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1.
Qual Life Res ; 29(9): 2563-2572, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32318940

ABSTRACT

PURPOSE: To develop and test the validity of a Patient-Reported Outcomes Measurement Information System (PROMIS®) short form for measuring physical function of geriatric rehabilitation patients. METHODS: Experts selected items from the Dutch-Flemish PROMIS v1.2 Physical Function (PROMIS-PF) item bank and proposed new items to develop the PROMIS-PF short form for geriatric rehabilitation (PROMIS-PF-GR). Patients evaluated its content validity. Structural validity was assessed by evaluating unidimensionality (confirmatory, exploratory, and bi-factor analyses [criterion: Omega H > 0.80 and ECV > 0.60]), local independence (criterion: residual correlation < 0.20) ,and monotonicity (criterion: Hi-coefficient ≥ 0.30). Measurement invariance was assessed by evaluating Differential Item Functioning (DIF) between geriatric rehabilitation patients and people from the general population using ordinal logistic regression. Internal consistency was assessed by calculating Cronbach's alpha (criterion: alpha ≥ 0.70). RESULTS: Experts selected 24 items from the PROMIS-PF item bank and proposed one new item which was not included in the short form. Patients considered the 24 items relevant and containing essential information. The PROMIS-PF-GR's psychometric properties were evaluated in 207 patients (mean age ± SD, 80.0 ± 8.3 year; 58% female). The 24 items were found to be sufficiently unidimensional (Omega H = 0.82, ECV = 0.70), locally independent (98.7% item pairs), and monotone (all ≥ 0.32). Five items were flagged for DIF, but their impact on the total score was negligible. Cronbach's alpha was 0.94. CONCLUSION: The PROMIS-PF-GR was developed from the PROMIS-PF and has good content validity, structural validity, measurement invariance, and internal consistency in Dutch geriatric rehabilitation patients. We recommend to confirm the content validity of the PROMIS-PF-GR in other countries.


Subject(s)
Patient Reported Outcome Measures , Psychometrics/methods , Quality of Life/psychology , Aged, 80 and over , Female , Humans , Male , Reproducibility of Results
2.
J Viral Hepat ; 23(2): 130-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26316075

ABSTRACT

Replicative senescence is a hallmark of chronic liver diseases including chronic hepatitis B virus (HBV) infection, whereas HBV-encoded oncoproteins HBx and preS2 have been found to overcome senescence. HBx possesses a C-terminal truncation mainly in hepatocellular carcinomas but also in noncancerous liver tissues. Here, by cell counting, BrdU incorporation, MTT proliferation assay, cell cycle analysis, SA-ßgal staining and Western blotting in primary and malignant cells, we investigated the effect of HBx C-terminal mutants on cellular senescence. HBx C-terminal mutants were found to trigger cellular senescence in primary MRC5 cells, and malignant liver cells Huh7, and SK-Hep1. In contrast, these mutants promoted the proliferation of HepG2 malignant liver cells. The pro-senescent effect of HBx relied on an increased p16(INK4a) and p21(Waf1/Cip1) expression, and a decreased phosphorylation of Rb. Together, these results suggest that the two main variants of HBx present in HBV-infected liver possess opposite effects on cellular senescence that depend on the phenotype of infected cells.


Subject(s)
Cell Proliferation/genetics , Cellular Senescence/genetics , Hepatitis B Surface Antigens/genetics , Liver Neoplasms/pathology , Protein Precursors/genetics , Trans-Activators/genetics , Cell Cycle , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p16/biosynthesis , Cyclin-Dependent Kinase Inhibitor p21/biosynthesis , Hep G2 Cells , Hepatitis B Surface Antigens/metabolism , Hepatitis B virus/genetics , Hepatitis B, Chronic/pathology , Hepatitis B, Chronic/virology , Hepatocytes/metabolism , Humans , Phenotype , Phosphorylation , Promoter Regions, Genetic/genetics , Protein Precursors/metabolism , Retinoblastoma Protein/metabolism , Trans-Activators/metabolism , Viral Regulatory and Accessory Proteins , beta-Galactosidase/metabolism
3.
Leukemia ; 30(4): 897-905, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26500139

