Isometric torso muscle endurance profiles in adolescents aged 15–18: normative values for age and gender differences

Objective: The aim of this study was to establish normative values for torso muscle endurance in adolescents aged 15–18 years. It was hypothesized that torso endurance profiles of adolescents differs between males and females and between adolescents and adults.

Background: Decreased torso muscle endurance has been identified as a potential personal risk factor for low back pain development in both adolescents and later years together with being detrimental for athletic performance.

Design: Measurement of torso muscle endurance, established through four tests performed in random order in a healthy adolescent population.

Setting: High school in Novi Sad, Province of Vojvodina, Republic of Serbia.

Methods: Two hundred and ninety-four adolescents from one high school (178 males and 116 females) were grouped into four age strata. Selected isometric torso muscle endurance tests were: Biering-Sørensen test for extensor endurance; Flexor endurance test; right and left Side Bridge tests. The mean, ratio, standard deviation and 25th, 50th and 75th percentile scores were determined for each gender/age strata.

Results and conclusion: Males had higher lateral torso endurance than females. Adolescents in general demonstrate their peak lifetime endurance as they appear more endurable than children and comparable adult groups. These data of endurance times, their ratios and percentiles in healthy normal subjects form a database bridging existing data for children and adults that may be useful for guiding training and rehabilitation.     

Modelling foetal growth in a bi-ethnic sample: results from the Born in Bradford (BiB) birth cohort

Background: Attempts to explain the increased risk for metabolic disorders observed in South Asians have focused on the “South Asian” phenotype at birth and subsequent post-natal growth, with little research on pre-natal growth.

Aim: To identify whether divergent growth patterns exist for foetal weight, head (HC) and abdominal circumferences (AC) in a sample of Pakistani and White British foetuses.

Subjects and methods: Models were based on 5553 (weight), 5154 (HC) and 5099 (AC) foetuses from the Born in Bradford birth cohort. Fractional polynomials and mixed effects models were employed to determine growth patterns from ～15 weeks of gestation-birth.

Results: Pakistani foetuses were significantly smaller and lighter as early as 20 weeks. However, there was no ethnic difference in the growth patterns of weight and HC. For AC, Pakistani foetuses displayed a trend for reduced growth in the final trimester.

Conclusion: As the pattern of weight and HC growth was not significantly different during the period under investigation, the mechanism culminating in the reduced Pakistani size at birth may act earlier in gestation. Reduced AC growth in Pakistanis may represent reduced growth of the visceral organs, with consequences for post-natal liver metabolism and renal function.     

Parturition lines in modern human wisdom tooth roots: do they exist,can they be characterized and are they useful for retrospective determination of age at first reproduction and/or inter-birth intervals?

Background: Parturition lines have been described in the teeth of a number of animals, including primates, but never in modern humans. These accentuated lines in dentine are comprised of characteristic dark and light component zones.

Aim: The aim of this study was to review the physiology underlying these lines and to ask if parturition lines exist in the third molar tooth roots of mothers known to have had one or more children during their teenage years.

Methods: Brief retrospective oral medical obstetric histories were taken from four mothers and compared with histological estimates for the timing of accentuated markings visible in longitudinal ground sections of their wisdom teeth.

Results: Evidence of accentuated markings in M3 root dentine matched the age of the mother at the time their first child was born reasonably well. However, the dates calculated for inter-birth intervals did not match well.

Conclusions: Parturition lines corresponding to childbirth during the teenage years can exist in human M3 roots, but may not always do so. Without a written medical history it would not be possible to say with confidence that an accentuated line in M3 root dentine was caused by stress, illness or was a parturition line.     

The role of physical activity,body mass index and maturity status in body-related perceptions and self-esteem of adolescents

Background: Adolescence represents a transitional period which is marked by physical, social and psychological changes. Changes in body shape and physical activity especially alter and shape the psychological well-being of adolescents.

Aim: The purpose of this study was to determine the role of physical activity level, body mass index and maturity status in body-related perception and self-esteem of 11–18 years old adolescents.

