Computed tomography anatomic predictors of outcomes in patients undergoing tricuspid transcatheter edge-to-edge repair

AIM

To identify anatomical computed tomography (CT) predictors of procedural and clinical outcomes in patients undergoing tricuspid transcatheter edge-to-edge repair (T-TEER).

METHODS AND RESULTS

Consecutive patients undergoing T-TEER between March 2018 to December 2022 who had cardiac CT prior to the procedure were included. CT scans were automatically analyzed using a dedicated software that employs deep learning techniques to provide precise anatomical measurements and volumetric calculations. Technical success was defined as successful placement of at least one implant in the planned anatomic location without single leaflet device attachment. Procedural success was defined as tricuspid regurgitation reduction to moderate or less. Procedural complexity was assessed by measuring the fluoroscopy time. The clinical endpoint was a composite of death, heart failure hospitalization, or tricuspid re-intervention throughout two years. A total of 33 patients (63.6% male) were included. Procedural success was achieved in 22 patients (66.7%). Shorter end-systolic (ES) height between the inferior vena cava (IVC) and tricuspid annulus (TA) (r ​= ​- 0.398, p ​= ​0.044) and longer ES RV length (r ​= ​0.551, p ​= ​0.006) correlated with higher procedural complexity. ES RV length was independently associated with lower technical(adjusted Odds ratio [OR] 0.812 [95% CI 0.665-0.991], p ​= ​0.040) and procedural success (adjusted OR 0.766, CI [0.591-0.992], p ​= ​0.043). Patients with ES right ventricular (RV) length of >77.4 ​mm had a four-fold increased risk of experiencing the composite clinical endpoint compared to patients with ES RV length ≤77.4 ​mm (HR ​= ​3.964 [95% CI, 1.018-15.434]; p ​= ​0,034]).

CONCLUSION

CT-derived RV length and IVC-to-TA height may be helpful to identify patients at increased risk for procedural complexity and adverse outcomes when undergoing T-TEER. CT provides valuable information for preprocedural decision-making and device selection.

Transesophageal Echocardiographic Planning and Neo-Left Ventricular Outflow Tract Assessment for Transcatheter Mitral Valve Implantation Using Novel Software

•New echo software aids periprocedural screening before transcather MV implantation. •Virtual valve can be directly projected in the 3D datasets. •It may be useful for patients unable to undergo contrast-enhanced CCT scans.

Quality and transparency of evidence for implantable cardiovascular medical devices assessed by the CORE-MD consortium

BACKGROUND AND AIMS

The European Union Medical Device Regulation 2017/745 challenges key stakeholders to follow transparent and rigorous approaches to the clinical evaluation of medical devices. The purpose of this study is a systematic evaluation of published clinical evidence underlying selected high-risk cardiovascular medical devices before and after market access in the European Union (CE-marking) between 2000 and 2021.

METHODS

Pre-specified strategies were applied to identify published studies of prospective design evaluating 71 high-risk cardiovascular devices in seven different classes (bioresorbable coronary scaffolds, left atrial appendage occlusion devices, transcatheter aortic valve implantation systems, transcatheter mitral valve repair/replacement systems, surgical aortic and mitral heart valves, leadless pacemakers, subcutaneous implantable cardioverter-defibrillator). The search time span covered 20 years (2000-21). Details of study design, patient population, intervention(s), and primary outcome(s) were summarized and assessed with respect to timing of the corresponding CE-mark approval.

