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141.
Claire J. Schwab Lucy Chilton Heather Morrison Lisa Jones Halima Al-Shehhi Amy Erhorn Lisa J. Russell Anthony V. Moorman Christine J. Harrison 《Haematologica》2013,98(7):1081-1088
In childhood B-cell precursor acute lymphoblastic leukemia, cytogenetics is important in diagnosis and as an indicator of response to therapy, thus playing a key role in risk stratification of patients for treatment. Little is known of the relationship between different cytogenetic subtypes in B-cell precursor acute lymphoblastic leukemia and the recently reported copy number abnormalities affecting significant leukemia associated genes. In a consecutive series of 1427 childhood B-cell precursor acute lymphoblastic leukemia patients, we have determined the incidence and type of copy number abnormalities using multiplex ligation-dependent probe amplification. We have shown strong links between certain deletions and cytogenetic subtypes, including the novel association between RB1 deletions and intrachromosomal amplification of chromosome 21. In this study, we characterized the different copy number abnormalities and show heterogeneity of PAX5 and IKZF1 deletions and the recurrent nature of RB1 deletions. Whole gene losses are often indicative of larger deletions, visible by conventional cytogenetics. An increased number of copy number abnormalities is associated with NCI high risk, specifically deletions of IKZF1 and CDKN2A/B, which occur more frequently among these patients. IKZF1 deletions and rearrangements of CRLF2 among patients with undefined karyotypes may point to the poor risk BCR-ABL1-like group. In conclusion, this study has demonstrated in a large representative cohort of children with B-cell precursor acute lymphoblastic leukemia that the pattern of copy number abnormalities is highly variable according to the primary genetic abnormality. 相似文献
142.
Rashid F Ahmed R Mahmood A Ahmad Z Bibi N Kazmi SU 《Archives of pharmacal research》2007,30(8):932-937
Investigations on the chemical constituents of the fruits of Prunus armeniaca have led to the isolation of two new flavonoid glycosides, 4',5,7-trihydroxy flavone-7-O-[beta-D-mannopyranosyl (1'-->2")]-beta-D-allopyranoside (1) and 3,4',5,7-tetrahydroxy-3',5'-di-methoxy flavone 3-O-[alpha-L-rhamnopyranosyl (1'-->6")]-beta-D-galactopyranoside (2), from the butanolic fraction of the fruits. The butanolic extract exhibited antibacterial activity against both Gram positive and Gram negative bacteria. The structures of these compounds were elucidated through spectral studies, including 2D-NMR (COSY, NOESY, J-resolved), HMQC and HMBC experiments. 相似文献
143.
Cytokine profiles and antibody responses to Plasmodium falciparum malaria infection in individuals living in Ibadan, southwest Nigeria 下载免费PDF全文
Nnaemeka C Iriemenam Christian M F Okafor Halima A Balogun Idowu Ayede Yusuf Omosun Jan-Olov Persson Margareta Hagstedt Chiaka I Anumudu Roseangela I Nwuba Marita Troye-Blomberg Klavs Berzins 《African health sciences》2009,9(2):66-74
Background
The ability of the host immune system to efficiently clear Plasmodium falciparum parasites during a malaria infection depends on the type of immune response mounted by the host.Study design
In a cross-sectional study, we investigated the cellular-and antibody responses in individuals with P. falciparum infection, in an attempt to identify immunological signs indicative of the development of natural immunity against malaria in Ibadan, Nigeria. Levels of IL-10, IL-12(p70), IFN-γ, and IgM, IgG and IgG1-4 subclasses in the serum of 36 symptomatic children with microscopically confirmed malaria parasitaemia and 54 asymptomatic controls were analysed by ELISA.Results
IFN-γ and IL-10 were significantly higher in the symptomatic children (p=0.009, p=0.025 respectively) than in the asymptomatic controls but no differences were seen for IL-12(p70). Estimated higher ratios of IFN-γ/IL-10 and IFN-γ/IL-12 were also observed in the symptomatic children while the asymptomatic controls had higher IL-12/IL-10 ratio. The mean concentration levels of anti-P. falciparum IgG1, IgG2, IgG3 antibodies were statistically significantly higher in the individuals >5 years of age than <5 years while anti-P. falciparum IgG3 antibodies were notably low in <5 years category. Children <5 years had higher IgM antibodies than IgG and the expression of IgG subclasses increased with age.Conclusion
Taken together, malaria infection is on a delicate balance of pro- and anti-inflammatory cytokines. The higher levels of IFN-γ seen in the symptomatic children (<6 months) may be instrumental in immune-protection against malaria by limiting parasite replication. The observed variations in immunoglobulin subclass levels were age-dependent and exposure-related. 相似文献144.