ABSTRACT

After failure of erythropoiesis-stimulating agents (ESAs), lenalidomide (LEN) yields red blood cell (RBC) transfusion independence (TI) in 20-30% of lower-risk non-del5q myelodysplastic syndrome (MDS). Several observations suggest an additive effect of ESA and LEN in this situation. We performed a randomized phase III study in 131 RBC transfusion-dependent (TD, median transfusion requirement six RBC units per 8 weeks) lower-risk ESA-refractory non-del5q MDS. Patients received LEN alone, 10 mg per day, 21 days per 4 weeks (L arm) or LEN (same schedule) + erythropoietin (EPO) beta, 60,000 U per week (LE arm). In an intent-to-treat (ITT) analysis, erythroid response (HI-E, IWG 2006 criteria) after four treatment cycles (primary end point) was 23.1% (95% CI 13.5-35.2) in the L arm and 39.4% (95% CI 27.6-52.2) in the LE arm (P=0.044), while RBC-TI was reached in 13.8 and 24.2% of the patients in the L and LE arms, respectively (P=0.13). Median response duration was 18.1 and 15.1 months in the L and LE arms, respectively (P=0.47). Side effects were moderate and similar in the two arms. Low baseline serum EPO level and a G polymorphism of CRBN gene predicted HI-E. Combining LEN and EPO significantly improves erythroid response over LEN alone in lower-risk non-del5q MDS patients with anemia resistant to ESA.


Subject(s)
Blood Transfusion , Chromosome Deletion , Chromosomes, Human, Pair 5/genetics , Erythropoietin/therapeutic use , Myelodysplastic Syndromes/drug therapy , Thalidomide/analogs & derivatives , Aged , Anemia/prevention & control , Angiogenesis Inhibitors/therapeutic use , Drug Therapy, Combination , Female , Follow-Up Studies , Humans , Lenalidomide , Male , Middle Aged , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Neoplasm Staging , Prognosis , Prospective Studies , Risk Factors , Thalidomide/therapeutic use
4.
Leukemia ; 29(7): 1496-501, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25676424

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (HSCT) is considered the only a curative treatment in patients with higher risk myelodysplastic syndrome (MDS), although demethylating agents (DMA) have been reported to improve survival. The advantage of HSCT over other treatment comes from retrospective studies and the aim of the current study was to prospectively test this hypothesis, analyzing in particular patients from the pre-transplant period to avoid the selection bias of performing transplantation. This study was conducted to compare overall survival in MDS patients candidates to transplantation according to donor availability. The majority of patients (76%) received a treatment with DMA after registration, 69% had a human leukocyte antigen (HLA)-identical donor, 70% of whom were transplanted. Baseline patient and disease characteristics were similar according to donor availability. Four-year overall survival was significantly better in patients with an HLA matched donor (37%) compared to patients without donor (15%). There was also evidence that this overall survival advantage was because of transplantation. Mortality risk was decreased after transplantation but it became significant only after the second year post transplant, because of early transplant-related mortality. Our results appear to justify, in higher risk MDS, a transplantation approach in all potential candidates who have an HLA identical donor.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , HLA Antigens/immunology , Myelodysplastic Syndromes/immunology , Myelodysplastic Syndromes/therapy , Stem Cell Transplantation , Aged , Combined Modality Therapy , Female , Follow-Up Studies , Histocompatibility Testing , Humans , Male , Middle Aged , Myelodysplastic Syndromes/mortality , Myelodysplastic Syndromes/pathology , Neoplasm Staging , Prognosis , Prospective Studies , Retrospective Studies , Risk Factors , Survival Rate , Transplantation Conditioning , Transplantation, Homologous
5.
J Craniomaxillofac Surg ; 41(2): 92-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22789870

ABSTRACT

The aim of this study was to design mandibular ramal height growth curves for patients with HFM and compare those with the curves for a Dutch reference population. Two hundred fifty-one pre-operative orthopantomograms (OPTs) from 84 patients with unilateral HFM were used in conjunction with a control set of 2260 OPTs from 329 healthy individuals from the Nijmegen Growth Study (NGS) to determine mandibular ramal distances. For grades I/IIa and IIb/III, and for both sides, growth curves were constructed for mandibular ramal height with a linear curve-fitting procedure. This procedure revealed a significant difference between HFM patients and the NGS control group (p < 0.001); both in the mild and severe group mandibular ramal height differed significantly between the affected and non-affected side (p < 0.001). Growth was similar between HFM patients and the NGS control group. HFM patients therefore start with a smaller mandible and end with a smaller mandible, but experience growth similar to the Dutch normal population. These growth curves may aid the timing and determination of the combined surgical orthodontic treatment plan for HFM patients.


