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1.
Cancer ; 129(16): 2491-2498, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37282609

RESUMO

BACKGROUND: Chromosome 1 abnormalities in multiple myeloma (MM) are increasingly recognized as high risk-defining features. The authors report the prognostic value of del(1p13.3) by fluorescence in situ hybridization (FISH) at enrollment in subjects treated on total therapy clinical trials 2-6. METHODS: FISH probes were generated from specific BAC DNA clones for the AHCYL1 gene locus (1p13.3) and the CKS1B locus (1q21). RESULTS: A total of 1133 patients were included in this analysis. Although del(1p13.3) was detected in 220 (19.4%) patients, 1q21gain or 1q21amp were observed in 300 (26.5%) and 150 (13.2%) patients, respectively. Concomitant del(1p13.3) with 1q21 gain or amp was observed in 65 (5.7%) and 29 (2.5%) patients, respectively. There was enrichment of high-risk features such as International Staging System (ISS) stage 3 disease and gene expression profiling (GEP)70 high risk (HR) in the group with del(1p13.3). Presence of del(1p13.3) confers inferior progression-free survival (PFS) and overall survival (OS). On multivariate analysis, the presence of ISS stage 3 disease, GEP70 HR, 1q21gain, and 1q21amp were independent predictors of PFS or OS. CONCLUSIONS: The PFS and OS of patients with combined abnormalities of del (1p13.3)/1q21gain or amp was significantly worse compared to del(1p13.3) alone and 1q21gain or 1q21 amp alone, which identifies a subset of patients with poor clinical outcomes.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/terapia , Hibridização in Situ Fluorescente , Cromossomos Humanos Par 1/genética , Aberrações Cromossômicas , Prognóstico , Deleção Cromossômica
2.
Br J Haematol ; 189(1): 67-71, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31820442

RESUMO

Gain of chromosome 1q21 and the gene expression-based GEP70 risk score are established prognostic markers for newly diagnosed Multiple Myeloma (MM) patients. Here we addressed the prognostic impact of these two markers in 81 relapsed/refractory (RR) MM patients treated with the CD38-antibody daratumumab. Fluorescence in situ hybridization for 1q21 was performed at initial presentation, while the GEP70 score was determined at initial presentation and prior to daratumumab treatment. While the GEP70 at initial presentation showed a trend for inferior survival, the GEP70 collected prior to daratumumab treatment was significantly associated with poor outcome (P < 0·05). The worst outcome was seen for patients who were positive for gain(1q) and classified as GEP70 high risk prior to daratumumab [progression-free (PFS) and overall survival (OS) of 0·3 years (95% CI: 0·15-1·4 years) and 0·8 years (95% CI: 0·5-1·9 years) respectively], while the median PFS and OS were not reached by patients without gain(1q) and GEP70 low-risk status. In conclusion, gain(1q) and the GEP70 are powerful prognostic markers for RR MM patients treated with daratumumab, and patients classified as high risk according to these markers experience shorter treatment response.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Cromossomos Humanos Par 1/genética , Amplificação de Genes , Mieloma Múltiplo , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Medição de Risco , Taxa de Sobrevida
3.
Haematologica ; 105(4): 1055-1066, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31221783

RESUMO

MYC is a widely acting transcription factor and its deregulation is a crucial event in many human cancers. MYC is important biologically and clinically in multiple myeloma, but the mechanisms underlying its dysregulation are poorly understood. We show that MYC rearrangements are present in 36.0% of newly diagnosed myeloma patients, as detected in the largest set of next generation sequencing data to date (n=1,267). Rearrangements were complex and associated with increased expression of MYC and PVT1, but not other genes at 8q24. The highest effect on gene expression was detected in cases where the MYC locus is juxtaposed next to super-enhancers associated with genes such as IGH, IGK, IGL, TXNDC5/BMP6, FAM46C and FOXO3 We identified three hotspots of recombination at 8q24, one of which is enriched for IGH-MYC translocations. Breakpoint analysis indicates primary myeloma rearrangements involving the IGH locus occur through non-homologous end joining, whereas secondary MYC rearrangements occur through microhomology-mediated end joining. This mechanism is different to lymphomas, where non-homologous end joining generates MYC rearrangements. Rearrangements resulted in overexpression of key genes and chromatin immunoprecipitation-sequencing identified that HK2, a member of the glucose metabolism pathway, is directly over-expressed through binding of MYC at its promoter.