Ouadid-Ahidouch H Dhennin-Duthille I Gautier M Sevestre H Ahidouch A 《Bulletin du cancer》2012,99(6):655-664
Breast cancer (BC) has the highest incidence rate in women in industrialized countries. Statistically, it is estimated that one out of 10 women will develop BC during her life. Evidence is accumulating for the role of ion channels in the development of cancer. Most studied ion channels in BC are K(+) channels, which are involved in cell proliferation, cell cycle progression and cell migration, and Na(+) channels, which correlate with invasiveness. Emerging studies demonstrated the role of Ca(2+) signaling in cancer cell proliferation, survival and migration. Recent findings demonstrated that the expression and/or activity of the transient receptor potential (TRP) channels are altered in several cancers. Among the TRP families, TRPC (canonical or classical), TRPM (melastatin) and TRPV (vanilloid) are related to malignant growth and cancer progression. Although these channels are frequently and abundantly expressed in many tumors, their specific expression, activity and roles in BC are still poorly understood. The expression of TRP channels has also been proposed as a tool for diagnosis, prognosis and/or therapeutic issues of several diseases. In cancer, TRPV6 and TRPM8 have been proposed as tumor progression markers of prostate cancer outcome and TRPC6 as a novel therapeutic target for esophageal carcinoma. Interestingly high levels of TRPC3 expression correlate with a favorable prognosis in patients with lung adenocarcinoma. Our team has recently reported the expression and role of TRPC1, TRPC6, TRPM7, TRPM8 and TRPV6 in BC cell lines and primary cultures. We have also investigated TRP expression and their clinical significance in human breast adenocarcinoma and we suggest that TRP channels are new potential BC markers. Indeed TRPC1 and TRPM8 may be considered as good prognosis markers of well-differentiated tumors, TRPM7 as a proliferative marker of poorly differentiated tumors and TRPV6 as a prognosis marker of aggressive cancers. In this review, we summarize the data reported to date regarding the changes in TRP expression associated with BC. We also discuss the importance of TRP channels in BC cells proliferation and migration and their interest as new BC markers. 相似文献
145.
Ethnopharmacological relevance
Four species of Podocarpus are used in traditional medicine both in human and animal healthcare in South Africa. In vitro pharmacological screening of leaf and stem extracts of these species exhibited potent antimicrobial, anti-inflammatory, anti-tyrosinase, anthelmintic, acetylcholinesterase inhibitory and antioxidant activities.Aim of the study
To investigate the mutagenicity, antimutagenicity and cytotoxicity effects of leaf and stem extract of South African Podocarpus species.Material and methods
The mutagenicity and cytotoxic effects of extracts from four species of Podocarpus were tested using the Salmonella/microsome assay with and without metabolic activation, based on the plate-incorporation method and neutral red uptake (NRU) assay respectively. Five Salmonella typhimurium tester strains; TA98, TA100, TA102, TA1535 and TA1537 were used for mutagenicity testing. The relative cytotoxicity of the extracts was assessed by determining their NI50 values (50% inhibition of NRU).Results
The extracts did not show any mutagenic effects against all the tester strains with or without metabolic activation. All extracts demonstrated a strong antimutagenic effect on the mutations induced by 4NQO, decreasing its mutagenic effect in a dose-dependent manner. Strong cytotoxic effects were exhibited by petroleum ether extracts as compared to 80% ethanol extracts. When HepG2 cells were in contact with plant extracts in an increasing concentration, slopes of NRU decreased (highest-lowest %) following a concentration-dependent pattern. For 80% ethanol extracts, the most toxic extract in terms of percentage viability was leaves of Podocarpus falcatus whereby at 0.2 mg/ml, the viability of the cells was 38.9%. Stem extract of Podocarpus latifolius was the most toxic among PE extracts, giving a percentage viability of 46.4 at 0.1 mg/ml.Conclusion
Absence of mutagenicity does not indicate lack of toxicity, as was observed from these extracts. These findings will help in assessing the safety measures to be considered in the use of these species and also the need to determine the cytotoxic potential of these species against various forms of human cancer cells. 相似文献146.
