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91.
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93.
F. Gilsanz J. A. Garcia Vela J. A. Vargas J. Ibañez F. Oña J. López M. Roggendorf 《Annals of hematology》1995,71(4):181-183
Persistent infection by parvovirus B19 associated with pure red cell aplasia (PRCA) has been documented in immunocompromised patients. Bone marrow failure is associated with conditions in which immune surveillance is impaired, and in these instances occult parvovirus infection may be suspected. In this study we have assessed by serological and molecular methods whether parvovirus B19 infection may be a more frequent cause of PRCA than hitherto suspected and whether it may be present in the absence of a typical bone marrow picture. Six patients with PRCA — two with isolated PRCA and no apparent underlying disease, two with a lymphoproliferative disease, one with thymoma, and one with chronic myelomonocytic leukemia — have been studied. Four of the six patients had overt PCRA and were clearly immunocompromised. Parvovirus B19 was not detected in any of the six patients by PCR analysis and serology investigating the presence of IgM or IgG antibodies. Although parvovirus B19 infection needs to be ruled out in PRCA it represents only one, and probably not the most frequent, etiological factor of PRCA. 相似文献
94.
García M Vargas JA Castejón R Navas E Durantez A 《Tuberculosis (Edinburgh, Scotland)》2002,82(1):37-41
We assessed by flow-cytometry the Th1/Th2 profiles in peripheral blood lymphocytes (PBL) from patients with active tuberculosis (TB), before and after antituberculous therapy, and from healthy tuberculin-positive and -negative reactors. PBL from patients showed a reduced potential for Th1-cytokine (notably IFN- gamma) production after culture with a policlonal stimulus. When these PBL from patients were cultured with a M. tuberculosis (MTB)-specific antigen such as PPD (10 microg/ml), there was no detectable production of Th1 cytokines. Only the Th2 cytokine IL10 was detected in PBL from patients but not from controls. However, at the site of the tuberculosis disease, T lymphocytes from bronchoalveolar lavage, after culture with PPD, produced IFN- gamma. After completion of tuberculosis therapy, PBL did not produce IL10. These data indicate that the immunosuppression observed in PBL during active tuberculosis infection may be related to IL10 production, and to the compartmentalization of the antigen-Th1 response to sites of active MTB infection. 相似文献
95.
Cerveró C Escribano L San Miguel JF Díaz-Agustín B Bravo P Villarrubia J García-Sanz R Velasco JL Herrera P Vargas M González M Navarro JL Orfao A 《American journal of hematology》1999,60(3):191-195
Bcl-2 protein plays a major role in the prevention of programmed cell death of differentiating cells. In the present study, the expression of cytoplasmic bcl-2 by human Bone Marrow Mast Cells (BMMC) from both normal and pathological bone marrow samples was examined. A total of 35 subjects corresponding to 9 healthy volunteers, 8 cases of adult indolent systemic mast cell disease (SMCD), 4 cases of pediatric mastocytosis (PM), 11 cases of hematological malignancies (HM), 2 cases of reactive bone marrow, and 1 case of mast cell leukemia (MCL) were analyzed. The expression of bcl-2 was studied using quantitative three-color flow cytometry. We also studied the molecular configuration of the bcl-2 gene and other relatives by Southern blot and polymerase chain reaction (PCR) in the MCL case. Bcl-2 expression was detected in BMMC from all samples analyzed. No significant differences on the expression of bcl-2 were detected between BMMC from healthy subjects and patients with SMCD, PM, HM, and reactive bone marrow. By contrast, bcl-2 protein was overexpressed in BMMC from MCL patient without gene rearrangement. Our results show that bcl-2 protein was constitutively expressed by BMMC. BMMC from MCL display overexpression of bcl-2, which could not be related to molecular rearrangements involving the bcl-2 gene. The expression of this protein by mature MC may play a role in the prevention of MC apoptosis and thus help to explain the long survival of these cells. The overexpression of bcl-2 by BMMC in MCL may help to explain their resistance to chemotherapy-induced apoptosis. 相似文献
96.