Subjects and methods: A total of 1012 adolescents participated in this study. The “Social Physique Anxiety Scale”, “Body Image Satisfaction Scale”, “Physical Self-Perception Profile for Children” and “Rosenberg Self-Esteem Inventory” were administered. Physical activity level and body mass index were assessed using the “Physical Activity Questionnaire” and “Bioelectrical Impedance Analyzer”, respectively.

Results: Regression analysis indicated that body mass index was the only predictor of perceived body attractiveness, social physique anxiety, body image satisfaction and self-esteem for female adolescents. For male adolescents, both physical activity and body mass index were correlated with perceived body attractiveness and social physique anxiety. Pubertal status were not correlated with self-esteem and body-related perceptions for both males and females adolescents.

Conclusion: In summary, body mass index and physical activity plays an important role in body-related perceptions and self-esteem of adolescents.     

Sitting height as a better predictor of body mass than total height and (body mass)/(sitting height)3 as an index of build

Background: The Rohrer Index and the ratio of sitting height (SH) to height fall similarly with growth in early childhood, then level off and rise slightly towards adulthood. In adults the BMI correlates with SH/height. The mean cross-sectional areas of the legs of adults are correlated positively with upper body masses and negatively with leg lengths.

Aim: To find an index of body build that is less dependent on relative leg length and age in children and adults than are the BMI and the Rohrer Index.

Subjects and methods: Published data are analysed to establish the relative importance of SH and leg length as predictors of body mass and to investigate the age dependence of the ratio (body mass)/SH³.

Results: SH is a much better predictor of body mass than height, with leg length being barely relevant. Average values of (body mass)/SH³ vary very little over the age range of 1–25 years, despite small non-random fluctuations.

Conclusion: The ratio (body mass)/SH³ is proposed as a useful “sitting-height index of build” that is superior to the Rohrer Index and could prove better than the BMI as a predictor of adiposity. Further studies are needed, notably using individual data and fat-free masses.     

Weight and height percentiles calculated by the LMS method in Argentinean schoolchildren. A comparative references study

Background: The Argentinean population is characterized by ethnic, cultural and socio-economic diversity.

Aim: To calculate the percentiles of weight-for-age (W/A) and height-for-age (H/A) of schoolchildren from Argentina employing the LMS method; and to compare the obtained percentiles with those of the international and national references.

Subjects and methods: Anthropometric data of 18 698 students (8672 girls and 10 026 boys) of 3–13 years old were collected (2003–2008) from Buenos Aires, Catamarca, Chubut, Jujuy, La Pampa and Mendoza. Percentiles of W/A and H/A were obtained with the LMS method. Statistical and graphical comparisons were established with the WHO (international reference) and with that published by the Argentinean Paediatric Society (national reference).

Results: Differences in W/A and H/A, regarding the references, were negative and greater at the highest percentiles and in most of the age groups. On average, the differences were greater for boys than girls and for national than international references.

Conclusion: The distribution of weight and height of schoolchildren, coming from most regions of the country, differs from those of national and international references. It should be advisable to establish a new national reference based on internationally recognized methodological criteria that adequately reflect the biological and cultural diversity of the Argentinean populations.     

Detecting chronotype differences associated to latitude: a comparison between Horne--Östberg and Munich Chronotype questionnaires

Background: Chronotype, phase preference to perform activities during a 24-hour day, represents distinct circadian temporal organization of living organisms. Morning and evening types can be identified by questionnaires such as Horne and Östberg (HO) and Munich Chronotype Questionnaire (MCTQ). Environmental factors, such as different light–dark cycles experienced at different latitudes, interact with the organisms’ circadian timekeeping system. Therefore, chronotype is expected to vary as a result of different geographical locations.

Aim: To identify differences in chronotype distribution in populations of two Brazilian cities, Natal and Sao Paulo, located at different latitudes.

Subjects and methods: Two specific questionnaires, the Horne and Östberg Questionnaire (HO) and the Munich Chronotype Questionnaire (MCTQ), were used to identify chronotypes of undergraduate students from São Paulo and Natal.

Results: The comparison of the curve distributions of HO and MCTQ scores between both cities allowed one to observe that, while HO curves of São Paulo and Natal overlapped, MCTQ curves showed a clear shift towards eveningness in São Paulo.

