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Biomedical subjects

L Pajor

Publications and source records attributed to L Pajor.

At least 19 recordsLinked to original sources

Philadelphia chromosome and/or bcr-abl mRNA-positive primary thrombocytosis: morphometric evidence for the transition from essential thrombocythaemia to chronic myeloid leukaemia type of myeloproliferation.

AIMS: The incidence, bone marrow morphology and genetic features of bcr+ essential thrombocythaemia were investigated. METHODS AND RESULTS: Sixty-four consecutive patients meeting the criteria of essential thrombocythaemia have been investigated for bcr-abl rearrangement and chimera mRNA expression. Reverse transcriptase-polymerase chain reaction indicated bcr-abl expression in six patients, in two of whom large fraction of the blood and bone marrow cells proved to be positive for Philadelphia chromosome (Ph) by fluorescent in-situ hybridization (FISH) and conventional cytogenetic analysis. In the remaining four patients FISH analysis could not detect Ph+ cells among the blood cells, but in one of these four patients conventional cytogenetic analysis indicated a very small fraction (2%) of Ph+ mitoses in the bone marrow (bcr+ essential thrombocythaemia patients). In three of these four patients, X-chromosome-linked clonality assay showed that the disease is of uncommitted stem cell origin. During an average of 57 month long follow-up no transformation to chronic myeloid leukaemia type of disease or acceleration/blastic crisis could be observed in the four bcr+ essential thrombocythaemia patients. They did not differ significantly from typical essential thrombocythaemia patients in quantitative indices of bone marrow cellularity or the size of megakaryocytes. In these two parameters as well as in the total nucleolus organizer region area per nucleus, however, significant differences could be detected between these four as well as typical chronic myeloid leukaemia patients. Statistical analysis of the morphometric data obtained from all six Ph+ and bcr+ essential thrombocythaemia patients combined indicated a shift of the bone marrow morphology towards the chronic myeloid leukaemia type of myeloproliferation. CONCLUSIONS: These investigations indicate that bcr+ essential thrombocythaemia is infrequent among essential thrombocythaemia patients, and this condition resembles essential thrombocythaemia more than chronic myeloid leukaemia. Various expansions of the Ph+ clone appear to lead to either essential thrombocythaemia or, rather, chronic myeloid leukaemia type of myeloproliferation; however, data in the present study do not indicate that bcr+ essential thrombocythaemia would be a form fruste variant of chronic myeloid leukaemia.

Adult↗

Frequent occurrence of low grade cases among metastatic gastrointestinal stromal tumours.

AIM: Gastrointestinal stromal tumours (GISTs) are uncommon mesenchymal neoplasms. Some metastasise, whereas others remain asymptomatic for years, but it is difficult to distinguish between them histologically. This report analyses the characteristics of seven metastasising GISTs and compares clinicopathological parameters of the metastatic and non-metastatic groups. METHODS/RESULTS: Histology revealed typical GIST features with spindle, epithelioid, or mixed appearance. All seven cases were positive for vimentin, five for neurone specific enolase, six for c-kit, four for S-100, three for PGP-9.5, three for CD-34 and synaptophysin, but all were negative for cytokeratin, neurofilament, chromogranin A, and desmin. Four showed a focal reaction for smooth muscle actin. Three of the tumours were GI, and two each were GII and GIII. The Ki-67 index varied from 4% to 44%, the three GI cases had 4%, 10%, and 16%. Tumours from the metastatic GIST group were significantly larger than those from the non-metastatic group. CONCLUSIONS: Three cases exhibited bland, GI histological features with moderate or low proliferative activity. Among the c-kit positive metastasising stromal tumours, some were low grade, with moderate or low mitotic and Ki-67 indices, emphasising the necessity to develop a reliable grading system for GIST to predict clinical behaviour, the importance of careful analysis of "benign looking" tumours, and the key role of c-kit status in identifying patients who could benefit from treatment with STI-571. Larger tumours had a higher chance of metastasising, and only the size of the primary tumour played a role in predicting metastatic potential.

Adult↗

Acute myeloid leukaemia of donor cell origin developing 5 years after allogeneic bone marrow transplantation for chronic myeloid leukaemia.