Subject(s)
Facial Asymmetry/physiopathology , Mandible/growth & development , Adolescent , Cephalometry/methods , Child , Child, Preschool , Facial Asymmetry/classification , Facial Asymmetry/pathology , Female , Goldenhar Syndrome/pathology , Goldenhar Syndrome/physiopathology , Humans , Image Processing, Computer-Assisted/methods , Male , Mandible/pathology , Models, Statistical , Netherlands , Patient Care Planning , Radiography, Panoramic/methods , Severity of Illness Index
6.
Br J Oral Maxillofac Surg ; 51(8): 902-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23201060

ABSTRACT

Hemifacial microsomia (HFM) is a complex three-dimensional congenital condition that is characterized by mandibular hypoplasia and unilateral or bilateral microtia; although, other facial structures may be affected. Little is known about craniofacial growth and morphology in patients with HFM; therefore, we examined 75 HFM patients by means of a cephalometric analysis in a longitudinal study on serial lateral cephalograms. We hypothesized that the growth of several facial structures on both sides of HFM patients would be different compared to Dutch controls. We determined patients with HFM had more retruded mandibles and maxillae and a more vertical morphology compared to the reference population. In addition, there was a more retruded and vertical pattern on the affected side compared to the unaffected side and in patients with a severe condition compared to those with a mild condition. 'Mild' HFM patients were more similar to the Dutch reference population than the 'severe' HFM patients. Individual HFM growth curves showed very high inter-variability, further strengthening the need for individualized treatment plans that consider all three dimensions and the severity of the condition.


Subject(s)
Cephalometry/methods , Facial Bones/pathology , Goldenhar Syndrome/pathology , Skull/pathology , Adolescent , Adult , Child , Child, Preschool , Facial Bones/growth & development , Female , Follow-Up Studies , Goldenhar Syndrome/physiopathology , Humans , Image Processing, Computer-Assisted/methods , Incisor/pathology , Longitudinal Studies , Male , Mandible/growth & development , Mandible/pathology , Maxilla/growth & development , Maxilla/pathology , Maxillofacial Development/physiology , Palate/growth & development , Palate/pathology , Retrognathia/pathology , Skull/growth & development , Vertical Dimension , Young Adult
7.
Cleft Palate Craniofac J ; 49(4): 472-6, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21851285

ABSTRACT

OBJECTIVE: Different three-dimensional stereophotogrammetry systems and analyzing methods exist that often use landmarks for comparison. Measurement errors in landmark or surface comparison are mostly within 1 mm, which seems clinically acceptable. The aim of this study was to validate a three-dimensional stereophotogrammetric best-fit method of assessing volumetric changes and to compare three devices. METHODS: The validation of the best-fit method was at first done on a life-size dummy head. Scans were made in the ideal position, as well as in four additional positions, and a scan was made in which a soft putty specimen was added to the dummy head. The comparison was executed with a best-fit method using triangulation. Student's t tests were used to detect statistically significant differences. Second, comparisons were made among scans of a white man in the ideal position and with volume changes added. RESULTS: The different positions tested for the dummy head showed no significant volume differences within each system or among systems. The differences found when adding a soft putty specimen fell into the same range as the differences between various positions. The differences within a live situation were 10 times greater compared with the dummy-head situation. CONCLUSIONS: In a dummy-head situation, the different systems gave similar results when tested with a best-fit method. However, in live situations the differences may become 10 times greater, possibly due to different facial expressions. These differences may become clinically relevant and, therefore, further research in volumetric changes is needed.


Subject(s)
Head/anatomy & histology , Imaging, Three-Dimensional , Photogrammetry/methods , Humans , Male , Patient Positioning , Phantoms, Imaging
8.
J Dent Res ; 89(12): 1368-72, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20739700

ABSTRACT

Hemifacial microsomia (HFM) is a congenital disorder marked by facial asymmetry. Whether facial asymmetry accounts for asymmetrical dental development is unknown. There are few data on dental development relative to mandibular development or severity of HFM, or on development over time. We hypothesized that when mandibular development was severely disturbed, local dental development was also affected. We compared dental development scores between affected and non-affected mandibular sides in patients with HFM (n = 84) and compared these data with those collected from Dutch control children (n = 451). Logistic functions were constructed for dental age over time for all four Pruzansky/Kaban types. The results showed a tendency toward delayed dental development in Pruzansky/Kaban types IIb and III at younger ages. The temporary delay of tooth formation in patients with severe forms of HFM and the distribution of agenic teeth suggest an interaction between mandibular and dental development.


Subject(s)
Facial Asymmetry/physiopathology , Odontogenesis/physiology , Adolescent , Adult , Age Determination by Teeth , Anodontia/physiopathology , Child , Child, Preschool , Facial Asymmetry/classification , Female , Goldenhar Syndrome/physiopathology , Humans , Male , Mandible/growth & development , Radiography, Panoramic
9.
Leukemia ; 23(11): 2081-9, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19587703

