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101.
The aim of this report is to determine frequencies and associations of p53 codon 72 arg/pro polymorphism with different types of cancer in Sudan. p53 codon72 arg/pro polymorphism distribution and allele frequencies in 264 samples of different types of cancers were investigated using PCR. The results were compared to 235 normal controls. The results indicated significant differences in frequency and genotype association between different types of cancers. Breast carcinoma patients most prominently showed excess of homozygous arg genotype as compared to controls with an Odd ratio (OR) of 19.44, 95?%CI: 6.6–78.3, P?<?0.0001. Less prominently cervical cancer showed genotype effect of 2.4 OR, 95?%CI: 1.12–5.33, P?=?0.015, while esophageal cancer had an OR of 0.57, 95?%CI: 0.23–1.42, P?=?0.1. In Burkitt’s lymphoma, however, in contrast the homozygous arg accounted for only 6.9?%, (OR 0.18, 95?%CI: 0.02–0.89, P?=?0.018). We concluded that p53 arg/pro polymorphism has different pattern of frequency in different types of cancer among Sudanese patients, indicating perhaps different etiology and biology of these tumours.  相似文献   
102.
Natural killer (NK) cells play an essential role in the immune response to infections, inflammations, and malignancies. Recent studies suggest that NK cell surface receptors and cytokines are the key points of the disease development and protection. We hypothesized that the interactions between NK cell receptors and targeted cells construct an eventual niche, and this niche has an eventual profile in various autoimmune diseases and cancers. The NK cells preactivated with cytokines, such as interleukin-2 (IL-2), IL-12, IL-15, and IL-18 can have higher cytotoxicity; however, the toxic side effect of IL-2 should be considered. The vicissitudes of NK cell profile and its receptors obey the environmental communications and cell interactions. Our vision around the NK cells as an immune axis remained dual, and we still cannot judge the immune responses based on the NK cell flip-flop. A design of eventual niche to monitor the NK cell and targeted cell interaction is needed to strengthen our ability in diagnosis and treatment approaches based on the NK cells. Here, we have reviewed the shifts in the NK cells and their surface receptors in autoimmune diseases, solid tumors, and leukemia, and also discussed the effective chemokines that affect NK cell activation and proliferation. The main aim of this review is to present a broader vision of the NK cell changes in autoimmune disease and cancers.  相似文献   
103.
104.
CD8+ cytotoxic T lymphocytes (CTL) and natural killer cells are the main cytotoxic killer cells of the human body to eliminate pathogen-infected or tumorigenic cells (also known as target cells). To find their targets, they have to navigate and migrate through complex biological microenvironments, a key component of which is the extracellular matrix (ECM). The mechanisms underlying killer cell’s navigation are not well understood. To mimic an ECM, we use a matrix formed by different collagen concentrations and analyze migration trajectories of primary human CTLs. Different migration patterns are observed and can be grouped into three motility types: slow, fast, and mixed. The dynamics are well described by a two-state persistent random walk model, which allows cells to switch between slow motion with low persistence and fast motion with high persistence. We hypothesize that the slow motility mode describes CTLs creating channels through the collagen matrix by deforming and tearing apart collagen fibers and that the fast motility mode describes CTLs moving within these channels. Experimental evidence supporting this scenario is presented by visualizing migrating T cells following each other on exactly the same track and showing cells moving quickly in channel-like cavities within the surrounding collagen matrix. Consequently, the efficiency of the stochastic search process of CTLs in the ECM should strongly be influenced by a dynamically changing channel network produced by the killer cells themselves.  相似文献   
105.
Plasmonics - Detection of diphtheria toxin (DT) which is produced by Corynebacterium diphtheria, a zoonotic pathogen and a leading cause of diphtheria, is the critical step in the clinical...  相似文献   
106.

Objective

Using genetic markers and miRs work strongly beside other sensitive biomarkers in lupus management during sensitive period of pregnancy.

Methods

PubMed and Google Scholar databases were searched from 2000 to 2017 using the terms “lupus,” “lupus pregnancy,” “biomarkers,” “micro-RNA,” “polymorphisms,” “anti-phospholipid antibodies,” and “cluster differentiation markers.”

Discussion

Complement is a valuable biomarker in lupus pregnancy. However, the complement profile has ambiguous meaning because decreased levels of C3 and C4 reflect inflammation and because they are also prognostic biomarkers for abortion. Furthermore, increased C3 and C4 levels indicate hepatic protein synthesis in hepatocytes. Anti-phospholipid (APL) antibodies are present in 25% to 50% of lupus patients, and can lead to thrombotic and obstetric complications in some pregnancies and increase the risk of abortion, especially in a pregnant woman in the active phase of lupus. Several studies have associated APL with HELLP syndrome. However, other pregnancy complications have not been associated with APL. Autoantibodies against the major vault protein and anti-double strand DNA antibodies are valuable biomarkers in evaluating lupus activity. The expression pattern of micro-RNAs (miRs) differs in various diseases. Current studies have demonstrated the potential of miRs as diagnostic and prognostic biomarkers in various diseases; for example, the level of miR-126 is higher in lupus.

