Calcein assay for multidrug resistance reliably predicts therapy response and survival rate in acute myeloid leukaemia

In this study, we evaluated the suitability of the calcein assay as a routine clinical laboratory method for the identification of multidrug-resistant phenotype in acute leukaemia. This study presents the results of the calcein tests obtained in two large haematological centres in Hungary. Assays were performed with blast cells of 93 de novo acute leukaemia patients, including 65 patients with acute myeloid leukaemia (AML). Results were expressed as multidrug resistance activity factor (MAF) values. AML patients were divided into responders and non-responders and MAF values were calculated for each group. In both centres, responder patients displayed significantly lower MAF values than non-responders (P = 0.0045 and P = 0.0454). Cut-off values were established between the MAFR + SEM and MAFNR - SEM values. On the basis of these cut-off levels, multidrug resistance (MDR) negativity showed a 72% predictive value for the response to chemotherapy, whereas MDR positivity was found to have an average predictive value of 69% for therapy failure. MDR activity was a prognostic factor for survival rate and the test was suitable for detecting patients at relapse. The calcein assay can be used as a quantitative, standardized, inexpensive screening test in a routine clinical laboratory setting. The assay detects both P-glycoprotein and multidrug resistance-associated protein activities, and identifies AML patients with unfavourable therapy responses.

The response of balanitis xerotica obliterans to local steroid application compared with placebo in children

PURPOSE

We evaluated the clinical effectiveness of topical steroid application for balanitis xerotica obliterans in children and analyzed the association of any clinical response with histological findings.

MATERIALS AND METHODS

Our double-blind, placebo controlled, randomized study included 40 boys in whom balanitis xerotica obliterans was diagnosed clinically by cicatricial phimosis. The severity of phimosis was graded into 4 groups. Patients were randomized to receive the topical application of 0.05% mometasone furoate or placebo. After 5 weeks phimosis severity was reevaluated and all patients underwent circumcision. Surgical specimens were histologically typed as an early, intermediate or late form of balanitis xerotica obliterans.

RESULTS

Seven patients were withdrawn from the study. In the steroid group 7 boys had clinical improvement and 10 had no change. Histological study showed an early, intermediate and late form of balanitis xerotica obliterans in 5, 5 and 7 cases, respectively. Of cases with clinical improvement 5 were the early and 2 the intermediate type. In the placebo group 5 cases worsened clinically and 11 did not change. Histological evaluation revealed an early, intermediate and late form of balanitis xerotica obliterans in 3, 7 and 6 boys, respectively. Of the 5 cases with histological worsening, disease was the early, intermediate and late type in 2, 2 and 1, respectively.

CONCLUSIONS

Applying a potent topical steroid affects improvement in balanitis xerotica obliterans in the histologically early and intermediate stages of disease, and may inhibit further worsening in the late stage.

Hepatitis viruses and hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is among the most frequent malignancies worldwide. Hepatitis viruses, such as the hepatitis B virus (HBV) and hepatitis C virus (HCV) are undoubtedly listed in the etiology of HCC. Studies show that, in the near future, viral hepatitis will carry increasing weight in the etiology of HCC. This review briefly discusses the known carcinogenic effects of HBV and HCV in the light of experimental and human studies. The data show that viral proteins may directly interfere with gene products responsible for cell proliferation and cell growth. Many other signal transduction cascades may be affected as well. Direct integration of HBV viral sequences into the host genome increases the genomic instability. The genomic imbalance allows the development and survival of malignant clones bearing defected genomic information. HBV and HCV infection induces indirect and direct mechanisms through cellular damage, increased regeneration and cell proliferation, therefore enhancing the development of HCC.

Corticotropin-releasing hormone mRNA levels in response to chronic mild stress rise in male but not in female rats while tyrosine hydroxylase mRNA levels decrease in both sexes

Corticotropin-releasing hormone (CRH) and catecholamines are suggested to play a significant role in the pathophysiology of depression. In the present study we investigated gene expression of CRH in the hypothalamic paraventricular nucleus (PVN) and tyrosine hydroxylase (TH) in the locus coeruleus (LC) in an experimental model of depression. A chronic mild stress model was applied in rats of both genders for a three-week period. Anhedonic behaviour, a typical sign of depression-like state, was measured by a sucrose preference test. The chronic mild stress induced a decrease in sucrose preference in both genders. The body weight gain was reduced in males only. The total activity in the open field test was unchanged, however, male rats exposed to chronic mild stress showed enhanced locomotor activity during the first minute of the session, suggesting increased anxiety. Basal plasma corticosterone levels, thymus and adrenal weights measured on the third day after cessation of the stress regimen, were not affected by the stress procedure. Evaluation of CRH mRNA levels in the PVN by in situ hybridisation revealed a significant rise in response to chronic mild stress in males. In females, the basal CRH mRNA levels were higher compared to those in males, but the stress-induced rise was absent. Chronic mild stress resulted in a decrease in TH mRNA levels in the LC. These data demonstrate that chronic mild stress model of depression induces a specific stress response with a reduction of TH gene expression in the LC and clear gender differences in gain of body weight, anxiety-like behaviour, and CRH mRNA levels in the PVN.

