Results of Molecular Monitoring in Posttransplant Period by Means of Series Investigation of WT1 Gene Expression in Patients with Acute Myeloid Leukemia

Aim. To demonstrate diagnostic and prognostic significance of series measurement of WT1 expression in patients with acute myeloid leukemia (AML) after allogenic hematopoietic stem cell transplantation (allo-HSCT). Materials & Methods. The clinical trial included 88 AML patients (38 females (43 %) and 50 males (57 %) aged 2–68, median 30 years). All the patients received allo-HSCT. Bone marrow was aspirated before (D0) and after HSCT (D+30, D+60, and D+100). Results. The univariate analysis showed statistically significant differences in 2-year overall survival with respect to the following factors: with and without remission at the moment of HSCT (p 250 copies before HSCT (p < 0.001) and at time points D+60 (p = 0.012), and D+100 (p < 0.001). Multivariate analysis revealed similar statistical significance of differences among patients transplanted in remission (p = 0.041) and with cGVHD (p = 0.03). In univariate analysis statistically significant differences in 2-year event-free survival (EFS) were found: a) in patients with allo-HSCT, either in remission or not (p < 0.001); b) using HSC, but not bone marrow, as transplant source (p < 0.026); c) with normal or high WT1 expression at the stage of HSCT (p < 0.001) and at time point D+100 (p < 0.001); d) using HSC from related or unrelated donor (p = 0.006); e) in patients with cGVHD (p = 0.05). In multivariate analysis independent positive effect on EFS was observed only in patients with normal WT1 expression at D+100 (p = 0.011) and with cGVHD (p = 0.038). Cumulative incidence of posttransplant relapse (PTR) in AML patients with normal or high WT1 expression at the stage of HSCT within the 2-year follow-up was significantly different (28.2 vs. 58.9 %; p = 0.002), also in measurements of this parameter at D+60 and D+100 (p = 0.015 and p < 0.001, respectively). In 1/4 of patients cytological relapses (cPTR) appeared considerably later than molecular relapses (mPTR), i.e. 13–489 days later (median 35 days), which is accounted for by early preventive therapy aimed at cPTR prophylaxis against the background of already recorded mPTR. According to our data, GVHD plays a crucial role in cPTR management. Conclusion. Phenomenon of WT1 expression normalization after allo-HSCT in AML patients proves to have a high diagnostic and prognostic significance. Introduction of this approach into clinical practice seems highly advisable for national oncohematological centers

Efficacy of Chemotherapy in Acute Leukemia Patients Resistant to Previous Standard Treatment According to the Series Measurement of WT1 Gene Expression

Aim. To estimate the efficacy of chemotherapy in acute leukemia patients resistant to previous standard treatment according to the series measurement of WT1 expression. Materials & Methods. The series measurement of WT1 expression formed the basis of the efficacy estimation of induction chemotherapy in 31 patients (15 men and 16 women aged from 3 months to 68 years; the median age was 28 years) with prognostically unfavourable variants of acute myeloid (AML) and lymphoblastic leukemia (ALL) (23 AML and 8 ALL patients). The WT1 gene expression was measured at baseline and 2–3 weeks after the treatment by the quantitative real-time PCR. The threshold level for detection was 250 copies of WT1/104 copies of ABL. The cytogenetic profile of leukemia cells was assessed by standard cytogenetics and FISH. Results. The baseline expression level of WT1 varied from 305 to 58,569 copies/104 copies of ABL. The expected reduction of WT1 expression after the first induction chemotherapy treatment was reported in 22/23 (96 %) AML patients and in 6/8 (75 %) ALL patients. According to our results WT1 expression reached the threshold in 13/31 (42 %) patients, including 9 AML patients and 4 ALL patients. After 11/31 (35 %) patients received the second course of treatment, WT1 expression level became normal in 8 cases (5 ALL and 3 AML patients). Despite high dose chemotherapy, HSCT and such agents as blinatumomab and gemtuzumab, an unfavourable outcome was observed in 18/31 (58 %) patients including 6 patients with complex karyotype (CK+) and 2 patients with monosomal karyotype (MK+). Once the MK+ and CK+ combination was observed, in another case the MK+ was combined with the prognostically unfavourable inv(3)(q21q26) inversion. Conclusion. Our results show that the molecular monitoring should be included as part of treatment of the prognostically unfavourable acute leukemia. The WT1 gene was shown to be the most appropriate marker. WT1 expression was shown to correlate with the common fusion genes allowing to estimate the blast cell count at the molecular level

eXtraembryonic ENdoderm (XEN) Stem Cells Produce Factors that Activate Heart Formation

