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541.
Acute and chronic viral hepatitis infections are corresponding to increase the risk of different types of hematological malignancies
especially with leukemia. In this study the serological and molecular markers of hepatitis viruses were evaluated in patients
with different types of leukemia in comparing with control group. In this cross sectional study, 100 EDTA-treated blood samples
were collected from leukemia patients and also from healthy control group, respectively. Serological and molecular markers
of HBV, HCV and HDV viruses were analyzed for determination of the role of these hepatitis viruses in clinical outcomes of
leukemia disorders. Increasing risk factors of leukemia were evaluated statistically in two studied groups by SPSS software.
One of molecular and immunological markers of HBV, HDV and HCV was found in 24 of 100 (24%), 22 of 100 (22%), and 1 of 100
(1%) patients with leukemia and in 12 of 100 (12%), 6 of 100 (6%), and 2 of 100 (2%) control patients. Significant differences
were detected in detection of HBsAg (P = 0.02), HBeAb (P = 0.009), and HCV-RNA (P = 0.05) between leukemia patients and control group, respectively. The high prevalence of HBV and HCV infective markers were
detected in ALL and AML patients. Identification of high prevalence of HBV and HCV infective markers in leukemia patients
proposed strong association between hepatitis viral infections and leukemia. Therefore, evaluation of the prevalence of viral
hepatitis infections in larger groups of patients with long lasting follow up is suggesting. 相似文献
542.
Hussain SR Babu SG Raza ST Singh P Ahmed F Naqvi H Mahdi F 《Molecular biology reports》2012,39(9):9139-9144
Breast cancer is one of the most frequently diagnosed cancers and the leading cause of cancer deaths among females across the world, accounting for 23 % (1.38 million) of total new cancer cases and 14 % (0.45 million) of the total cancer deaths in 2008. c-kit is expressed in mast cell growth factor, cellular migration, proliferation, melanoblasts, haematopoietic progenitors and germ cells. We have designed our study with aim to explore the c-kit gene mutations in invasive ductal carcinoma (IDC) breast. To ascertain the range of mutations in exon 11, 13 and 17 of c-kit gene in 53 cases of IDC breast, we carried out PCR-SSCP followed by DNA sequencing. The mutation frequency of c-kit gene in exon 11, 13 and 17 were 9.43 % (5/53), 1.88 % (1/53) and 3.77 % (2/53), respectively. During our mutational analysis, we have detected five missense mutations in exon 11 (Pro551Leu, Glu562Val, Leu576Phe, His580Tyr and Phe584Leu), one missense mutation in exon 13 (Ser639Pro) and two missense mutations in exon 17 (Arg796Gly and Asn822Ser). It seems that c-kit mutations might participate in breast cancer pathogenesis and may be utilized as predictive marker, since the loss of c-kit positivity is generally linked with different types of breast cancer. Further molecular studies are necessary to validate the association of c-kit gene mutation in IDC breast pathogenesis. 相似文献
543.
Mohammadnejad Z Ghanbari M Ganjali R Afshari JT Heydarpour M Taghavi SM Fatemi S Rafatpanah H 《Molecular biology reports》2012,39(2):831-837
Type 1 diabetes mellitus (T1DM) is one of the T-cell mediated autoimmune diseases and vitamin D suppresses activation of T-cell
and has immunomodulatory effects. In this study the association between four vitamin D receptor (VDR) gene polymorphisms,
at positions FokI, BsmI, ApaI and TaqI, and susceptibility to T1DM was investigated. We assessed 87 Iranian patients with
T1DM and one hundred healthy controls with no history of diabetes or other autoimmune diseases. Our results demonstrated that
genotypes frequency of the TaqI VDR polymorphism differed significantly between T1DM patients and controls, TT genotype and
T allele was more frequent in healthy controls compared with TIDM patients (P = 0.003; OR = 0.51, 95% CI = 0.31–0.84). Therefore, allele t is the risk-allele for developing TIDM in this study. No significant association was observed
between others VDR SNPs and disease susceptibility. In conclusion, our case-control study indicated that the VDR TaqI polymorphism
is associated with TIDM in Iranian population. 相似文献
544.
