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Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
94.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases. 相似文献
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96.
Intraoperative radioisotope sentinel lymph node mapping in non-small cell lung cancer 总被引:9,自引:0,他引:9
Liptay MJ Masters GA Winchester DJ Edelman BL Garrido BJ Hirschtritt TR Perlman RM Fry WA 《The Annals of thoracic surgery》2000,70(2):384-9; discussion 389-90
BACKGROUND: Lymph node metastases are the most significant prognostic factor in localized non-small cell lung cancer (NSCLC). Nodal micrometastases may not be detected. Identification of the first nodal drainage site (sentinel node) may improve detection of metastatic nodes. We performed intraoperative Technetium 99m sentinel lymph node (SN) mapping in patients with resectable NSCLC. METHODS: Fifty-two patients (31 men, 21 women) with resectable suspected NSCLC were enrolled. At thoracotomy, the primary tumor was injected with 2 mCi Tc-99. After dissection, scintographic readings of both the primary tumor and lymph nodes were obtained with a handheld gamma counter. Resection with mediastinal node dissection was performed and findings were correlated with histologic examination. RESULTS: Seven of the 52 patients did not have NSCLC (5 benign lesions, and 2 metastatic tumors) and were excluded. Forty-five patients had NSCLC completely resected. Mean time from injection of the radionucleide to identification of sentinel nodes was 63 minutes (range 23 to 170). Thirty-seven patients (82%) had a SN identified; 12 (32%) had metastatic disease. 35 of the 37 SNs (94%) were classified as true positive with no metastases found in other intrathoracic lymph nodes without concurrent SN involvement. Two inaccurately identified SNs were encountered (5%). SNs were mediastinal (N2) in 8 patients (22%). CONCLUSIONS: Intraoperative SN mapping with Tc-99 is an accurate way to identify the first site of potential nodal metastases of NSCLC. This method may improve the precision of pathologic staging and limit the need for mediastinal node dissection in selected patients. 相似文献
97.
98.
新近的临床试验资料,包括2009年美国临床肿瘤协会(ASCO)年会上报道的资料,有力地推动了对晚期非小细胞肺癌(NSCLC)患者的现代治疗策略的改革。此改革蕴含的主题包括:(1)基于组织学类型的治疗,(2)预 相似文献
99.
Skinner J Mee TJ Blackwell RP Maslanyj MP Simpson J Allen SG Day NE Cheng KK Gilman E Williams D Cartwright R Craft A Birch JM Eden OB McKinney PA Deacon J Peto J Beral V Roman E Elwood P Alexander FE Mott M Chilvers CE Muir K Doll R Taylor CM Greaves M Goodhead D Fry FA Adams G Law G;United Kingdom Childhood Cancer Study Investigators 《British journal of cancer》2002,87(11):1257-1266
The United Kingdom Childhood Cancer Study, a population-based case-control study covering the whole of Great Britain, incorporated a pilot study measuring electric fields. Measurements were made in the homes of 473 children who were diagnosed with a malignant neoplasm between 1992 and 1996 and who were aged 0-14 at diagnosis, together with 453 controls matched on age, sex and geographical location. Exposure assessments comprised resultant spot measurements in the child's bedroom and the family living-room. Temporal stability of bedroom fields was investigated through continuous logging of the 48-h vertical component at the child's bedside supported by repeat spot measurements. The principal exposure metric used was the mean of the pillow and bed centre measurements. For the 273 cases and 276 controls with fully validated measures, comparing those with a measured electric field exposure >/=20 V m(-1) to those in a reference category of exposure <10 V m(-1), odds ratios of 1.31 (95% confidence interval 0.68-2.54) for acute lymphoblastic leukaemia, 1.32 (95% confidence interval 0.73-2.39) for total leukaemia, 2.12 (95% confidence interval 0.78-5.78) for central nervous system cancers and 1.26 (95% confidence interval 0.77-2.07) for all malignancies were obtained. When considering the 426 cases and 419 controls with no invalid measures, the corresponding odds ratios were 0.86 (95% confidence interval 0.49-1.51) for acute lymphoblastic leukaemia, 0.93 (95% confidence interval 0.56-1.54) for total leukaemia, 1.43 (95% confidence interval 0.68-3.02) for central nervous system cancers and 0.90 (95% confidence interval 0.59-1.35) for all malignancies. With exposure modelled as a continuous variable, odds ratios for an increase in the principal metric of 10 V m(-1) were close to unity for all disease categories, never differing significantly from one. 相似文献
100.
Barbara Jones Nancy Cincotta Wendy Pelletier Abigail Fry Lori Wiener 《Current oncology (Toronto, Ont.)》2022,29(9):6177
Background: The COVID-19 pandemic has significantly altered the lives of pediatric oncology social workers. Challenges include difficulty building rapport with the use of telephone/computers, lack of clarity around who is designated as “essential”, structural challenges, isolation, and witnessing distress. This study aimed to describe the ways that the pandemic has personally impacted pediatric oncology social workers. Methods: Participants were recruited through the Association of Pediatric Oncology Social Workers (APOSW) listserv. In total, 101 participants from 31 states and the District of Columbia completed an online survey containing quantitative and open-ended questions. Qualitative data analysis included thematic analysis of participants’ optional survey responses to three open-ended questions. Results: Fifty-seven of the participants provided responses that revealed 3 first level codes and 11 second level codes. First level codes were developed a priori from the questions: Experiences that stay with you, Wisdom gained and Impact on your work. Pandemic-related challenges caused moral suffering and professional challenges for participants but also created opportunities to find meaning in their work. Conclusion: Data illuminated moral suffering, unrecognized resilience, new ways of maintaining self-and family care, and creative approaches to care of children with cancer and their families at diagnosis, during treatments and at the end of life. 相似文献