RESULTS

At least one prospective clinical trial was identified for 70% (50/71) of the pre-specified devices. Overall, 473 reports of 308 prospectively designed studies (enrolling 97 886 individuals) were deemed eligible, including 81% (251/308) prospective non-randomized clinical trials (66 186 individuals) and 19% (57/308) randomized clinical trials (31 700 individuals). Pre-registration of the study protocol was available in 49% (150/308) studies, and 16% (48/308) had a peer-reviewed publicly available protocol. Device-related adverse events were evaluated in 82% (253/308) of studies. An outcome adjudication process was reported in 39% (120/308) of the studies. Sample size was larger for randomized in comparison to non-randomized trials (median of 304 vs. 100 individuals, P < .001). No randomized clinical trial published before CE-mark approval for any of the devices was identified. Non-randomized clinical trials were predominantly published after the corresponding CE-mark approval of the device under evaluation (89%, 224/251). Sample sizes were smaller for studies published before (median of 31 individuals) than after (median of 135 individuals) CE-mark approval (P < .001). Clinical trials with larger sample sizes (>50 individuals) and those with longer recruitment periods were more likely to be published after CE-mark approval, and were more frequent during the period 2016-21.

CONCLUSIONS

The quantity and quality of publicly available data from prospective clinical investigations across selected categories of cardiovascular devices, before and after CE approval during the period 2000-21, were deemed insufficient. The majority of studies was non-randomized, with increased risk of bias, and performed in small populations without provision of power calculations, and none of the reviewed devices had randomized trial results published prior to CE-mark certification.

Patient satisfaction, safety and efficacy of nurse-led compared to physician-led implantation of cardiac monitors

AIMS

Implantation of an implantable cardiac monitor (ICM) is a simple procedure, but adds significant and increasing workload to the arrhythmia service. In 2020, we established a nurse-led ICM implantation service. We aimed to analyze patient satisfaction, adverse events during implant and ICM re-interventions with nurse-led ICM implantation (N-Implant) compared to physician-led ICM implantation (P-Implant).

METHOD AND RESULTS

From January 2020 to December 2021 we included all consecutive patients implanted with an ICM in a prospective registry. We collected data on patient characteristics, implant procedure and follow-up. Patients were interviewed by phone four weeks after ICM implantation.Of 321 patients implanted with an ICM (median age 67 years; 33% women), 189 (59%) were N-Implants. More N-Implants were performed in the outpatient clinic compared to P-Implants (95% vs. 8%; p<0.001). Two N-Implant patients experienced vaso-vagal reaction during implantation (1%), whereas no adverse events occurred during P-Implant (p=0.51). 297 patients (93%) completed the questionnaire. Duration of pain was shorter and wound closure after 2 weeks better following N-Implant (p=0.019 and p=0.018). A minor bruise or swelling at the implant site was reported more frequently after N-Implant (p=0.003 and p=0.041). Patient satisfaction was excellent with both N-Implant and P-Implant (99% and 97%; p=0.16). After a median follow-up of 242 days (range 7-725 days), five ICMs (2%) were explanted prematurely, without differences among groups. Reasons for premature explants were local discomfort (n=2), infection, MRI and ICM malfunction.

CONCLUSION

Nurse-led ICM implantation has excellent patient satisfaction without compromising safety. N-Implant both expands nursing competencies and reduces physician workload.

Infectious Endocarditis of a Heterotopic Caval Valved Stent

Right-sided infective endocarditis (IE) accounts for 5% to 10% of all IE cases. Compared with left-sided IE, it is more often associated with intravenous drug abuse and intracardiac devices, whereas the latter has become more prevalent in recent decades. The authors report the first case of IE in a heterotopic caval valved stent used for treating torrential tricuspid regurgitation. (Level of Difficulty: Advanced.).

Natural history and mid-term prognosis of severe tricuspid regurgitation: A cohort study

Objectives

The objective of this study was to characterize a population of patients with severe tricuspid regurgitation (TR) evaluated at a tertiary care center, assess mid-term clinical outcomes, and identify prognostic factors.

Background

The impact of TR on morbidity and mortality is increasingly recognized. Clinical characteristics and long-term outcomes of patients suffering from TR remain unclear.

Methods

This is a retrospective observational single-center study from a tertiary care hospital including patients with echocardiographic diagnosis of severe TR between January 2017 and December 2018. We used the Kaplan-Meier method to estimate survival for up to 4 years. After excluding patients with tricuspid valve (TV) intervention and surgery during follow-up, a multivariate analysis was performed to assess predictors of 2-year mortality using the Cox regression model.