Gupta A Dwivedi M Mahdi AA Khetrapal CL Bhandari M 《Journal of proteome research》2012,11(3):1844-1854
To address the shortcomings of urine culture for the rapid identification of urinary tract infection (UTI), we applied (1)H-nuclear magnetic resonance (NMR) spectroscopy as a surrogate method for fast screening of microorganisms. Study includes 682 urine samples from suspected UTI patients, 50 healthy volunteers, and commercially available standard strains of gram negative bacilli (GNB) (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterobacter, Acinetobacter, Proteus mirabilis, Citrobacter frundii) and gram positive cocci (GPC) (Enterococcus faecalis, Streptococcus group B, Staphylococcus saprophyticus). Acetate, lactate, ethanol, succinate, creatinine, trimethylamine (TMA), citrate, trimethylamin-N-oxide, glycine, urea, and hippurate were measured by (1)H NMR spectroscopy. All urine specimens were evaluated with culture method. Multivariate discriminant function analysis (DFA) reveals that acetate, lactate, succinate, and formate were able to differentiate, with high accuracy (99.5%), healthy controls from UTI patients. This statistical analysis was also able to classify GNB to GPC infected urine samples with high accuracy (96%). This technique appears to be a promising, rapid, and noninvasive approach to probing GNB and GPC infected urine specimens with its distinguishing metabolic profile. The determination of infection will be very important for rapidly and efficiently measuring the efficacy of a tailored treatment, leading to prompt and appropriate care of UTI patients. 相似文献
545.
AR Jassbi M Asadollahi M Masroor MC Schuman Z Mehdizadeh M Soleimani R Miri 《Chemistry & biodiversity》2012,9(7):1254-1271
The essential oils of eight Salvia species collected from different localities in Iran were analyzed by gas chromatography/mass spectrometry (GC/MS). The analytical results were compared with those previously published for related Iranian sage species in order to identify chemical markers for these species. Salvia eremophila, S. hypoleuca, and S. reuteriana are endemic, while S. atropatana, S. chloroleuca, S. santolinifolia, S. aegyptiaca, and S. macrosiphon also grow wild in neighboring countries. We categorized the Iranian Salvia species into four main chemotypes according to their essential-oil constituents: those which are dominated by 1) monoterpenes, 2) mono- and sesquiterpenes, or 3) sesquiterpenes as the major constituents, and 4) those containing low-molecular-weight acids, aldehydes, and esters, and green-leaf volatiles (GLVs). Likely due to the chemical diversity of different Salvia chemotypes, this categorization was supported by principal component analysis (PCA) for the group sampled here, but not for the values reported in the literature. We identified the following chemical markers: α-pinene, β-pinene, 1,8-cineol, linalool, and borneol in monoterpene-rich species, or β-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, and caryophyllene oxide in sesquiterpene-rich species. Among these, α-pinene, β-caryophyllene, and germacrene D are the most common and abundant in the Salvia species investigated. In accordance with their close biological taxonomy, the chemical similarity of the essential oils of S. santolinifolia and S. eremophila is so high that we may consider them chemically identical. 相似文献
546.
Ahmed Hosny Sherif M. El-Hady A. Mohamed Abou El-Ela Giuliano F. Panza Ali Tealeb Mahdi Adb El Rahman 《Rendiconti Lincei》2009,20(1):1-19
3-Dimages of P-wave velocity and Vp/Vs ratio have been produced for the upper crust of the Abu Dabbab area, North Mars Alam
city. The inversion of local travel times of high quality data recorded at eleven mobile seimic stations around the study
area is carried out. The best, in the least-squares sense, 1-D Vp model and the average value of Vp/Vs (1.72) were computed
as prerequisites of the 3-D inversion that reaches a depth of 14 km. From the 3-D model it is evident that the distributions
of Vp and Vp/Vs are characterized by marked lateral and vertical variations delineating structural heterogeneities. Due to
the presence of a thin layer of sedimentary rocks saturated with surface water, low P-wave velocity and high Vp/Vs values
are noticed near the surface. At greater depths, high Vp and low Vp/Vs zones may indicate crustal rocks with relatively higher
rigidity and brittle behavior, while high Vp/Vs and low Vp may identify zones of relatively softer rocks, with ductile behavior.
Low P-wave velocity values are observed at the intersections among the faults. A possibility of some magma intrusion could
be associated with the high Vp/Vs values which form an elongated anomaly, in the central part of the study area, which extends
from a depth of 12 km to about 1–2 km of depth.
If the obtained 3-D model is used in the relocation of selected events, they turn out to be strongly clustered in correspondence
with the high velocity anomalies detected in the central part of the study area. Most of the seismicity tends to occur at
the boundaries between the high and low velocity anomalies and at pre-existing weakness zones, i.e. the areas of intersection
among different faults. The occurrence of the seismic activity in the vicinity of low velocity anomalies and at the boundary
between velocity contrast could also be explained by the occurrence of serpentinization processes in the crust of the study
area.
相似文献
547.
Hassani K Navidbakhsh M Rostami M 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2006,150(1):105-112
This paper describes simulation of the cardiovascular system using a complex electronic circuit. In this study we have taken a slightly different approach to the modeling of the system and tried to advance existing electrical models by increasing more segments and parameters. The model consists of 42 segments representing the arterial system. Anatomical and physiological data for circuit parameters have been extracted from medical articles and textbooks. The frequency of heart is 1 Hz and the system operates in steady state condition. Each artery is modeled by one capacitor, resistor and inductor. The left and right ventricles are modeled using AC power suppliers and diodes. The results of the simulation including pressure and volume graphs exhibit operation of the cardiovascular system under normal condition. The results of the simulation have been compared with the relevant experimental observation and are in good agreement with them. 相似文献
548.