ABSTRACT

Telomerase activity, which has fundamental roles in development and carcinogenesis, strongly depends on the expression of human telomerase reverse transcriptase (hTERT), its catalytic subunit. In this report, we show that the basic helix-loop-helix factor, TAL1 (T-cell acute lymphoblastic leukemia 1), is a negative regulator of the hTERT promoter. Indeed, TAL1 overexpression leads to a decrease in hTERT mRNA abundance and hence to reduced telomerase activity. Conversely, suppression of TAL1 by RNA interference in Jurkat cells increases hTERT expression. Analysis by chromatin immunoprecipitation assays showed that TAL1 binds to the hTERT proximal promoter and recruits HDAC1. Considering the relationship recently established between TAL1 and the human T-cell leukemia virus type 1 (HTLV-1) Tax protein, which was confirmed in T lymphocyte clones derived from adult T-cell leukemia patients, we analyzed the effect of TAL1 with respect to the earlier characterized effects of Tax and HBZ (HTLV-1 basic leucine zipper) on hTERT expression. TAL1 was observed to reinforce the negative effect of Tax, whereas hTERT transactivation by the HBZ-JunD complex was repressed by TAL1 overexpression. Moreover, HBZ was found to induce proteasome-mediated degradation of TAL1. These observations support a model in which Tax and TAL1 by repressing hTERT would initially favor genomic instability, whereas expression of factors such as HBZ allows at a later stage an increase in hTERT production and consequently in telomerase activity.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Gene Expression Regulation, Leukemic/physiology , Leukemia, T-Cell/genetics , Proto-Oncogene Proteins/metabolism , Telomerase/genetics , Telomerase/metabolism , Basic-Leucine Zipper Transcription Factors/metabolism , Binding, Competitive/physiology , Gene Products, tax/genetics , Genomic Instability , HeLa Cells , Humans , Jurkat Cells , Leukemia, T-Cell/metabolism , Promoter Regions, Genetic/physiology , Retroviridae Proteins , Sp1 Transcription Factor/metabolism , T-Cell Acute Lymphocytic Leukemia Protein 1 , T-Lymphocytes/physiology , Viral Proteins/metabolism
10.
Eur J Orthod ; 27(3): 309-14, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15947233

ABSTRACT

Dental age was studied in a sample of 451 Dutch children (226 boys and 225 girls) according to the method of Demirjian. They were born between 1972 and 1993 and were between 3 and 17 years of age at the time a dental pantomogram (DPT) was obtained. All children were placed in the age group closest to their chronological age. All 451 DPTs were scored by one examiner. A subset of 52 DPTs was scored by a second examiner and the intra-class correlation coefficient (ICC) and Cohen's kappa were calculated. The ICC was 0.99 and Cohen's kappa 0.68. Boys and girls were analysed separately.A significant difference was found between chronological age and dental age. On average, the Dutch boys were 0.4 years and the girls 0.6 years ahead of the French-Canadian children analysed by Demirjian. Therefore, the French-Canadian standards were not considered suitable for Dutch children. New graphs for the Dutch population were constructed using a logistic curve with the equation Y = 100*{1/(1 + e(-alpha(x - x0)))} as a basis. The 90 per cent confidence interval was calculated. To determine whether the logistic curve was correct, a residual analysis was carried out and scatter plots of the differences were made. The explained variance was 93.9 per cent for the boys and 94.8 per cent for the girls. Both the residual analysis and the scatter plots indicated that the logistic curve was appropriate for use with Dutch children. In addition to the graphs, tables were produced which transfer the maturity scores calculated by the method of Demirjian into Dutch dental age.


Subject(s)
Age Determination by Teeth/methods , Adolescent , Aging/physiology , Child , Child, Preschool , Female , Humans , Logistic Models , Male , Netherlands , Radiography, Panoramic , Reproducibility of Results
11.
Leukemia ; 17(1): 26-38, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12529656

ABSTRACT

Most cancers and leukemias are preceded by a prolonged period of clinical latency during which cellular, chromosomal and molecular aberrations help move normal cell towards the malignant phenotype. The problem is that premalignant cells are usually indistinguishable from their normal counterparts, thereby ruling out the possibility to investigate the events that govern early leukemogenesis in vivo. Adult T cell leukemia/lymphoma (ATLL) is a T cell malignancy that occurs after a 40-60-year period of clinical latency in about 3-5% of HTLV-1-infected individuals. ATLL cells are monoclonally expanded and harbor an integrated provirus. A persistent oligo/polyclonal expansion of HTLV-1-bearing cells has been shown to precede ATLL, supporting the fact that in ATLL tumor cells arise from a clonally expanding non-malignant cell. It is possible to isolate infected, ie preleukemic, cells during the premalignant asymptomatic phase of the infection, thus providing an exceptional system to study the mechanisms underlying human cancers. Here we review some of the consequences of HTLV-1 on its host cell in vivo, at different stages of infection.


