Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels

While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer coupling model to explore the interactions between information and disease.The upper layer describes the diffusion of disease-related information,and the lower layer represents the disease transmission.We then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the network.Subsequently,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical results.Our findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion layer.Moreover,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease control.This study provides valuable insights into policymakers for developing outbreak prevention and control strategies.

ENSO Index Variations and Links with Solar and Volcanic Activity

In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations.

Terrestrial Temperature, Sea Levels and Ice Area Links with Solar Activity and Solar Orbital Motion

This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere.

Magnetic cycles of Sun-like stars with different levels of coronal and chromospheric activity——comparison with the Sun

The atmospheric activity of the Sun and Sun-like stars is analyzed involving observations from the HK-project at the Mount Wilson Observatory, the California and Carnegie Planet Search Program at the Keck and Lick Observatories and the Magellan Planet Search Program at the Las Campanas Observatory. We show that for stars of E G and K spectral classes, the cyclic activity, similar to the 11-yr solar cycle, is different： it becomes more prominent in K-stars. Comparative study of Sun-like stars with different levels of chromospheric and coronal activity confirms that the Sun belongs to stars with a low level of chromospheric activity and stands apart among these stars by its minimum level of coronal radiation and minimum level of variations in photospheric flux.

Mediating role of physical activity in the relationship between psychological distress and intimate relationships among stroke patients

BACKGROUND Stroke patients often experience psychological distress,which can impact their intimate relationships with spouses,subsequently influencing their treatment and recovery.Physical activity is considered a key rehabilitation method for stroke patients.This paper aims to analyze whether psychological distress affects intimate relationship between spouses through physical activity.AIM To explore the mediating effect of physical activity between psychological distress and intimate relationship in stroke patients.METHODS A total of 256 stroke patients who underwent treatment at the First People’s Hospital of Shangqiu between July 2021 and July 2022 were enrolled in this study.The participants completed questionnaires,including the Kessler Psychological Distress Scale(K10),the Quality of Relationship Index(QRI),International Physical Activity Questionnaire,and a general information questionnaire.Data analysis were performed using SPSS 23.0.The Harman test was employed to detect common method deviations,and Spearman correlation was used for correlation analysis.The mediating effect was assessed using Process 3.4.1,with significance testing of the regression coefficients conducted using the bias-corrected percentile Bootstrap method(5000 iterations,95%confidence interval).Statistical significance was set at P<0.05.RESULTS The results showed that patients scored an average of 21.61±6.44 points on the K10,32.40±6.19 points on the QRI;the median physical activity level according to the International Physical Activity Questionnaire was 1861(566,2846)MET·min/w.The level of physical activity(the physical activity intensity of the patients reflected by the Interna-tional Physical Activity Questionnaire-Long Form scale)negatively correlated with psychological distress and intimacy(P<0.05),and positively correlated with each other(P<0.05),with the correlation stronger at lower physical activity levels compared to higher ones.The mediating effect of physical activity between psychological distress and intimate relationship was calculated to be 40.23%.Bootstrap analysis further validated the results.The mediating effect of psychological distress on intimate relationships through physical activity level was-0.284,with a confidence interval of-0.409 to-0.163,excluding 0,confirming a significant mediating effect of psychological distress on intimate relationships.CONCLUSION Physical activity significantly affects relationship between psychological distress and intimate relationships among stroke patients.Addressing the role of physical activity may have implications for improving patient outcomes and rehabilitation strategies.

Prediction of Short Stellar Activity Cycles using Derived and Established Empirical Relations between Activity and Rotation Periods

In our previous work,we investigated the occurrence rate of super-flares on various types of stars and their statistical properties,with a particular focus on G-type dwarfs,using entire Kepler data.The said study also considered how the statistics change with stellar rotation period,which in turn,had to be determined.Using such new data,as a by-product,we found 138 Kepler IDs of F-and G-type main sequence stars with rotation periods less than a day(P_(rot)<1 day).On one hand,previous studies have revealed short activity cycles in F-type and G-type stars and the question investigated was whether or not short-term activity cycles are a common phenomenon in these stars.On the other hand,extensive studies exist which establish an empirical connection between a star's activity cycle and rotation periods.In this study,we compile all available Kepler data with P_(rot)<1 day,and rely on an established empirical relation between P_(cyc)and P_(rot)with the aim to provide predictions for very short 5.09≤P_(cyc)≤38.46 day cases in a tabular form.We propose an observation to measure P_(cyc)using a monitoring program of stellar activity(e.g.,activity-related chromospheric emission S-index)or a similar means for the Kepler IDs found in this study in order put the derived empirical relations between P_(cyc)and P_(rot)derived here to the test.We also propose an alternative method for measuring very short P_(cyc),using flare-detection algorithms applied to future space mission data.

