systematic reviews and meta-analyses

Introduction Spinal pain is one of the leading causes of disability in modern societies. In patients with spinal pain, observation of spinal shape and mobility is a basic component of the physical examination, which is due to a common belief that correcting spinal shape and mobility aberrations can alleviate pain and improve the quality of life. When clinicians aim to normalize dysfunctional spinal shape or mobility, a fundamental basis of physiological reference values in asymptomatic individuals is a prerequisite. Although there is a general understanding that the spinal shape and mobility alter with age and sex, the details of these variations remain lacking. Therefore, an evidence-based description of these differences because of age and sex is essential for an improved treatment. Methods Three systematic reviews were performed to investigate the effect of age and sex on cervical, thoracic and lumbar spinal shape and mobility in asymptomatic adults. Meta-analyzes were additionally performed for the cervical and lumbar spine. The quality assessment tool for quantitative studies was applied to assess the methodological quality. Results The literature search yielded 4037, 897 and 2372 hits for cervical, thoracic and lumbar spinal shape and mobility, respectively. Among these, 34, 45 and 65 studies, respectively, met the inclusion criteria and were included in the systematic reviews. Most were cross-sectional studies with a moderate study design quality. Eleven studies for the cervical and twelve for lumbar spine with similar age descriptions were included in the meta-analyses. Insufficient homogeneous data did not allow a meta-analysis for the thoracic spine. With one-decade age increments from the 20s to 60s, there was an increasing tendency for thoracic kyphosis. Lumbar lordosis changed inconsistently with aging from the 20s to 60s and was greater in females than in males in each age range. Cervical, thoracic and lumbar mobility decreased non-monotonically with aging in each anatomical direction. The effect of sex on spinal mobility was inconsistent in each decade age range and differed among different spinal regions as well among different anatomical directions. Conclusions Quantitative effects of age and sex on spinal shape and mobility in asymptomatic adults were statistically evaluated. These findings allow better discrimination between functional deficits caused by spinal disorders and by physiological adaptive processes during aging. Further longitudinal studies with long-term follow-up including subjects with spinal pain need to be conducted to ensure an extensive comparison between symptomatic and asymptomatic individuals.Einleitung Rückenschmerzen zählen zu den Hauptbeschwerden der heutigen Gesellschaft. Bei Patienten mit Rückenschmerzen ist die Untersuchung der Wirbelsäulenform und ihrer Beweglichkeit ein grundlegender Bestandteil der körperlichen Untersuchung. Es wird allgemein angenommen, dass die Korrektur der Wirbelsäulenform und die Behebung von Bewegungseinschränkungen Schmerzen lindern und die Lebensqualität verbessern kann. Hierfür sind jedoch grundlegende physiologische Referenzwerte von asymptomatischen Probanden nötig. Obwohl bekannt ist, dass die Wirbelsäulenform und ihre Beweglichkeit von Alter und Geschlecht abhängig sind, bleiben die Details dieser Veränderungen immer noch unklar. Eine evidenzbasierte Beschreibung dieser Unterschiede aufgrund von Alter und Geschlecht ist daher für eine Therapie¬verbesserung unerlässlich. Methodik Es wurden drei systematische Reviews erstellt um den Einfluss von Alter und Geschlecht auf die Form und Beweglichkeit der Hals-, Brust- und Lendenwirbelsäule bei asymptomatischen Erwachsenen zu ermitteln. Für die Hals- und Lenden¬wirbelsäule wurden zusätzlich Meta-Analysen durchgeführt. Zur Bewertung der Qualität der Arbeiten wurde das quality assessment tool for quantitative studies verwendet. Ergebnisse Die Literaturrecherche ergab 4037, 897 und 2372 Arbeiten zum Thema Form und Beweglichkeit von Hals-, Brust- bzw. Lendenwirbelsäule. Davon erfüllten 34, 45 bzw. 65 Studien die Einschlusskriterien und wurden für die systematischen Reviews herangezogen. Die meisten Arbeiten waren Querschnittsstudien mit einer moderaten Studiendesignqualität. In elf Arbeiten aus dem Halswirbelsäulen- und zwölf aus dem Lendenwirbelsäulenbereich wurden ähnliche Altersbeschreibungen verwendet und in die Meta-Analysen einbezogen. Aufgrund unzureichender Homogenität der Daten konnte für die Brustwirbelsäule keine Meta-Analyse durchgeführt werden. Mit jeder Lebensdekade zwischen den 20er bis zu den 60er Jahren nahm die Brustwirbelsäulenkyphose zu. Die Lendenwirbelsäulenlordose änderte sich in diesen Altersabschnitten uneinheitlich und war bei Frauen in jeder Altersgruppe im Durch¬schnitt größer als bei Männern. Die zervikale, thorakale und lumbale Beweglichkeit nahm mit zunehmendem Alter richtungsabhängig nicht monoton ab. Die Auswirkungen des Geschlechts auf die Mobilität der Wirbelsäule waren in jedem Jahrzehnt uneinheitlich und unterschieden sich in den verschiedenen Wirbelsäulenregionen sowie in den verschiedenen anatomischen Richtungen. Schlussfolgerung In dieser Arbeit wurden die quantitativen Auswirkungen von Alter und Geschlecht auf die Wirbelsäulenform und ihre Mobilität bei asymptomatischen Erwachsenen statistisch ausgewertet. Die Ergebnisse ermöglichen es, besser zwischen Funktionsstörungen, die durch Wirbelsäulenerkrankungen und solchen, die durch physiologische Anpassungsprozesse während des Alterns verursacht werden, zu unterscheiden. Für einen umfassenden Vergleich, der auch symptomatische Veränderungen umfasst, sind weitere Langzeitstudien mit Langzeit-Follow-up an Patienten mit Rücken¬schmerzen erforderlich