Initial specification of cardiomyocytes in the mouse results from interactions between the extraembryonic anterior visceral endoderm (AVE) and the nascent mesoderm. However the mechanism by which AVE activates cardiogenesis is not well understood, and the identity of specific cardiogenic factors in the endoderm remains elusive. Most mammalian studies of the cardiogenic potential of the endoderm have relied on the use of cell lines that are similar to the heart-inducing AVE. These include the embryonal-carcinoma-derived cell lines, END2 and PYS2. The recent development of protocols to isolate eXtraembryonic ENdoderm (XEN) stem cells, representing the extraembryonic endoderm lineage, from blastocyst stage mouse embryos offers new tools for the genetic dissection of cardiogenesis.Here, we demonstrate that XEN cell-conditioned media (CM) enhances cardiogenesis during Embryoid Body (EB) differentiation of mouse embryonic stem (ES) cells in a manner comparable to PYS2-CM and END2-CM. Addition of CM from each of these three cell lines enhanced the percentage of EBs that formed beating areas, but ultimately, only XEN-CM and PYS2-CM increased the total number of cardiomyocytes that formed. Furthermore, our observations revealed that both contact-independent and contact-dependent factors are required to mediate the full cardiogenic potential of the endoderm. Finally, we used gene array comparison to identify factors in these cell lines that could mediate their cardiogenic potential.These studies represent the first step in the use of XEN cells as a molecular genetic tool to study cardiomyocyte differentiation. Not only are XEN cells functionally similar to the heart-inducing AVE, but also can be used for the genetic dissection of the cardiogenic potential of AVE, since they can be isolated from both wild type and mutant blastocysts. These studies further demonstrate the importance of both contact-dependent and contact-independent factors in cardiogenesis and identify potential heart-inducing proteins in the endoderm

A Comparative Analysis of Extra-Embryonic Endoderm Cell Lines

Prior to gastrulation in the mouse, all endodermal cells arise from the primitive endoderm of the blastocyst stage embryo. Primitive endoderm and its derivatives are generally referred to as extra-embryonic endoderm (ExEn) because the majority of these cells contribute to extra-embryonic lineages encompassing the visceral endoderm (VE) and the parietal endoderm (PE). During gastrulation, the definitive endoderm (DE) forms by ingression of cells from the epiblast. The DE comprises most of the cells of the gut and its accessory organs. Despite their different origins and fates, there is a surprising amount of overlap in marker expression between the ExEn and DE, making it difficult to distinguish between these cell types by marker analysis. This is significant for two main reasons. First, because endodermal organs, such as the liver and pancreas, play important physiological roles in adult animals, much experimental effort has been directed in recent years toward the establishment of protocols for the efficient derivation of endodermal cell types in vitro. Conversely, factors secreted by the VE play pivotal roles that cannot be attributed to the DE in early axis formation, heart formation and the patterning of the anterior nervous system. Thus, efforts in both of these areas have been hampered by a lack of markers that clearly distinguish between ExEn and DE. To further understand the ExEn we have undertaken a comparative analysis of three ExEn-like cell lines (END2, PYS2 and XEN). PYS2 cells are derived from embryonal carcinomas (EC) of 129 strain mice and have been characterized as parietal endoderm-like [1], END2 cells are derived from P19 ECs and described as visceral endoderm-like, while XEN cells are derived from blastocyst stage embryos and are described as primitive endoderm-like. Our analysis suggests that none of these cell lines represent a bona fide single in vivo lineage. Both PYS2 and XEN cells represent mixed populations expressing markers for several ExEn lineages. Conversely END2 cells, which were previously characterized as VE-like, fail to express many markers that are widely expressed in the VE, but instead express markers for only a subset of the VE, the anterior visceral endoderm. In addition END2 cells also express markers for the PE. We extended these observations with microarray analysis which was used to probe and refine previously published data sets of genes proposed to distinguish between DE and VE. Finally, genome-wide pathway analysis revealed that SMAD-independent TGFbeta signaling through a TAK1/p38/JNK or TAK1/NLK pathway may represent one mode of intracellular signaling shared by all three of these lines, and suggests that factors downstream of these pathways may mediate some functions of the ExEn. These studies represent the first step in the development of XEN cells as a powerful molecular genetic tool to study the endodermal signals that mediate the important developmental functions of the extra-embryonic endoderm. Our data refine our current knowledge of markers that distinguish various subtypes of endoderm. In addition, pathway analysis suggests that the ExEn may mediate some of its functions through a non-classical MAP Kinase signaling pathway downstream of TAK1

Reconstructing Asian faunal introductions to eastern Africa from multi-proxy biomolecular and archaeological datasets

