Subjective assessment and biochemical evaluation of traction therapy in women with chronic low back pain: does body mass index matter? A clinical study.

BACKGROUND: Apart from the positive effect of lumbar traction on structural changes within the spine in patients with low back pain, it is likely that therapeutic effects are correlated with pain biomarkers in the blood. Among them, systemic metabolic factors related to obesity may play an important role. This is the first study designed to examine the effectiveness of traction therapy in two experimental groups with considerably different BMI and to assess relationships between blood biomarkers and low back pain intensity. METHODS: In the prospective clinical trial, women suffering from chronic low back pain were allocated into the normal-weight or obesity groups. Patients in both groups underwent twenty sessions of lumbar traction therapy (30 min a day, continuous mode with a force level of 25-30% of body weight). Before and after therapy subjective assessments of pain (VAS and PPT) were performed, and serum concentrations of aggrecan chondroitin sulfate 846 epitope (CS-846), neuropeptide Y, leptin, adipsin and growth and differentiation factor 15 (GDF-15) were determined. The data were statistically evaluated for 28 women. RESULTS: After therapy, the maximal low back pain decreased in both groups, GDF-15 concentration was reduced in the normal-weight group and increased in the obesity group, and CS-846 concentration decreased in the obesity group. The sensation of PPT in the lumbar spine and mean concentrations of neuropeptide Y, leptin and adipsin did not change in both groups. However, the relationships of GDF-15, leptin, and adipsin concentrations with the perception of pain were revealed. CONCLUSION: Distinct differences between the normal-weight and obesity groups pointed on the role of excessive adipose tissue in aggravating the inflammatory processes and in the development of low back pain. Adipsin, CS-846 and GDF-15 aspire to be the low back pain biomarkers in women with obesity, but there is a need for further research to answer whether they might be considered reliable biomarkers for the prognosis and monitoring of chronic low back treatment. TRIAL REGISTRATION: NCT04507074, registered prospectively on July 6, 2020.

The Influence of Sacroiliac Joint Manipulation on Changes in the Values of the Center of Pressure in the Process of Maintaining Static Body Balance.

OBJECTIVE: The aim of the study was to determine the influence of manipulative treatment of sacroiliac joint (SIJ) hypomobility on the ability to maintain static balance of the body. METHODS: We compared displacements of the center of pressure (COP) in 2 groups of students of the University of Physical Education: the experimental group (30 people exhibiting SIJ hypomobility) and the control group (29 people without SIJ hypomobility). A manipulation was performed in the experimental group and a placebo procedure in the control group. Sacroiliac joint hypomobility was diagnosed by the following SIJ mobility tests: forward flexion test, Gillet test, long sitting test, lower limb adduction test. These and podometric tests were performed on all participants twice-before and after the procedure. The influence of experimental manipulation was examined by applying repeated-measures analysis of variance, and comparisons were made with Student's t test for dependent and independent samples and nonparametric tests. RESULTS: A statistically significant difference between before and after treatment was found in the experimental group (P < .05) in terms of COP pathway, COP pathway area, and average COP speed. Furthermore, the groups differed in before-treatment values of these parameters in favor of the control group, but after-treatment measurement revealed normalization of the levels of these characteristics in the experimental group to the level of the control group. CONCLUSION: As a result of SIJ manipulation, parameters related to the ability to maintain balance improved in the experimental group.

Effects of Intrauterine Environment on the Magnitude of Differences Within the Pairs of Monozygotic and Dizygotic Twins.

The aim of this study was to determine the effects of intrauterine environment on the magnitude of intrapair differences in six somatic traits of monozygotic (MZ) and dizygotic (DZ) twins (1,263 pairs; 424 MZ twins and 839 DZ twins). Differences in intrauterine environments of MZ twins enforced division of the research material into four groups: (1) MZ-MC-TTTS - MZ twins from monochorionic (MC) pregnancies with twin-to-twin transfusion syndrome (TTTS), (2) MZ-MC (without TTTS)-MZ twins from MC pregnancies without TTTS, (3) MZ-DC-MZ twins from dichorionic (DC) pregnancies, and (4) DZ-DZ twins. The intrapair differences in all analyzed somatic traits, especially body weight and circumference of the chest, were the largest in the case of MZ twins from MC pregnancies with TTTS. DZ twins were the group presenting with the second largest intrapair differences in the analyzed traits. At the end of pregnancy, that is, in lunar months 9 and 10, the magnitude of intrapair differences in all traits of twins from this group was significantly greater than in MZ twins from both MC and DC pregnancies. Irrespective of the analyzed period, the least evident, statistically insignificant intrapair differences in the studied traits were documented in the case of MZ twins from MC pregnancies without TTTS and twins from DC pregnancies. These findings imply that the differentiating effect of intrauterine environment is associated with the occurrence of TTTS, rather than with chorionicity, as postulated previously.