Assuntos
Genes myc , Mieloma Múltiplo , RNA Longo não Codificante/genética , Genes de Cadeia Pesada de Imunoglobulina , Humanos , Hibridização in Situ Fluorescente , Mieloma Múltiplo/genética , Isomerases de Dissulfetos de Proteínas , Translocação Genética
4.
Int J Mol Sci ; 21(14)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650435

RESUMO

In vertebrates, biomineralization is a feature considered unique to mature osteoblasts and odontoblasts by which they synthesize hydroxyapatite (HAP), which is deposited in the collagen matrix to construct endoskeleton. For many decades, the mechanisms that modulate differentiation and maturation of these specialized cells have been sought as a key to understanding bone-remodeling defects. Here, we report that biomineralization is an innate ability of all mammalian cells, irrespective of cell type or maturation stage. This innate biomineralization is triggered by the concomitant exposure of living cells to three indispensable elements: calcium ion, phosphoester salt, and alkaline phosphatase. Any given somatic cell, including undifferentiated mononuclear cells, can undergo a biomineralization process to produce calcium-phosphate agglomerates. The biologically generated minerals under such conditions are composed of genuine HAP crystallites of Ca10(PO4)6(OH)2 and 5-10 nanometer (nm) in size. This discovery will profoundly improve our understanding of bone metabolism and ectopic calcifications.


Assuntos
Biomineralização/fisiologia , Durapatita/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/metabolismo , Osso e Ossos/fisiologia , Fosfatos de Cálcio/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Colágeno/metabolismo , Células HEK293 , Células HL-60 , Células HeLa , Humanos , Células K562 , Células MCF-7 , Mamíferos/metabolismo , Mamíferos/fisiologia , Camundongos , Células NIH 3T3 , Odontoblastos/metabolismo , Odontoblastos/fisiologia , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Células PC-3 , Células THP-1 , Células U937
5.
Blood ; 128(13): 1735-44, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27516441

RESUMO

To elucidate the mechanisms underlying relapse from chemotherapy in multiple myeloma, we performed a longitudinal study of 33 patients entered into Total Therapy protocols investigating them using gene expression profiling, high-resolution copy number arrays, and whole-exome sequencing. The study illustrates the mechanistic importance of acquired mutations in known myeloma driver genes and the critical nature of biallelic inactivation events affecting tumor suppressor genes, especially TP53, the end result being resistance to apoptosis and increased proliferation rates, which drive relapse by Darwinian-type clonal evolution. The number of copy number aberration changes and biallelic inactivation of tumor suppressor genes was increased in GEP70 high risk, consistent with genomic instability being a key feature of high risk. In conclusion, the study highlights the impact of acquired genetic events, which enhance the evolutionary fitness level of myeloma-propagating cells to survive multiagent chemotherapy and to result in relapse.


Assuntos
Evolução Clonal , Genes Supressores de Tumor , Mieloma Múltiplo/genética , Mutação , Adulto , Idoso , Proliferação de Células , Variações do Número de Cópias de DNA , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Genes p53 , Genes ras , Instabilidade Genômica , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Fosfatidilinositol 3-Quinases/genética , Recidiva , Fatores de Risco , Transplante de Células-Tronco , Transplante Autólogo
6.
Blood ; 125(24): 3756-9, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-25943786

RESUMO

Multiple myeloma is a B-cell malignancy stratified in part by cytogenetic abnormalities, including the high-risk copy number aberrations (CNAs) of +1q21 and 17p(-). To investigate the relationship between 1q21 CNAs and DNA hypomethylation of the 1q12 pericentromeric heterochromatin, we treated in vitro peripheral blood cultures of 5 patients with balanced constitutional rearrangements of 1q12 and 5 controls with the hypomethylating agent 5-azacytidine. Using G-banding, fluorescence in situ hybridization, and spectral karyotyping, we identified structural aberrations and copy number gains of 1q21 in the treated cells similar to those found in patients with cytogenetically defined high-risk disease. Aberrations included 1q12 triradials, amplifications of regions juxtaposed to 1q12, and jumping translocations 1q12. Strikingly, all 5 patients with constitutional 1q12 rearrangements showed amplifications on the derivative chromosomes distal to the inverted or translocated 1q12 region, including MYCN in 1 case. At the same time, no amplification of the 1q21 region was found when the 1q12 region was inverted or absent. These findings provide evidence that the hypomethylation of the 1q12 region can potentially amplify any genomic region juxtaposed to it and mimic CNAs found in the bone marrow of patients with high-risk disease.