Conclusion: This experiment confirmed results from previous studies that the farther away from the equator, the longer the delay of the sleep phase. It was also concluded that MCTQ is better at detecting this phenomenon.     

A metabonomic analysis reveals novel regulatory mechanism of Huangqi injection on leucopenia mice

Context: Huangqi injection (HQI), extracted from Astragali Radix, which has capability on treating the leucopenia. However, the potential metabolic mechanism is poorly understood.

Objective: To investigate the effect of HQI on cyclophosphamide (Cy)-induced leucopenia in mice, the nuclear magnetic resonance (NMR)-based metabolomic profiling technique coupled with multivariate statistical analysis was applied.

Materials and methods: NMR analysis was used to identify the various compounds of HQI, and high-performance liquid chromatography was applied to determine the contents of major compounds. A experimental mice model of leucopenia induced by Cy and NMR-based metabolomic approach was used to evaluate the pharmacological effect of HQI and to investigate its probable acting mechanism on leucopenia.

Results: HQI increased body weight and elevated the white blood cell (WBC), monocytes (MO), neutrophils (NE), and lymphocyte (LY) levels of Cy-treated mice. In addition, the levels of most perturbed endogenous metabolites could be reversed after HQI treatment. Correlations between WBC, MO, NE, LY, and altered metabolite profiles in spleen were greater than that in serum, and the correlation in MO was more evident than those for WBC, NE, and LY.

Discussion and conclusion: HQI showed obvious efficacy on the mice model of leucopenia. And the drug action of HQI on leucopenia was probably related with regulating metabolic pathways of energy metabolism, amino acids metabolism, oxidative stress, and choline metabolism. However, various compounds were present in the HQI, and the bioactive compounds responsible for the drug actions should be further investigated.     

The timing of mandibular tooth formation in two African groups

Background: Ethnic differences in the timing of human tooth development are unclear.

Aim: To describe similarities and differences in the timing of tooth formation in two groups of Sudanese children and young adults.

Subjects and methods: The sample consisted of healthy individuals from Khartoum, Sudan, aged 2–23 years. The Northern group was of Arab origin (848 males, 802 females) and the Western group was of African origin (846 males, 402 females). Each mandibular left permanent tooth from first incisor to third molar was assessed from dental radiographs into one of 15 development stages. Mean ages at entry for 306 tooth stages were calculated using probit regression in males/females in each group and compared using a t-test.

Results: Mean ages were not significantly different in most tooth stage comparisons between ethnic groups for both males (61/75) and females (56/76), despite a tendency of earlier mean ages in the Western group. Mean ages for most tooth stage comparisons between males and females (137/155) were not significantly different within ethnic groups suggesting low sexual dimorphism.

Conclusion: The mean ages of most mandibular tooth formation stages were generally not significantly different between ethnic groups or between males and females in this study.     

Class A dioscorins of various yam species suppress ovalbumin-induced allergic reactions

Context: Dioscorins, the primary storage proteins in yam tubers, of different species exhibited varying immunomodulatory activities in mice. We inferred that this might be attributed to the various isoforms in the yam tubers.

Objective: We aimed to investigate the antiallergic potential of the Class A dioscorins of various yam species using the ovalbumin (OVA)-induced murine allergy model.

Materials and methods: We purified the recombinant Class A dioscorins (rDioscorins) of various yam species from Escherichia coli and evaluated their antiallergic potential by enzyme-linked immunosorbent assay.

Results: The Class A rDioscorins of various yam species suppressed allergic reactions by significantly decreasing the serum IgE and histamine levels. The serum IFN-γ and IgG2a levels significantly increased in all rDioscorin-treated mice. The splenocytes of the rDioscorin-treated mice also exhibited upregulated IFN-γ secretion in response to ConA stimulation. By contrast, the serum IL-5 levels decreased to basal levels in mice treated with Class A rDioscorins and the amount of IL-5 produced by splenocytes decreased in response to ConA stimulation.

