However, the predictive accuracy of these formulas did not reach their targets. The present study introduced a novel predictive formula for realignment of lumbar lordosis in correction surgery, aiming to predict the individualized ideal lumbar lordosis for different patients.Methods: A total of 311 asymptomatic volunteers were recruited: 220 volunteers for the development of the formula, and the other 91 subjects for validation. General and radiological parameters were evaluated. Correlation analysis between maxLL and other parameters was performed. Multiple regression analysis was conducted to establish the predictive formula using variables related to maxLL. Comparison between predicated maxLL yielded by our formula and other 7 formulas and actual maxLL were conducted to determine the reliability and validity of our predictive formula.Results: MaxLL was correlated with maxTK, SS, PT and PI (all P<0.05). The adjusted multiple regression analysis showed that there were significant associations of maxLL with maxTK and PI (all P<0.001), and the formula was established as follows: maxLL=0.6*maxTK+0.5*PI+3. No significant difference was found between actual maxLL and predicted maxLL yielded by our formula (P=0.408), and our predictive formula has been demonstrated sound reliability and validity. Conclusion: MaxTK and PI were the primary contributors to maxLL, and our novel formula could be safely utilized to predict the ideal lumbar lordosis for patients before surgery.