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31.
Background
Multiple Endocrine Neoplasia type 1 (MEN1, OMIM 131100) is an autosomal dominant disorder characterized by endocrine tumors of the parathyroids, pancreatic islets and pituitary. The disease is caused by the functional loss of the tumor suppressor protein menin, coded by the MEN1 gene. The protein sequence has no significant homology to known consensus motifs. In vitro studies have shown menin binding to JunD, Pem, Smad3, NF-kappaB, nm23H1, and RPA2 proteins. However, none of these binding studies have led to a convincing theory of how loss-of-menin leads to neoplasia. 相似文献32.
Ultrasound guided cytological aspiration of supraclavicular lymph nodes in patients with suspected lung cancer 总被引:2,自引:0,他引:2 下载免费PDF全文
Kumaran M Benamore RE Vaidhyanath R Muller S Richards CJ Peake MD Entwisle JJ 《Thorax》2005,60(3):229-233
BACKGROUND: Lung cancer is the leading cause of death from cancer in the UK. Pathological diagnosis traditionally requires invasive procedures such as bronchoscopy, mediastinoscopy, or image guided biopsy. Ultrasound of the neck with fine needle aspiration cytology (FNAC) of enlarged but impalpable supraclavicular nodes has been used in patients with suspected lung cancer who have N2 or N3 disease on staging computed tomography (CT). If positive, this technique helps to both stage the patient and provide a cytological diagnosis. METHODS: 101 patients were enrolled prospectively over a 1 year period. FNAC was performed on all supraclavicular nodes over 5 mm in size using the capillary aspiration technique. RESULTS: Sixty one of the 101 patients had enlarged supraclavicular nodes and underwent FNAC. The overall malignant yield was 45.5% of patients scanned and 75.4% of patients sampled. As a result of FNAC, 43 patients (42.6%) avoided more invasive procedures. CONCLUSION: Ultrasound guided FNAC is a promising, relatively non-invasive technique for the staging and diagnosis of patients with lung cancer. 相似文献
33.
Erythromycin taurate, a new derivative of erythromycin, was prepared by reacting erythromycin base with tauric acid and its physico-chemical and biological properties were evaluated. The derivative has reasonably good solubility in organic solvents. The partition coefficient values in chloroform/water 1.17 and octanol/water 1.16 systems indicate its good distribution in various tissues in vivo. The in vitro antimicrobial potency of the derivative (833.33 microg mg(-1)) is higher than that of the existing derivatives such as erythromycin estolate, erythromycin stearate, erythromycin ethyl succinate, erythromycin gluceptate, erythromycin lactobionate. The antimicrobial spectrum is comparable to that of the parent compound. Our results indicate that erythromycin taurate has a high potential for possible clinical application and is more efficient against Escherichia coli and Klebsiella pneumoniae than the parent base. 相似文献
34.
Fine mapping of the 11q22-23 tumor suppressive region and involvement of TSLC1 in nasopharyngeal carcinoma 总被引:4,自引:0,他引:4
Lung HL Cheng Y Kumaran MK Liu ET Murakami Y Chan CY Yau WL Ko JM Stanbridge EJ Lung ML 《International journal of cancer. Journal international du cancer》2004,112(4):628-635
Previous studies transferring an intact chromosome 11 into HONE1 cells demonstrated the functional significance of chromosome regions, 11q13 and 11q22-23, in nasopharyngeal carcinoma (NPC) development. In our study the 11q22-23 region was comprehensively re-investigated by detailed microsatellite and single nucleotide polymorphism genotyping and by fluorescence in situ hybridization to map precisely the regions containing tumor suppressive activity. We observed 3 chromosomal intervals within 11q22-23 that were commonly lost in the tumor segregants derived from HONE1/chromosome 11 hybrids. One critical region of 0.36 Mb was mapped near the marker D11S2000 and a second 0.44 Mb region was located around the markers D11S1300 and D11S1391. In a third region high allelic loss was also observed at marker D11S4484, where a newly cloned tumor suppressor gene, TSLC1 (tumor suppressor in lung cancer 1), is located. The gene expression analysis showed absence or low expression levels of TSLC1 mRNA in 4 highly tumorigenic NPC cell lines. In addition, the methylation study results show that the TSLC1 promoter region was hypermethylated in all 4 NPC cell lines and re-expression of the gene occurs in HONE1 cells after 5-aza-2'-deoxycytidine treatment. Hence, the mode of silencing of this candidate TSG in NPC may be attributed to promoter hypermethylation. We have obtained functional evidence for multiple critical tumor suppressive regions in 11q22-23 by fine deletion mapping and for inactivation of TSLC1 being one of these candidate TSGs in NPC development. 相似文献
35.