Discussion: The Class A rDioscorins suppress allergic reactions, possibly through modulating an imbalanced Th1/Th2 immune response to OVA by promoting Th1 cell responses. Furthermore, the Class A rDioscorins of various yam species exhibited similar immunomodulatory activities in OVA-sensitized mice, which were different from the activities demonstrated by native dioscorins, suggesting that distinct immunomodulatory effects of native dioscorins on mice were attributed to the various isoforms in the yam tubers.

Conclusion: The Class A dioscorins of various yam species exhibit antiallergic activity and are potential immunotherapeutic agents for treating IgE-mediated hypersensitivity.     

Correlation of Proteinuria with Podocyte Foot Process Effacement in IgA Nephropathy: An Ultrastructural Study

Background: Proteinuria is an uncommon clinical manifestation of IgA nephropathy and is usually seen in cases with severe lesions like endocapillary proliferation. However, it is occasionally seen even with cases with mild glomerular manifestations and may even be of nephrotic range.

Predictor: Podocyte foot process effacement.

Outcome: Severity of proteinuria.

Measurements: Podocyte foot process effacement was measured. Morphometric analysis was performed on transmission electron microscope images using a computerized digital photomicrograph system (BioWizard 4.2 Image analysis software, New Delhi, India). Proteinuria was measured quantitatively assigned into five grades.

Results: It was found that as the extent of proteinuria increased, the effacement ratio also increased, and this was most significant between “no” proteinuria and the rest of the categories.

Conclusion: Nephrotic presentation in IgA nephropathy is a known phenomenon and in certain cases may show near normal glomerular morphology with severe foot process effacement on EM being the only significant finding to explain the proteinuria. Proteinuria in these cases shows a significant correlation with degree of foot process effacement. Renal biopsy is important in these cases because they are known to have a better prognosis and are usually steroid responsive.     

Body parameters of Czech breastfed children compared to the Czech references and WHO growth standards

Background: The study concerns the comparison of percentile curves of Czech breastfed children with Czech national references from 1991 and 2001 and WHO growth standards. Growth charts of breastfed children demonstrate different curve shapes, especially in the first months of life. Incorrect interpretation of the growth curve could lead to premature introduction of complementary foods or infant formula.

Aim: The comparison of four body parameters of Czech breastfed children with currently used Czech national references and WHO standards in order to recommend that Czech paediatricians use either Czech references or WHO standards in their practice.

Subjects and methods: Nine hundred and sixty breastfed children were included in the study of length-for-age, head circumference-for-age, weight-for-age and weight-for-length parameters. All percentile curves were compared. Values of the 50th percentile expressed in z-scores based on both Czech references and WHO standards were tested.

Results: The study confirmed results of previous surveys documenting that growth of breastfed children is specific. Nevertheless, percentile curves of growth parameters of Czech breastfed children are closer to Czech references than WHO standards.

Conclusions: The Czech national references fulfil the needs of Czech paediatricians (with pointing to specifics of breastfed child growth) and WHO standards are suitable, especially for international comparison.     

Age as a moderator of the secular trend for grip strength in Canada and the United States

Purpose: To determine whether grip strength changed on average over recent decades at each of two age levels (children and adolescents versus adults) in Canada and the US.

Methods: For each sex, weighted least squares regression analyses were performed on mean grip strength values as reported in studies conducted from the 1960s onwards.

Results: Grip strength did not change significantly as a function of year tested in children and adolescents, whereas it declined as a negatively accelerated function of year tested in adults.

Conclusion: The results are contrary to what might be expected given that body weight has increased in both countries in recent decades and given that grip strength has been found to be positively correlated with body weight. It is suggested that there was a concurrent change in a factor that operated to counteract the effect of increased body weight on grip strength, a prime candidate being a decrease in levels of serum vitamin D. It is also suggested that the secular decline in adult grip strength can be explained by a factor that affects muscular function but which has a long latency period, a prime candidate here being obesity history.     

Is conceptual implicit memory impaired in schizophrenia? Evidence from lexical decision and category verification

Introduction. Implicit memory tasks differ along two orthogonal dimensions, tapping the relative involvement of perceptual/conceptual and identification/production processes. Previous studies have documented a dissociation between perceptual (spared) and conceptual (impaired) implicit memory, using in the latter case a production task (category exemplar generation), in which there is high response competition during the retrieval phase. The present study sought to determine whether the perceptual/conceptual dissociation held when comparing two identification tasks, in which there is no response competition at retrieval.