Effect of morphological and functional changes in the secundines on biometric parameters of newborns from dichorionic twin pregnancies.

OBJECTIVES: The aim of the study was to determine if, and to what extent, structural and functional changes of the secundines influence biometric parameters of neonates from dichorionic twin pregnancies. MATERIAL AND METHODS: The study included neonates from dichorionic, diamniotic twin pregnancies, along with their secundines. Based on histopathological examination of the secundines, the mass and dimensions of the placenta, length and condition of the umbilical cord, chorionicity, focal lesions, and microscopic placental abnormalities were determined for 445 pairs of twins. Morphological development of examined twins was characterized on the basis of their six somatic traits, while birth status of the newborns was assessed based on their Apgar scores. Statistical analysis included Student t-tests, Snedecor's F-tests, post-hoc tests, non-parametric chi-squared Pearson's tests, and determination of Spearman coefficients of rank correlation. RESULTS: The lowest values of analyzed somatic traits were observed in twins who had placentas with velamentous or marginal cord insertion. Inflammatory lesions in the placenta and placental abruption turned out to have the greatest impact of all analyzed abnormalities of the secundines. Inflammatory lesions in the placenta were associated with lower values of biometric parameters and a greater likelihood of preterm birth. Neonates with a history of placental abruption were characterized by significantly lower birth weight and smaller chest circumference. CONCLUSIONS: Morphological changes in the secundines have a limited impact on biometric parameters of neonates from dichorionic twin pregnancies. In turn, functional changes exert a significant effect and more often contribute to impaired fetal development.

Impact of McKenzie Method Therapy Enriched by Muscular Energy Techniques on Subjective and Objective Parameters Related to Spine Function in Patients with Chronic Low Back Pain.

BACKGROUND: The high incidence and inconsistencies in diagnostic and therapeutic process of low back pain (LBP) stimulate the continuing search for more efficient treatment modalities. Integration of the information obtained with various therapeutic methods and a holistic approach to the patient seem to be associated with positive outcomes. The aim of this study was to analyze the efficacy of combined treatment with McKenzie method and Muscle Energy Technique (MET), and to compare it with the outcomes of treatment with McKenzie method or standard physiotherapy in specific chronic lumbar pain. MATERIAL AND METHODS: The study included 60 men and women with LBP (mean age 44 years). The patients were randomly assigned to 1 of 3 therapeutic groups, which were further treated with: 1) McKenzie method and MET, 2) McKenzie method alone, or 3) standard physiotherapy for 10 days. The extent of spinal movements (electrogoniometry), level of experienced pain (Visual Analogue Scale and Revised Oswestry Pain Questionnaire), and structure of the spinal discs (MRI) were examined prior to the intervention, immediately thereafter, and 3 months after the intervention. RESULTS: McKenzie method enriched with MET had the best therapeutic outcomes. The mobility of cervical, thoracic, and lumbar spine normalized at levels corresponding to 87.1%, 66.7%, and 95% of respective average normative values. Implementation of McKenzie method, both alone and combined with MET, was associated with a significant decrease in Oswestry Disability Index, significant alleviation of pain (VAS), and significantly reduced size of spinal disc herniation. CONCLUSIONS: The combined method can be effectively used in the treatment of chronic LBP.

Assessment of the stiffness of the upper trapezius muscle in a group of asymptomatic people with cervical spine rotation asymmetry.