Deiva K Geeraerts T Salim H Leclerc P Héry C Hugel B Freyssinet JM Tardieu M 《The European journal of neuroscience》2004,20(12):3222-3232
Our purpose was to investigate in human neurons the neuroprotective pathways induced by Fractalkine (FKN) against glutamate receptor-induced excitotoxicity. CX(3)CR1 and FKN are expressed constitutively in the tested human embryonic primary neurons and SK-N-SH, a human neuroblastoma cell line. Microfluorometry assay demonstrated that CX(3)CR1 was functional in 44% of primary neurons and in 70% of SK-N-SH. Fractalkine induced ERK1/2 phosphorylation within 1 min and Akt phosphorylation after 10 min, and both phosphorylation decreased after 20 min. No p38 and SAPK/JNK activation was observed after FKN treatment. Application of FKN triggered a 53% reduction of the NMDA-induced neuronal calcium influx, which was insensitive to pertussis toxin and LY294002 an inhibitor of Akt pathway, but abolished by PD98059, an ERK1/2 pathway inhibitor. Moreover, FKN significantly reduced neuronal NMDA-induced apoptosis, which was pertussis toxin insensitive and abolished in presence of PD98059 and LY294002. In conclusion, FKN protected human neurons from NMDA-mediated excitotoxicity in at least two ways with different kinetics: (i) an early ERK1/2 activation which reduced NMDA-mediated calcium flux; and (ii), a late Akt activation associated with the previously induced ERK1/2 activation. 相似文献
36.
37.
Zhao J Lou Y Pinczewski J Malkevitch N Aldrich K Kalyanaraman VS Venzon D Peng B Patterson LJ Edghill-Smith Y Woodward R Pavlakis GN Robert-Guroff M 《Vaccine》2003,21(25-26):4022-4035
Previous non-human primate studies have shown replication competent adenovirus (Ad) HIVenv/rev and SIVenv/rev recombinants to be promising vaccine candidates. To broaden induced immunity in rhesus macaques, an Ad type 5 host range (Ad5hr) mutant vector with an inserted SIV gag gene was added to the vaccine regimen. Immunity to the encoded SIV Env, Rev, and Gag gene products was evaluated following two immunizations with the same recombinants. The vaccines were administered intranasally plus orally via stomach tube at weeks 0 and 12. The recombinants replicated well in the upper respiratory tract but poorly in the gut, suggesting enteric-coated capsules might improve oral delivery to the intestine. SIV-specific cellular immunity was induced in all 16 immunized macaques. Fourteen exhibited positive interferon-gamma (IFN-gamma) ELISPOT responses, and nine, including two lacking IFN-gamma responses, exhibited SIV-specific T-cell proliferative activity. IFN-gamma secreting peripheral blood mononuclear cells (PBMCs) in response to SIV Gag, Env, and Rev peptides were induced in 73, 53, and 27% of macaques, respectively, and were boosted two- to four-fold by the second immunization. A persistent response to Gag was evident at least 10 weeks thereafter. p11C tetramer staining confirmed elicitation of SIV Gag-specific CD8+ T-cells in Mamu-A*01 macaques. Proliferative responses were more frequent after the second immunization, and binding antibody titers to SIV gp120 were significantly boosted by the immunization regimen. We conclude that a second administration of recombinants based in the same Ad5hr vector can effectively boost immunity to inserted gene products, obviating development of several recombinants in different Ad serotypes for multiple immunizations. 相似文献
38.
