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1.
The objective was to develop a novel and automated comprehensive framework for the non‐invasive identification and classification of kidney non‐rejection and acute rejection transplants using 2D dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI). The proposed approach consists of four steps. First, kidney objects are segmented from the surrounding structures with a geometric deformable model. Second, a non‐rigid registration approach is employed to account for any local kidney deformation. In the third step, the cortex of the kidney is extracted in order to determine dynamic agent delivery, since it is the cortex that is primarily affected by the perfusion deficits that underlie the pathophysiology of acute rejection. Finally, we use an analytical function‐based model to fit the dynamic contrast agent kinetic curves in order to determine possible rejection candidates. Five features that map the data from the original data space to the feature space are chosen with a k‐nearest‐neighbor (KNN) classifier to distinguish between acute rejection and non‐rejection transplants. Our study includes 50 transplant patients divided into two groups: 27 patients with stable kidney function and the remainder with impaired kidney function. All of the patients underwent DCE‐MRI, while the patients in the impaired group also underwent ultrasound‐guided fine needle biopsy. We extracted the kidney objects and the renal cortex from DCE‐MRI for accurate medical evaluation with an accuracy of 0.97 ± 0.02 and 0.90 ± 0.03, respectively, using the Dice similarity metric. In a cohort of 50 participants, our framework classified all cases correctly (100%) as rejection or non‐rejection transplant candidates, which is comparable to the gold standard of biopsy but without the associated deleterious side‐effects. Both the 95% confidence interval (CI) statistic and the receiver operating characteristic (ROC) analysis document the ability to separate rejection and non‐rejection groups. The average plateau (AP) signal magnitude and the gamma‐variate model functional parameter α have the best individual discriminating characteristics. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
2.
MLN4924 is an experimental cancer drug known as inhibitor of NEDD8-activating enzyme (NAE). This anti-tumor candidate is a selective small-molecule inhibitor of NAE which is conjugated to cullin protein on Cullin-RING ligases (CRLs). This covalent modification actives cullin complex to recruit an ubiquitin-charged E2 and leads to downstream target protein polyubiquitination and proteasomal degradation. MLN4924, which can form a covalent adduct with NEDD8, and block NAE at the first step in this pathway, has shown anti-tumor activity in many kinds of cancer cell lines and also xenograft models, including lung cancer, colon cancer, melanoma and lymphoma. The anti-tumor activity of MLN4924 results from inactivation of CLRs, which causes DNA re-replication and inhibition of nuclear factor (NF)-κB signaling, thus leading to cancer cell death. A mutation can reduce the enzyme’s sensitivity to MLN4924. Verma et al. in 2013 studied on molecular dynamics simulation of a mutant A171T and consequently found out that this mutation reduce MLN4924 interaction with DNA Binding site of enzyme as a result of reduction of enzyme affinity to ATP. One year later, in 2014, Wei Xu et al. carried out a research on inhibitor resistant cell lines and revealed that a couple of mutations so called Y352H and I310N leads to enzyme resistance to MLN4924 inhibitor, interestingly, the cause reported was the increase of enzyme affinity to ATP. As in Wei Xu et al. experiment the molecular dynamics simulation was not considered, present study is conducted to identify enzyme mutation mechanism by molecular dynamics approach using advantages of Gromacs software version 4.5.6.  相似文献   
3.
Lead is an old environmental metal which is presented everywhere and lead poisoning is an important health issue in many countries in the world including Iran. It is known as a silent environmental disease which can have life-long adverse health effects. In children, the most vulnerable population, mental development of children health effects is of the greatest influence. Low level lead exposure can significantly induce motor dysfunctions and cognitive impairment in children. The sources of lead exposure vary among countries. Occupational lead exposure is an important health issue in Iran and mine workers, employees of paint factories, workers of copying centers, drivers, and tile making factories are in higher risk of lead toxicity. Moreover lead processing industry has always been a major of concern which affects surface water, drinking waters, and ground waters, even water of Caspian Sea, Persian Gulf and rivers due to increasing the number of industries in vicinity of rivers that release their waste discharges into river or sea. In addition, lead contamination of soil and air especially in vicinity of polluted and industrialized cities is another health problem in Iran. Even foods such as rice and fishes, raw milk, and vegetables which are the most common food of Iranian population are polluted to lead in some area of Iran. Adding lead to the opium is a recently health hazard in Iran that has been observed among opium addicts. There are few studies evaluated current status of lead exposure and toxicity in the Iranian children and pregnant women which should be taken into account of authorities. We recommend to identify sources, eliminate or control sources, and monitor environmental exposures and hazards to prevent lead poisoning.  相似文献   
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6.