We report the case of a male patient with Ph-positive CML who developed AML 5 years after allogeneic BMT. Clinically, the AML seemed to develop on the basis of a myelodysplasia. The myeloid origin of blasts has been proven by immunophenotyping. The variable number of tandem repeats (VNTRs) and short tandem repeat (STR) showed donor-type haemopoiesis. The interphase FISH showed the XX genotype directly in the morphologically identifiable blasts and in the CD34-positive sorted bone marrow cells. This proved the new leukaemia to be of donor origin. The necessity of using multiple techniques and the advantage of combined immunophenotyping and FISH methods in this case is emphasized.

Acute Disease↗

[Severe necrotic processes of the penis and scrotum].

Authors summarise the two-decade experience of their department in severe tissue necrosis of penis and scrotum. Presented cases represent a shared field of urology with dermatology, infectology, nephrology and andrology. Tissue necrosis extended to different depth of the penis, from superficial skin and subcutaneous tissues, fascias to the entire organ. Underlying diseases are acute and chronic inflammations, metabolic diseases, vascular lesions. Diagnostic difficulties and therapeutic choices, both conservative and operative, are discussed.

Abscess↗

Cytogenetic abnormalities of alveolar soft-part sarcomas using interphase fluorescent in situ hybridization: trisomy for chromosome 7 and monosomy for chromosomes 8 and 18 seem to be characteristic of the tumor.

Four alveolar soft-part sarcomas were investigated by means of standard immunohistochemistry and interphase cytogenetics to further characterize the immunophenotype and proliferative activity of this tumor. The main goal of this study was to explore the chromosomal changes of this rare soft-tissue sarcoma. One epithelial (KLI), three neurogenic [neuron specific enolase (NSE), PGP 9.5, and S100], and five myogenic (desmin, myoglobin, alpha-smooth mnuscle actin, alpha-sarcomeric actin, and MyoD1) markers were used for the immunophenotypical analysis. Proliferative activity was assessed using the Ki67 index. Twelve (peri)centromeric (1, 3, 4, 6, 7, 8, 10, 12, 15, 17, 18, and X) and one telomeric (17q25-qtel.) chromosomal probes were used for interphase cytogenetic analysis. Three of the cases showed cytoplasmic desmin and/or myoglobin, and one showed smooth muscle actin positivity. All of the four tumors had granular, cytoplasmic, possibly nonspecific MyoD1 and sarcomeric actin positivity. Two of the tumors were positive for vimentin, four gave focal and weak staining with neurogenic markers (four of four NSE, one of four S100, and four of four PGP 9.5), but none of them was positive with KLI. Alveolar soft-part sarcomas may show myogenic immunophenotype in a number of cases, which supports myogenic differentiation. Fluorescent in situ hybridization using alpha satellite chromosomal probes revealed significant alterations in all of the cases. Most frequent and repeated numerical changes, which seem to be characteristic of the neoplasm and may play an important part in its pathogenesis and/or progression, were trisomy 7, monosomy 8 and monosomy 18.

Adolescent↗

Targeting acute ischemic stroke with a calcium-sensitive opener of maxi-K potassium channels.

During ischemic stroke, neurons at risk are exposed to pathologically high levels of intracellular calcium (Ca++), initiating a fatal biochemical cascade. To protect these neurons, we have developed openers of large-conductance, Ca++-activated (maxi-K or BK) potassium channels, thereby augmenting an endogenous mechanism for regulating Ca++ entry and membrane potential. The novel fluoro-oxindoles BMS-204352 and racemic compound 1 are potent, effective and uniquely Ca++-sensitive openers of maxi-K channels. In rat models of permanent large-vessel stroke, BMS-204352 provided significant levels of cortical neuroprotection when administered two hours after the onset of occlusion, but had no effects on blood pressure or cerebral blood flow. This novel approach may restrict Ca++ entry in neurons at risk while having minimal side effects.

Animals↗

Histiocytic necrotizing lymphadenitis preceding systemic lupus erythematosus.