Assuntos
Cromossomos Humanos Par 1/genética , Dosagem de Genes , Mieloma Múltiplo/genética , Aberrações Cromossômicas , Metilação de DNA , Epigênese Genética , Humanos , Translocação Genética
7.
Genes Chromosomes Cancer ; 55(11): 890-901, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27311012

RESUMO

Multiple myeloma can be divided into two distinct genetic subgroups: hyperdiploid (HRD) or nonhyperdiploid (NHRD) myeloma. Myeloma cell lines are important tools to study myeloma cell biology and are commonly used for preclinical screening and testing of new drugs. With few exceptions human myeloma cell lines are derived from NHRD patients, even though about half of the patients have HRD myeloma. Thus, there is a need for cell lines of HRD origin to enable more representative preclinical studies. Here, we present two novel myeloma cell lines, VOLIN and KJON. Both of them were derived from patients with HRD disease and shared the same genotype as their corresponding primary tumors. The cell lines' chromosomal content, genetic aberrations, gene expression, immunophenotype as well as some of their growth characteristics are described. Neither of the cell lines was found to harbor immunoglobulin heavy chain translocations. The VOLIN cell line was established from a bone marrow aspirate and KJON from peripheral blood. We propose that these unique cell lines may be used as tools to increase our understanding of myeloma cell biology. © 2016 Wiley Periodicals, Inc.


Assuntos
Linhagem Celular Tumoral , Mieloma Múltiplo/patologia , Aneuploidia , Diploide , Humanos , Imunofenotipagem , Mieloma Múltiplo/genética , Translocação Genética
8.
Blood ; 123(16): 2504-12, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24497533

RESUMO

Multiple myeloma (MM) is a B-cell malignancy driven in part by increasing copy number alterations (CNAs) during disease progression. Prognostically significant CNAs accumulate during clonal evolution and include gains of 1q21 and deletions of 17p, among others. Unfortunately, the mechanisms underlying the accumulation of CNAs and resulting subclonal heterogeneity in high-risk MM are poorly understood. To investigate the impact of jumping translocations of 1q12 (JT1q12) on receptor chromosomes (RCs) and subsequent clonal evolution, we analyzed specimens from 86 patients selected for unbalanced 1q12 aberrations by G-banding. Utilizing spectral karyotyping and locus-specific fluorescence in situ hybridization, we identified 10 patients with unexpected focal amplifications of an RC that subsequently translocated as part of a sequential JT1q12 to one or more additional RCs. Four patients exhibited amplification and translocation of 8q24 (MYC), 3 showed amplification of 16q11, and 1 each displayed amplification of 18q21.3 (BCL2), 18q23, or 4p16 (FGFR3). Unexpectedly, in 6 of 14 patients with the combination of the t(4;14) and deletion of 17p, we identified the loss of 17p as resulting from a JT1q12. Here, we provide evidence that the JT1q12 is a mechanism for the simultaneous gain of 1q21 and deletion of 17p in cytogenetically defined high-risk disease.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 1/genética , Mieloma Múltiplo/genética , Translocação Genética , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Análise Citogenética , Progressão da Doença , Humanos , Hibridização in Situ Fluorescente , Sequências Repetitivas Dispersas , Cariótipo , Mieloma Múltiplo/patologia , Risco
10.
Genes Chromosomes Cancer ; 54(11): 692-701, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26220195