Results

A total of 278 patients (mean age 74.9 ± 13.7 years, 47.8% female) with severe TR were included in the study. The majority (83.1%; n = 231) had secondary TR. Comorbidities such as atrial fibrillation (AFib) (68.0%; n = 189), severe renal failure (44.2%; n = 123), pulmonary hypertension (PHT) (80.9%; n = 225), and right ventricular (RV) dysfunction (59.7%; n = 166) were highly prevalent. More than half of patients with a cardiac implantable electronic device (CIED) (54.3%; n = 44) showed echocardiographic signs of lead-leaflet interaction causing or contributing to TR. The estimated 2- and 4-year all-cause mortality was 50 and 69%, respectively. Using multivariate analysis, age, severe renal failure, heart failure with reduced ejection fraction (HFrEF), and vena contracta width ≥14 mm were identified as predictors of 2-year mortality. Nine percent (n = 25) of the study cohort underwent transcatheter or surgical treatment for TR during follow-up.

Conclusion

Our study shows the high burden of morbidity and the dismal survival of patients with severe TR. It also highlights the extent of the therapeutic need, since the vast majority of patients were left untreated. Additionally, CIED RV lead-associated TR was prevalent suggesting a need for more attention in clinical routine and research.

Association of heart failure and liver T1 mapping in cardiac magnetic resonance imaging

Background

Heart failure culminates in liver congestion. As the liver can be assessed by cardiac magnetic resonance T1 mapping sequences, it represents a promising imaging biomarker for heart failure.

Objectives

To evaluate the association between heart failure and magnetic resonance liver T1 mapping, as a non-invasive imaging surrogate of liver congestion.

Methods

Patients with cardiac magnetic resonance including T1 mapping sequences on a single 1.5T scanner were consecutively included between 01/2017 and 12/2019. Liver T1 was measured in the left lobe, right lobe and caudate lobe on short axis view and in the liver dome on four chamber view. Echocardiographic and laboratory parameters were analyzed within 90 days of the cardiac magnetic resonance exam. Left ventricular filling pressures were assessed according to the European Association of Cardiovascular Imaging guidelines [1]. Liver T1 and echocardiographic parameters were compared between patients with and without elevated NT-proBNP levels (&gt;125 pg/ml) using a Mann-Whitney U test. A multivariate logistic regression model was used to correct for age, sex, body mass index, left ventricular ejection fraction and the presence of atrial fibrillation.

Results

A total of 397 patients were included (median age 56, 127 females), of whom 138 patients (35%) presented with elevated NT-proBNP levels. Patients with elevated NT-proBNP levels had a larger indexed end-diastolic left ventricular volume (92 vs. 81 ml/m2, p&lt;0.001), lower left ventricular ejection fraction (60 vs. 50%, p&lt;0.001) and a higher E/E' ratio (11 vs. 8, p&lt;0.001). Liver T1 was higher in patients with elevated NT-proBNP in the right liver lobe (670 vs. 596 ms, p&lt;0.001) and the caudate lobe (664 vs. 598 ms, p&lt;0.001), but not in the left liver lobe (571 vs. 568 ms, p=0.068) and in the liver dome (590 vs. 560 ms, p=0.1). Echocardiographic evaluation showed similar results with significant difference in T1 times between patients with elevated and non-elevated left ventricular filling pressures in caudate and right liver lobe. Liver T1 retained its predictive value when corrected for age, left ventricular ejection fraction and the presence of atrial fibrillation, when measured in the caudate lobe (adjusted odds ratio 1.013, 95% confidence interval 1.004–1.023, p=0.005) and in the right lobe (adjusted odds ratio 1.012, 95% confidence interval 1.003–1.021, p=0.009).

Conclusions

Elevated liver T1 in cardiac magnetic resonance imaging is associated with heart failure and represents an independent non-invasive imaging surrogate for liver congestion.

Funding Acknowledgement

Type of funding sources: None.

