13q14 deletions are not primary events in B-cell chronic lymphocytic leukemia: a study of 100 patients using fluorescence in situ hybridization

Fluorescence in situ hybridization with a chromosome 12-specific alpha-centromeric probe and a 13q14 yeast artificial chromosome probe was performed on interphase cells from 100 patients with B-cell chronic lymphocytic leukemia. Thirty-one patients exhibited a 13q14 deletion. No correlation was found between 13q14 deletions and clinical stage, sex, or morphology. Sixteen patients had trisomy 12, including 6 (of 12) with an atypical morphology. Trisomy 12 and 13q14 abnormalities were detected concomitantly in three patients only. The analysis of patients with deletions clearly showed that in five cases a significant number of cells retained two signals with the yeast artificial chromosome probe, indicating a genetic heterogeneity among the leukemic population. Our data confirm that the 13q14 deletion is a frequent event, indicate that the concomitant occurrence of 13q14 deletion and trisomy 12 is rare but possible, and show that both abnormalities are secondary events in B-cell chronic lymphocytic leukemia.     

Rb1 gene expression in B-cell lymphocytic leukaemia cases with deletion in the 13q14 region

Recent studies have been carried out to delineate further the role of the Rb1 gene in B-cell chronic lymphocytic leukaemia (B-CLL). The suggested role of the Rb1 gene in this disease was based on cytogenetic data. CLL patients (40 in toto) were examined using cytogenetic and molecular biological methods. R-banding analysis of metaphase chromosomes revealed aberrations in only seven cases containing either the Rb1 gene or a chromosome 13 monosomy. No evident differences were found by RT-PCR analysis of Rb1 gene expression. The amounts of the RT-PCR products obtained appeared to be approximately equal in all cases, and was independent of the clinical stage, immunophenotypes and LPS or TPA stimulation.     

Expressed sequences as candidates for a novel tumor suppressor gene at band 13q14 in B-cell chronic lymphocytic leukemia and mantle cell lymphoma

Deletions affecting the interval between the RB1 gene and marker D13S25 at band 13q14 are the most frequent genetic abnormalities of B-cell chronic lymphocytic leukemia (B-CLL) and indicate the presence of a novel tumor suppressor gene in this region. In the current study, a high resolution physical map of fragments spanning one megabasepair (Mb) of genomic DNA at the critical 13q14 segment was constructed. To define the minimal region of loss within the RB1 and D13S25 interval, we screened 322 B-CLLs for deletions at either of the two loci. Thirty mantle cell lymphomas (MCLs) were included in the analysis because we observed a 13q14 deletion pattern similar to B-CLL in this disease. The incidence of 13q14 deletions was 51% in B-CLL and 70% in MCL, respectively. No frequent loss of the BRCA2 gene at band 13q12 was found. Detailed deletion mapping at band 13q14 with probes from the RB1-D13S25 interval lead to the identification of a critical deletion region 400 kb in size. Within this region two segments were most frequently affected, one at D13S272 120 kb in size and another 240 kb distal of D13S272 80 kb in size. From these two segments expressed sequences were identified as candidates for the putative 13q14 tumor suppressor gene involved in the pathogenesis of B-CLL and MCL.     

Isolation of a novel human homologue of the gene coding for echinoderm microtubule-associated protein (EMAP) from the Usher syndrome type 1a locus at 14q32

Routine follow-up visits and vault cytology following treatment for endometrial carcinoma generates a considerable workload and takes up valuable resources. A review is needed to evaluate the usefulness of this practice. Eighty six patients treated and follow-up from January, 1987 to July, 1994 were reviewed. The standard follow-up protocol consisted of physical assessment and vault cytology every 1 to 2 months for the first 2 years, every 3 months for the third year and every 6 months thereafter for at least 5 years. Recurrences were defined as histologically proven disease after a 3-month disease free interval. Fourteen patients (17%) developed recurrences. Two of the 14 patients (14%) had local recurrences in the pelvis. Only 3 of these recurrences were detected during routine follow-up. Vault cytology was negative in all patients with recurrences even when the recurrence occurred locally in the pelvis. Traditional surveillance protocols were ineffective in the detection of recurrences. Vault cytology was particularly ineffective. It was calculated that 1 recurrence was detected for every 606 visits. In this age of budgetary constraints, alternative follow-up protocols should be explored.     