RESUMO

The growth and survival factor hepatocyte growth factor (HGF) is expressed at high levels in multiple myeloma (MM) cells. We report here that elevated HGF transcription in MM was traced to DNA mutations in the promoter alleles of HGF. Sequence analysis revealed a previously undiscovered single-nucleotide polymorphism (SNP) and crucial single-nucleotide variants (SNVs) in the promoters of myeloma cells that produce large amounts of HGF. The allele-specific mutations functionally reassembled wild-type sequences into the motifs that affiliate with endogenous transcription factors NFKB (nuclear factor kappa-B), MZF1 (myeloid zinc finger 1), and NRF-2 (nuclear factor erythroid 2-related factor 2). In vitro, a mutant allele that gained novel NFKB-binding sites directly responded to transcriptional signaling induced by tumor necrosis factor alpha (TNFα) to promote high levels of luciferase reporter. Given the recent discovery by genome-wide sequencing (GWS) of numerous non-coding mutations in myeloma genomes, our data provide evidence that heterogeneous SNVs in the gene regulatory regions may frequently transform wild-type alleles into novel transcription factor binding properties to aberrantly interact with dysregulated transcriptional signals in MM and other cancer cells.


Assuntos
Alelos , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Mieloma Múltiplo/genética , Mutação , Fatores de Transcrição/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Mieloma Múltiplo/metabolismo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
11.
Genes Chromosomes Cancer ; 53(7): 549-57, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24638926

RESUMO

In studies of patients with multiple myeloma (MM), gene expression profiling (GEP) of myeloma cells demonstrates substantially higher expression of MMSET, FGFR3, CCND3, CCND1, MAF, and MAFB--the partner genes of 14q32 translocations--than GEP of plasma cells from healthy individuals. Interphase fluorescent in situ hybridization (FISH) was used to discriminate between chromosomal translocations involving different regions of the immunoglobulin heavy chain (IGH) genes at 14q32. With special probes designed for the constant region (IGHC) and the variable region (IGHV), IGH translocations were shown to be definite, nonrandom chromosomal fusions of IGHC with the loci of FGFR3, CCND1, CCND3, MAF, and MAFB genes; and IGHV with the locus of MMSET gene. When correlated with GEP results, the IGH translocations were found to drive expression levels of the partner genes to significantly higher levels (spikes) than copy-number variations. Hence, 42% of IGH translocations were identified among newly diagnosed MM patients (448/1,060). As GEP has become essential for assessing cancer risk, this novel approach is highly consistent with the cytogenetic features of the chromosomal translocations to effectively stratify molecular subgroups of MM on the basis of gene expression profiles of the IGH translocation partner genes in myeloma cells. © 2014 Wiley Periodicals, Inc.


Assuntos
Cromossomos Humanos Par 14/genética , Mieloma Múltiplo/genética , Translocação Genética , Perfilação da Expressão Gênica , Fusão Gênica , Humanos , Mieloma Múltiplo/metabolismo
12.
Blood ; 119(2): 503-12, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22072558

RESUMO

IL-6 signaling can be enhanced through transsignaling by the soluble IL-6 receptor (sIL-6r), allowing for the pleiotropic cytokine to affect cells it would not ordinarily have an effect on. Serum levels of sIL-6r can be used as an independent prognostic indicator and further stratify the GEP 70-gene low-risk group to identify an intermediate-risk group in multiple myeloma (MM). By analyzing more than 600 MM patients with ELISA, genotyping, and gene expression profiling tools, we show how the combination of 2 independent molecular genetic events is related to synergistic increases in sIL-6r levels. We also show that the rs2228145 minor allele is related to increased expression levels of an IL-6r splice variant that purportedly codes exclusively for a sIL-6r isoform. Together, the SNP rs2228145 minor allele C and amplification of chromosome 1q21 are significantly correlated to an increase in sIL-6r levels, which are associated with lower overall survival in 70-gene low-risk disease, and aid in identification of the intermediate-risk MM group.


Assuntos
Processamento Alternativo , Cromossomos Humanos Par 1/genética , Mieloma Múltiplo/sangue , Mieloma Múltiplo/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Interleucina-6/sangue , Receptores de Interleucina-6/genética , Estudos de Casos e Controles , DNA/genética , Genótipo , Humanos , Perda de Heterozigosidade , Mieloma Múltiplo/mortalidade , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Taxa de Sobrevida
13.
Blood ; 119(21): e148-50, 2012 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-22496154

RESUMO

Cytogenetic abnormalities are important clinical parameters in various types of cancer, including multiple myeloma. We developed a model to predict cytogenetic abnormalities in patients with multiple myeloma using gene expression profiling and validated it by different cytogenetic techniques. The model has an accuracy rate up to 0.89. These results provide proof of concept for the hypothesis that gene expression profiling is a superior genomic method for clinical molecular diagnosis and/or prognosis.