Torchinsky MY Gomez R Rao J Vargas A Mercante DE Chalew SA 《Journal of diabetes and its complications》2004,18(4):220-223
Although higher levels of hemoglobin A1c (HbA1c) and blood pressure precede the development of nephropathy in Type 1 diabetes (T1DM), the relationship between glycemic control and cardiovascular factors early in the course of diabetes is not clear. We conducted a retrospective study from clinic data for a 1-year period in 148 children with T1DM aged 12.5+/-4.4 years who had average diabetes duration of 4.5+/-3.3 years. The influence of HbA1c and reported insulin dose on blood pressure and heart rate were analyzed in multivariate linear regression models, statistically adjusted for the effect of race, sex, age, body mass index, and duration of diabetes. There was a significant positive correlation of mean HbA1c with mean diastolic blood pressure (P<.025) and mean heart rate (P<.0004). Higher diastolic blood pressure and heart rate were associated with higher HbA1c. Increased insulin doses were also associated with increased diastolic blood pressure (P<.009) and heart rate (P<.013). Insulin dose and HbA1c were also significantly correlated (P<.001). There was no correlation between mean HbA1c and mean systolic blood pressure. Increased levels of HbA1c and insulin dose are associated with increased diastolic blood pressure and heart rate. Although within the normal range, early increases of diastolic blood pressure and heart may indicate early cardiovascular changes in response to diabetes and potentially contribute to a greater proclivity for later development of nephropathy. 相似文献
97.
p16INK4A and p15INK4B gene deletions in primary leukemias 总被引:4,自引:0,他引:4
Haidar MA; Cao XB; Manshouri T; Chan LL; Glassman A; Kantarjian HM; Keating MJ; Beran MS; Albitar M 《Blood》1995,86(1):311-315
The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses. The ALL cases showed a relatively high frequency of homozygous deletions (22%, 6 of 27) at the p16INK4A gene locus. Interestingly, of the six cases with p16INK4A homozygous deletions, only three showed homozygous deletions at the p15INK4B gene. In 81 CLL patients, we detected one homozygous and five heterozygous deletions at both the p16INK4A and p15INK4B genes and two heterozygous deletions at the p16INK4A gene alone. Deletion of these two genes in AML cases is relatively low (9%). We did not detect deletions in any of the MDS, HCL, and CML cases examined. Sequence analyses of p16INK4A gene of six CLL cases with heterozygous deletion at this locus showed a 27-bp deletion at the splice acceptor site of intron 1 in one case and changes in the coding sequence in three other cases. The data presented in this report showed that (1) p16INK4A and p15INK4B genes are preferentially deleted homozygously in ALL and heterozygously in CLL cases with frequent mutation in the second allele, and (2) p16INK4A gene appears to be more frequently deleted than p15INK4B gene. 相似文献
98.
This review will discuss conventional and advanced magnetic resonance (MRI) imaging techniques used to study the spine and spinal cord according to the anatomical structures and clinical indications. Clinical challenges that neuroradiologists may face are also discussed, such as the “when” and “where” concerning the use of each technique, and in which pathology or clinical scenario each technique is useful. Finally, some “tips and tricks” to overcome the challenges are provided with clinical examples. 相似文献
99.
N Mohebbi R Vargas‐Poussou SCA Hegemann B Schuknecht AD Kistler RP Wüthrich CA Wagner 《Clinical genetics》2013,83(3):274-278
Mohebbi N, Vargas‐Poussou R, Hegemann SCA, Schuknecht B, Kistler AD, Wüthrich RP, Wagner CA. Homozygous and compound heterozygous mutations in the ATP6V1B1 gene in patients with renal tubular acidosis and sensorineural hearing loss. Distal renal tubular acidosis (dRTA) is characterized by the inability to excrete acid in the renal collecting ducts resulting in inappropriately alkaline urine and hyperchloremic (normal anion gap) metabolic acidosis in the context of a normal (or near‐normal) glomerular filtration rate. Inborn dRTA can be due to autosomal dominant or recessive gene defects. Clinical symptoms vary from mild acidosis, incidental detection of kidney stones or renal tract calcification to severe findings such as failure to thrive, severe metabolic acidosis, and nephrocalcinosis. The majority of patients with recessive dRTA present with sensorineural hearing loss (SNHL). Few cases with abnormal widening of the vestibular aqueduct have been described with dRTA. Mutations in three different genes have been identified, namely SLC4A1, ATP6V1B1, and ATP6V0A4. Patients with mutations in the ATP6V1B1 proton pump subunit develop dRTA and in most of the cases sensorineural hearing loss early in childhood. We present two patients from two different and non‐consanguineous families with dRTA and SNHL. Direct sequencing of the ATP6V1B1 gene revealed that one patient harbors two homozygous mutations and the other one is a compound heterozygous. To our knowledge, this is the first case in the literature describing homozygosity in the same dRTA gene on both alleles. 相似文献
100.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231