549.
J. G. Mahdi C. J. Pepper† M. A. Alkarrawi‡ A. J. Mahdi§ I. D. Bowen‡ 《Cell proliferation》2010,43(1):95-102
Objectives: To examine the effect of a novel phenolic-based compound, 2-hydroxy benzoate zinc (2HBZ), and acetylsalicylic acid (ASA) on human HT-1080 fibrosarcoma cells.
Materials and methods: MTT assay was used to assess cell proliferation while different methods were used to detect apoptosis morphologically and immunohistochemically in Human HT-1080 fibrosarcoma cells. Apoptosis was determined by Annexine-V labelling, and caspase-3 activation. In addition, western blot was used to analyse p21, p53 and Bax and flow cytometry was to analyse the cell cycle.
Results: 2HBZ exhibited a more than 5-fold increase in cytotoxic potency when compared with ASA with mean LD50 values of 210 and 1100 lM respectively ( P < 0.0001). The cytotoxic effects of 2HBZ were both time- and dosedependent with marked apoptosis being evident only after 24 h at concentrations as low as 200 mM. In contrast, ASA-induced apoptosis was observed only at concentrations in excess of 1000 mM at the same time point. Both 2HBZ and ASA induced caspase-3 activation in the cells, which confirmed that their cytotoxic effects were the result of apoptotic cell death. These findings were further confirmed by immunomorphological studies for the detection of apoptosis including haematoxylineosin, methyl green/pyronin Y staining and scanning electron microscopy. In addition, 2HBZ caused a marked increase in p21, p53 and Bax protein expressions and these effects were associated with an increase in G1 and G2 arrest of the cell cycle and a reduction in S-phase.
Conclusions: These results demonstrate that the novel phenolic compound 2HBZ is a potent apoptosis-inducing agent in HT-1080 cells and warrants further investigation as a potential chemotherapeutic agent in primary cancer cell models. 相似文献
Materials and methods: MTT assay was used to assess cell proliferation while different methods were used to detect apoptosis morphologically and immunohistochemically in Human HT-1080 fibrosarcoma cells. Apoptosis was determined by Annexine-V labelling, and caspase-3 activation. In addition, western blot was used to analyse p21, p53 and Bax and flow cytometry was to analyse the cell cycle.
Results: 2HBZ exhibited a more than 5-fold increase in cytotoxic potency when compared with ASA with mean LD50 values of 210 and 1100 lM respectively ( P < 0.0001). The cytotoxic effects of 2HBZ were both time- and dosedependent with marked apoptosis being evident only after 24 h at concentrations as low as 200 mM. In contrast, ASA-induced apoptosis was observed only at concentrations in excess of 1000 mM at the same time point. Both 2HBZ and ASA induced caspase-3 activation in the cells, which confirmed that their cytotoxic effects were the result of apoptotic cell death. These findings were further confirmed by immunomorphological studies for the detection of apoptosis including haematoxylineosin, methyl green/pyronin Y staining and scanning electron microscopy. In addition, 2HBZ caused a marked increase in p21, p53 and Bax protein expressions and these effects were associated with an increase in G1 and G2 arrest of the cell cycle and a reduction in S-phase.
Conclusions: These results demonstrate that the novel phenolic compound 2HBZ is a potent apoptosis-inducing agent in HT-1080 cells and warrants further investigation as a potential chemotherapeutic agent in primary cancer cell models. 相似文献
550.
Nasser Masroori Raheleh Halabian Mahshid Mohammadipour Amaneh Mohammadi Roushandeh Mahdi Rouhbakhsh Ali Jahanian Najafabadi Mahdi Edalati Fathabad Mohamad Salimi Mohamad Ali Shokrgozar Mehryar Habibi Roudkenar 《Biotechnology letters》2010,32(6):803-809
Recombinant coagulation factor VII (FVII) is used as a potential therapeutic intervention in hemophilia patients who produce
antibodies against the coagulation factors. Mammalian cell lines provide low levels of expression, however, the Spodoptera frugiperda Sf9 cell line and baculovirus expression system are powerful systems for high-level expression of recombinant proteins, but
due to the lack of endogenous vitamin K-dependent carboxylase, expression of functional FVII using this system is impossible.
In the present study, we report a simple but versatile method to overcome the defect for high-level expression of the functional
recombinant coagulation FVII in Sf9 cells. This method involves simultaneous expression of both human γ-carboxylase (hGC)
and human FVII genes in the host. It may be possible to express other vitamin K-dependent coagulation factors using this method
in the future. 相似文献