Acute myelogenous leukemia with monosomy 7, inv(3) (q21q26), involving activated EVI 1 gene occurring after a complete remission of lymphoblastic lymphoma: a case report

A 42-year-old female with a mediastinal tumor and massive pleural effusion ws admitted to our hospital in June 1993. Biopsy revealed lymphoblastic lymphoma. She had no evidence of distant metastasis except pleural effusion. Bone marrow examination revealed a normal karyotype (46, XY). The patient had been progression-free for more than 1 year after achieving complete remission by induction, consolidation and maintenance therapy according to the standard chemotherapy and involved-field radiation for lymphoblastic lymphoma. From May 1996 progressive leukopenia and thrombocytopenia developed. The diagnosis of refractory anemia with excess of blasts (RAEB) was made. Subsequently, in November 1996, she developed acute myelogenous leukemia (AML), M4 type by FAB classification. The karyotype of MDS and AML clones involved inversion (3) (q21q26) and monosomy 7. The EVI 1 gene was examined and was proved to be rearranged and activated. This may be the first case among the therapy-related cases of MDS/AML reported whose karyotypes were followed and in which the mRNA expression of EVI 1 gene involved was directly proved in the leukemogenesis process of chemotherapy-induced secondary MDS and AML.     

A der(22)t(9;22)(p13;q11) in bone marrow cells of a patient with multiple myeloma: a variant of the t(9;14)(p13;q32) associated with a subset of lymphoplasmacytoid lymphoma

An adult cattle egret (Bubulcus ibis) caught in Kobe of Hyogo Prefecture, Japan, in December 1995 died of a severe infection associated with the trematode parasite Pegosomum sp. At necropsy, 22 trematode parasites were found in the lumen of the bile duct, and the duct wall was markedly thickened. Histopathologically, severe cholangitis and cholecystitis were observed in close association with the parasites in the bile duct. Severe Pegosomum sp. infection may be one of the factors contributing to the mortality of wild cattle egrets. This is the first reported case of the genus Pegosomum infection in wild birds of Japan.     

Plasminogen activator inhibitor-1 secretion of endothelial cells increases fibrinolytic resistance of an in vitro fibrin clot: evidence for a key role of endothelial cells in thrombolytic resistance

Time-dependent thrombolytic resistance is a critical problem in thrombolytic therapy for acute myocardial infarction. Platelets have been regarded as the main source of plasminogen activator inhibitor-1 (PAI-1) found in occlusive platelet-rich clots. However, endothelial cells are also known to influence the fibrinolytic capacity of blood vessels, but their ability to actively mediate time-dependent thrombolytic resistance has not been fully established. We will show that, in vitro, tumor necrosis factor-alpha-stimulated endothelial cells secrete large amounts of PAI-1 over a period of hours, which then binds to fibrin and protects the clot from tissue plasminogen activator-induced fibrinolysis. In vivo, endothelial cells covering atherosclerotic plaques are influenced by cytokines synthesized by plaque cells. Therefore, we propose that continuous activation of endothelial cells in atherosclerotic blood vessels, followed by elevated PAI-1 secretion and storage of active PAI-1 in the fibrin matrix, leads to clot stabilization. This scenario makes endothelial cells a major factor in time-dependent thrombolytic resistance.     

Early-onset Alzheimer''s disease due to mutations of the presenilin-1 gene on chromosome 14: a 7-year follow-up of a patient with a mutation at codon 139

In recent years, several factors have altered the spectrum of respiratory infections and their likelihood of response to empiric treatment. Altered microbial resistance has led to the possible need for specific etiologic diagnosis in some hospital-acquired infections in the normal host. In the immune-compromised host, the spectrum of atypical presentations and unusual organisms limits the clinician's ability to choose effective empiric therapies. In the normal host, bronchoscopic diagnosis seems to be most useful in the groups with severe community-acquired pneumonia or poor response to therapy for community-acquired pneumonia. The group of patients with ventilator-associated pneumonia has been well-researched and the bronchoscopic techniques tend to show increased sensitivity over other diagnostic means, but this has not been proven to alter morbidity, mortality, or cost effectiveness. The immune-compromised host is commonly infected by organisms not easily diagnosed by other means and is thus unable to be treated empirically. Bronchoscopic diagnostic techniques play a larger and more clearly delineated role in these populations, including the patient populations with solid organ transplants, bone marrow transplants, and AIDS.     