Subject(s)
HTLV-I Infections/complications , Human T-lymphotropic virus 1/genetics , Leukemia-Lymphoma, Adult T-Cell/etiology , Base Sequence , Cell Transformation, Neoplastic , Chromosome Aberrations , Clone Cells , HTLV-I Infections/pathology , Humans , Leukemia-Lymphoma, Adult T-Cell/pathology , Molecular Sequence Data , T-Lymphocytes/immunology , Viral Load , Virus Replication
12.
J Natl Cancer Inst ; 93(5): 367-77, 2001 Mar 07.
Article in English | MEDLINE | ID: mdl-11238698

ABSTRACT

BACKGROUND: Human T-cell leukemia virus type 1 (HTLV-1), the causative agent of adult T-cell leukemia/lymphoma, shows intrapatient genetic variability. Although HTLV-1 can replicate via the reverse transcription of virion RNA to a double-stranded DNA provirus (the conventional manner for retroviruses), its predominant mode of replication is via the clonal expansion (mitosis) of the infected cell. This expansion is achieved by the viral oncoprotein Tax, which keeps the infected CD4 T lymphocyte cycling. Because Tax also interferes with cellular DNA repair pathways, we investigated whether somatic mutations of the provirus that occur during the division of infected cells could account for HTLV-1 genetic variability. METHODS: An inverse polymerase chain reaction strategy was designed to distinguish somatic mutations from reverse transcription-associated substitutions. This strategy allows the proviral sequences to be isolated together with flanking cellular sequences. Using this method, we sequenced 208 HTLV-1 provirus 3' segments, together with their integration sites, belonging to 29 distinct circulating cellular clones from infected individuals. RESULTS: For 60% of the clones, 8%-80% of infected cells harbored a mutated HTLV-1 provirus, without evidence of reverse transcription-associated mutations. Mutations within flanking cellular sequences were also identified at a frequency of 2.8 x 10(-4) substitution per base pair. Some of these clones carried multiple discrete substitutions or deletions, indicating progressive accumulation of mutations during clonal expansion. The overall frequency of somatic mutations increased with the degree of proliferation of infected T cells. CONCLUSIONS: These data indicate that, in vivo, HTLV-1 variation results mainly from postintegration events that consist of somatic mutations of the proviral sequence occurring during clonal expansion. The finding of substitutions in flanking sequences suggests that somatic mutations occurring after integration, presumably coupled with selection, help move the cellular clones toward a transformed phenotype, of which adult T-cell leukemia/lymphoma is the end point.


Subject(s)
Cloning, Molecular , DNA, Viral/genetics , Human T-lymphotropic virus 1/genetics , Mutation , Proviruses/genetics , Terminal Repeat Sequences/genetics , Transcription, Genetic/genetics , Adult , Base Sequence , Blotting, Southern , DNA Primers , Humans , Molecular Sequence Data , Phosphopyruvate Hydratase/genetics , Polymerase Chain Reaction/methods , RNA, Viral/genetics
13.
J Virol ; 75(2): 1083-9, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11134325

ABSTRACT

After experimental infection of squirrel monkeys (Saimiri sciureus) with human T-cell leukemia virus type 1 (HTLV-1)-infected cells, the virus is transcribed only transiently in circulating blood, spleen, and lymph nodes. Stable disappearance of viral expression occurs at 2 to 3 weeks after inoculation. This coincides with the development of the anti-HTLV-1 immune response and persistent detection of the provirus in peripheral blood mononuclear cells (PBMCs). In this study, the HTLV-1 replication pattern was analyzed over time in PBMCs and various organs from two HTLV-1-infected squirrel monkeys. Real-time quantitative PCR confirmed that PBMCs and lymphoid organs constitute the major reservoirs for HTLV-1. The PCR amplification of HTLV-1 flanking sequences from PBMCs evidenced a pattern of clonal expansion of infected cells identical to that observed in humans. Dissemination of the virus in body compartments appeared to result from cellular transport of the integrated provirus. The circulating proviral burden increased as a function of time in one animal studied over a period of 4 years. The high proviral loads observed in the last samples resulted from the accumulation of infected cells via the extensive proliferation of a restricted number of persistent clones on a background of polyclonally expanded HTLV-1-positive cells. Therefore, HTLV-1 primary infection in squirrel monkeys is a two-step process involving a transient phase of reverse transcription followed by persistent multiplication of infected cells. This suggests that the choice of the target for blocking HTLV-1 replication might depend on the stage of infection.