Our objective was to identify factors that correlate with high CA125 (cancer antigen 125) concentrations in Tunisian women with epithelial ovarian cancer and to introduce recommendations for reporting and interpreting individual CA125 assay results. We analyzed repeated serum CA125 levels, by the immunoenzymatic assay using an AxSym CA125 kit, in 90 patients who were treated for ovarian cancer from 1994 to 2006 in CHU Farhat Hached Sousse Tunisia. Using a logistic model, we found that carcinosis is significantly predictive of high levels of serum CA125 (p = 0.005). A woman's age (> or = 45 years, p = 0.016) and menopausal status (postmenopausal patient, p = 0.034) are also predictive of increased CA125 concentration. Patients with serous histological subtype have higher CA125 values (p = 0.001). Presence of ascites is associated with high serum CA125 values and thus could be considered as a predictor of high serum CA125 concentration (p = 0.023). The International Federation of Gynecology and Obstetrics stage and primary tumor size are not significant predictors of CA125 concentrations (p > 0.05). We conclude that clinically significant parameters should lead to the best interpretation of rising CA125 levels and consequently to more appropriate management of epithelial ovarian cancer patients. 相似文献
147.
Barbier C Legeais M Cottier JP Bibi R Herbreteau D 《Journal of neuroradiology. Journal de neuroradiologie》2008,35(4):230-235
This is a case report of successful arterial embolization of a dural fistula using absolute alcohol. In this two-part embolization of a dural fistula of the left sagittal venous sinus, the use of n-BCA (n-butyl-cyanoacrylate) was followed by 1 ml of absolute alcohol four months later. The first procedure, using n-BCA via the external carotid, permitted exclusion of the arterial supply coming from the medial meningeal and occipital arteries. Persistence of the blood supply through the internal carotid prompted us to perform the second procedure, to occlude the tentorium marginalis artery, using 1 ml of 95% ethanol. This was followed by a cranial nerve (III) palsy that was reversible. The three-month follow-up was satisfactory, although arteriography after one year showed revascularization of the fistula, which was successfully treated by Onyx. Routinely used in the treatment of superficial vascular malformations, the use of absolute alcohol intracerebrally appears to be unreliable, with results that were only temporary. 相似文献
148.
Alamiri B 《The American journal of psychiatry》2008,165(9):1205-6; author reply 1207
149.
Ben Halima A Ibn Elhadj Z Essmat W Léfi A Kammoun I Zouaoui W Marrakchi S Chine S Gargouri S Keskes H Kachboura S 《Journal des maladies vasculaires》2006,31(2):93-97
The incidence of tertiary syphilis has declined in recent years owing to the early recognition of the disease and use of antibiotics. As a result, syphilitic aortic aneurysms are rarely encountered nowadays. We report the case of a 65 years old man, who was admitted to our hospital in June 2004 for dyspnea, cough and chest discomfort. On physical examination, blood pressure was 130/80 mmHg with no significant laterality, pulse rate was 70 per minute and there was a decrease of breath sounds over the right lung. Laboratory findings revealed a slight elevation of the erythrocyte sedimentation rate. Serological studies for syphilis showed a positive venereal disease laboratory test (VDRL) at 1/32 and a positive Treponema pallidum hemagglutination test (TPHA) at 1/2560. The chest radiography showed a right para cardiac opacity measuring 16 x 12 cm. Fiber optic bronchoscopy showed an extrinsic compression of the right upper lobar bronchus. Gadolinium-enhanced magnetic resonance angiography and 16 multidetector-row spiral computed aortography showed a huge partially thrombosed saccular aneurysm of the ascending aorta measuring 132 mm in diameter. The circulating lumen measured 53 mm in its largest diameter. This aneurysm involved the innominate artery. There was no other arterial involvement. The patient was given a three week course of intravenous penicillin followed by a successful surgical procedure in September 2004 with ascending aortic replacement and innominate artery reimplantation. This case illustrates well a formerly common, but now extremely rare disease. 相似文献
150.