首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 8 毫秒
1.
As the primary microtubule organizing center of most eukaryotic cells, centrosomes play a fundamental role in proper formation of the mitotic spindle and subsequent chromosome separation. Normally, the single centrosome of a G1 cell duplicates precisely once prior to mitosis in a process that is intimately linked to the cell division cycle via cyclin-dependent kinase (cdk) 2 activity that couples centrosome duplication to the onset of DNA replication at the G1/S transition. Accurate control of centrosome duplication is critical for symmetric mitotic spindle formation and thereby contributes to the maintenance of genome integrity. Numerical and structural centrosome abnormalities are hallmarks of almost all solid tumors and have been implicated in the generation of multipolar mitoses and chromosomal instability. In addition to solid neoplasias, centrosome aberrations have recently been described in several different hematological malignancies like acute myeloid leukemias, myelodysplastic syndromes, Hodgkin's as well as non-Hodgkin's lymphomas, chronic lymphocytic leukemias and multiple myelomas. In analogy to many solid tumors a correlation between centrosome abnormalities on the one hand and karyotype aberrations as well as clinical aggressiveness on the other hand seems to exist in myeloid malignancies, chronic lymphocytic leukemias and at least some types of non-Hodgkin's lymphomas. Molecular mechanisms responsible for the development of centrosome aberrations are just beginning to be unraveled. In general, two models with distinct functional consequences can be envisioned. First, centrosome aberrations can arise as a consequence of abortive mitotic events and impaired cytokinesis. Second, evidence has been provided that centrosome amplification can also precede genomic instability and arise in normal, diploid cells. Accordingly, this review will focus on recent advances in the understanding of both, causes and consequences of centrosome aberrations in hematological malignancies.  相似文献   

2.
3.
4.
ObjectiveAdolescents and young adults (AYA) with cancer are confronted with unique challenges in areas of paramount concern within their age group, such as fertility, education, career, and delayed and long-term effects of treatment. However, the extent and depth of the problem has never been examined in the Japanese population. The aim of this study was to describe the status of cancer patients in the AYA population, using data from the hospital-based cancer registry (HBCR).Study designPatients included in the HBCR from January 2011 to December 2014 were included in this study to evaluate the incidence and cancer distribution trends among AYA. The total number and the proportion of AYA (15–39 years of age) stratified by sex, age, and cancer type were obtained. The incidence of age-specific cancer among AYA was also calculated.ResultsWe identified 30,394 male (35.1%) and 56,100 female (64.9%) cancer patients in the population, which collectively constituted about 3% of all invasive cancer cases. The incidence of cancer in AYA was estimated as 86.2 per 100,000 per year, and increased with age. The most affected population was women between 35 and 39 years of age (35%). Breast cancer was the most common type of cancer, followed by cervical, uterine, and thyroid cancers.ConclusionA substantial number of AYA are diagnosed with cancer every year. The distribution of cancer types in AYA was dependent on age and sex. These diversities in cancer types can inform researchers and policy makers to fine-tune their studies and policies.  相似文献   

5.
Allogeneic bone marrow transplant is a life-saving procedure for adults and children that have high-risk or relapsed hematological malignancies. Incremental advances in the procedure, as well as expanded sources of donor hematopoietic cell grafts have significantly improved overall rates of success. Yet, the outcomes for patients for whom suitable donors cannot be found remain a significant limitation. These patients may benefit from a hematopoietic cell transplant wherein a relative donor is fully haplotype mismatched. Previously this procedure was limited by graft rejection, lethal graft-versus-host disease, and increased treatmentrelated toxicity. Recent approaches in haplo-identical transplantation have demonstrated significantly improved outcomes. Based on years of incremental preclinical research into this unique form of bone marrow transplant, a range of approaches have now been studied in patients in relatively large phase Ⅱ trials that will be summarized in this review.  相似文献   

6.
血液肿瘤作为一类常见恶性肿瘤疾病主要包括各类白血病、多发性骨髓瘤以及恶性淋巴瘤.随着现代社会高速发展,人群发病率呈逐年升高趋势,且发病年龄逐渐低龄化,发病原因与环境因素以及遗传因素密不可分.近年来研究发现,表观遗传学修饰在血液肿瘤发生发展的过程中扮演了重要角色,一些相关修饰基因作为血液肿瘤的治疗靶点在临床应用上取得了重要进展.针对近年来表观遗传学修饰在血液肿瘤中的研究新进展,本文将系统综述DNA甲基化、组蛋白修饰、非编码RNA及RNA修饰等在血液肿瘤发病机制方面的研究进展.  相似文献   