This study investigated the relationship between the stiffness of the upper trapezius muscle and the range of rotational movement of the cervical spine. A total of 60 right-handed asymptomatic students participated in the study. Participants (N = 22) characterised by asymmetry in rotational movements were selected for the experimental group. A difference of ≥10° between right and left rotation of the cervical spine was considered asymmetrical. The control group (N = 38) included participants whose rotation difference was < 10°. Belonging to the experimental or control group did not significantly differentiate trapezius muscle stiffness. The rotation side differentiated the stiffness of the right and left trapezius muscles only in the group of people with rotational movement asymmetry. There were high correlation coefficients between right cervical rotation and the stiffness of the muscle on the right side, and between rotation to the left and the stiffness of the muscle on the left side. There is a relationship between the stiffness of the right and left upper trapezius muscles and the range of right and left rotational motion of the cervical spine. Stiffness of the upper trapezius correlates more strongly with rotation to the side on which the muscle lies than to the opposite side. Increased stiffness of the upper trapezius muscle on the side of limited cervical spine rotation is likely to be determined by the muscle fibre stretching mechanism.

Assessment of the Impact of Increased Physical Activity on Body Mass and Adipose Tissue Reduction in Overweight and Obese Children.

(1) Background: Within the last 30 years, growing rates of child overweight and obesity have been observed as a very concerning phenomenon in most countries worldwide. The research aim was to assess what effect increased physical activity has on reducing body mass and adipose tissue in children between 10 and 11 years of age as well as to answer the question of whether physical activity could be considered as a factor in preventing child overweight and obesity when maintaining their existing diet and lifestyle. (2) Material and methods: There were 419 sports class primary school pupils in the experimental group who, in addition to four obligatory weekly physical education hours, attended six training hours. The control group comprised 485 children from parallel non-sports classes. In all pupils, height and weight measurements as well as physical fitness measurements were taken twice, at the beginning and end of the school year. Cole's method was used to assess the children's normal body weight. With the help of this method, children with excessive body weight were selected from the entire study group (N = 904), who additionally had skinfolds and adipose tissue measured using the BIA electrical bioimpedance method. The obtained results were interpreted using the variance analysis for repeated measurements and LSD test. (3) Results: The number of children with excessive body mass after 10 months of increased physical activity decreased (in the case of overweight: p = 0.0014, obesity: p = 0.0022), as did their skinfolds (p ≤ 0.001) and body fat (p ≤ 0.001), while their physical fitness considerably improved compared to the control group. (4) Conclusions: The introduction of increased physical activity in the experimental group children when maintaining their existing diet and lifestyle contributed to reducing their obesity and overweight and, at the same time, proved to be an effective factor in the process of decreasing their excessive body mass.

In search of biomarkers for low back pain: can traction therapy effectiveness be prognosed by surface electromyography or blood parameters?

Background: Lumbar traction therapy is a common method to reduce low back pain (LBP) but is not always effective. The search for biomarkers that would prognose the effectiveness of LBP management is one priority for improving patients' quality of life. Objectives: 1) To determine the phenotype of patients benefiting most from lumbar traction therapy. 2) To correlate systemic and electromyographic biomarkers with pain and pain-related disability. Methods: Data on muscle bioelectrical activity (surface electromyography [SEMG]) in the flexion-extension task, the concentrations of twelve systemic biochemical factors, LBP intensity (Visual Analog Scale), the Oswestry Disability Index, and the Roland-Morris Disability Questionnaire (RMDQ) were collected before and 72 h after 20 sessions of lumbar traction therapy. Patients were divided into responders and nonresponders based on the criterion of a 50% reduction in maximal pain. Results: The responders had lower maximal muscle bioactivity in the extension phase on the left side (p < 0.01) and higher flexion-extension ratios on both sides of the body in the SEMG (left: p < 0.05; right: p < 0.01), and higher adipsin, interleukin-2, interleukin-4, and interleukin-10 concentrations (p < 0.05) than nonresponders. Patients with higher interleukin-4 concentrations before therapy achieved greater reductions in maximal pain in the sitting position, bioelectrical muscle activity in flexion, and flexion-relaxation ratio on the left side of the body. Changes in adipsin and interleukin-4 concentrations correlated with changes in LBP intensity (r = 0.68; r = -0.77). Changes in stem cell growth factor and interleukin-17A correlated with changes in RMDQ (R = 0.53) and bioelectrical muscle activity in extension (left: R = -0.67; right: R = -0.76), respectively. Conclusion: Responders to traction therapy had SEMG indices of less favorable muscle activity in the flexion-extension task and elevated indices of inflammation before the study. For the first time, interleukin-4 was indicated as a potential biomarker for prognosing post-therapy changes in pain intensity and muscle activity.