Subject(s)
HTLV-I Infections/virology , Human T-lymphotropic virus 1/physiology , Virus Replication , Animals , Cell Line , Clone Cells , DNA, Viral/analysis , HTLV-I Infections/physiopathology , Human T-lymphotropic virus 1/genetics , Human T-lymphotropic virus 1/isolation & purification , Humans , Leukocytes, Mononuclear/virology , Lymphocyte Activation , Lymphoid Tissue/virology , Male , Proviruses/genetics , Saimiri , Viral Load
14.
AIDS Res Hum Retroviruses ; 16(16): 1653-9, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11080806

ABSTRACT

Sequencing integration sites from >/=200 proviruses isolated from infected individuals revealed that HTLV-1 integration is not random at the level of the nucleotide sequence. The virus was found to integrate in A/T-rich regions with a weak consensus sequence at positions within and without the hexameric repeat generated during integration. These features were not associated with a preference for integration near active regions or repeat elements of the host chromosomes. However, about 6% of HTLV-1 proviruses were found to be integrated into transcription units, suggesting that in some cells, HTLV-1 integration may alter gene expression in vivo. Therefore, the target choice in vivo seems to be determined by local features rather than by the accessibility of specific regions. This led us subsequently to analyze the role of the DNA structure in HTLV-1 integration in vitro. Double-strand HTLV-1 or HIV-1 3' LTR extremities were used as substrates for in vitro strand transfer reactions using highly purified HTLV-1 and HIV-1 integrases (INs) expressed in Escherichia coli, and two synthetic naked 50-bp double-strand DNA molecules harboring different structures were used as targets. A fluorometric quantitative analysis of integration products was designed to assess the reaction efficiency for both target sequences. As suggested for HTLV-1 in vivo (present results), and, as previously described for other retroviruses in vitro, the structure of the target was found to greatly influence the site and the efficiency of integration. Both HIV-1 and HTLV-1 INs underwent the same target structural constraint, i.e., a strong preference for curved DNA. Altogether these results indicate that if most or all the regions of the genome appear to be accessible to HTLV-1 integration, local DNA curvature seems to confer a kinetic advantage for both in vitro and in vivo HTLV-1 integration.


Subject(s)
HTLV-I Infections/virology , Human T-lymphotropic virus 1/genetics , Virus Integration/genetics , Base Sequence , DNA/genetics , HIV Integrase/genetics , HIV Integrase/metabolism , HIV-1/genetics , Human T-lymphotropic virus 1/pathogenicity , Human T-lymphotropic virus 1/physiology , Humans , Integrases/genetics , Integrases/metabolism , Terminal Repeat Sequences/genetics
15.
Oncogene ; 19(43): 4954-60, 2000 Oct 12.
Article in English | MEDLINE | ID: mdl-11042682

ABSTRACT

Adult T cell leukemia (ATLL) develops in 3 - 5% of HTLV-1 carriers after a long period of latency during which a persistent polyclonal expansion of HTLV-1 infected lymphocytes is observed in all individuals. This incubation period is significantly shortened in HTLV-1 carrier with Strongyloides stercoralis (Ss) infection, suggesting that Ss could be a cofactor of ATLL. As an increased T cell proliferation at the asymptomatic stage of HTLV-1 infection could increase the risk of malignant transformation, the effect of Ss infection on infected T lymphocytes was assessed in vivo in HTLV-1 asymptomatic carriers. After real-time quantitative PCR, the mean circulating HTLV-1 proviral load was more than five times higher in HTLV-1 carriers with strongyloidiasis than in HTLV-1+ individuals without Ss infection (P<0.009). This increased proviral load was found to result from the extensive proliferation of a restricted number of infected clones, i.e. from oligoclonal expansion, as evidenced by the semiquantitative amplification of HTLV-1 flanking sequences. The positive effect of Ss on clonal expansion was reversible under effective treatment of strongyloidiasis in one patient with parasitological cure whereas no significant modification of the HTLV-1 replication pattern was observed in an additional case with strongyloidiasis treatment failure. Therefore, Ss stimulates the oligoclonal proliferation of HTLV-1 infected cells in HTLV-1 asymptomatic carriers in vivo. This is thought to account for the shortened period of latency observed in ATLL patients with strongyloidiasis. Oncogene (2000) 19, 4954 - 4960


Subject(s)
Human T-lymphotropic virus 1/physiology , Proviruses/physiology , Strongyloides stercoralis , Strongyloidiasis/virology , T-Lymphocytes/virology , Viral Load , Virus Replication , Adult , Aged , Aged, 80 and over , Animals , Antinematodal Agents/therapeutic use , Carrier State/blood , Carrier State/virology , Child , Clone Cells , Female , Human T-lymphotropic virus 1/genetics , Humans , Lymphocyte Activation , Male , Middle Aged , Polymerase Chain Reaction , Proviruses/genetics , Strongyloidiasis/blood , Strongyloidiasis/drug therapy , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Thiabendazole/therapeutic use
16.
Br J Haematol ; 110(3): 591-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10997969