Two acute monocytic leukemia (AML-M5a) cell lines (MOLM-13 and MOLM-14) with interclonal phenotypic heterogeneity showing MLL-AF9 fusion resulting from an occult chromosome insertion, ins(11;9)(q23;p22p23)

We describe two new human leukemia cell lines, MOLM-13 and MOLM-14, established from the peripheral blood of a patient at relapse of acute monocytic leukemia, FAB M5a, which had evolved from myelodysplastic syndrome (MDS). Both cell lines express monocyte-specific esterase (MSE) and MLL-AF9 fusion mRNA. Gene fusion is associated with a minute chromosomal insertion, ins(11;9)(q23;p22p23). MOLM-13 and MOLM-14 are the first cell lines with, and represent the third reported case of, MLL gene rearrangement arising via chromosomal insertion. Both cell lines carry trisomy 8 which was also present during the MDS phase, as well as the most frequent trisomies associated with t(9;11), ie, +6, +13, +19 variously present in different subclones. Despite having these features in common, differences in antigen expression were noted between the two cell lines: that of MOLM-13 being CD34+, CD13-, CD14-, CD15+, CD33+; whereas MOLM-14 was CD4+, CD13+, CD14+, CD15+, CD33+. Differentiation to macrophage-like morphology could be induced in both cell lines after stimulation with INF-gamma alone, or in combination with TNF-alpha, which treatment also induced or upregulated, expression of certain myelomonocyte-associated antigens, including CD13, CD14, CD15, CD64, CD65 and CD87. Together, these data confirm that both cell lines are likely to be novel in vitro models for studying monocytic differentiation and leukemogenesis.     

Colocalization of glucagon-like peptide-1 (GLP-1) receptors, glucose transporter GLUT-2, and glucokinase mRNAs in rat hypothalamic cells: evidence for a role of GLP-1 receptor agonists as an inhibitory signal for food and water intake

This study was designed to determine the possible role of brain glucagon-like peptide-1 (GLP-1) receptors in feeding behavior. In situ hybridization showed colocalization of the mRNAs for GLP-1 receptors, glucokinase, and GLUT-2 in the third ventricle wall and adjacent arcuate nucleus, median eminence, and supraoptic nucleus. These brain areas are considered to contain glucose-sensitive neurons mediating feeding behavior. Because GLP-1 receptors, GLUT-2, and glucokinase are proteins involved in the multistep process of glucose sensing in pancreatic beta cells, the colocalization of specific GLP-1 receptors and glucose sensing-related proteins in hypothalamic neurons supports a role of this peptide in the hypothalamic regulation of macronutrient and water intake. This hypothesis was confirmed by analyzing the effects of both systemic and central administration of GLP-1 receptor ligands. Acute or subchronic intraperitoneal administration of GLP-1 (7-36) amide did not modify food and water intake, although a dose-dependent loss of body weight gain was observed 24 h after acute administration of the higher dose of the peptide. By contrast, the intracerebroventricular (i.c.v.) administration of GLP-1 (7-36) amide produced a biphasic effect on food intake characterized by an increase in the amount of food intake after acute i.c.v. delivery of 100 ng of the peptide. There was a marked reduction of food ingestion with the 1,000 and 2,000 ng doses of the peptide, which also produced a significant decrease of water intake. These effects seemed to be specific because i.c.v. administration of GLP-1 (1-37), a peptide with lower biological activity than GLP-1 (7-36) amide, did not change feeding behavior in food-deprived animals. Exendin-4, when given by i.c.v. administration in a broad range of doses (0.2, 1, 5, 25, 100, and 500 ng), proved to be a potent agonist of GLP-1 (7-36) amide. It decreased, in a dose-dependent manner, both food and water intake, starting at the dose of 25 ng per injection. Pretreatment with an i.c.v. dose of a GLP-1 receptor antagonist [exendin (9-39); 2,500 ng] reversed the inhibitory effects of GLP-1 (7-36) amide (1,000 ng dose) and exendin-4 (25 ng dose) on food and water ingestion. These findings suggest that GLP-1 (7-36) amide may modulate both food and drink intake in the rat through a central mechanism.