Introduction:

Survival sepsis campaign guidelines have promoted early goal-directed therapy (EGDT) as a means for reduction of mortality. On the other hand, there were conflicting results coming out of recently published meta-analyses on mortality benefits of EGDT in patients with severe sepsis and septic shock. On top of that, the findings of three recently done randomized clinical trials (RCTs) showed no survival benefit by employing EGDT compared to usual care. Therefore, we aimed to do a meta-analysis to evaluate the effect of EGDT on mortality in severe sepsis and septic shock patients.

Methodology:

We included RCTs that compared EGDT with usual care in our meta-analysis. We searched in Hinari, PubMed, EMBASE, and Cochrane central register of controlled trials electronic databases and other articles manually from lists of references of extracted articles. Our primary end point was overall mortality.

Results:

A total of nine trails comprising 4783 patients included in our analysis. We found that EGDT significantly reduced mortality in a random-effect model (RR, 0.86; 95% confidence interval [CI], 0.72–0.94; P = 0.008;   I2 =50%). We also did subgroup analysis stratifying the studies by the socioeconomic status of the country where studies were conducted, risk of bias, the number of sites where the trials were conducted, setting of trials, publication year, and sample size. Accordingly, trials carried out in low to middle economic income countries (RR, 0.078; 95% CI, 0.67–0.91; P = 0.002; I2 = 34%) significantly reduced mortality compared to those in higher income countries (RR, 0.93; 95% CI, 0.33–1.06; P = 0.28; I2 = 29%). On the other hand, patients receiving EGDT had longer length of hospital stay compared to the usual care (mean difference, 0.49; 95% CI, –0.04–1.02; P = 0.07; I2 = 0%).

Conclusion:

The result of our study showed that EGDT significantly reduced mortality in patients with severe sepsis and septic shock. Paradoxically, EGDT increased the length of hospital stay compared to usual routine care.  相似文献   
7.

Objective

The purposes of this study were; a) to compare multifidus muscle cross sectional area (CSA) in male adolescents suffering from low back pain (LBP) with healthy male adolescents using ultrasonography (US), and b) to assess the correlation between multifidus muscle size and demographic variables.

Methods

A random sample of 40 healthy boys (as a control group) and 40 boys with LBP (as an experimental group) at the age range of 15–18 years was recruited in the present cohort study. Multifidus muscle dimensions including CSA, antero-posterior and medio-lateral dimensions were measured at level of L5 in both groups using US.

Results

The results of an independent t-test to compare multifidus muscle size between the experimental and control groups showed a significant difference between the two groups in terms of CSA, antro-posterior and medio-lateral dimensions so that the experimental group had smaller muscle size than the control group. A significant correlation was found between height, weight and body mass index (BMI) and multifidus muscle size, but no significant correlation was observed between age and muscle size. Pain intensity and functional disability index was significantly correlated with muscle size in the experimental group.