Assuntos
Aberrações Cromossômicas , Análise Citogenética/métodos , Perfilação da Expressão Gênica , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Biópsia por Agulha , Medula Óssea/metabolismo , Medula Óssea/patologia , Estudos de Casos e Controles , Hibridização Genômica Comparativa , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Análise em Microsséries/métodos , Modelos Estatísticos , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico , Sensibilidade e Especificidade
14.
Blood ; 118(13): 3512-24, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21628408

RESUMO

Gene expression profiling (GEP) of purified plasma cells 48 hours after thalidomide and dexamethasone test doses showed these agents' mechanisms of action and provided prognostic information for untreated myeloma patients on Total Therapy 2 (TT2). Bortezomib was added in Total Therapy 3 (TT3), and 48 hours after bortezomib GEP analysis identified 80 highly survival-discriminatory genes in a training set of 142 TT3A patients that were validated in 128 patients receiving TT3B. The 80-gene GEP model (GEP80) also distinguished outcomes when applied at baseline in both TT3 and TT2 protocols. In context of our validated 70-gene model (GEP70), the GEP80 model identified 9% of patients with a grave prognosis among those with GEP70-defined low-risk disease and 41% of patients with favorable prognosis among those with GEP70-defined high-risk disease. PMSD4 was 1 of 3 genes common to both models. Residing on chromosome 1q21, PSMD4 expression is highly sensitive to copy number. Both higher PSMD4 expression levels and higher 1q21 copy numbers affected clinical outcome adversely. GEP80 baseline-defined high risk, high lactate dehydrogenase, and low albumin were the only independent adverse variables surviving multivariate survival model. We are investigating whether second-generation proteasome inhibitors (eg, carfilzomib) can overcome resistance associated with high PSMD4 levels.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácidos Borônicos/farmacologia , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/genética , Pirazinas/farmacologia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/fisiologia , Ácidos Borônicos/administração & dosagem , Bortezomib , Cromossomos Humanos Par 1/genética , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Neoplásicos/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Farmacogenética , Prognóstico , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/fisiologia , Pirazinas/administração & dosagem , Proteínas de Ligação a RNA , Risco , Regulação para Cima/efeitos dos fármacos
16.
Blood Adv ; 6(3): 808-817, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34807986

RESUMO

Multiple myeloma (MM) patients frequently attain a bone marrow (BM) minimal residual disease (MRD) negativity status in response to treatment. We identified 568 patients who achieved BM MRD negativity following autologous stem cell transplantation (ASCT) and maintenance combination therapy with an immunomodulatory agent and a proteasome inhibitor. BM MRD was evaluated by next-generation flow cytometry (sensitivity of 10-5 cells) at 3- to 6-month intervals. With a median follow-up of 9.9 years from diagnosis (range, 0.4-30.9), 61% of patients maintained MRD negativity, whereas 39% experienced MRD conversion at a median of 6.3 years (range, 1.4-25). The highest risk of MRD conversion occurred within the first 5 years after treatment and was observed more often in patients with abnormal metaphase cytogenetic abnormalities (95% vs 84%; P = .001). MRD conversion was associated with a high risk of relapse and preceded it by a median of 1.0 years (range, 0-4.9). However, 27% of MRD conversion-positive patients had not yet experienced a clinical relapse, with a median follow-up of 9.3 years (range, 2.2-21.2). Landmark analyses using time from ASCT revealed patients with MRD conversion during the first 3 years had an inferior overall and progression-free survival compared with patients with sustained MRD negativity. MRD conversion correctly predicted relapse in 70%, demonstrating the utility of serial BM MRD assessment to complement standard laboratory and imaging to make informed salvage therapy decisions.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Medula Óssea , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/terapia , Recidiva Local de Neoplasia , Neoplasia Residual/diagnóstico , Transplante Autólogo , Resultado do Tratamento
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(2): 570-3, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21510429

RESUMO

A non-dispersed infrared (NDIR) methane gas sensors system based on infrared absorption spectrum theory was designed according to single light beam and double wavelengths technology. In the system, an infrared LED IRL715 serving as the light power, a absorptive gas cell with the function of dust-proof and damp-proof and a pyroelectric detector LIM-262 are composed of optical probe. Signal condition uses active filter circuit and differential amplifier, and binomial expression fits the relation curve between methane concentration and voltage, which realizes accurate detection of gas concentration. Experiment approved that the sensor system with good consistency and applicability can detect the range of 5% methane reliably and have 0.5% of the sensitivity, possessing the conditions for industrial applications initially.