ABSTRACT

In the myelodysplastic syndromes (MDS), P-glycoprotein (P-gp) expression is clinically associated with drug resistance, whereas the clinical significance of multidrug resistance-associated protein (MRP1) is uncertain. Bone marrow from 56 patients with MDS, including six with refractory anaemia (RA)/RA with ringed sideroblasts (RARS), 23 cases of RA with excess blasts/in transformation (RAEB/T), four patients with chronic myelomonocytic leukaemia (CMML) and 23 cases of MDS having progressed to acute myeloid leukaemia (MDS-AML), were studied. MRP1 expression was investigated by immunocytochemistry (ICC) and by flow cytometry using MRPm6 monoclonal antibody. The efflux test using calcein-AM (CAM) +/- probenecid to evaluate MRP1 activity was performed in ten of the 56 patients. Twenty-eight of the 56 cases (50%) expressed MRP1. MRP1 expression was more frequent in MDS-AML than in MDS (70% vs. 36%). The efflux test using CAM was positive in three out of the ten patients tested. The results were in agreement with expression of MRP1 in six cases, and were discordant in four cases (1 MRP-/CAM+, 3 MRP+/CAM-). No correlation was observed between MRP1 expression and P-gp, lung resistance-associated protein (LRP) or CD34 expression, although there was a trend for more frequent MRP1 expression in P-gp-positive cases in MDS-AML (P = 0.08). Ten of the 26 patients treated with intensive chemotherapy achieved complete remission including six out of 16 MRP1+ and four out of ten MRP1- cases (P = NS). In conclusion, MRP1 expression was correlated with disease stage in MDS in our study. As for P-gp, discordant expression/function of MRP1 could be found in some cases, suggesting the existence of non-functional transport proteins in MDS. MRP1 expression did not seem to be a prognostic factor in MDS in our experience.


Subject(s)
ATP-Binding Cassette Transporters/analysis , Myelodysplastic Syndromes/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/analysis , Adult , Animals , Antigens, CD34/analysis , Cell Line , Chi-Square Distribution , Chromosome Aberrations/metabolism , Chromosome Disorders , Flow Cytometry , Humans , Immunohistochemistry/methods , Leukemia, Myeloid/drug therapy , Leukemia, Myeloid/metabolism , Middle Aged , Multidrug Resistance-Associated Proteins , Myelodysplastic Syndromes/drug therapy , Neoplasm Proteins/analysis , Treatment Outcome , Vault Ribonucleoprotein Particles
17.
J Infect Dis ; 182(4): 1044-50, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10979898

ABSTRACT

In the spinal cord of patients with human T cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), infiltrating CD4(+) lymphocytes seem to be the major reservoir for the virus. Little, however, is known about the mechanisms by which HTLV-1 crosses the blood-brain barrier. An oligoclonal proliferation of HTLV-1-infected CD4 lymphoid T cells is present in the peripheral blood of all HTLV-1-infected individuals. Here, such oligoclonal distribution of HTLV-1-infected cells is evidenced in the cerebrospinal fluid (CSF) derived from 5 patients with HAM/TSP. Furthermore, clonal populations of HTLV-1-infected lymphocytes sharing the same HTLV-1 proviral flanking sequences (i.e. , integration sites in the cellular DNA), and thus derived from a single HTLV-1-infected progenitor, were found, for a given patient, in both the CSF and the peripheral blood. These data demonstrate that HTLV-1 crosses the blood-brain barrier by migration of HTLV-1-infected lymphocytes in vivo.


Subject(s)
Blood-Brain Barrier , Human T-lymphotropic virus 1/physiology , Lymphocytes/virology , Paraparesis, Tropical Spastic/cerebrospinal fluid , Virus Integration , Adult , Base Sequence , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/virology , DNA Primers , Female , Human T-lymphotropic virus 1/genetics , Human T-lymphotropic virus 1/isolation & purification , Humans , Male , Middle Aged , Paraparesis, Tropical Spastic/blood , Paraparesis, Tropical Spastic/immunology , Polymerase Chain Reaction , Proviruses/genetics , Proviruses/physiology
18.
Blood ; 96(3): 852-8, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-10910896

ABSTRACT

Using Cox models, we established a new prognostic system based on simple clinical parameters in a training series of 232 patients whose diagnoses were made before 1989. Adverse prognostic factors for survival (P <.01) were age 65 years or older, male gender, albumin level lower than 40 g/L, hemoglobin level lower than 12 g/dL, platelet count less than 150 x 10(9)/L, white blood cell count less than 4 x 10(9)/L, high number of cytopenias, and hepatomegaly. Taking age (age 65 years or older, 1 point; younger than 65 years, 0 points), albumin (less than 40 g/L, 1 point; 40 g/L or more, 0 points), and total number of cytopenias (no cytopenia, 0 points; 1 cytopenia, 1 point; 2 or 3 cytopenias, 2 points) into account, we separated the 232 patients into 3 groups with low (score 0 or 1), intermediate (score 2), or high (score 3 or 4) risk, associated with 5-year survival rates at 87%, 62%, and 25%, respectively (P <.0001). Only the presence of 2 or 3 cytopenias was an independent prognostic factor among patients younger than 65 years (P <.0001). Albumin level lower than 40 g/L and the presence of 1 or more cytopenia defined a prognostic system for patients 65 years and older. Patients at low risk, intermediate risk, and high risk had 5-year survival rates at 92%, 63%, and 27%, respectively (P <.0001). The 3 prognostic systems separated the 167 patients of a test series in groups with significantly different survival rates. The overall scoring system retained a significant prognostic value in 86 additional patients treated between 1990 and 1996. We conclude that the combination of age, albumin level, and blood cell counts might help to select patients with Waldenström macroglobulinemia for treatment and to evaluate therapeutic results.