Methods. In two experiments, repetition priming was assessed in 44 schizophrenic patients and 46 healthy controls in lexical decision (a test based on perceptual identification processes) and category verification (a test based on conceptual identification processes).

Results. Schizophrenic patients achieved a priming as high as that of controls in the lexical decision task. In contrast, only controls exhibited significant priming in the category verification task.

Conclusions. It is concluded that schizophrenia is associated with a specific deficit in conceptual implicit memory, irrespective of the degree of response competition in the test phase.     

PTPN22 Single-Nucleotide Polymorphisms in Iranian Patients with Type 1 Diabetes Mellitus

Background: PTPN22 plays a crucial role in regulating the function of various cells of the immune system, particularly T cells. Polymorphisms of the PTPN22 gene have been associated with many autoimmune diseases, including type 1 diabetes (T1D) which is a T-cell-mediated disease.

Objective: The present study was aimed at genotyping of an Iranian population for five polymorphisms of the PTPN22 gene.

Methods: The study population consisted of 99 T1D patients and 100 healthy controls. We genotyped five single-nucleotide polymorphisms (SNPs) (rs12760457, rs1310182, rs1217414, rs33996649, and rs2476601) of the PTPN22 gene.

Results: Regarding the variant rs2476601, genotypes AG and GG were increased and decreased in T1D patients compared with controls, respectively. Further, alleles G and A of this SNP were found to be decreased and increased in T1D patients, respectively (p value = 0.001). However, T1D and control groups did not differ on genotype distribution or allele frequency for other investigated SNPs.

Conclusions: The PTPN22 rs2476601 minor allele (A) was associated with T1D in Iran, accounting for its pathophysiology in autoimmune diseases.     

Secular trends in cranial morphological traits: a socioeconomic perspective of change and sexual dimorphism in North Americans 1849–1960

Background: The human body has undergone significant changes in stature and other areas, which reflect secular trends associated with socioeconomics.

Aim: To analyse cranial morphological traits for deciphering if they are subject to secular trends.

Subjects and methods: Two documented skeletal collections were sampled for a total of 525 individuals from 1849–1960. Cranial morphological traits were scored and input into time series statistics (logistic regression).

Results: In females, nuchal crests have enlarged, while glabella has decreased. In males, supraorbital margins have dulled, while glabella decreased. Sexual dimorphism increased in supraorbital margins.

Conclusion: The patterns in the data here reflect those found in other areas of the skeleton, namely height, as regards to secular trends. These findings can be extended to stature and cranial changes that parallel socioeconomic trends during the Industrial Revolution, antebellum period and after.     

Effects of cognitive remediation therapy on neurocognition and negative symptoms in schizophrenia: an Italian naturalistic study

Introduction: Cognitive remediation therapy (CRT) has been reported to positively affect neurocognitive processes among patients with schizophrenia; however, the degree to which changes in cognition is linked to improved clinical symptoms, remains poorly understood. The current study aimed to investigate whether cognitive gains were associated to improvements in negative symptoms’ severity in patients with schizophrenia living in two Italian psychiatric facilities.

Methods: Patients with a diagnosis of schizophrenia were consecutively assigned to CRT (n?=?33) and compared with an historical control group (n?=?28). Assessments were performed at baseline and post-treatment using a neuropsychological battery (Trail Making Test A and B, Self-Ordered Pointing Task, California Verbal Learning Test), along with clinical and functioning measures.

Results: Visual attention (TMT-A score change) was found as the only significant predictor of improvement in negative symptoms subscale of the Positive and Negative Syndrome Scale. Furthermore, a mediation path analysis confirmed that better performance in visual attention acts as mediator of the positive association between CRT intervention and lower post-treatment negative symptoms score.

Conclusions: CRT can have a positive impact on a measure of visual attention in patients with schizophrenia and on negative symptoms reduction that is mediated by this significant intervention effect.