Conclusions

According to the results, multifidus muscle size was decreased in 15–18 years old male adolescents suffering from LBP compared with their healthy counterparts. Further studies are needed to support the findings of the present study.  相似文献   
8.
The development of children over time is one of the continuing aims of psychological inquiry. Many studies have concluded that children who grew up in dysfunctional households show inconsistent development across various developmental pathways. Previous studies have consistently concluded how different family factors, such as interparents relationship, parent–child relationships, and emotional relations in families, can explain the outcomes of child behavior problems. Therefore, this paper attempts to review the empirical findings of previous studies that assess the effects of marital relations on child behavioral development by reviewing the literature that supports the association between marital relations and behavioral problems of children. Twenty-seven studies were chosen for their outcomes. This review used online databases such as Google Scholar, Scopus, ProQuest, Psychological and Behavioral Science collection, SAGE full-text collection in psychology, and PsycINFO. The key words used were marital relation, marital conflict, marital satisfaction, child behavior problem, and offspring behavior adjustment. All articles hypothesized that marital relation affects child adjustment and behavior outcomes directly and indirectly. Approximately all the research samples were in the developmental stage (ages 3 to 12). Various methodologies were used in the studies, but some methodological defects in the literature in some way diminished the interpretation of their findings. Results revealed that children who come from families high in conflict are at risk of psychopathological developmental problems in their adolescent years. This review adds to a large collection of literature that highlights the damaging effects of marital conflict on children. Research limitations and suggestions for future studies are outlined. The study provides a concrete basis for further research on this topic considering that married couples and child behavior problems are varied. This review can benefit married and soon-to-be married couples by revealing perceptions into the experiences of others as regards marriage problem solving.  相似文献   
9.

Purpose

To evaluate the total fluid intake from drinking water and beverages in adult populations from different countries and assess the percentage of individuals complying with the European Food Safety Agency (EFSA) adequate intake (AI) of water from fluids.

Methods

A total of 16,276 adults (7580 men and 8696 women) aged between 18 and 70 years (mean age 39.8 years) were randomly recruited from 13 different countries from three continents. Information about the total daily fluid intake (sum of drinking water and beverages) was collected using a 24-h fluid-specific record over seven consecutive days.

Results

Important differences in total fluid intake between countries were found; however, few differences between men and women were reported in most of the countries. Less than 50 % of the women and approximately 60 % of the men do not comply with the EFSA AI of water from fluids. Women were more than twice as likely as men to meet these AI (OR 2.15; 95 % CI 2.02–2.29). The odds of meeting the AI of water from fluids were lower in individuals over 50 years (OR 0.88; 95 % CI 0.80–0.96). Nine percent of the total population consumed less than half of the AI, 40.5 % between 50 and 100 %, and 50.5 % more than the AI.

Conclusions

There were considerable differences in total fluid intake between countries but not between genders. Only 40 % of men and 60 % of women comply with the EFSA AI of water from fluids. Men and elderly individuals had an increased risk of not complying with this reference value.
  相似文献   
10.

Purpose

To describe total fluid intake (TFI) according to socio-demographic characteristics in children and adolescents worldwide.

Methods

Data of 3611 children (4–9 years) and 8109 adolescents (10–18 years) were retrieved from 13 cross-sectional surveys (47 % males). In three countries, school classes were randomly recruited with stratified cluster sampling design. In the other countries, participants were randomly recruited based on a quota method. TFI (drinking water and beverages of all kinds) was obtained with a fluid-specific record over 7 consecutive days. Adequacy was assessed by comparing TFI to 80 % of adequate intake (AI) for total water intake set by European Food Safety Authority. Data on height, weight and socio-economic level were collected in most countries.

Results

The mean (SD) TFI ranged from [1.32 (0.68)] to [1.35 (0.71)] L/day. Non-adherence to AIs for fluids ranged from 10 % (Uruguay) to >90 % (Belgium). Females were more likely to meet the AIs for fluids than males (4–9 years: 28 %, OR 0.72, p = 0.002; 10–18 years: 20 %, OR 0.80, p = 0.001), while adolescents were less likely to meet the AI than children (OR 1.645, p < 0.001 in males and OR 1.625, p < 0.001 in females).

Conclusions

A high proportion of children and adolescents are at risk of an inadequate fluid intake. This risk is especially high in males and adolescents when compared with females or children categories. This highlights water intake among young populations as an issue of global concern.
  相似文献   
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