Ghosh S Shinde SC Kumaran GS Sapre RS Dhond SR Badrinath Y Ansari R Kumar A Mahadik S Chougule AB Nair CN 《Indian journal of cancer》2003,40(2):71-76
OBJECTIVES: To study the hematologic and immunophenotypic profile of 260 cases of acute myeloid leukemia at diagnosis. MATERIAL AND METHODS: This is a retrospective analysis of 260 cases of AML diagnosed at our institution between 1998 and 2000. Diagnosis was based on peripheral blood and bone marrow examination for morphology cytochemistry and immunophenotypic studies. SPSS software package, version 10, was used for statistical analysis. RESULTS: Seventy-six percent of our cases were adults. The age of the patients ranged from one year to 78 years with a median age of 27.2 years. There were 187 males and 73 females. The commonest FAB subtype, in both children and adults, was AML-M2. The highest WBC counts were seen in AML-M1 and the lowest in AML-M3 (10-97 x 10(9)/L, mean 53.8 x 10(9)/L). The mean values and range for hemoglobin was 6.8 gm/l (1.8 gm/l to 9.2 gm/l), platelet count 63.3 x 10(9)/L (32-83 x 10(9)/L), peripheral blood blasts 41.4% (5 to 77%) and bone marrow blasts 57.6% (34-96%). Myeloperoxidase positivity was highest in the M1, M2 and M3 subtypes. CD13 and CD33 were the most useful markers in the diagnosis of AML. CD14 and CD36 were most often seen in monocytic (38%) and myelomonocytic (44%) leukemias. Lymphoid antigen expression was seen in 15% of cases. CD7 expression was the commonest (11%). CONCLUSION: AML accounted for 39.8% of all acute leukemias at this institution. The most common subtype was AML-M2. Myeloperoxidase stain was a useful tool in the diagnosis of myeloid leukemias. CD13 and CD33 were the most diagnostic myeloid markers. 相似文献
39.
Meena Kalyanaraman William M DeCampli Andrew I Campbell Utpal Bhalala Terry G Harmon Penelope Sandiford Claire K McMahon Shirah Shore Timothy S Yeh 《Pediatric critical care medicine》2008,9(3):285-288
OBJECTIVE: To assess the role of serial lactate levels in determining outcome after cardiopulmonary bypass surgery in children. DESIGN: Analysis of retrospectively collected data. SETTING: Cardiac intensive care unit of a tertiary care children's hospital. PATIENTS: Patients were 129 children who underwent surgery for congenital cardiac defects. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Patients were categorized for disease severity using the Risk Adjustment for Congenital Heart Surgery method. Blood lactate levels were obtained at admission to the cardiac intensive care unit and then serially until they were <2 mmol/L. Lactime, time during which the lactate remains >2 mmol/L, was noted for each patient. The primary outcome measured was mortality. Secondary outcomes measured were ventilator days and hospital days. Six patients died, and of these five were neonates. Nonsurvivors had higher initial postoperative lactate concentration (p = .01), peak postoperative lactate concentration (p = .003), and lactime (p = .05). In binomial logistic regression analysis, lactime was the strongest predictor of mortality (p = .03). The positive predictive value for all age groups was highest for lactime >48 hrs, with a positive predictive value of 60%, and among the neonates it was 75%. Initial lactate level >6 mmol/L had a positive predictive value of only 6%, and the peak lactate level >6 mmol/L had a positive predictive value of only 15%. Lactime also had a significant association with ventilator days and hospital days among the survivors (p = .001). CONCLUSIONS: Lactime was a useful predictor of mortality in children undergoing repair or palliation of congenital cardiac defects under cardiopulmonary bypass. Initial and peak lactate levels had a poor positive predictive value for mortality. Lactime also was associated with the number of ventilator days and hospital days in those who survived. 相似文献
40.
Lynn Joanne; Cobbs Elizabeth; Orenstein Jan; Madigan Coleen M.; Atkins Carl D.; Goldhahn Jr Richard T.; Sangani Bakul; Kalyanaraman Venkataraman; Bhargava Mukesh; Dwek Joe H.; Bewtra Chhanda; Gistrak Michael; Saqi Anjali; Hoda Syed A.; Machin Tomas; Wecht Cyril H.; Burton Elizabeth C. 《JAMA》1999,281(23):2181-2181; author reply 2185