Necrotizing histiocytic lymphadenopathy (NHL) is a rarely observed clinical entity that is occasionally associated with systemic lupus erythematosus (SLE). The histological features of the condition have been considered to be indistinguishable from those of lymphadenitis in subjects with SLE, and the clinical symptoms of the two disorders share common features. This report presents the case history of a subject who developed SLE with central nervous system involvement 3 years following onset of Kikuchi's disease (histiocytic necrotizing lymphadenitis). Repeated lymph node biopsies confirmed the diagnosis in relation to the clinical progression. A review of the literature on this topic is also presented.

Adrenal Cortex Hormones↗

Solid and papillary epithelial neoplasm arising in heterotopic pancreatic tissue of the mesocolon.

AIM: Solid and papillary epithelial neoplasm (SPEN) is an uncommon pancreatic tumour. Very rarely it has also been described outside the pancreas, usually arising from heterotopic pancreatic tissue. This report summarises all the published extrapancreatic SPENs and documents the sixth such case arising from heterotopic pancreatic tissue of the transverse mesocolon in a 15 year old girl. METHODS/RESULTS: Histological and immunohistochemical examination revealed typical papillary and solid areas composed of columnar, cuboidal, and round cells, which were focally positive for vimentin, cytokeratin, neurone specific enolase, carcinoembryonic antigen, alpha1-antitrypsin, alpha1-antichymotrypsin, and negative for neuroendocrine markers (neurofilament, PGP 9.5, chromogranin A, synaptophysin, and S100), p53, and oestrogen and progesterone receptors. Electron microscopy showed scant zymogen but no neurosecretory granules. In agreement with the flow cytometric result s of diploidy, comparative genomic hybridisation (CGH) did not reveal loss or gain of genetic material, and the in situ hybridisation analysis of the RB1 and p53 genes revealed no abnormality in the 13q and 17p arms. CONCLUSIONS: Immunohistochemical and electron microscopic data support exocrine differentiation. The CGH and the flow cytometric results suggest a subtle, yet unknown genetic change, rather than a large genetic alteration. RB1 and p53 in situ hybridisation ruled out the role of deletion at these sites in the pathogenesis of SPEN. Interestingly, review of the published and the present heterotopic pancreatic SPENs identified the mesocolon as the most common anatomical site (four of six), despite the very rare occurrence of ectopic pancreatic tissue at this site.

Adolescent↗

Autologous hematopoietic stem cell transplantation in chronic myeloid leukemia with different clinical stages.

Seven patients with Philadelphia (Ph) chromosome-positive chronic myeloid leukemia (CML) were treated with an ICE-based regimen plus G-CSF with the aim of mobilizing and collecting Ph-negative peripheral stem cells in the setting of an autologous transplant program. Five patients had CML in the first chronic phase and 2 in the accelerated phase. All patients had been previously treated with interferon-alpha. Median value and ranges for harvested mononuclear cells, CD34+ cells and CFU-GM, respectively: 5.65 x 10(8)/kg (2.61-11.38); 1.48 x 10(6)/kg (0.216-3.5), and 3.43 x 10(4)/kg (0.243-11.6). FISH was the only useful method for detection of minimal residual disease on apheresis product showing <5% t(9;22) positive cells in 2 cases and <10% positive cells in 4 other cases. Four of seven autologous grafts have been transplanted to date. Busulfan conditioning was used in 1 case and TBI/Cy conditioning in 3 other cases. All patients are alive and well following transplantation and are on interferon-alpha therapy.

Adult↗

[Autologous hematopoietic stem cell transplantation in chronic myeloid leukaemia with different clinical stages]

For most chronic myeloid leukaemia patients the option of a potentially curative allogeneic stem cell transplantation is not available because of age or lack of donor. Alternative therapy with interferon-alpha appears to prolong survival but is probably not curative. The aim of the study is to analyse the clinical results of the first Hungarian autologous transplantations in CML. METHODS: Seven patients were treated with ICE-based regimen plus G-CSF with the aim of mobilising and collecting Ph-negative peripheral stem cells in the setting of autologous transplant program. Five patients had CML in first chronic phase and two in accelerated phase. All patients have been previously treated with interferon-alpha. RESULTS: Median value and ranges for harvested mononuclear cells, CD34(+) cells and CFU-GM were: 5.65x10(8)/kg (2.61-11.38), 1.48x10(6)/kg (0.216-3.5) and 3.43x10(4)/kg (0.243-11.6), respectively. Four out of seven autologous grafts have been transplanted. Busulfan conditioning was used in one case and TBI/Cy conditioning in three patients. All patients are alive and well post-transplant being on interferon-alpha therapy. CONCLUSIONS: Based on the clinical advantages of autologous transplantation including long-term chronic phase, achievement of second chronic phase and improved response to interferon-alpha therapy, the procedure can offer an alternative treatment in CML in lack of HLA-identical donor.