Human-mediated biological exchange has had global social and ecological impacts. In subS-aharan Africa, several domestic and commensal animals were introduced from Asia in the pre-modern period; however, the timing and nature of these introductions remain contentious. One model supports introduction to the eastern African coast after the mid-first millennium CE, while another posits introduction dating back to 3000 BCE. These distinct scenarios have implications for understanding the emergence of long-distance maritime connectivity, and the ecological and economic impacts of introduced species. Resolution of this longstanding debate requires new efforts, given the lack of well-dated fauna from high-precision excavations, and ambiguous osteomorphological identifications. We analysed faunal remains from 22 eastern African sites spanning a wide geographic and chronological range, and applied biomolecular techniques to confirm identifications of two Asian taxa: domestic chicken (Gallus gallus) and black rat (Rattus rattus). Our approach included ancient DNA (aDNA) analysis aided by BLAST-based bioinformatics, Zooarchaeology by Mass Spectrometry (ZooMS) collagen fingerprinting, and direct AMS (accelerator mass spectrometry) radiocarbon dating. Our results support a late, mid-first millennium CE introduction of these species. We discuss the implications of our findings for models of biological exchange, and emphasize the applicability of our approach to tropical areas with poor bone preservation

Advances in structure elucidation of small molecules using mass spectrometry

The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, isotopic abundance accuracy, accurate mass multiple-stage MS(n) capability, as well as hybrid mass spectrometric and orthogonal chromatographic approaches. The latter part discusses mass spectral data handling strategies, which includes background and noise subtraction, adduct formation and detection, charge state determination, accurate mass measurements, elemental composition determinations, and complex data-dependent setups with ion maps and ion trees. The importance of mass spectral library search algorithms for tandem mass spectra and multiple-stage MS(n) mass spectra as well as mass spectral tree libraries that combine multiple-stage mass spectra are outlined. The successive chapter discusses mass spectral fragmentation pathways, biotransformation reactions and drug metabolism studies, the mass spectral simulation and generation of in silico mass spectra, expert systems for mass spectral interpretation, and the use of computational chemistry to explain gas-phase phenomena. A single chapter discusses data handling for hyphenated approaches including mass spectral deconvolution for clean mass spectra, cheminformatics approaches and structure retention relationships, and retention index predictions for gas and liquid chromatography. The last section reviews the current state of electronic data sharing of mass spectra and discusses the importance of software development for the advancement of structure elucidation of small molecules

Depressive symptoms and cognitive performance of the elderly: relationship between institutionalization and activity programs Sintomas depressivos e desempenho cognitivo nos idosos: relações entre institucionalização e realização de atividades

OBJECTIVE: The aim of this study was to assess the frequency of depressive symptoms and to evaluate cognitive performance of institutionalized versus non-institutionalized elderly subjects and to compare the effect of institutionalization and participation in the institution's activity programs on their cognitive performance. METHOD: A group of 120 elderly subjects with a mean age of 71 years and average schooling of 4.2 years was evaluated. The participants were divided into 3 groups: non-institutionalized (n = 37); institutionalized with activities (n = 37); institutionalized without activities (n = 46). The groups were matched for age, gender and educational level. The following assessment instruments were used: the Geriatric Depression Scale, the Mini-Mental State Examination, the Verbal Fluency Test and the computerized versions of the Hooper Visual Organization Test and the Boston Naming Test. The data were analyzed using one-way ANOVA and the Pearson's correlation test. RESULTS: The two groups of institutionalized elderly showed higher frequency of depressive symptoms when compared to non-institutionalized subjects and worse performance on the Verbal Fluency Test. The institutionalized group without activities had lower scores on Mental State Examination, Boston Naming Test and Hooper Visual Organization Test when compared to the other two groups (p < 0.05). CONCLUSIONS: Institutionalization of the elderly seems to be related to worse cognitive performance. Activity programs during institutionalization may be effective in minimizing cognitive functional loss.<br>OBJETIVO: Avaliar a freqüência de sintomas depressivos e o desempenho cognitivo de idosos institucionalizados e não institucionalizados. Comparar os escores nos testes em função da institucionalização e da realização de atividades oferecidas pela instituição. MÉTODO: Foram avaliados 120 idosos com idade média de 71 anos e escolaridade média de 4,2 anos, divididos em três grupos: Não institucionalizados (n = 37); Institucionalizados com atividade (n = 37); Institucionalizados sem atividade (n = 46). Os grupos foram pareados em função da idade, sexo e escolaridade. Foram aplicados os instrumentos: Escala de Depressão Geriátrica, Mini-Exame do Estado Mental, Teste de Fluência Verbal e as versões computadorizadas do Teste Hooper de Organização Visual e do teste de Nomeação de Boston. Foram conduzidas ANOVAs unifatoriais e o teste de correlação de Pearson. RESULTADOS: Os dois grupos de idosos institucionalizados apresentaram maior freqüência de depressão e pior desempenho na prova de fluência verbal. Idosos de instituição sem atividade tiveram desempenho inferior aos outros dois grupos nos testes Mini-Exame do Estado Menatal, Teste de Nomeação de Boston e Hooper (p < 0,05). CONCLUSÃO: Pior desempenho cognitivo dos idosos parece estar relacionado com a institucionalização. As atividades diárias de estimulação podem ser eficientes em minimizar as perdas cognitivas dos idosos institucionalizados