Evolution of tricuspid valve regurgitation after implantation of a leadless pacemaker - a single center experience, systematic review and meta-analysis

Introduction

Conventional transvenous pacemaker leads may interfere with the tricuspid valve leaflets, tendinous chords, and papillary muscles, resulting in significant tricuspid valve regurgitation (TR). Leadless pacemakers (LLPMs) theoretically cause less mechanical interference with the tricuspid valve apparatus. However, data on TR after LLPM implantation are sparse and conflicting. Our goal was to investigate the prevalence of significant TR before and after LLPM implantation.

Methods

Patients who received a leadless LLPM (Micra™ TPS, Medtronic) between May 2016 and May 2021 at our center were included in this observational study if they had at least a pre‐ and postinterventional echocardiogram (TTE). The evolution of TR severity was assessed. Following a systematic literature review on TR evolution after implantation of a LLPM, data were pooled in a random‐effects meta‐analysis.

Results

We included 69 patients (median age 78 years [interquartile range (IQR) 72–84 years], 26% women). Follow‐up duration between baseline and follow‐up TTE was 11.4 months (IQR 3.5–20.1 months). At follow‐up, overall TR severity was not different compared to baseline (p = .49). Six patients (9%) had new significant TR during follow‐up after LLPM implantation, whereas TR severity improved in seven patients (10%). In the systematic review, we identified seven additional articles that investigated the prevalence of significant TR after LLPM implantation. The meta‐analysis based on 297 patients failed to show a difference in significant TR before and after LLPM implantation (risk ratio 1.22, 95% confidence interval 0.97–1.53, p = .11).

Conclusion

To date, there is no substantial evidence for a significant change in TR after implantation of a LLPM.

Nurse-led compared to physician-led implant of cardiac monitors

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Implantation of an implantable cardiac monitor (ICM) is a simple and straightforward procedure. However, with a growing demand for such implants, workload significantly increases. In January 2020, we established a completely nurse-led ICM implantation service (N-IMPLANT) with a standard operating procedure.

Purpose

The present study aimed to analyze the safety, efficacy, and patient satisfaction of N-IMPLANT compared to implantation of ICMs by a physician (P-IMPLANT).

Method

Consenting patients implanted with an ICM were included in a prospective registry, which collects patient characteristics, procedural and remote monitoring data. All patients were followed-up by phone interview four weeks after ICM implantation and a standardized questionnaire was completed.

Results

Of 321 patients implanted with an ICM (median age 67 years; 33% women), 189 (59%) were N-IMPLANT. Significantly more N-IMPLANT were performed in the outpatient clinic compared to P-IMPLANT (94% vs. 10%; p&lt;0.001). For wound closure, N-IMPLANT used wound glue in 65 (34%) and a single subcutaneous stitch in 124 patients (66%). Two N-IMPLANT patients experienced vaso-vagal reaction during implantation, whereas no adverse events occurred during P-IMPLANT (p=0.51). Two-hundred and fifty-two patients (79%) completed the questionnaire. We found no difference between N-IMPLANT and P-IMPLANT regarding pain after implant, analgesic use, wound closure after 2 weeks and presence and size of patient reported hematoma (see Table). Duration of pain was longer after P-IMPLANT. All N-IMPLANT patients indicated to be satisfied with the implant procedure. Three patients were dissatisfied with P-IMPLANT for the following reasons: ongoing pain at implant site; discomfort at implant site; and too numerous people present during the implant procedure. In three N-IMPLANT (2%) the ICM was explanted prematurely. The reasons for explantation were infection (with reimplantation of another ICM), discomfort at implant site and attempt to avoid interferences during magnetic resonance tomography in one patient each. One P-IMPLANT (1%) was explanted prematurely because of ICM malfunction.

Conclusion

Nurse-led implantation of cardiac monitors is effective without compromising patient safety and has excellent patient satisfaction. N-IMPLANT is a suitable model to reduce the workload of physicians.

Assessment of New Onset Arrhythmias After Transcatheter Aortic Valve Implantation Using an Implantable Cardiac Monitor

Background

Transcatheter aortic valve implantation (TAVI) is associated with new onset brady- and tachyarrhythmias which may impact clinical outcome.