7.
The phosphatases of regenerating liver (PRLs), consisting PRL1, PRL2 and PRL3, are dual-specificity protein phosphatases that have been implicated as biomarkers and therapeutic targets in several solid tumors. However, their roles in hematological malignancies are largely unknown. Recent findings demonstrate that PRL2 is important for hematopoietic stem cell self-renewal and proliferation. In addition, both PRL2 and PRL3 are highly expressed in some hematological malignancies, including acute myeloid leukemia (AML), chronic myeloid leukemia (CML), multiple myeloma (MM) and acute lymphoblastic leukemia (ALL). Moreover, PRL deficiency impairs the proliferation and survival of leukemia cells through regulating oncogenic signaling pathways. While PRLs are potential novel therapeutic targets in hematological malignancies, their exact biological function and cellular substrates remain unclear. This review will discuss how PRLs regulate hematopoietic stem cell behavior, what signaling pathways are regulated by PRLs, and how to target PRLs in hematological malignancies. An improved understanding of how PRLs function and how they are regulated may facilitate the development of PRL inhibitors that are effective in cancer treatment.  相似文献   

8.
BackgroundAs an essential micronutrient, zinc plays an important role in modulating the immune system. However, data on the association between zinc concentrations and asthma incidence are sparse, especially in adults.MethodsWe prospectively followed up 3682 individuals aged 20–32 years without history of asthma or current asthma at baseline from 1987–1988 to 2015–2016. Zinc concentrations were measured in toenail clippings collected at Exam Year 2 using inductively-coupled-plasma mass spectroscopy. Asthma was diagnosed by a physician and/or reported medication use for asthma control with verification. Cox regression was used to model the association between toenail zinc concentrations and asthma incidence.ResultsOver an average of 22.5 years of follow-up, 508 incident cases of asthma were identified. After adjustment for potential confounders, no statistically significant association was found between zinc concentration and asthma incidence (HR = 0.81; 95% CI: 0.62, 1.07; Plinear trend = 0.26). The observed association was not materially modified by sex, body mass index, smoking or atopic status. When stratifying data by race, a significant inverse linear association was found among African Americans (per 1 standard deviation increment in toenail zinc concentrations: HR = 0.86; 95% CI: 0.75, 0.99; Plinear trend = 0.03), but not in Caucasians (HR = 1.07; 95% CI: 0.91, 1.25; Plinear trend = 0.42), though the test for interaction was not statistically significant (Pinteraction = 0.099).ConclusionsFindings from this prospective cohort study do not support a significant longitudinal association between toenail zinc concentrations and incidence of asthma among American young adults. Future studies are needed to confirm our findings.  相似文献   

9.
The involvement of reactive oxygen species (ROS) and oxidative stress in pediatric diseases is an important concern, but oxidative stress status in healthy young subjects and appropriate methods for its measurement remain unclear. This study evaluated a comprehensive set of urinary biomarkers for oxidative stress in healthy children, adolescents and young adults. Results show that urinary excretion of acrolein–lysine, 8-hydroxy-2′-deoxyguanosine (8-OHdG), nitrite/nitrate and pentosidine were highest in the youngest subjects and decreased to constant levels by early adolescence. Urinary acrolein–lysine, 8-OHdG, nitrite/nitrate and pentosidine showed significant inverse correlations with age, but pyrraline did not change significantly with age. No significant differences in biomarkers were apparent between males and females. Younger subjects grow rapidly and sustain immune activation, and are probably exposed to high concentrations of ROS and nitric oxide. Consequently, they are more vulnerable to oxidation of lipids, proteins, DNA and carbohydrates. Normal reported values in this study are a basis for future studies of disease mechanisms involving oxidative stress and for future trials using antioxidant therapies for oxidative stress-related diseases in the pediatric field.  相似文献   

10.
The involvement of reactive oxygen species (ROS) and oxidative stress in pediatric diseases is an important concern, but oxidative stress status in healthy young subjects and appropriate methods for its measurement remain unclear. This study evaluated a comprehensive set of urinary biomarkers for oxidative stress in healthy children, adolescents and young adults. Results show that urinary excretion of acrolein-lysine, 8-hydroxy-2'-deoxyguanosine (8-OHdG), nitrite/nitrate and pentosidine were highest in the youngest subjects and decreased to constant levels by early adolescence. Urinary acrolein-lysine, 8-OHdG, nitrite/nitrate and pentosidine showed significant inverse correlations with age, but pyrraline did not change significantly with age. No significant differences in biomarkers were apparent between males and females. Younger subjects grow rapidly and sustain immune activation, and are probably exposed to high concentrations of ROS and nitric oxide. Consequently, they are more vulnerable to oxidation of lipids, proteins, DNA and carbohydrates. Normal reported values in this study are a basis for future studies of disease mechanisms involving oxidative stress and for future trials using antioxidant therapies for oxidative stress-related diseases in the pediatric field.  相似文献   

11.