Journal Article↗

Intravital microscopic assessment of pressure induced microcirculatory changes after enterocystoplasty in rats.

PURPOSE: Chronic over distention may lead to enterocystoplasty rupture. It is hypothesized that pressure induced microvascular derangement and subsequent ischemia of the enterocystoplasty intestinal patch may have a role in this process. We describe distention induced microcirculatory alterations in a chronic rat model of enterocystoplasty using intravital video microscopy. MATERIALS AND METHODS: Microcirculation in the muscle layer of the intact bladder and intestine, and in the enterocystoplasty 90 days after surgery were examined at greater and less than urethral sphincter closure pressure. Microcirculatory changes were recorded during stepwise increments of intraluminal pressure up to 80 mm. Hg or when 20 mm. Hg was continuously maintained for 60 minutes. RESULTS: The enterocystoplasty components of intestine and bladder displayed baseline microcirculatory characteristics similar to those observed in the intact organs. As evidenced by microcirculatory flow and functional capillary density measurements in the intact intestine and the ileal portion of enterocystoplasty, intraluminal pressure elevation to greater than 25 or 30 mm. Hg significantly compromised capillary perfusion by approximately 50% and 75%, respectively. Lower intraluminal pressure did not cause microcirculatory disturbance even when maintained for a longer period. In the intact bladder and bladder portion of enterocystoplasty only pressure increases to greater than 80 mm. Hg affected tissue perfusion. CONCLUSIONS: Intravital microscopy in the augmented rat bladder is a sensitive and suitable means of assessing clinically relevant microcirculatory changes. These experiments demonstrate the significance of distention induced microcirculatory impairment in the intact bowel and the intestinal site of enterocystoplasty even at less than urethral closure pressure.

Animals↗

[Successfully operated infraperitoneal hemangiopericytoma infiltrating the left ureter].

Hemangiopericytoma is a very rare tumour originating from the lining cells of small vessels. Despite benign histology it is clinical presentation similar to malignancy. There are only less than hundred cases reported sporadically in the literature. Authors report a case and successful radical removal of an infraperitoneal hemangiopericytoma infiltrating the left ureter. The literature of this strange, rare pathology is also analysed in the article.

Adult↗

[Hepatitis C virus infection and B-cell non-Hodgkin's lymphoma].

Oncogenesis is a multifactorial process in which environmental, genetical and infectious factors may be of importance. Specific viruses are supposed to have etiological role in about 15% of human tumors. Recently the B-cell proliferation inducing effect of the hepatotropic and lymphotropic hepatitis-C virus (HCV) came into the limelight based on the high prevalence of HCV positivity in B-cell non-Hodgkin's lymphoma (NHL) patients. The aim of the authors was to establish the prevalence of HCV infection in NHL patients. Paralelly the HBV, CMV and EBV markers, and the alterations of the humoral immune response (immunoglobulins, cryoglobulins, rheumatoid factor) were determined. 42 patients (24 male, 18 female; the mean age: 54.1 years, range 22-80 years) classified as 16 indolent (low risk), and 25 aggressive (intermediate risk) NHL and one with very aggressive Burkitt's lymphoma, according to the modified REAL classification were examined. Enzyme-linked immunosorbent assay (ELISA) for HBsAg and anti-HCV, HBsAg, anti EBV, anti CMV, furthermore polymerase chain reaction (PCR) for HCV-RNA were used. Anti-HCV was found in 6/42 NHL patients (14.3%), while anti-HCV and/or HCV-RNA PCR positivity revealed on overall HCV infection in 10/42 (23.8%) patients. None of them were HBsAg positive. Our findings support the hypothesis, that HCV might have an aetiological role in the lymphoproliferation leading to B-cell NHL.