Aims

To investigate the true incidence of new onset arrhythmias within 12 months after TAVI using an implantable cardiac monitor (ICM).

Methods

One hundred patients undergoing TAVI received an ICM within 3 months before or up to 5 days after TAVI. Patients were followed-up for 12 months after discharge from TAVI for the occurrence of atrial fibrillation (AF), bradycardia (≤30 bpm), advanced atrioventricular (AV) block, sustained ventricular and supraventricular tachycardia.

Results

A previously undiagnosed arrhythmia was observed in 31 patients (31%) and comprised AF in 19 patients (19%), advanced AV block in 3 patients (3%), and sustained supraventricular and ventricular tachycardia in 10 (10%) and 2 patients (2%), respectively. Three patients had a clinical diagnosis of sick-sinus-syndrome. A permanent pacemaker (PPM) was implanted in six patients (6%). The prevalence of pre-existing AF was 28%, and 47% of the patients had AF at the end of the study period. AF burden was significantly higher in patients with pre-existing [26.7% (IQR 0.3%; 100%)] compared to patients with new-onset AF [0.0% (IQR 0.0%; 0.06%); p = 0.001]. Three patients died after TAVI without evidence of an arrhythmic cause according to the available ICM recordings.

Conclusions

Rhythm monitoring for 12 months after TAVI revealed new arrhythmias, mainly AF, in almost one third of patients. Atrial fibrillation burden was higher in patients with prevalent compared to incident AF. Selected patients may benefit from short-term remote monitoring.

Trial Registration

https://clinicaltrials.gov/: NCT02559011.

Diagnostic performance of quantitative coronary artery disease assessment using computed tomography in patients with aortic stenosis undergoing transcatheter aortic-valve implantation

BACKGROUND

Computed tomography angiography (CTA) is a cornerstone in the pre- transcatheter aortic valve replacement (TAVI) assessment. We evaluated the diagnostic performance of CTA and coronary artery calcium score (CACS) for CAD evaluation compared to invasive coronary angiography in a cohort of TAVI patients.

METHODS

In consecutive TAVI patients without prior coronary revascularization and device implants, CAD was assessment by quantitative analysis in CTA. (a) Patients with non-evaluable segments were classified as obstructive CAD. (b) In patients with non-evaluable segments a CACS cut-off of 100 was applied for obstructive CAD. The reference standard was quantitative invasive coronary angiography (QCA, i.e. ≥ 50% stenosis).

RESULTS

100 consecutive patients were retrospectively included, age was 82.3 ± 6.5 years and 30% of patients had CAD. In 16% of the patients, adequate visualization of the entire coronary tree (all 16 segments) was possible with CTA, while 84% had at least one segment which was not evaluable for CAD analysis due to impaired image quality. On a per-patient analysis, where patients with low image quality were classified as CAD, CTA showed a sensitivity of 100% (95% CI 88.4-100.0), specificity of 11.4% (95% CI 5.1-21.3), PPV of 32.6% (95% CI 30.8-34.5), NPV of 100% and diagnostic accuracy of 38% (95% CI 28.5-48.3) for obstructive CAD. When applying a combined approach of CTA (in patients with good image quality) and CACS (in patients with low image quality), the sensitivity and NPV remained at 100% and obstructive CAD could be ruled out in 20% of the TAVI patients, versus 8% using CTA alone.

CONCLUSION

In routinely acquired pre-TAVI CTA, the image quality was insufficient in a high proportion of patients for the assessment of the entire coronary artery tree. However, when adding CACS in patients with low image quality to quantitative CTA assessment in patients with good image quality, obstructive CAD could be ruled-out in 1/5 of the patients and may therefore constitute a strategy to streamline pre-procedural workup, and reduce risk, radiation and costs in selected TAVI patients without prior coronary revascularization or device implants.