Chromospheric activity in several single late-type stars

New high-resolution echelle spectra of six single late-type Pleiades-like stars （V368 Cep, EP Eri, DX Leo, GJ 211, PW And and V383 Lac） were obtained with the 2.16 meter telescope at Xinglong Station in 2008-2010. Using the spectral subtraction technique, we analyzed our spectroscopic data and calculated the equiva- lent widths of excess emission from several indicators of chromospheric activity （Na I D1, D2, Hoz and Ca II infrared triplet lines）. All our results using chromospheric activ- ity indicators confirmed the previous findings. In addition, the maximum amplitudes of chromospheric rotational modulation and the ratio of EW8542/EW8498 were found to rise with increasing v sin i velocity.

Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels

Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy.

Evolution of the Level of Sunspot Activity in Solar Cycles I. Evolution in the Descending Phase

Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 22. Our results show （1） for 46 months （94%） of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months （73%） the fitting is even better, for a = 1%; （2） time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; （3） the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.291.

Diagnostic value of plasminogen activity level in acute mesenteric ischemia

AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) the superior mesenteric artery (SMA) and vein (SMV) were explored, but not tied. In SMA groups (Groups Ⅲ and Ⅳ) the SMA was ligated, and in SMV groups (Groups Ⅴ and Ⅵ) the SMV was ligated. On re-laparatomy 2 mL of blood was drawn at 1 h in groupsⅠ, Ⅲ and Ⅴ, and at 3 h in groups Ⅱ, Ⅳ and Ⅵ. Plasminogen levels were assessed and comparisons were made between groups and within each group. RESULTS: The mean plasminogen activity in the SL group was significantly higher than SMA (25.1 ± 10.8 vs 11.8 ± 4.6, P < 0.001) or SMV (25.1 ± 10.8 vs 13.7 ± 4.4, P < 0.001) groups both at 1 h and at 3 h (29.8 ± 8.9 vs 15.1 ± 5.7, P < 0.0001; 29.8 ± 8.9 vs 14.2 ± 2.9, P < 0.0001). There were no significant differences between the values of SMA and SMV groups at 1 h (P = 0.28) and at 3 h (P = 0.71). In each group, plasminogen activity levels did not change significantly between the two measurements performed at 1 h and 3 h. CONCLUSION: We conclude that blood plasminogen activities decrease during early phases of both arterial and venous mesenteric ischemia which may be a useful marker for early diagnosis.

Antiepileptic activity of lobeline isolated from the leaf of Lobelia nicotianaefolia and its effect on brain GABA level in mice

Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid(GABA)in brain of mice in Pentylenetetrazol(PTZ) seizure models.Methods:The anticonvulsant activity of the isolated lobelinc(5,10,20 and 30 mg/kg.i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lolieline on brain GABA level in seizures induced by PTZ.Diazepam was used as reference anticonvulsant drugs for comparison.Results:Isolated lobeliue(10,20 and 30 nig/kg.up.) significautly delayed and antagonized(P < 0.050-0.001)the onset of PTZ-induced seizures.It also antagonized strychnine induced seizures.The mortality was also prevented in the test group of animals.In biochemical evaluation,isolated lolieline(5,10and 20 mg/kg,i.p.) significantly increased the brain GABA level.And at dose of 30 mg/kg GABA level showed slight decrease in PTZ model.Conclusions:In our findings,isolated lolieline(20mg/kg) exhibited potent anticonvulsant activity against PTZ induced seizures.Also a biochemical evaluation suggested significant increase in harain GABA level at 20 nig/kg up.of isolated lolieline.Hence,we may propose that lolieline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism.

Multiple cycles of magnetic activity in the Sun and Sun-like stars and their evolution

The wavelet transform method for high-quality time-frequency analysis is applied to sets of observations of relative sunspot numbers and stellar chromosphere fluxes of 10 Sun-like stars. Wavelet analysis of solar data shows that in a certain interval of time there are several cycles of activity with pe- riods of duration which vary considerably from each other： from quasi-biennial cycles to lO0-yr cycles. Cyclic activity was detected in almost all Sun-like stars that we examined, even those that previously were not considered as stars with cyclic activity according to analysis using a Scargle periodogram. The durations of solar and stellar cycles significantly change during the observation period.