Adult↗

[Treatment of chronic myeloid leukemia with interferon-alpha].

The authors have treated 38 patients with chronic phase chronic myeloid leukemia in their single center in the last five years. Conventional chemotherapy provided about 40-50% hematological response, interferon-alpha seems to be more effective, complete hematological remission occurred in 65%. Interphase cytogenetics and fluorescein in situ hybridisation technique was used to measure the cytogenetic response. They observed complete cytogenetic remission in two cases (8%), major response in 11 (39%), minor response in 4 (15%) and minimal response in 4 cases (15%). Interferon-alpha is an effective, well-tolerated medicine in the treatment of chronic myeloid leukemia.

Adolescent↗

[Molecular biology follow-up of interferon therapy in patients with chronic myeloid leukemia].

In a prospective survey clinical haematological and molecular biological data of 31 patients with chronic myelogenous leukaemia (chronic phase, CML) observed in their haematological outpatient department were analyzed. During 1996 and 1999 a regular follow-up of the Philadelphia chromosome level in treated patients was performed with molecular biological techniques, i.e. with reverse transcription polymerase chain reaction (RT-PCR) and with fluorescence in situ hybridization (FISH) methods. During the follow-up period of 33 months from the 31 patients with CML (16 males, 15 females) 25 ones were treated with human recombinant interferon-alpha (IFN), however, six others were getting only hydroxyurea (HU). During this period in three patients allogen bone marrow transplantation was performed and seven ones expired (six out of them of blastic crisis). The quality of therapeutic response at cytogenetical level was determined by decrease of the bcr-abl level due to the treatment (non-responders, major, minor and complete cytogenetic remission groups). In nine patients (five from the IFN-group, four from the HU-group) achieved no cytogenetic therapeutic response (non-responders, 29%). However, in 13 patients a minor (bcr-abl range of 60-30%), and in nine patients a maior/complete (bcr-abl of 30-10%) cytogenetic response (42% and 29%, respectively) were detected. Moreover, the quality of cytogenetic response correlated with the haematological remission. The maior/complete cytogenetic response was durable in eigth patients. The improvement of the overall survival of patients with CML, the postpone of the fatal accelerated-blastic phase could be expected only from the early introduced, in individually adjusted and given in maximally tolerated dosage of interferon (3-5 million UI/m2/day). The qualitative (RT-PCR) and quantitative (FISH) detections of the Philadelphia chromosome are reliably reproducible up-to-date molecular biological methods getting relevant results, which could be very helpful in the planning, monitoring, in setting of optimal dosage of the interferon therapy of patients with CML, in addition in the judgement of the effectiveness of the therapy, in the reduction of adverse effects, as well as in forecasting of the cytogenetic progression.

Antineoplastic Agents↗

[Complex molecular monitoring of chronic myeloid leukemia].

The authors have monitored the treatment of chronic myeloid leukaemia by simultaneous investigation of the residual tumour mass as well as the expression of the bcr-abl chimera. The first parameter was obtained by calculating the bcr-abl rearrangement positive cells as determined by fluorescent in situ hybridisation (FISH). The other value was determined by a quantitative (competitive) reverse transcription polymerase chain reaction (Q-RT-PCR). To avoid any inaccuracy associated with the variable yield of RNA isolation and reverse transcription, respectively, the amount of chimera mRNA was related to that of abl 2-3 transcript as internal control. The threshold for the sensitivity of the Q-RT-PCR procedure was 16 bcr-abl mRNA molecule/microgram RNA. The lowest relative concentration was represented by detecting 1 bcr-abl mRNA molecule out of 12,600 abl 2-3 transcripts. The analysis of peripheral blood samples of 33 untreated patients indicated that the amount of chimera mRNA changes between 80 and 1,000,000 molecules per microgram RNA and this parameter correlated hardly (r = -44) with the tumour load. Data from blood samples of 48 treated patients indicated that this four order of magnitude difference in the expression persists in that patient population which exhibited on average major cytogenetic and also in those without any cytogenetic response. In the individual patients not only correlated changes of residual tumour mass and chimera expression, but mainly independent changes of these two parameters were observed.

Chimera↗