Sexual dimorphism of lumbar lordosis and lumbar spine mobility during the period of progressive development.

Objective: The objective of this paper is to present possible differences in spondylometric dimorphic characteristics of lumbar spine in the period of progressive development. Material and methods: The research material included 24,517 individuals of both sexes aged from 3 to 25. Individuals that showed abnormal structure of the motor system and individuals reporting pain in the joints of the spine were excluded. Spondylometric research was carried out using the Penny & Giles electrogoniometric measuring system. Significance tests concerning position measurements (Student's t-test, Welch's t-test) were used as well as biometric profiles formed on the basis of Mollison index for each characteristic in the studied period of ontogenesis. The progress of development of the examined spondylometric characteristics in both sex groups was calculated on the basis of expressing the size of the feature in successive age groups as a percentage of its final size. Using the linear and polynomial regression models, the developmental lines of the studied spondylometric parameters were obtained in males and females. Results: In the development process of the studied spondylometric parameters, dimorphic diversity can be observed essentially only in adolescence. In general, in the whole studied period of ontogenetic development, the greater range of lumbar spine mobility is found in females. Minor sexual dimorphism is also evident in the dynamics of development and in the stage of development of the majority of examined characteristics in individual age ranges in relation to the final values, for the benefit of the female sex.

Evaluation of the Combination of Muscle Energy Technique and Trigger Point Therapy in Asymptomatic Individuals with a Latent Trigger Point.

(1) Background: The aim of the study was to determine the effect of the combination therapy of Muscle Energy Technique (MET) and Trigger Point Therapy (TPT) on the angular values of the range of movements of the cervical spine and on the pressure pain threshold (PPT) of the trapezius muscle in asymptomatic individuals. METHODS: The study involved 60 right-handed, asymptomatic students with a latent trigger point in the upper trapezius muscle. All qualified volunteers practiced amateur symmetrical sports. The study used a tensometric electrogoniometer (cervical spine movement values) and an algometer (pressure pain threshold (PPT) of upper trapezius). Randomly (sampling frame), volunteers were assigned to three different research groups (MET + TPT, MET and TPT). All participants received only one therapeutic intervention. Measurements were taken in three time-intervals (pre, post and follow-up the next day after therapy). (2) Results: One-time combined therapy (MET + TPT) significantly increases the range of motion occurring in all planes of the cervical spine. One-time treatments of single MET and single TPT therapy selectively affect the mobility of the cervical spine. The value of the PPT significantly increased immediately after all therapies, but only on the right trapezius muscle, while on the left side only after the therapy combining MET with TPT. (3) Conclusion: The MET + TPT method proved to be the most effective, as it caused changes in all examined goniometric and subjective parameters.

Effectiveness of Combined General Rehabilitation Gymnastics and Muscle Energy Techniques in Older Women with Chronic Low Back Pain.

OBJECTIVE: The aim of this study was to determine the effect of general rehabilitation gymnastics on subjective and objective characteristics of locomotor system in older women with chronic LBP. To satisfy this goal, the outcomes in exercising women were compared with the results of nonexercising controls. MATERIAL AND METHODS: The study group included 21 women with chronic LBP (age 65-75 years), participating in a 3-year general rehabilitation program combining strength, stretching, endurance, balance, and stabilization exercises with Muscle Energy Techniques (MET). Control group included 20 women with chronic LBP, who neither undertook the gymnastics nor participated in other forms of physical activity. The list of outcome measures included pain severity (Numeric Rating Scale), limitations in the activities of daily living (Oswestry Disability Index and Roland-Morris Disability Questionnaire), mobility of all spinal segments (tensometric electrogoniometry), and bioelectrical activity of back muscles (kinesiologic electromyography). RESULTS: Exercising women presented with lesser severity of current pain (by 62%, p<0.001) and pain experienced during the last three months (by 32.5%, p<0.001), reported less ailments during the last three months, and had fewer limitations in the activities of daily living (a 30% decrease in Oswestry Disability Index, p<0.05, and a 65% decrease in Roland-Morris Disability Questionnaire scores, p<0.001) than the controls. Moreover, they showed significantly higher values of nearly all spondylometric parameters except for cervical lateral flexion. The study groups did not differ in the amplitudes of bioelectrical signal from the back muscles. CONCLUSIONS: These findings may point to beneficial effects of the combined exercise program.