Background

There is need for locally-derived age-specific clinical laboratory reference ranges of healthy Africans in sub-Saharan Africa. Reference values from North American and European populations are being used for African subjects despite previous studies showing significant differences. Our aim was to establish clinical laboratory reference values for African adolescents and young adults that can be used in clinical trials and for patient management.

Methods and Findings

A panel of 298, HIV-seronegative individuals aged 13–34 years was randomly selected from participants in two population-based cross-sectional surveys assessing HIV prevalence and other sexually transmitted infections in western Kenya. The adolescent (<18 years)-to-adults (≥18 years) ratio and the male-to-female ratio was 1∶1. Median and 95% reference ranges were calculated for immunohematological and biochemistry values. Compared with U.S-derived reference ranges, we detected lower hemoglobin (HB), hematocrit (HCT), red blood cells (RBC), mean corpuscular volume (MCV), neutrophil, glucose, and blood urea nitrogen values but elevated eosinophil and total bilirubin values. Significant gender variation was observed in hematological parameters in addition to T-bilirubin and creatinine indices in all age groups, AST in the younger and neutrophil, platelet and CD4 indices among the older age group. Age variation was also observed, mainly in hematological parameters among males. Applying U.S. NIH Division of AIDS (DAIDS) toxicity grading to our results, 40% of otherwise healthy study participants were classified as having an abnormal laboratory parameter (grade 1–4) which would exclude them from participating in clinical trials.

Conclusion

Hematological and biochemistry reference values from African population differ from those derived from a North American population, showing the need to develop region-specific reference values. Our data also show variations in hematological indices between adolescent and adult males which should be considered when developing reference ranges. This study provides the first locally-derived clinical laboratory reference ranges for adolescents and young adults in western Kenya.  相似文献   

12.
13.
Angiostrongylus cantonensis is an important causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. MicroRNAs (miRNAs) are small non-coding RNAs that participate in a wide range of biological processes. This study employed a deep-sequencing approach to study miRNAs from young adults of A. cantonensis. Based on 16,880,456 high-quality reads, 252 conserved mature miRNAs including 10 antisense miRNAs that belonging to 90 families, together with 10 antisense miRNAs were identified and characterised. Among these sequences, 53 miRNAs from 25 families displayed 50 or more reads. The conserved miRNA families were divided into four groups according to their phylogenetic distribution and a total of nine families without any members showing homology to other nematodes or adult worms were identified. Stem-loop real-time polymerase chain reaction analysis of aca-miR-1-1 and aca-miR-71-1 demonstrated that their level of expression increased dramatically from infective larvae to young adults and then decreased in adult worms, with the male worms exhibiting significantly higher levels of expression than female worms. These findings provide information related to the regulation of gene expression during the growth, development and pathogenesis of young adults of A. cantonensis.  相似文献   

14.
State and management of wetlands in Bangladesh   总被引:1,自引:0,他引:1  
Wetlands are a vital link between land and water in Bangladesh. A majority of the people of Bangladesh are critically dependent on wetlands. In this paper, the values of wetlands, causes and effects of wetlands degradation, as well as the present wetlands management approach, are analyzed and recommendations for wetlands management are suggested based on participatory rural appraisal (PRA), field visit, personal experience, and existing literature and information. Wetlands play a crucial role in maintaining the ecological balance of ecosystems, but wetlands habitat of Bangladesh is under constant threat due to increase of population, intensive agriculture, overfishing, siltation, pollution, ill-planned infrastructures, lack of institutional coordination, lack of awareness, etc. As a result biodiversity is reducing, many species of flora and fauna are threatened, wetlands-based ecosystem is degenerating, and the living conditions of local people are deteriorating as livelihoods, socioeconomic institutions, and cultural values are affected. Wetlands management is not addressed separately in water management activities of Bangladesh. In order to balance human needs and wetlands conservation, a mainly community-based wetlands management approach has been taken in Bangladesh, but this is not enough to prevent the degradation of wetlands. Therefore, Bangladesh now needs a comprehensive strategy combining political, economic, social, and technological approaches to stop further degradation of wetlands. Therefore, wetlands management should be incorporated into a system of integrated land and water use and, indeed, into the socioeconomic system of the country. Policies, strategies, and management plans for sustainable use and conservation of wetlands of Bangladesh must be based on solid knowledge and understanding of their ecological and socioeconomic functions and processes.  相似文献   