Retrograde Retrieval of a Novel Large Mitral Clip After Embolization Into the Left Ventricle

We describe the successful retrieval of a novel large mitral clip, which embolized in a patient with severe secondary mitral regurgitation and left ventricular dysfunction, dilated left ventricle, and severely tethered mitral valve leaflets in the setting of a challenging anatomy for transcatheter edge-to-edge repair. The description highlights planning, technical issues, and possible adverse events of this bailout procedure. (Level of Difficulty: Intermediate.)

The impact of obesity on left ventricular hypertrophy and diastolic dysfunction in children and adolescents

Childhood obesity continues to escalate worldwide and may affect left ventricular (LV) geometry and function. The aim of this study was to investigate the impact of obesity on prevalence of left ventricular hypertrophy (LVH) and diastolic dysfunction in children. In this analysis of prospectively collected cross-sectional data of children between 5 and 16 years of age from randomly selected schools in Peru, parameters of LV geometry and function were compared according to presence or absence of obesity (body mass index z-score > 2). LVH was based on left ventricular mass index (LVMI) adjusted for age and sex and defined by a z-score of > 2. LV diastolic function was assessed using mitral inflow early-to-late diastolic flow (E/A) ratio, peak early diastolic tissue velocities of the lateral mitral annulus (E′), early diastolic transmitral flow velocity to tissue Doppler mitral annular early diastolic velocity (E/E′) ratio, and left atrial volume index (LAVI). Among 1023 children, 681 children (mean age 12.2 ± 3.1 years, 341 male (50.1%)) were available for the present analysis, of which 150 (22.0%) were obese. LVH was found in 21 (14.0%) obese and in 19 (3.6%) non-obese children (p_adjusted < 0.001). LVMI was greater in obese than that in non-obese children (36.1 ± 8.6 versus 28.7 ± 6.9 g/m^2.7, p < 0.001). The mean mitral E/E′ ratio and LAVI were significantly higher in obese than those in non-obese individuals (E/E′: 5.2 ± 1.1 versus 4.9 ± 0.8, p_adjusted = 0.043; LAVI 11.0 ± 3.2 versus 9.6 ± 2.9, p_adjusted = 0.001), whereas E′ and E/A ratio were comparable. Childhood obesity was associated with left ventricular hypertrophy and determinants of diastolic dysfunction.

ClinicalTrials.gov Identifier: NCT02353663.

The altered expression of α1 and β3 subunits of the gamma-aminobutyric acid A receptor is related to the hepatitis C virus infection

The modulation of the gamma-aminobutyric acid type A (GABA A) receptors activity was observed in several chronic hepatitis failures, including hepatitis C. The expression of GABA A receptor subunits α1 and β3 was detected in peripheral blood mononuclear cells (PBMCs) originated from healthy donors. The aim of the study was to evaluate if GABA A α1 and β3 expression can also be observed in PBMCs from chronic hepatitis C (CHC) patients and to evaluate a possible association between their expression and the course of hepatitis C virus (HCV) infection. GABA A α1- and β3-specific mRNAs presence and a protein expression in PBMCs from healthy donors and CHC patients were screened by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. In patients, HCV RNA was determined in sera and PBMCs. It was shown that GABA A α1 and β3 expression was significantly different in PBMCs from CHC patients and healthy donors. In comparison to healthy donors, CHC patients were found to present an increase in the expression of GABA A α1 subunit and a decrease in the expression of β3 subunit in their PBMCs. The modulation of α1 and β3 GABA A receptors subunits expression in PBMCs may be associated with ongoing or past HCV infection.

Expression of microRNA-155 precursor in peripheral blood mononuclear cells from Hepatitis C patients after antiviral treatment

Chronic hepatitis caused by Hepatitis C virus (HCV) is the main source of liver cirrhosis, hepatocellular carcinoma, and extra-hepatic diseases. After treatment-induced resolution of hepatitis C, the persistence of HCV RNA in serum and peripheral blood mononuclear cells (PBMCs) is often observed. An expression of the precursor of microRNA-155 (miR-155) called BIC can be the factor responsible for a course of HCV infection. Therefore, we assessed the relationship between BIC expression and HCV RNA status in sera and PBMCs samples of 64 hepatitis C patients treated with interferon alpha(IFN-alpha)+ribavirin. High expression of BIC in PBMCs was determined in 100% of patients that harbored HCV RNA in serum and PBMCs. Further, we found that 83% of PBMCs samples were BIC-positive in a group of patients that eliminated HCV RNA only from serum. The lowest expression of BIC was found in patients that eliminated HCV RNA from both serum and PBMCs.