DNA variants in Helicobacter pylori infected patients with chronic gastritis, dysplasia and gastric cancer.

PURPOSE: The main scope of this study was to evaluate the importance of selected DNA variants for developing inflammation of gastric mucosa and carcinogenesis in gastrointestinal diseases in patients infected with Helicobacter pylori. PATIENTS AND METHODS: Patients subjected to analysis constituted a group of 131 consecutive cases, with control groups consisting of 100 healthy volunteers and 13 dyspeptic patients. Molecular analysis included the following genes: TP53 (c.743 G > A, c.746 G > A, c.749C > T), MSH2 (c.942 + 3A > T), MLH1 (c.2041 G > A), NOD2/CARD15 (c.3016_3017insC, c.802C > T), IL1A (c.-949C > T) and IL1B (c.315C > T). DNA variants were detected using PCR-RFLP, pyrosequencing and sequencing. RESULTS: Mutations of the analyzed genes were observed more frequently in patients with a higher degree of mucosal lesions (50.9%) than in patients with milder mucosal changes (27.6%). Single mutations and polymorphisms did not affect the course of the disease. Our analysis confirms the influence of the NOD2/CARD15 c.802C > T polymorphism on the development of mucosal changes. A correlation of the frequency of the CT genotype of the NOD2/CARD15 c.802C > T polymorphism with the NOD2/CARD15 c.3016_3017insC mutation was observed. The TT genotype frequency in the c.315C > T IL1B gene polymorphism was statistically significantly higher in patients with mucosa changes. CONCLUSIONS: Accumulation of molecular abnormalities may increase the susceptibility to inflammatory response of the gastric mucosa in H. pylori-infected patients and play an important role in the development of chronic active gastritis, atrophy, intestinal metaplasia, dysplasia and the intestinal type of gastric cancer. The severity of gastric mucosal damage correlates with the presence of mutations in the gastric mucosa and the age of patients.

Distribution of plantar pressure during jogging barefoot or in minimalistic shoes in people who used to run in cushioned shoes.

BACKGROUND: In recent years, an increasing number of runners prefer jogging barefoot or in minimalistic shoes. The aim of this study was to compare the distribution of plantar pressure during jogging barefoot, in minimalistic shoes, or in shoes with cushioned soles, as these forces modulate the risk of injury. METHODS: The study included nine men aged between 24 and 25 years, who engaged in long-distance running. The plantar pressure of three foot zones (forefoot, midfoot, and hindfoot) was examined with WIN-POD electronic podometer during running barefoot, in minimalistic shoes, or in shoes with cushioned soles. RESULTS: Individuals who ran barefoot showed the greatest forefoot pressure, followed by those running in minimalistic shoes and cushioned shoes. In contrast, the heel pressure in individuals running in cushioned shoes was significantly greater than in those using minimalistic shoes or running barefoot. CONCLUSIONS: Switching from running in cushioned shoes to jogging barefoot is associated with the accumulation of greatest pressure in the forefoot and midfoot. The accumulation of the greatest pressure at the insertion of plantar aponeurosis can lead to the injuries of musculoskeletal system, in particular plantar aponeurositis. Even distribution of pressure among various parts of the foot in persons running in minimalistic shoes is associated with lower risk of injury than in the case of running barefoot.

The effect of UGT1A9, CYP2B6 and CYP2C9 genes polymorphism on individual differences in propofol pharmacokinetics among Polish patients undergoing general anaesthesia.