Sex-Dependent Estimation of Spinal Loads During Static Manual Material Handling Activities — Combined in vivo and in silico Analyses

Manual material handling (MMH) is considered as one of the main contributors to low back pain. While males traditionally perform MMH tasks, recently the number of females who undertake these physically-demanding activities is also increasing. To evaluate the risk of mechanical injuries, the majority of previous studies have estimated spinal forces using different modeling approaches that mostly focus on male individuals. Notable sex-dependent differences have, however, been reported in torso muscle strength and anatomy, segmental mass distribution, as well as lifting strategy during MMH. Therefore, this study aimed to use sex-specific models to estimate lumbar spinal and muscle forces during static MHH tasks in 10 healthy males and 10 females. Motion-capture, surface electromyographic from select trunk muscles, and ground reaction force data were simultaneously collected while subjects performed twelve symmetric and asymmetric static lifting (10 kg) tasks. AnyBody Modeling System was used to develop base-models (subject-specific segmental length, muscle architecture, and kinematics data) for both sexes. For females, female-specific models were also developed by taking into account for the female's muscle physiological cross-sectional areas, segmental mass distributions, and body fat percentage. Males showed higher absolute L5-S1 compressive and shear loads as compared to both female base-models (25.3% compressive and 14% shear) and female-specific models (41% compressive and 23.6% shear). When the predicted spine loads were normalized to subjects' body weight, however, female base-models showed larger loads (9% compressive and 16.2% shear on average), and female-specific models showed 2.4% smaller and 9.4% larger loads than males. Females showed larger forces in oblique abdominal muscles during both symmetric and asymmetric lifting tasks, while males had larger back extensor muscle forces during symmetric lifting tasks. A stronger correlation between measured and predicted muscle activities was found in females than males. Results indicate that female-specific characteristics affect the predicted spinal loads and must be considered in musculoskeletal models. Neglecting sex-specific parameters in these models could lead to the overestimation of spinal loads in females

Mechanism of online emotional support accompany group for stress: The role of social support

ObjectiveTo investigate the effect of social support on stress, and to clarify the effect and mechanism of Online Emotional Support Accompany Group (OESAG).MethodsThe group members who signed up for the public welfare project “Psychological Rehabilitation Group Psychological Service under the COVID-19 Pandemic” were divided into the treatment group, the control group, and the blank group with 37 members each. The treatment group received OESAG intervention, the control group received online time management group intervention, and the blank group was the waiting group. The three groups of subjects were synchronously tested before and after the intervention group.ResultsAfter the OESAG intervention, compared with the control group and the blank group, the treatment group showed that perceived social support was improved, and loneliness and stress were decreased.ConclusionImproving social support can effectively reduce stress. OESAG can effectively improve social support and so too decrease stress. This study could help in designing effective psychological intervention measures to reduce the degree of stress symptoms and enhance both personal and social levels of coping with stressful events