Daily profiles of arginine vasopressin mRNA in the suprachiasmatic, supraoptic and paraventricular nuclei of the rat hypothalamus under various photoperiods

Daily rhythm of arginine vasopressin (AVP) mRNA levels in the suprachiasmatic nucleus (SCN) of rats maintained under a short, LD 8:16 photoperiod differed from that of rats maintained under a long, LD 16:8 photoperiod: under the short photoperiod the morning AVP rise occurred significantly later than under the long one. Daily profiles of AVP mRNA in the supraoptic and paraventricular nuclei were not rhythmic and AVP mRNA levels under LD 8:16 did not differ from those under LD 16:8. The data indicate that photoperiod affects selectively the clock driven AVP gene expression in the SCN.

Molecular cloning and functional characterization of inhibitor-sensitive (mENT1) and inhibitor-resistant (mENT2) equilibrative nucleoside transporters from mouse brain

Mammalian cells express at least two subtypes of equilibrative nucleoside transporters, i.e. ENT1 and ENT2, which can be distinguished functionally by their sensitivity and resistance respectively to inhibition by nitrobenzylthioinosine. The ENT1 transporters exhibit distinctive species differences in their sensitivities to inhibition by dipyridamole, dilazep and draflazine (human>mouse>rat). A comparison of the ENT1 structures in the three species would facilitate the identification of the regions involved in the actions of these cardioprotective agents. We now report the molecular cloning and functional expression of the murine (m)ENT1 and mENT2 transporters. mENT1 and mENT2 encode proteins containing 458 and 456 residues respectively, with a predicted 11-transmembrane-domain topology. mENT1 has 88% and 78% amino acid identity with rat ENT1 and human ENT1 respectively; mENT2 is more highly conserved, with 94% and 88% identity with rat ENT2 and human ENT2 respectively. We have also isolated two additional distinct cDNAs that encode proteins similar to mENT1; these probably represent distinct mENT1 isoforms or alternative splicing products. One cDNA encodes a protein with two additional amino acids (designated mENT1b) that adds a potential protein kinase CK2 phosphorylation site in the central intracellular loop of the transporter, and is similar, in this regard, to the human and rat ENT1 orthologues. The other cDNA has a 5'-untranslated region sequence that is distinct from that of full-length mENT1. Microinjection of mENT1, mENT1b or mENT2 cRNA into Xenopus oocytes resulted in enhanced uptake of [(3)H]uridine by the oocytes relative to that seen in water-injected controls. mENT1-mediated, but not mENT2-mediated, [(3)H]uridine uptake was inhibited by nitrobenzylthioinosine and dilazep. Dipyridamole inhibited both mENT1 and mENT2, but was significantly more effective against mENT1. Adenosine inhibited both systems with a similar potency, as did a range of other purine and pyrimidine nucleosides. These results are compatible with the known characteristics of the native mENT1 and mENT2 transporters.

Role of alpha-1-adrenergic receptors in the regulation of corticotropin-releasing hormone mRNA in the paraventricular nucleus of the hypothalamus during stress

1. The role of alpha1-adrenergic receptors on CRH mRNA levels in the PVN was studied in control and stressed rats receiving i.c.v. injections of the alpha1-adrenergic agonist, methoxamine, or the alpha1- antagonist, prazosin. 2. Plasma ACTH increased significantly 60 min and 4 hr after a single injection of methoxamine (100 microg, i.c.v.). No desensitization of this response was observed after repeated injections every 6 hr for 24 hr. Concomitantly, POMC mRNA in the anterior pituitary increased by 25% at 4 hr after a single injection and by 96% after repeated injections. 3. CRH mRNA levels in the PVN increased by 131% after repeated injections for 24 hr, but were unchanged 4 hr after a single injection. Central alpha-adrenergic blockade with prazosin did not prevent the increases in CRH mRNA following 4 hr of acute stress, but significantly reduced the increases observed 24 hr after an i.c.v. injection of 75 microg of colchicine or after repeated i.p. hypertonic saline injections every 8 hr. 4. These studies demonstrate that while alpha1-adrenergic receptors contribute to longterm increases of CRH mRNA levels in the PVN during prolonged stress, other factors are likely to be involved in the stimulation of CRH mRNA following acute stimulation.