15.
Citrinin (CIT) and Ochratoxin A (OTA) are nephrotoxic mycotoxins which can co-occur in food commodities, resulting in internal exposure. Studies in many countries reported on the presence of OTA in human blood; however, such biomonitoring data for CIT is still scarce. This study was conducted to characterize both CIT and OTA biomarker levels in plasma of volunteers since food analysis data are insufficient to assess human exposure in Bangladesh. In total 104 blood samples were collected from university students in 2013 (sampling 1: n?=?64, midsummer) and 2014 (sampling 2: n?=?40, end winter) for analysis of CIT and OTA and their metabolites HO-CIT and OTα by LC-MS/MS and HPLC-FD techniques, respectively. CIT and HO-CIT were detected in 90% (max 2.70 ng/mL) and 85% (max 1.44 ng/mL) of all samples. Mean levels in sampling 2 (CIT 0.47 ng/mL; HO-CIT 0.40 ng/mL) were higher than in sampling 1 (0.25 ng/mL; 0.37 ng/mL) indicative of variable CIT exposure. OTA was present in all (max 6.63 ng/mL) and OTα in 98% (max 0.99 ng/mL) of the samples. In sampling 1, mean OTA (0.85 ng/mL) was higher than in sampling 2 (0.51 ng/mL); the reverse situation was found for OTα mean levels. The calculated dietary OTA intake among the students (mean 9.9; max 91.7 ng/kg bw/week) was lower than the tolerable weekly intake for this mycotoxin (120 ng/kg bw/week) set by EFSA. But frequent co-exposure to CIT should be considered, and the results of this study indicate the necessity to identify major sources of CIT and OTA intake in the Bangladeshi population.  相似文献   

16.
Ma J  Ma D  Ji C 《Cytokine》2011,56(2):133-139
IL-21, the newest member of the common γ-chain family of cytokines, has pleiotropic biological effects through regulating a variety of immune cells. Recently, the role of IL-21 in the treatment of cancers has been widely investigated. Conducted phase I trials in metastatic malignant melanoma and renal cell carcinoma have shown that rIL-21 has a favorable antitumor activity. Expression of IL-21 and IL-21R has also been found in many types of hematological malignancies, such as chronic lymphocytic leukemia (CLL), multiple myeloma (MM) and lymphoma. Through binding with IL-21R, IL-21 induces activation of different JAK/STAT signal transduction pathways and regulates proliferation or apoptosis of tumor cells. In this review, we will discuss the expression of IL-21/IL-21R and its effect in different types of hematological malignancies.  相似文献   

17.
Clarias gariepinus, weighing 119.18 ± 5.21 g, were exposed to 0%, 20%, 40%, and 60% of the LC50 lead nitrate, Pb(NO3)2, which represents the following treatments 0 (control), 16, 32, and 48 mg/l, respectively, for a period of 10 and 20 days. The results showed that the bioaccumulation of Pb(NO3)2 in gills were significantly increased (p < 0.05) after 10 days having 0.17 ± 0.07, 5.05 ± 1.04, 6.01 ± 0.82, and 9.61 ± 1.76 mg/100 g wet weight, respectively, for the treatments. However, after 20 days these values increased ((0.17 ± 0.07, 4.34 ± 1.27, 10.83 ± 0.97, and 19.18 ± 2.40 mg/100 g) for 0%, 20%, 40%, and 60% of LC50 Pb(NO3)2 respectively. There was an increase with each increasing concentration level of Pb(NO3)2 as compared with that of the control group. The accumulation of Pb(NO3)2 in the liver, showed a significant increase (p < 0.05) with the increasing period of exposed and Pb concentration with LC50 values ranging between 3.32 ± 0.91 and 4.42 ± 0.78 after 10 days as compared with that of the control group 0.08 ± 0.02 mg/100 g wet weight. Although white muscles and skin displayed lower values of bioaccumulation than gills and liver after 10 days, after 20 days the results were slightly more increased in the white muscles than in the skin. However, the observed pattern of increase was the same compared to that of the control group. Therefore, hematological parameters, such as red blood cells (RBCs), hemoglobin (Hb), and hematocrit (Hct) showed significant (p < 0.05) concentration-dependent decreases in fish exposed to Pb(NO3)2 during both periods. However, the values of white blood cells (WBCs) showed a significant reduction when levels of Pb concentration increased. Hepatic enzyme activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) displayed a significant increase with increasing concentrations and exposure time.  相似文献   