Identification of stable reference genes for quantitative gene expression analysis in the duodenum of meat-type ducks

Quantitative polymerase chain reaction (qPCR) is an important method to detect gene expression at the molecular level. The selection of appropriate housekeeping genes is the key to accurately calculating the expression level of target genes and conducting gene function studies. In this study, the expression of eight candidate reference genes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin (β-actin), 18S ribosomal RNA (18S rRNA), hydroxymethylbilane synthase (HMBS), hypoxanthine phosphoribosyltransferase 1 (HPRT1), TATA box binding protein (TBP), ribosomal protein L13 (RPL13), and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein (YWHAZ), in the duodenal epithelial tissue of 42-day-old meat-type ducks were detected using qPCR. Furthermore, their expression stability was analyzed using the geNorm, NormFinder, and BestKeeper programs. The results indicated that HMBS and YWHAZ were the most stably expressed genes. All three programs indicated that the expression of 18S rRNA was the least stable, making it unsuitable for the study of gene expression in meat-type duck tissues. This study provides stable reference genes for gene expression analysis and contributes to further studies on the gene function of meat-type ducks

Simultaneous determination of arsenic selenium and antimony species in biological and environmental materials by atomic spectrometry

Methods for the simultaneous determination and speciation of arsenic, selenium and antimony in complex matrices involving inductively coupled plasma optical emission spectrometry (ICP-OES), and inductively coupled plasma mass spectrometry (ICP-MS) coupled with high performance liquid chromatography (HPLC) were developed and successfully applied to the analyses of various types of environmental and biological samples. A flexible internal standardization procedure for ICP-OES has been developed that extends the choices of possible internal standards and has the potential for greater accuracy than traditional internal standardization based on one standard. This method is based upon the visualization by principal component analysis of the similarity of matrix-induced behavior among emission lines. For a given analytical line, more choices of internal standards are provided from composite spectral lines created by combining real spectral lines in such a way as to integrate their characteristic behaviors. The method was applied with satisfactory results to the determination of As, Sb and Se in solutions which modeled plant and food sample digests to compensate for the matrix effect. A method for the simultaneous determination of As, Sb and Se by the multimode sample introduction system coupled to ICP-OES has been developed. Reaction mechanisms for sample treatment and hydride generation are proposed to account for some unusual observations. In order to study urinary arsenic and selenium metabolism and interactions in the human body, a procedure for the simultaneous determination of six Se species and six As species in human urine by HPLC-ICP-MS has been developed. Positive associations between As intake and urinary Se metabolites, Se intake and urinary As metabolites were found. As and Se interactions may increase the mobility of both species in human tissue or blood, and as a result, more As and Se may be excreted. The competition for methyl groups between As and Se species changes the distribution of As and Se metabolites in human urine. The excretion of methylated species are delayed. The formation of monomethylated species is enhanced while that of multimethylated species is inhibited when both As and Se are ingested

A study of piezoelectric transducers in application to active control of reciprocating compressor noise

The objective of this thesis was to study the feasibility of using piezoelectric transducers in application to active control of compressor noise. A uniformly thin spherical shell was utilized to represent the hermetic shell and an annular space within two concentrically spherical shells was employed to model the gas cavity inside the test compressor. The analytically predicted mode shapes and natural frequencies were found to be in good agreement with experimental measurements. While comparing the analytical prediction and experimental data, it was found that the sound radiation from the top of the test compressor could be best represented by the circular plate model. The shape, size, location, thickness and material properties of piezoelectric actuators and sensors were studied to maximize the modal force and the developed charge. Based on these results, a circular disk-shaped piezoelectric actuator was selected for implementation. Three potential control algorithms were employed, according to the noise spectrum and dynamic characteristics of the test compressor. Due to unstable motor speed associated with motor slippage, the performance of the filtered-x LMS control algorithm showed that only minor noise reduction occurred at some discrete frequencies. A robust feedback controller was designed by loop-shaping the open-loop system transfer function to satisfy a stability criterion. Simulation results showed that a global reduction of about 3 to 5 dB could be expected with this robust feedback controller. Based on the special characteristics of piezoelectric materials, the surface-bonded piezoelectric patch could be employed as an actuator and a sensor simultaneously. Experimental results showed that compressor noise reduction only occurred at discrete frequencies but could not be audibly discerned. Further study of the simply-supported plate showed that this collocated actuator/sensor approach is suitable for applications with low structural density