Myelofibrosis in systemic lupus erythematosus

In this study we present a case of coexisting systemic lupus erythematosus (SLE) and myelofibrosis. Literature review supports the fact that the two diseases rarely occur together in the same patient. The young female patient studied was admitted with pancytopenia and a clinical picture which met the criteria of SLE. Histological examination of the bone marrow biopsy revealed severe myelofibrosis with hypocellularity of the myeloid cell lines. Treatment with immunosuppressive and colony stimulating factor led to slow but complete regeneration of the bone marrow and subsequently to an improved haematological status, and the patient was spared bone marrow transplantation.

[Fluorescence in situ hybridization in the diagnosis and follow-up of chronic myelogenous leukemia]

Chronic myelogenous leukaemia is a clonal myeloproliferative stem cell disease. Its cytogenetical hallmark is the Philadelphia chromosome (Ph) or the BCR/ABL fusion gene. Their identification is important both in the diagnosis and the follow-up of the disease. In our department we have investigated the BCR/ABL gene arrangement in 21 patients with fluorescence in situ hybridization. The aim of the analysis in freshly suspected patients without any previous therapy was to confirm diagnosis and mapping the ratio of Philadelphia positive cells. In contrast to the 95-100% Ph-positivity of mononuclear cells by classical cytogenetical examinations we found BCR/ABL gene arrangement only in various but always lower proportions. Therefore the latter examination gives a better representation of residual normal hemopoesis. Out of 9 patients who had received interferon treatment for at least 6 months, 4 gave a major, 4 a minor cytogenetical answer and in 1 case there was no cytogenetical response. Seven patients reached a complete and 2 a partial hematological remission. Among 5 other patients receiving interferon treatment, in 2 cases with double Ph-positivity we found a rapid progression. The data of 3 patients had to be excluded from the evaluation due to the so far short following time.

DNA bending induced by DNA (cytosine-5) methyltransferases

DNA bending induced by six DNA (cytosine-5) methyltransferases was studied using circular permutation gel mobility shift assay. The following bend angles were obtained: M.BSP:RI (GG(m5)CC), 46-50 degrees; M.HAE:III (GG(m5)CC), 40-43 degrees; M.SIN:I (GGW(m5)CC), 34-37 degrees; M.SAU:96I (GGN(m5)CC), 52-57 degrees; M.HPA:II (C(m5)CGG), 30 degrees; and M.HHA:I (G(m5)CGC), 13 degrees. M. HAE:III was also tested with fragments carrying a methylated binding site, and it was found to induce a 32 degrees bend. A phase-sensitive gel mobility shift assay, using a set of DNA fragments with a sequence-directed bend and a single methyltransferase binding site, indicated that M.HAE:III and M. BSP:RI bend DNA toward the minor groove. The DNA curvature induced by M.HAE:III contrasts with the lack of DNA bend observed for a covalent M.HAE:III-DNA complex in an earlier X-ray study. Our results and data from other laboratories show a correlation between the bending properties and the recognition specificities of (cytosine-5) methyltransferases: enzymes recognizing a cytosine 3' to the target cytosine tend to induce greater bends than enzymes with guanine in this position. We suggest that the observed differences indicate different mechanisms employed by (cytosine-5) methyltransferases to stabilize the helix after the target base has flipped out.

Alterations of P53 and RB genes and the evolution of the accelerated phase of chronic myeloid leukemia

Using the single-strand conformation polymorphism and heteroduplex analyses, the P53 and RB genes were analyzed in cell samples from twenty-eight patients with chronic myeloid leukemia (CML) both at diagnosis and at the onset of accelerated phase (AP) of the disease. No alterations of the P53 or RB genes were found in any of the chronic phase (CP) samples. Structural abnormalities of the P53 gene were observed in ten of twenty-eight AP samples within exons 4, 5, 7 and 9. Of the ten cases of AP disease with altered P53 genes, five patients also suffered from the deletion of the other allele. Alterations of the RB gene could be detected in six AP samples, and aberrant band patterns were found in the analysis of exons 2, 3, 4, 6, 7, 13, 14, 17, 21 and 26. Among the six AP samples with structural abnormalities of the RB gene, two showed the loss of the other allele. It is of note that alterations of both P53 and RB genes were observed in two AP samples. Our data strongly suggest that abnormalities of the P53 and RB genes and acceleration of CML are linked events in some cases of AP.