Conclusion

Mir-223-3p and miR-451 are informative biomarkers in estimating disease activity. TWEAK, BAFF, and APOL1 genes, and their polymorphisms are informative in estimating disease activity, especially renal effects, and in monitoring higher-risk pregnant women. Further studies of these genes and their relevant polymorphisms are needed.
  相似文献   
107.
Six sesquiterpene lactones were isolated from the aerial parts of Ambrosia maritima. Four pseudoguaianolides were isolated for the first time in addition to parthenin and neoambrosin.  相似文献   
108.

Objectives

Thrombotic episodes occurred frequently in beta-thalassemia major (BTM) patients, leading to hypercoagulability of plasma. Protein Z (PZ) is a vitamin-K-dependent anti-coagulation factor that plays a role in the human homeostatic process. The objective of the current study is to investigate the distribution pattern of PZ plasma concentrations between BTM patients and the normal population in Ahvaz city, the center of Khuzestan province, southwest of Iran.

Material and Methods

Forty confirmed BTM patients and 40 healthy volunteers were evaluated for complete blood count (CBC) indices and PZ plasma levels. CBC samples were measured using an automated cell counter, and PZ was assayed with an immunoassay method. Statistical analysis was conducted using SPSS software. The ROC curve and binary logistic regression estimated the sensitivity, specificity, and Odd’s ratio for PZ measurement.

Results

The mean±SD of the PZ plasma level in normal individuals was 1.68±0.63 μg/mL, and in BTM patients, it was 1.10±0.52 μg/mL. This shows a significant reduction of PZ in BTM patients statistically (CI = 0.99; p<0.001). Further, the mean±SD of the PZ plasma levels in BTM patients who received washed red blood cells was not significantly different from that of patients undergoing packed red blood cell therapy (CI = 0.95; p = 0.320). The area under the curve (AUC) for PZ was 0.759 (p = 0.00). The cut-off value = 1.4 μg/mL of the PZ plasma level had at least 70% sensitivity and specificity in BTM patients.

Discussion

Several epidemiologic studies have shown thromboembolism episodes in BTM patients. In the current study, PZ was reduced significantly in BTMs.

Conclusion

We noticed that BTMs have lower plasma PZ concentration might be predisposed to BTM.
  相似文献   
109.
Background:Sepsis is one of the most common causes of multiorgan failure. Sepsis requires the presence of infection with a resultant systemic inflammatory state. Organ dysfunction occurs from the combination of the two processes. Sepsis is the main cause of mortality at intensive care units, with 30-50% mortality rate for all septic episodes. MicroRNA (miRNA) profile data could be beneficial as a specific diagnostic biomarker for sepsis and systemic inflammatory response syndrome (SIRS).Methods:Expression of miRNAs -122, -181b, -223 and -146a levels were assayed by quantitative real time polymerase chain reaction (qRT-PCR) in a prospective case control study, where forty septic cases were compared to 40 healthy controls of matched age and gender. Results:miRNAs -122 and -181b were significantly upregulated during early septic conditions, indicating that they could be sensitive and specific biomarkers for diagnosing sepsis. miRNA-223 and miRNA-146a could also represent highly specific and sensitive diagnostic biomarkers, as they were found to be significantly down-regulated. Serum levels of miRNA-223 could be used to predict poor prognosis with 70% sensitivity and 75% specificity, whereas the other three miRNAs could not predict prognosis.Conclusion:Our study shows that all tested miRNAs can be used for early detection of sepsis, with miRNA-223 being predictive of mortality, hence preventing multi-organ failure and reducing mortality, and predicting poor outcomes, thereby assisting in early categorization of ICU patients for rapid appropriate treatment and medico legal aspects.Key Words: Micrna-223, Systemic inflammatory response syndrome (SIRS), Sepsis, Biomarker  相似文献   
110.
Morningness-Eveningness Stability Scale improved (MESSi) is a newly constructed measure to assess circadian types and amplitude. In this study, we applied this measure to participants from three different countries: Germany, Spain and Iran. Confirmatory factorial analysis (CFA) of MESSi displayed mediocre fit in the three countries. Comparing increasingly stringent models using multigroup confirmatory factor analyses indicated at least partial measurement invariance (metric invariance) by country for Morning Affect and Distinctness subscales. Age was positively related to Morning Affect (MA), and negatively related to Eveningness (EV) and Distinctness (DI). Men reported higher MA than women, whereas women reported higher DI than men. Regarding country effect, Iranian participants reported highest MA compared to Spaniards and Germans, whereas Germans reported higher DI compared to Iranians and Spaniards. As a conclusion, our study corroborated the validity and reliability of MESSi across three different countries with different geographical and cultural characteristics.  相似文献   
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