18.
BackgroundThe incidence of colorectal cancer (CRC) in young adults is increasing. Minority populations with CRC are known to have worse survival outcomes. The aim of this study is to evaluate adults under age 50 years with CRC by race and ethnicity.MethodsData were obtained from all US hospitals that contributed to the National Cancer Database (NCDB) between 2004 and 2013. Univariate and multivariable testing was done to identify factors associated with patient outcome. Kaplan-Meier analysis and Cox proportional hazards models were used for association between patient characteristics and survival.ResultsA total of 83,449 patients between 18 and 50 years of age were identified. Median age was 45 years (SD ± 6), with male preponderance (53.9%). 72% were non-Hispanic Whites (NHW), Blacks (AA) were 15.1% and Hispanics (who did not identify as Blacks) were 8.3% of the study population. Distribution across stages IIV was 15.6%, 22.4%, 33.9% and 27% consecutively. 41.8% of NHW and 28.4% of AA had rectal cancers (p < 0.001). Despite equally receiving standard of care (SOC) as per national guidelines, AA had significantly lower 5-year survival rates (58.8%) compared to Hispanics (64.8%) and NHW (66.9%; HR 1.42; 1.38-1.46; p < 0.001). Furthermore, NHW (HR 0.85; 0.81-0.88; p < 0.001) and Hispanics (HR 0.75; 0.70-0.79; p < 0.001) were more likely to benefit from chemotherapy compared to AA. SOC utilization was associated with improved survival across all racial groups, especially in AA (HR 0.64; 0.60-0.69; p < 0.001).ConclusionDespite comparable rates of SOC utilization, AA young adults had worse survival outcomes compared to other races. More colon (compared to rectal) cancers in AA may have contributed to their worse outcomes.  相似文献   

19.
The aim of the present study was to obtain a basic knowledge of the hematology of Cichlasoma dimerus. The morphological features of blood cells were described according to the observations made by light and electron microscopy. Erythrocytes, thrombocytes and four types of leucocytes: lymphocytes, monocytes, heterophils and eosinophils, were distinguished and characterized. Thrombocytes are the most abundant blood cells after erythrocytes and are recognized easily from lymphocytes by morphological features and size. Heterophils and eosinophils are PAS positive. Hematological indices (RBC, WBC, PCV, Hb, MCV, MCH, MCHC and leucocyte differential count) were measured in one blood sample from 30 adult fish captured in Esteros del Riachuelo, Corrientes, Argentina (27 degrees 25'S, 58 degrees 15'W). The reference interval and the mean were determined for each hematological parameter evaluated. Contrary to other species, the percent of heterophils was found to be high in relation to the percent of lymphocytes. Low lymphocyte counts occurred in C. dimerus, as compared to these found in other fishes. Compared to most teleosts, this species has similar mean values for PCV and Hb and slightly higher for RBC. Statistical analysis revealed that differences in hematological parameters between male and female fish were not significant.  相似文献   

20.
Objective: To assess the association of weight change based on serial self‐reported vs. measured weights. Research Methods and Procedures: Two thousand two hundred eighty‐four male and 2476 female participants in the National Longitudinal Study of Adolescent Health who provided information on weight at Waves II and III and were at least 16 years of age were studied. Linear regression was used to assess predictors of the discrepancy between weight change based on self‐reported vs. measured weights. Logistic regression was used to identify predictors of self‐report correctly classifying participants in terms of weight change category. Results: Self‐reported weight was slightly lower than measured weight at Waves II and III, but weight change based on self‐reported weights underestimated true weight change by only 2.1 (female participants) to 2.8 (male participants) pounds. Overweight and obese female participants were consistent in their under‐reporting of their weight more than their leaner peers; thus, the discrepancy between weight change from Wave II to Wave III based on serial self‐reports vs. measured weights was significantly smaller among the obese female vs. healthy‐weight female participants (0.3‐ vs. 2.3‐pound underestimation, p < 0.05). Among the male participants, the same pattern was evident. African‐American ethnicity, Hispanic ethnicity, the level of physical activity, the hours per week watching television, and weight change efforts were not related to the discrepancy between weight change based on self‐reported vs. measured weights. Discussion: The discrepancy between weight change based on self‐report vs. measured weights was minor and not related to race, weight change efforts, activity, or inactivity, thus suggesting that much of the error is random.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号