Body Composition, Dietary Intake and Physical Activity Level of Sedentary Adult Indian Women

Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well as dietary intake. The study was designed to assess the body composition, dietary intake and physical activity level of sedentary adult women of different age groups. A cross-sectional study was conducted on 152 sedentary adult women comprised of students and faculty from Punjab Agricultural University, Ludhiana. The relationship of body composition with dietary factors and physical activity level of women in four age groups i.e. 21 - 30, 31 - 40, 41 - 50 and 51 - 60 years was determined. A gradual increase (p ≤ 0.05) in anthropometric and body composition parameters such as weight, waist circumference, hip circumference, body mass index, fat mass and visceral fat rating was observed with the advancement of age. The lean body mass was decreased significantly (p ≤ 0.05) as the age progressed, the values for four age groups being 74.9, 68.9, 62.8 and 60.9%, respectively. Contrary to this fat mass increased with age, the corresponding values for four age groups being 15.7, 21.4, 26.6 and 29.2 kg, respectively. The percent adequacy of protein by four age groups was 69.6, 78.2, 80.0 and 66.3, respectively when compared to RDA while fat intake was much higher i.e. 245.5, 271.8, 288.4 and 250.8%, respectively. The energy intake was inadequate among all age groups, however, a significant (p ≤ 0.05) differ- ence was observed in daily energy consumption between the age groups. The mean physical activity level (PAL) of the subjects ranged between 1.49 - 1.60. The physical activity level values showed that majority of the subjects (87% - 94%) were having sedentary life style. Age is a crucial factor associated with body composition. A high fat mass and low lean body mass of the subjects was observed. Their diets were low in protein but high in fat. Majority of the subjects from different age groups had sedentary life style. A diet with higher protein and lesser fat combined with exercise can help in sustaining optimum body composition.

A study of the global magnetic activity of the star Kepler-17 using light curve inversion with bipartite regularization

A new method of light curve inversion with bipartite regularization(LIBR),which is complementary to the previous treatments by Bonomo and Lanza and Estrela and Valio,is used to reconstruct the physical properties of star spots on the solar-type star Kepler-17 by using the full Q1-Q17 data set.The Markov Chain Monte Carlo(MCMC)method was applied to find the best profile of the reconstructed surface.The known value of the rotation inclination of Kepler-17 allows the generation of a star spot model in a sequence of stellar rotation with a period of 12.26 d.Because of the nature of the light curve inversion,the spot model is limited to the equatorial region.We also investigated the starspot lifetimes of Kepler-17 utilizing the MCMC method.Combined with the LIBR inversion results,it was found that the star spots typically last from one to several stellar rotations.From the time evolution of the spot size,a magnetic cycle period of 437 d can be derived.This value is comparatively shorter than the solar cycle which might be a consequence of the younger age(~1.78 Gyr)of Kepler-17.The light curve of Kepler-17 is characterized by the presence of large-amplitude variation caused by star spots but no superflare activity.An interesting possibility is that the magnetic energy stored in the star spot regions could have been constantly dissipated by electrodynamic interaction between the central star and the hot Jupiter,Kepler-17 b,via a lower-level energy release process.

Effects of Physical Activity Levels on Fatigue Perception in Patients with Parkinson’s Disease and Neurologically Healthy Individuals

Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels;and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity.

The Physical Properties and Starspot Activity of the Triple System KIC 6525196

We present the results of photometric and spectroscopic analyses for the triple-lined system KIC 6525196,an eclipsing binary accompanied by a third star.By modeling the Kepler light curves and radial velocities from LAMOST and HIDES observations,absolute parameters of the system are determined.Both components of the eclipsing binary are found to be solar-like stars with masses and radii of M= 1.0286 ± 0.0026 M,R= 1.127 ± 0.008 R.and M=0.9667 ± 0.0024 M,R=0.963 ± 0.007 R.The mass of the third star is determined to be M= 0.772 ± 0.010 M.With the out-of-eclipse light residuals,we measure rotation period and decay timescale of an active region by using the autocorrelation function.In comparison to the Sun,the activity level of the system is significantly stronger.In addition,a possible short photometric activity cycle of~244 days is detected.

Physical Activity Level and Adult Saudi Health Related Quality of Life

Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi health-related quality of life (HRQoL). Methods: Participants of this study were 100 Saudi adult aged from 18 - 70 years. The 36-Item Short-Form Health Status Survey (SF-36) was used to measure the participant’s HRQoL. The SF-36 is comprised of 8 domains. The electronic version of the General Practice Physical Activity Questionnaire was used to categorize participants in terms of physical activity level into;inactive, moderately inactive, moderately active, and active. Descriptive and inferential statistical tests were used to treat the collected data. Results: Results showed that only 17% of the Saudi adults had active PAL. The PAL had significantly positive relationship with 4 domains of HRQoL including: physical functioning (P = 0.004), role limitations caused by physical health problems (P = 0.048), vitality (P = 0.009), and general health (P = 0.044). Results also confirmed that the younger the subject, the higher the PAL (P = 0.0001) and the better the HRQoL. This is true for all domains except the role limitations caused by emotional problems and emotional wellbeing. Conclusion: The poor physical activity level of adult Saudi negatively impacts their HRQoL.