[7-aza analogs of quinazolino-carboline alkaloids. Synthesis, structure, characterization]

The synthesis, structure and characterization of 8-substituted-7-azarutaecarpines (2) is described. These compounds were prepared by Fischer indolization of 3-amino-2-(1-phenylhydrazonoethyl)-4(3H)-quinazolin-one (5), followed by cyclocondensation with a series of aliphatic or aromatic aldehydes and formic acid or a Vilsmeyer-Haack reagent. The stereochemistry of compounds (2) was investigated by 1H nmr spectroscopy. It was found that the 8-substituents assume a quasi-axial position on the flattened boat conformation of ring C of (2), with the exception of ortho substituted phenyl groups, which occupy quasi-equatorial position. Semiempirical MO calculations support these conformational preferences.

[Detection of minimal residual diseases in B-cell tumors using PCR specific for the immunoglobulin heavy chain gene]

In B-cell non-Hodgkin's lymphomas (NHL), clonal rearrangement of the immunoglobulin heavy chain (IgH) gene provides a useful marker for the detection of minimal residual disease (MRD) after treatment. To explore clinical usefulness of polymerase chain reaction (PCR) analysis of clonal IgH gene rearrangement in the detection of MRD a follow up study of 10 patients with B-cell NHL have been performed. At the time of diagnosis, tumor DNAs were PCR-amplified using sense primer specific for the heavy chain variable region (VH) and antisense primer specific for the heavy chain joining region (JH) of the IgH gene. The clonal rearrangement of IgH gene detected by PCR was used as clonal marker to determine MRD after treatment. In three cases, where clinical remission was not achieved, clonal IgH gene rearrangement was detected after the treatment. In seven cases, clinical remission was achieved after induction therapy but the PCR analysis revealed clonal IgH gene rearrangement in three of the cases. In all of the three cases, where MRD was detected by PCR, clinical relapse developed after 7-28 months of the therapy. In all cases that have relapsed, the IgH gene rearrangement was identical at the time of initial diagnosis and at the relapse. This study demonstrates that PCR analysis of clonal IgH gene rearrangement is a useful method to monitor and detect MRD before clinical relapse.

Investigation on the formation of the hormone reception mechanism

The formation of the hormone receptor mechanism is part of the embryonic development. The perinatal age seems to be critical for the maturation of this system, i.e. the development of the proper hormone selectivity, the number of the receptors, their sensitivity to the adequate hormone. Our team tried to get a closer view on this developmental period examining different parameters in different model systems. We were able to show that during the maturation of the hormonal system similar responses could be elicited by the later specific hormones or by the non-specific ones but structurally similar compounds. Also it became evident that one single hormonal treatment, applied during in the perinatal age, could influence the responsiveness to hormones of the adult animals.

Xanthine stone in the urinary bladder of a male child

Urinary tract calculi composed primarily of xanthine are rate both in adults and children. We describe the clinical presentation and management of a 3.5-year-old boy with hereditary xanthinuria (an autosomal recessive disorder of purine metabolism) and primary bladder calculus formed from xanthine. To our knowledge this case demonstrates a previously undescribed form of xanthinuria in childhood. Xanthine stones, although rare, should be considered in the diagnosis of urolithiasis.

Increased leukocyte-platelet adhesion in chronic myeloproliferative disorders with high platelet counts

The heterophilic adhesions between monocytes and platelets may result in the modification of both platelet and monocyte function. This mutual modification includes a greater activation of platelets with increased production of PDGF and other metabolites as well as an enhanced tissue factor expression of monocytes with greater activity in the circulation. The heterophilic aggregation has been well documented during extracorporal circulation, haemodialysis and in diabetic retinopathy. Here we provide evidence that there is significant increase of monocyte-platelet aggregates in disorders associated with high platelet counts, such as chronic myeloproliferative disorders. The presence of these heterophilic aggregates may contribute to the vascular complications observed frequently in polycythaemia vera and essential thrombocythaemia.

Acute increase in blood flow to the rat bladder subsequent to partial bladder outlet obstruction