Morphology of paraspinal muscles in frail and non-frail older adults evaluated through FRAIL scale

Abstract Background Frailty is a condition characterized by the progressive deterioration of physiological functioning, which is closely related to adverse events. Multiple previous investigations applied frailty scales for spine research, and the purpose of this study is to investigate the differences in the morphology of the paraspinal muscles in frail and non-frail older adults evaluated through FRAIL scale. Methods The sample of this retrospectively cross-sectional study consisted of individuals who were ≥ 60 years of age and with lumbar degenerative disease. We divided patients into two groups (0–2 = non-Frail, 3–5 = Frail) according to the FRAIL scale. The cross-sectional area (CSA) and percentage of the fatty infiltration (FI%) of the paraspinal muscles were compared between the two groups. Results The fCSA (functional cross-sectional area) of the non-Frail group (32.78 [28.52, 38.28]) (cm2) was significantly greater than that of the Frail group (28.50 [24.11, 34.77]) (p < 0.001). The ES FI% (erector spinae fatty infiltration rate) (24.83 ± 6.61 vs. 29.60 ± 7.92, p < 0.001) and MF FI% (multifidus fatty infiltration rate) (31.68 ± 5.63 vs. 41.12 ± 7.04, p < 0.001) of the non-Frail group were significantly lower than that of Frail group. Conclusions The paraspinal muscles of elderly Frail patients screened by the FRAIL scale are worse than those of the non-Frail patients, and the ability of the FRAIL scale to distinguish paraspinal muscle morphology has important clinical significance

Construction and Validation of a Nomogram Clinical Prediction Model for Predicting Osteoporosis in an Asymptomatic Elderly Population in Beijing

Background: Based on the high prevalence and occult-onset of osteoporosis, the development of novel early screening tools was imminent. Therefore, this study attempted to construct a nomogram clinical prediction model for predicting osteoporosis. Methods: Asymptomatic elderly residents in the training (n = 438) and validation groups (n = 146) were recruited. BMD examinations were performed and clinical data were collected for the participants. Logistic regression analyses were performed. A logistic nomogram clinical prediction model and an online dynamic nomogram clinical prediction model were constructed. The nomogram model was validated by means of ROC curves, calibration curves, DCA curves, and clinical impact curves. Results: The nomogram clinical prediction model constructed based on gender, education level, and body weight was well generalized and had moderate predictive value (AUC &gt; 0.7), better calibration, and better clinical benefit. An online dynamic nomogram was constructed. Conclusion: The nomogram clinical prediction model was easy to generalize, and could help family physicians and primary community healthcare institutions to better screen for osteoporosis in the general elderly population and achieve early detection and diagnosis of the disease

Construction and Validation of a Nomogram Clinical Prediction Model for Predicting Osteoporosis in an Asymptomatic Elderly Population in Beijing

Background: Based on the high prevalence and occult-onset of osteoporosis, the development of novel early screening tools was imminent. Therefore, this study attempted to construct a nomogram clinical prediction model for predicting osteoporosis. Methods: Asymptomatic elderly residents in the training (n = 438) and validation groups (n = 146) were recruited. BMD examinations were performed and clinical data were collected for the participants. Logistic regression analyses were performed. A logistic nomogram clinical prediction model and an online dynamic nomogram clinical prediction model were constructed. The nomogram model was validated by means of ROC curves, calibration curves, DCA curves, and clinical impact curves. Results: The nomogram clinical prediction model constructed based on gender, education level, and body weight was well generalized and had moderate predictive value (AUC > 0.7), better calibration, and better clinical benefit. An online dynamic nomogram was constructed. Conclusions: The nomogram clinical prediction model was easy to generalize, and could help family physicians and primary community healthcare institutions to better screen for osteoporosis in the general elderly population and achieve early detection and diagnosis of the disease