18.
Bone ; 146: 115876, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33556629

RESUMO

Multiple myeloma (MM) patients frequently present with extensive osteolytic bone lesions. However, the impact of myeloma treatment on focal lytic lesion remineralization has not been extensively studied. In this study, the effect of anti-myeloma treatment on the extent of bone remineralization was examined and potential mediators identified. Newly diagnosed MM patients enrolled in the Total Therapy 4 and 5 (TT4; n = 231, TT5; n = 64) protocols were longitudinally evaluated for changes in radiological parameters for a median of 6.1 years. Bone remineralization was defined as a sclerotic CT change within the lytic lesion and quantified as a percentage of remineralization, using the initial lesion size as a reference. Such changes were correlated to clinical and biochemical parameters, and the gene expression profile of bone marrow biopsy. Overall, remineralization occurred in 72% of patients (213/295). Of those patients that experienced remineralization, 36% (107/295) achieved at least 25% of bone remineralization. Patients with high-risk disease defined by gene expression profile signature (GEP70 ≥ 0.66) experienced significant remineralization compared to low-risk MM. Female patients were also more likely to experience bone remineralization and in a shorter median time (2.0 vs. 3.3 y). Factors such as serum alkaline phosphatase along with high levels of RUNX2 and SOX4 gene expression correlated with increasing extent of bone remineralization. This analysis demonstrated significant remineralization of lytic lesions in MM patients treated on TT clinical trials. While the underlying mechanism remains elusive these findings support the hypothesis that patient baseline bone-related factors play a fundamental role in the skeletal repair of bone lesions in MM that provide new opportunities for improving patient outcomes.


Assuntos
Doenças Ósseas , Mieloma Múltiplo , Arkansas , Medula Óssea , Osso e Ossos , Feminino , Humanos , Mieloma Múltiplo/tratamento farmacológico , Fatores de Transcrição SOXC
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(12): 3384-7, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21322245

RESUMO

This paper introduced the application of support vector machines (SVM) regression method based on kernel function optimized by the rough set in the infrared spectrum quantitative calculation. According to kernel function with the rough set classification's method, the spectrum data (characteristic wavelength section) is optimized. The kernel function leads support vector machines, and the SVM project the two-dimensional room to the multi-dimensional room, and calculate the concentration of every kind of gas in multi-component pollution gas. By using two kinds of typical spectrum data processing algorithm to make the contrast, the comparison of five kinds of gaseous mixture various proximate analysis is carried out, and when the spectrum separable rate is high, the predicted values of the three methods approach the normal value, and the average error is smaller than 0.13; but when the spectrum separable rate is low, the RS-SVM predicted value is more precise than the first two kinds. Experimental data show that the consequence is better when there are more testing types, and the precision and operation of this method is of more remarkable superiority.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 859-62, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20496727

RESUMO

In the static interferometer system, the variable refractive crystal LiNbO3 with electro-optic modulation was used in static Fourier transform interferometer, where both sides load phase opposite modulation signal separately so to raise the spectrum resolution in the same size of the instrument by the increment of optical path difference. According to the derivation of the optical path difference function with refraction modulation, the maximum optical path difference was calculated and the spectrum resolution was analyzed to be 16.7 times previous one when the refraction modulation was 0.030 in the same size of interferometer. The simulation result indicated that the refractive modulation would be reduced when the wavelength increased, and the value of optical path difference will be bigger when the chi' increased. In actual detection process, because spectral region 500-1 100 nm is relatively narrow, the spectrum distortion by the wavelength change is not big and may be compensated through the demarcation. This method can increase the optical path difference without mechanical scanning, and possibly raises spectrum resolution of the static interferometer.

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