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121.
Marie Olszewski Pauline M Chou Wei Huang Sarah Tallman Morris Kletzel 《Pediatric and developmental pathology》2006,9(3):203-209
An important measure to ensure successful follow-up in patients with allogeneic stem cell transplant is to evaluate for engraftment. Recent studies have shown that detecting minimal residual disease is important in order to predict early clinical relapse. We followed 88 leukemic patients with pre- and posttransplant Wilms tumor gene (WT1) levels to predict relapse and variable number of tandem repeats (VNTR) for engraftment. We have found that high pretransplant WT1 levels correlated significantly with relapse in all patient groups, but more significantly in the acute nonlymphoblastic leukemia (ANLL) patients. Posttransplant WT1 level correlated with VNTR status such that low WT1 is associated invariably with VNTR of 100% donor origin, while high WT1 is associated with VNTR of 20%. The association is significant in all patients, specifically in ANLL patients. In this preliminary study, we demonstrate that patients harboring detectable levels of WT1 prior to stem cell transplant have a higher chance of relapse, and posttransplant WT1 and VNTR status appeared to be dependent parameters predicting relapse when present in the posttransplant period. By combining 2 highly sensitive molecular techniques, we have found that this combined technique provided us with a promising alternative for overcoming the limitations imposed by each separate procedure. More studies are necessary before we can come to any significant conclusions. 相似文献
122.
Recent advances in modern perinatal and neonatal intensive care have led to an increase in the survival of premature infants. This increased survival, unfortunately, has not been accompanied by an improvement in neurodevelopmental outcomes. Premature infants, especially those with an extremely low birth weight (less than 1000 g) or those born at less than 28 weeks’ gestation, are at increased risk of major disabilities and complex, ‘low severity’ dysfunctions that have significant, lasting effects on their school function, academic performance and behaviour, as well as on family function. Neonatal follow-up programs provide a number of functions to centres providing neonatal intensive care, including quality assurance and audits, research and follow-up clinical care to neonatal intensive care unit survivors and their families. The challenge for neonatal follow-up programs is to meet the often competing objectives of providing clinical services to children and their families while providing quality assurance and audits, and high-quality long-term outcome research components, given the available resources. There is also a need for ongoing research to develop and evaluate effective postdischarge intervention programs to improve the long-term outcome of prematurity and other neonatal complications. Developmental paediatricians – with their background and training in the provision of specialized health care to children and their care-givers with respect to developmental and psychosocial well-being, and in conducting developmental and behavioural disabilities research – play a valuable role in the follow-up assessment and care of neonatal intensive care unit graduates, and strengthen the multidisciplinary research groups necessary to assess long-term outcomes and the effects of perinatal and postdischarge interventions. 相似文献
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Ruth Etzioni Sarah Hawley Dean Billheimer Lawrence D True Beatrice Knudsen 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1040-1046
BACKGROUND: Immunohistochemical studies use antibodies to stain tissues with the goal of quantifying protein expression. However, protein expression is often heterogeneous resulting in variable degrees and patterns of staining. This problem is particularly acute in prostate cancer, where tumors are infiltrative and heterogeneous in nature. In this article, we introduce analytic approaches that explicitly consider both the frequency and intensity of tissue staining. METHODS: Compositional data analysis is a technique used to analyze vectors of unit-sum proportions, such as those obtained from soil sample studies or species abundance surveys. We summarized specimen staining patterns by the proportion of cells staining at mild, moderate, and intense levels and used compositional data analysis to summarize and compare the resulting staining profiles. RESULTS: In a study of Syndecan-1 staining patterns among 44 localized prostate cancer cases with Gleason score 7 disease, compositional data analysis did not detect a statistically significant difference between the staining patterns in recurrent (n = 22) versus nonrecurrent (n = 22) patients. Results indicated only modest increases in the proportion of cells staining at a moderate intensity in the recurrent group. In contrast, an analysis that compared quantitative scores across groups indicated a (borderline) significant increase in staining in the recurrent group (P = 0.05, t test). CONCLUSIONS: Compositional data analysis offers a novel analytic approach for immunohistochemical studies, providing greater insight into differences in staining patterns between groups, but possibly lower statistical power than existing, score-based methods. When appropriate, we recommend conducting a compositional data analysis in addition to a standard score-based analysis. 相似文献
126.