Propofol (2,6-diisopropylphenol) is one of the safest and most commonly used anaesthetic agents for intravenous general anaesthesia. However, in clinical practice, a large inter-individual variability in response to propofol is observed. To limit the risk of adverse effects, pharmacogenetic investigations are recommended. The aim of our study was to verify the impact of genetic changes c.516G>T in the CYP2B6, c.98T>C in the UGT1A9 and c.1075A>C in the CYP2C9 genes on the individual propofol pharmacokinetic profile in the Polish patients undergoing general anaesthesia. Eighty-five patients from the Department of Anaesthesiology and Intensive Therapy, Regional Hospital in Poznan, Poland, anaesthetised with propofol for surgery, were enrolled in the study. We have genotyped CYP2B6, UGT1A9 and CYP2C9 polymorphisms with the use of pyrosequencing. HPLC measurements of propofol plasma concentration were applied for a pharmacokinetic analysis of the anaesthetic. We identified poor (20), intermediate (42) and rapid (23) metabolisers of propofol, which constituted 24%, 49% and 27% of the group, respectively. Homozygotes c.516 T/T in the CYP2B6 gene were statistically more often found in the rapid metabolisers group (p < 0.05). However, polymorphisms c.98T>C in the UGT1A9 and c.1075A>C in the CYP2C9 genes did not affect the pharmacokinetic profile of propofol. The mean propofol retention time (MRT) correlated with the patient's body mass index (BMI) (p < 0.05). From all the analysed changes, only polymorphism c.516G>T in the CYP2B6 gene and BMI affect the metabolism rate of propofol and may play an important role in the optimisation of propofol anaesthesia.

Analysis of the validity of assumptions underlying a research on the heritability of quantitative traits.

INTRODUCTION: Heritability is a statistical measure, expressing the proportion of phenotypic variance that is explained by the genetic variance. Heritability of a given trait can vary in time and may differ between populations, which is inter alia associated with interactions and correlations between genotype and environment or population-specific differences. Therefore, heritability measures are modulated by both genetic and environmental factors. Twin studies constitute one of the methods used to determine contributions of genes and environment to a given trait. However, studies of this type suffer from some methodological limitations and require certain conditions to be satisfied; both these factors were analyzed in the present study. MATERIAL AND METHODS: The studied material, including 1,263 pairs of male and female twins (among them 424 pairs of monozygotic twins and 839 pairs of dizygotic twins), born between the 22nd and 41st week of gestation, was collected at the Department of Perinatology and Gynecology, Poznan University of Medical Sciences, between 2002 and 2009. We analyzed the variance of six somatic traits. The contribution of genetic factors to the phenotypic variance of the studied twin population was estimated on the basis of the two heritability measures. RESULTS: Failure to meet the assumption of additivity of genetic and environmental effects probably is the cause of high values of heritability coefficients documented in our study. Analyzing the phenotypic variance of a trait, one cannot ignore the role of genotype-environment interactions and covariance, as these are their effects which increase the genetic variance and related coefficients of heritability. Therefore, it can be concluded that the genotypic component of the phenotypic variance of the trait is potentiated by the effects of various environmental factors. CONCLUSIONS: Our study confirmed that the critical remarks regarding the methodology of heritability estimation are fully justified. Consequently, the heritability indices of somatic traits should be considered only a provisional measure of genetic polymorphism, expressing an estimated relative contribution of genotypic variance to the phenotypic variance of a given trait.

Ecosensitivity and genetic polymorphism of somatic traits in the perinatal development of twins.

In view of criticism regarding the usefulness of heritability coefficients, the aim of this study was to analyze separately the information on genetic and environmental variability. Such an approach, based on the normalization of trait's variability for its value, is determined by the coefficients of genetic polymorphism (Pg) and ecosensitivity (De). The studied material included 1263 twin pairs of both sexes (among them 424 pairs of monozygotic twins and 839 pairs of dizygotic twins) born between the 22nd and 41st week of gestation. Variability of six somatic traits was analyzed. The zygosity of same-sex twins was determined based on the polymorphism of DNA from lymphocytes of the umbilical cord blood, obtained at birth. The coefficients of genetic polymorphism and ecosensitivity for analyzed traits of male and female twins born at various months of gestation were calculated. Our study revealed that a contribution of the genetic component predominated over that of the environmental component in determining the phenotypic variability of somatic traits of newborns from twin pregnancies. The genetically determined phenotypic variability in male twins was greater than in the females. The genetic polymorphism and ecosensitivity of somatic traits were relatively stable during the period of fetal ontogeny analyzed in this study. Only in the case of body weight, a slight increase in the genetic contribution of polygenes to the phenotypic variance could be observed with gestational age, along with a slight decrease in the influence of environmental factors.