Subject(s)
Prognosis , Waldenstrom Macroglobulinemia/physiopathology , Adult , Aged , Female , Humans , Male , Middle Aged , Statistics as Topic , Survival Analysis
19.
J Clin Oncol ; 18(5): 963-71, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10694545

ABSTRACT

PURPOSE: To identify predictive factors of survival, relapse, and transplantation-related mortality (TRM) among patients with therapy-related myelodysplastic syndrome (t-MDS) or acute leukemia (t-AML) who underwent allogeneic bone marrow transplantation (BMT). PATIENTS AND METHODS: From 1980 to 1998, 70 patients underwent allogeneic BMT for t-MDS (n = 31) or t-AML (n = 39) after prior cytotoxic exposure. Thirty-three patients had received induction-type chemotherapy before BMT. At the time of transplantation, there were 24 patients in complete remission (CR) and 46 with active disease. RESULTS: With a median follow-up of 7.9 years (range, 1.1 to 18.8 years) after BMT, 16 patients are alive, whereas 19 died of relapse, 34 of TRM, and one of relapse of the primary disease. The estimated 2-year overall survival, event-free survival, relapse, and TRM rates were 30% (95% confidence interval [CI], 19% to 40%), 28% (95% CI, 18% to 39%), 42% (95% CI, 26% to 57%), and 49% (95% CI, 36% to 62%), respectively. In multivariable analysis, age greater than 37 years, male sex, positive recipient cytomegalovirus (CMV) serology, absence of CR at BMT, and intensive schedules used for conditioning were associated with poor outcome. CONCLUSION: BMT is an effective treatment for patients with t-MDS or t-AML who have responsive disease and, in particular, who have no poor-risk cytogenetic features. The poor results of the other patients, especially those with active disease at BMT, emphasize the need to delineate indications and perform prospective protocols.


Subject(s)
Bone Marrow Transplantation , Leukemia, Megakaryoblastic, Acute/therapy , Myelodysplastic Syndromes/therapy , Neoplasms, Second Primary/therapy , Transplantation, Homologous , Adolescent , Adult , Female , France , Humans , Leukemia, Megakaryoblastic, Acute/etiology , Leukemia, Megakaryoblastic, Acute/mortality , Male , Middle Aged , Multivariate Analysis , Myelodysplastic Syndromes/etiology , Myelodysplastic Syndromes/mortality , Neoplasms, Second Primary/etiology , Neoplasms, Second Primary/mortality , Outcome Assessment, Health Care , Survival Analysis
20.
J Virol ; 74(5): 2305-12, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10666261

ABSTRACT

Human pathogenic retroviruses do not have common loci of integration. However, many factors, such as chromatin structure, transcriptional activity, DNA-protein interaction, CpG methylation, and nucleotide composition of the target sequence, may influence integration site selection. These features have been investigated by in vitro integration reactions or by infection of cell lines with recombinant retroviruses. Less is known about target choice for integration in vivo. The present study was conducted in order to assess the characteristics of cellular sequences targeted for human T-cell leukemia virus type 1 (HTLV-1) integration in vivo. Sequencing integration sites from >/=200 proviruses (19 kb of sequence) isolated from 29 infected individuals revealed that HTLV-1 integration is not random at the level of the nucleotide sequence. The virus was found to integrate in A/T-rich regions with a weak consensus sequence at positions within and without of the hexameric repeat generated during integration. These features were not associated with a preference for integration near active regions or repeat elements of the host chromosomes. Most or all of the regions of the genome appear to be accessible to HTLV-1 integration. As with integration in vitro, integration specificity in vivo seems to be determined by local features rather than by the accessibility of specific regions.


Subject(s)
HTLV-I Infections/virology , Human T-lymphotropic virus 1/genetics , Proviruses/genetics , Virus Integration , AT Rich Sequence , DNA/chemistry , DNA, Viral/genetics , HTLV-I Infections/genetics , Humans , Leukemia, T-Cell/genetics , Leukemia, T-Cell/virology , Sequence Homology, Nucleic Acid
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