Chromospheric activity on the late-type star V1355 Ori using Lijiang 1.8-m and 2.4-m telescopes

We obtained new high-resolution spectra using the Lijiang 1.8-m and 2.4-m telescopes to inves- tigate the chromospheric activities of V1355 Ori as indicated in the behaviors of Ca n H＆K, Hγ HT, H/3, Na1 D1, D2, Ha and Ca II infrared triplet （IRT） lines. The observed spectra show obvious emissions above the continuum in Ca II H＆K lines, absorptions in the Hδ, Hγ, H/3 and NaI D1, D2 lines, variable behavior （filled-in absorption, partial emission with a core absorption component or emission above the continuum） in the Ha line, and weak self-reversal emissions in the strong filled-in absorptions of the Ca II IRT lines. We used a spectral subtraction technique to analyze our data. The results show no excess emission in the H6 and H7 lines, very weak excess emissions in the Na I D1, D2 lines, excess emission in the H/3 line, clear excess emission in the Ha line, and excess emissions in the Ca II IRT lines. The value of the ratio of EWs542/EWsa9s is in the range 0.9 to 1.7, which implies that chromospheric activity might have been caused by plage events. The value of the ratio EHδ/EHβ is above 3, indicating that the Balmer lines would arise from prominence-like material. We also found time variations in light curves associated with equiva- lent widths of chromospheric activity lines in the Na I D1, phenomena can be explained by plage events, which are activity indicators. D2, Ca II IRT and Ha lines in particular. These consistent with the behavior of chromospheric

What Is the Relation between Aerobic Capacity and Physical Activity Level in Adults with Congenital Heart Disease?

Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the association between PA level and AC(measured as peak of oxygen consumption,VO_(2peak))in adults with CHD.Methods:A total of 183 individuals(83 women and 100 men;mean(SD)age 36.9(11.0)years old)from Vall d’Hebron Hospital,Barcelona-Spain in 2019,participated in this cross-sectional study.The AC was assessed by cardiopulmonary exercise testing(CPET)using a treadmill ramp protocol.Considering values of metabolic equivalent of task(MET,MET-min·week-1)obtained by the short International Physical Activity Questionnaire(IPAQ),participants were divided into three categories of PA:health-enhancing PA(HEPA),minimally active,and inactive.Results:Median(SD)PA was 2737.2(2835.7)MET-min·week-1,with 60 participants(32.8%)reporting HEPA,91(49.7%)minimally active,and 32(17.5%)inactivity.Participants demonstrated a mean VO_(2peak) of 28.9(8.8)mL·Kg^(-1)·min^(-1),showing AC values on average 13%lower than expected in a healthy population.Overall,PA and AC were positively associated.Adjusting for sex and age,an increase of 1000 MET-min·week^(-1) was associated with an increase in VO_(2peak) of 0.8 units(95%CI 0.4–1.2;p<0.001).There were no differences in the degree of increase between sexes(p=0.427).Conclusion:These findings suggest that an increase in PA in patients with CHD significantly improves their AC,and hence,could be recommended when the goal is to improve their physical condition.

A study of the relationship between expression level of TRF1 protein and telomerase activity in human acute leukemia

Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase. Methods: A quantitative Western-Blot technique was developed using anti-TRF133-277 monoclonal antibody and GST-TRF1 purity protein as a standard to further determine the ex-pression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors’ bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P<0.01) in normal bone marrow ((2.217±0.462) μg/μl) than that of acute leukemia patients ((0.754±0.343) μg/μl). But there was no remarkable difference between ALL and ANLL patients ((0.618±0.285) μg/μl vs (0.845±0.359) μg/μl, P>0.05). After chemotherapy, TRF1 expression level of patients with complete remission elevated ((0.772±0.307) μg/μl vs (1.683±0.344) μg/μl, P<0.01), but lower than that of normal ((2.217±0.462) μg/μl, P<0.01). There was no significantly difference after chemotherapy ((0.726±0.411) μg/μl vs (0.895±0.339) μg/μl, P>0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1.683±0.344) μg/μl vs (0.895±0.339) μg/μl, P<0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284) μg/μl, P<0.01). There was no significant difference of expression level of TRF1 protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P>0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P<0.01). Conclusion: The expression level of TRF1 protein has corre-lativity to the activity of telomerase (P<0.001).