Primary cutaneous marginal zone B-cell lymphoma in a patient with chronic lymphocytic leukaemia

Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is a low-grade malignant lymphoma that presents in the skin with no evidence of extracutaneous localization at diagnosis. We present an 80-year-old woman with B-cell chronic lymphocytic leukaemia (CLL) who developed multifocal PCMZL lesions 14 months after CLL diagnosis. PCMZL was clonally similar to the original bone marrow (BM) CLL cells. The specific translocation t(14;18) (q32;q21) with breakpoints in IGH and BCL2 loci was found in a skin specimen, but was absent in BM and peripheral blood (PB) cells. In contrast, a 13q deletion was found in BM and PB CLL cells. The patient was treated with chlorambucil and complete response of PCMZL was achieved. To our knowledge this is the first patient with CLL in whom PCMZL has been diagnosed.

Various dietary fats differentially change the gene expression of neuropeptides involved in body weight regulation in rats

Various high-fat diets are obesogenic but not to the same extent. The aim of the present study was to investigate the effects of saturated fat n-6 and n-3 polyunsaturated fatty acids (PUFAs) on the central neuropeptidergic system in adult rats. Using reverse transcriptase-polymerase chain reaction and in situ hybridisation, we evaluated the net effect of feeding in these fats, comparing the effects of a high- to low-fat diet, and the diversity of the effects of these fats in the same amount within the diet. We also determined plasma lipids, glucose, insulin and leptin concentrations. Six-week feeding with high-saturated fat evoked hyperpahagia and the largest weight gain compared to both high-PUFA diets. Rats fed high-saturated fat were found to have decreased neuropeptide Y (NPY) mRNA expression in the arcuate nucleus (ARC) and the compact zone of the dorsomedial nucleus (DMHc), unchanged pro-opiomelanocortin (POMC), galanin-like peptide (GALP) mRNA expression in the ARC, as well as melanin-concentrating hormone (MCH) and prepro-orexin (preORX) mRNA expression in the lateral hypothalamus, compared to low-saturated fed rats. By contrast, feeding with both high-PUFA diets increased POMC and GALP mRNA expression in the ARC compared to the corresponding low-fat diet and the high-saturated fat diet. Furthermore, feeding with both low-PUFA diets reduced NPY mRNA expression compared to the low-saturated fat diet exclusively in the DMHc. Uniquely, the high n-3 PUFA feeding halved MCH and preORX mRNA expression in the lateral hypothalamus compared to the other high-fat and low n-3 PUFA diets. In rats fed three high-fat diets, plasma insulin and leptin concentrations were significantly increased and the type of fat had no effect on these hormone levels. Rats fed high-saturated fat had both hyperglycaemia and hypertriacylglycerolemia and rats fed high n-3 PUFA only had hyperglycaemia. The present study demonstrates that various forms of dietary fat differentially change the expression of neuropeptide genes involved in energy homeostasis.

Richter syndrome first manifesting as cutaneous B-cell lymphoma clonally distinct from primary B-cell chronic lymphocytic leukaemia

Richter syndrome (RS) is a transformation to high-grade non-Hodgkin lymphoma in patients with chronic lymphocytic leukaemia (CLL). RS may develop in lymph nodes or rarely extranodally. Skin localization of RS has been described in only a few cases. We present a 77-year-old woman who developed isolated diffuse large B-cell lymphoma (LBCL) in the skin of the nose without any other symptoms of RS. The LBCL in the skin was clonally distinct from the original bone marrow CLL cells. Moreover, LBCL cells were positive for LMP-1 segment of Epstein-Barr virus and overexpressed p53 protein. The patient was successfully treated with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) and adjuvant local radiotherapy.