Partial obstruction of the rat bladder outlet initiates a multi-step process during which the bladder progressively loses its functional ability. The first step in this progression is bladder hypertrophy; the organ dramatically increases in size and weight to compensate for the effects of obstruction. Unoperated female rats, age-matched, sham-obstructed rats, and rats that received a partial bladder outlet obstruction were studied. During the first 24 hours after partial bladder outlet obstruction, relative bladder blood flow was measured using a fluorescent microsphere infusion technique and laser Doppler imaging. Nitric oxide synthase (NOS) activities of control and obstructed rat bladder tissues were determined using an enzymatic assay that measures the conversion of (3)H-L-arginine to (3)H-L-citrulline. Using the microsphere infusion technique, a significant increase in blood flow to the obstructed rat bladder was observed during the first 24 hours after partial bladder outlet obstruction. Relative bladder blood flow increased approximately sixfold at 4 and 6 hours post-obstruction and remained elevated through 24 hours of obstruction. Sham operations (evaluated after 6 hours after surgery) resulted in a minor increase in blood flow that did not reach statistical significance. Relative blood flow to the spleen, measured in the same rats, was not significantly changed. Laser Doppler measurements also identified a significant increase in rat bladder blood flow after outlet obstruction and showed that increased blood flow could be detected as early as 1 hour post-obstruction. Interestingly, despite the significant differences in bladder blood flow between control and early post-obstructed rat bladders, NOS activities of control and obstructed rat bladders were comparable. The increase in bladder blood flow precedes the urothelial, fibroblast and smooth muscle cell hyperplasia, and the smooth muscle hypertrophy that occurs after obstruction. We propose that, in response to surgical induction of partial outlet obstruction, acute up-regulation of bladder blood flow may be an initiating factor for subsequent bladder cell proliferation and smooth muscle hypertrophy. Neurourol. Urodynam. 19:195-208, 2000.

[Preliminary results of the study of the relationship between cricopharyngeal incoordination and gastroesophageal reflux in infants]

The authors summarise the results of barium swallow examinations and polysomnographic studies performed on 66 infants (41 male, 25 female), average age 63 days (26-130 days). Oesophageal pH monitoring was also performed as part of the polysomnographic examination. The results showed the highest incidence of cricopharyngeal incoordination (CPI) in the 6-10 weeks age group. Although they failed to demonstrate statistical significance between CPI and increased gastro-oesophageal reflux, they consider the two entities to be most probably related. No relation was found between CPI and abnormal polysomnographic results. They give an overview of the literature on the pathology of the cricopharyngeal muscle and with regard to the lack of uniformity in the terminology of previous publications, they present their use of terminology.

Multicentric Castleman disease and systemic lupus erythematosus phenotype in a boy with Klinefelter syndrome: long-term disease stabilization with interferon therapy

An 11-year-old boy with Klinefelter syndrome had Castleman disease (CD) of plasma cell type develop. Nonregulated antibody production mimicked systemic lupus erythematosus (SLE). Hepatitis C virus (HCV) infection caused significant disease worsening. The patient was treated with a daily dosage of 2 million units/m2 of IFN-alpha. Dramatic clinical improvement and decreasing autoimmune phenomenon were observed. HCV RNA were cleared. Hypergammaglobulinemia did not change. The boy has been living for 8 years with his disease. Plasma cell type CD can mimic collagenosis. Disease worsening is caused by HCV, though it can be reversed with IFN-alpha. Klinefelter syndrome may be a genetic susceptibility factor for CD in some cases.

The effect of intravesical mitomycin C on the recurrence of superficial (Ta-T1) bladder cancer. A Hungarian Multicenter Study

We evaluated the prophylactic efficacy of instillations of intravesical mitomycin C in 57 patients with primary superficial bladder cancer in a multicenter clinical trial. After complete transurethral resection of Ta-T1 G1-G2 transitional cell bladder carcinomas, patients were treated with mitomycin 40 mg/50 ml saline of 15 instillations for 12 months. Most of the complications were mild and transient but two patients dropped out of the trial because of moderate side effects. Fifty-one patients were evaluable. We observed tumour recurrences in six patients (11.8%) during a median follow-up of 44.5 months. The recurrences were treated by transurethral resection. There was no muscle invasive progression in the recurrences. Our investigations confirm the effectiveness of mitomycin C in the treatment of patients with superficial bladder cancer.

Use of a platelet filter test in patients with thrombocytosis

In the differential diagnosis of primary and secondary thrombocytosis platelet function tests may play an important role. We examined the applicability of a platelet filter test (shear-dependent platelet aggregation) as a tool, to differentiate primary thrombocytosis (cases with myeloproliferative disorders) from secondary (reactive) thrombocytosis. The test was carried out in 53 patients suffering from myeloproliferative disorders associated with primary thrombocytosis and in 21 patients with other diseases complicated by secondary thrombocytosis. Using citrate as anticoagulant, the sensitivity of the O'Brien's test proved to be 77.1%, and its specificity 94.4%. Using heparin as anticoagulant the sensitivity and specificity of the test were found to be also reliably high. Based on these studies we suggest the use of the O'Brien's filterometer as a screening test in the differential diagnosis in patients with elevated platelet count. In the case of normal results, the causes of reactive thrombocytosis should be clarified first, while with abnormal results, haematological examination of the patients should be performed.