Alcohol, ALDH2, and esophageal cancer: a meta-analysis which illustrates the potentials and limitations of a Mendelian randomization approach. 总被引:2,自引:0,他引:2
Mendelian randomization, the use of common polymorphisms as surrogates for measuring exposure levels in epidemiologic studies, provides one method of assessing the causal nature of some environmental exposures. This can be illustrated by looking at the association between the ALDH2 polymorphism and esophageal cancer. Alcohol drinking is considered a risk factor for esophageal cancer, and exposure to high levels of acetaldehyde, the principal metabolite of alcohol, may be responsible for the increased cancer risk. The ability to metabolize acetaldehyde is encoded by the ALDH2 gene, which is polymorphic in some populations. The ALDH2*2 allele produces an inactive protein subunit, which is unable to metabolize acetaldehyde. An individual's genotype at this locus may influence their esophageal cancer risk through two mechanisms, first through influencing alcohol intake and second through influencing acetaldehyde levels. We have carried out a meta-analysis of studies looking at the ALDH2 genotype and esophageal cancer and found that risk was reduced among *2*2 homozygotes [odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.16-0.80] and increased among heterozygotes (OR, 3.19; 95% CI, 1.86-5.47) relative to *1*1 homozygotes. This provides strong evidence that alcohol intake increases the risk of esophageal cancer and individuals whose genotype results in markedly lower intake, because they have an adverse reaction to alcohol are thus protected. This meta-analysis also provides evidence that acetaldehyde plays a carcinogenic role in esophageal cancer. The two different processes operating as a result of the ALDH2 genotype have implications for the interpretation of studies using the Mendelian randomization paradigm. 相似文献
127.
Kazuaki Takabe MD PhD Waddah Al-Refaie Brian Chin Pauline K. Chu Stephen M. Baird Sarah L. Blair 《Journal of gastrointestinal cancer》2005,35(1):83-88
A 58-yr-old male with a history of hepatitis C virus infection, presented with a 2-mo history of intractable left upper abdominal pain. He had fallen from a ladder 2 yr previously, landing on his left side. Abdominal computed tomography identified a large cystic mass in the spleen. The patient was brought to the operating room with a presumptive diagnosis of symptomatic, post-traumatic, false cyst of the spleen. Instead, at surgery, a splenic mass with dense adhesions to the diaphragm and stomach was found. On final histological analysis, it was diagnosed to be a large B-cell lymphoma. Despite its rarity, gastroenterologists and surgeons should be aware of large B-cell lymphoma when encountering cystic lesions of the spleen, because the management of benign cystic disease is usually nonsurgical. 相似文献
128.
Roy Kakali Satapathy Amit Kumar Houhton Jayne A. L. Flanagan Sarah E. Radha Venkatesan Mohan Viswanathan Sharma Rajni Jain Vandana 《Indian journal of pediatrics》2019,86(11):1051-1053
Indian Journal of Pediatrics - Congenital hyperinsulinism (CHI) is a clinically and genetically heterogeneous disorder, characterized by dysregulated insulin secretion. Pathogenic variants in at... 相似文献
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Ilona Krey Sarah von Spiczak Kathrine M. Johannesen Christiane Hikel Gerhard Kurlemann Hiltrud Muhle Diane Beysen Tobias Dietel Rikke S. Mller Johannes R. Lemke Steffen Syrbe 《Neurotherapeutics》2022,19(1):334
Pathogenic missense variants in GRIN2A and GRIN2B may result in gain or loss of function (GoF/LoF) of the N-methyl-D-aspartate receptor (NMDAR). This observation gave rise to the hypothesis of successfully treating GRIN-related disorders due to LoF variants with co-agonists of the NMDAR. In this respect, we describe a retrospectively collected series of ten individuals with GRIN2A- or GRIN2B-related disorders who were treated with L-serine, each within an independent n-of-1 trial. Our cohort comprises one individual with a LoF missense variant with clinical improvements confirming the above hypothesis and replicating a previous n-of-1 trial. A second individual with a GoF missense variant was erroneously treated with L-serine and experienced immediate temporary behavioral deterioration further supporting the supposed functional pathomechanism. Eight additional individuals with null variants (that had been interpreted as loss-of-function variants despite not being missense) again showed clinical improvements. Among all nine individuals with LoF missense or null variants, L-serine treatment was associated with improvements in behavior in eight (89%), in development in four (44%), and/or in EEG or seizure frequency in four (44%). None of these nine individuals experienced side effects or adverse findings in the context of L-serine treatment. In summary, we describe the first evidence that L-serine treatment may not only be associated with clinical improvements in GRIN-related disorders due to LoF missense but particularly also null variants.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-021-01173-9. 相似文献