A Simple Method for TPMT and ITPA Genotyping Using Multiplex HRMA for Patients Treated with Thiopurine Drugs.

Thiopurine methyltransferase (TPMT) and inosine triphosphatase (ITPA) are crucial enzymes involved in the metabolism of thiopurine drugs: azathioprine and 6-mercaptopurine, used in the treatment of leukemia or inflammatory bowel diseases (IBD). The activity in these enzymes correlates with the genetic polymorphism of the TPMT and ITPA genes, respectively, which determines an individual reaction and dosing of thiopurines. Three main TPMT alleles: TPMT*2 (c.238G>C), TPMT*3A (c.460G>A, c.719A>G) and TPMT*3C (c.719A>G) account for 80-95 % of inherited TPMT deficiency in different populations in the world. In the ITPA gene, a c.94C>A mutation is significantly associated with an adverse thiopurine reaction. The aim of this study was to develop a quick and highly sensitive method for determining major TPMT and ITPA alleles. Here we present the molecular test for genotyping c.238G>C, c.460G>A, c.719A>G and c.94C>A changes based on multiplex high resolution melting analysis (HRMA). We analyzed DNA samples from 100 clinically diagnosed IBD patients treated with thiopurine drugs, and a known genotype in the positions 238, 460 and 719 of the TPMT gene as well as in position 94 of the ITPA gene. Our results obtained with multiplex HRMA indicated 100 % accuracy in comparison with data from restriction fragments length polymorphism (RFLP) and standard DNA sequencing. We conclude, that multiplex HRMA can be used as a quick, sensitive and efficient alternative diagnostic method compared to conventional techniques for the determination of TPMT*2, TPMT*3A and TPMT*3C alleles and c.94C>A change in the ITPA gene.

Heritability estimates for somatic traits determined perinatally with the twin method.

The aim of this study was to establish estimates for heritability of somatic traits determined perinatally with the twin method. The studied material, including 1263 twin pairs live-born at various stages of prenatal life, i.e. between the 22nd and 41st week of gestation, was collected at the Department of Perinatology and Gynecology, Poznan University of Medical Sciences, between 2002 and 2009. The zygosity of 821 pairs of same-sex twins was determined at the Laboratory of Molecular Genetics in Poznan using analysis of single and multiple nucleotide polymorphisms. The proportion of phenotypic variance explained by genetic variability was determined using heritability indices based on intrapair variances and correlations. Analysis of these indices revealed that genetic variability predominated over environmental variability in determining the phenotypic variance of all studied traits. Heritability was the highest for body weight and shoulder width. The high values of heritability coefficients documented in our study were to a certain extent associated with an inconsistency of the assumption on the additive effect of genetic and environmental effects. While analyzing the phenotypic variance of a trait, the role of genotype-environment interactions and covariance cannot be ignored, as these are their effects which increase the genetic variance and related coefficients of heritability. Therefore, it can be concluded that the genotypic component of the phenotypic variance of the trait is enhanced by the effects of various environmental factors.

Sex dimorphism in development dynamics and in development progression of morphological features in human foetuses.

The study material comprised 3889 foetuses of both sexes, aged 20-42 weeks. t-Student test has been applied to evaluate the existence of potential sex-dependent differentiation of developmental trends as assessed by weekly measurements of selected somatic features and by the weight of internal organs. The regression coefficients of the analysed variables have been compared against the opposite sex. The rate of development of the analysed features in consecutive weeks has been found to be sex-related. Highest sex-related differences have been observed for the total body weight and for the weight of internal organs, with the exception of the adrenals, and the differences have been significant enough to justify the existence of contrasting, sex-dependent patterns of development of the analysed variables. The development of the analysed morphological features has been depicted by curvilinear regression. When described by various degree polynomials the development course of the analysed features displays sex-related differences. Only the change in the weight of the adrenals is similar for both sexes. The evaluation of the developmental advancement of the analysed features has revealed that they are usually at a more advanced development level in female foetuses.