A new recombinant thrombolytic and antithrombotic agent with higher fibrin affinity--a staphylokinase variant. I. In vitro study

We attempted to construct a new recombinant protein characterized by fibrin-specific properties of plasminogen activation combined with antithrombin and antiplatelet activities. To the C-terminal part of recombinant staphylokinase (r-SAK), which is a promising profibrinolytic agent, we assembled: (i) the Kringle 2 domain (K2) of tissue-type plasminogen activator (t-PA), containing a fibrin-specific binding site, (ii) the RGD sequence (Arg-Gly-Asp) for the prevention of platelet aggregation and (iii) the antithrombotic agent - hirudin. The cDNA for hybrid protein SAK-RGD-K2-Hir was cloned into pESP-3 yeast protein expression vector. The introduction of K2 t-PA, RGD sequence and hirudin into r-SAK molecule did not alter the SAK activity. The plasminogen activation rate (determined by K(M) and K(cat)) of SAK-RGD-K2-Hir was not significantly different from that of r-SAK. Affinity and binding strength of the recombinant protein to fibrin immobilized on the biosensor were higher than to r-SAK. We observed a higher clot lysis potency of SAK-RGD-K2-Hir as evidenced by a faster and more profound lysis of 125I-labeled human fibrin clots. The potency of thrombin inhibition by the hirudin part of the recombinant fusion protein SAK-RGD-K2-Hir was the same as that of r-Hir alone. In conclusion, the results of the in vitro study suggest that the SAK-RGD-K2-Hir construct can be a more potent and faster-acting thrombolytic agent with antithrombin and antiplatelet properties compared with standard r-SAK.

A comparative study of P53/MDM2 genes alterations and P53/MDM2 proteins immunoreactivity in liver cirrhosis and hepatocellular carcinoma

In the present study, the expression of P53 and MDM2 proteins were examined in specimens from a group of 20 patients (9 with primary hepatocellular carcinoma HCC and 11 with liver cirrhosis LC, linked to HBV infections as a major aetiologic factor) by immunohistochemistry. The immunostaining findings were correlated with P53 mutation analysis using PCR-SSCP, PCR-HDF and direct sequencing, and MDM2 amplification studies by differential PCR. P53 immunopositivity was found in 9 out of the 20 (45.0%) cases. Mutations of the P53 gene were detected in 5 (55%) tumors and 3 (27%) LC samples; 7 of these cases revealed P53 immunoreactivity. The mutations were base transitions at codons 175, 245 and 273; no changes were observed at codon 249, characteristic for aflatoxins action. MDM2 immunopositivity was revealed in 9 out of 20 (45.0%) specimens. MDM2 amplification occurred in 4 (44.4%) and 1 (9.1%) cases, HCC and LC specimens respectively; only in 2 tumors (10.0%), which exhibited MDM2 immunoreactivity. Overall, MDM2 positivity was not associated with MDM2 amplification in 7 out of the 20 studied samples (35.0%). Two HCC patients were found to have both gene abnormalities. Either the mutation rate of the P53 gene as well as the amplification level of the MDM2 gene was higher in HCC than in precancerous liver tissue stages. These results support the notion that besides P53 alterations, MDM2 gene deregulation seems to be an important event in hepatocarcinogenesis. Additionally, the mechanism of MDM2-mediated degradation of P53 protein, without involving stabilization and inactivation of P53 gene, should be considered for the understanding of all features of tumor progression processes.

Abnormalities of the P53, MDM2, BCL2 and BAX genes in acute leukemias

Abnormalities of the P53 network have been implicated in the pathogenesis of acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML). The purpose of this study was to define P53 gene mutations, to detect MDM2 gene amplification and to estimate mRNA expression of P53, MDM2, BCL2 and BAX genes in patients with ALL and AML. Twenty-five patients with ALL and 65 patients with AML, both recently diagnosed, were included into this study. Exons 5-8 of the P53 gene with flanking intronic sequence were amplified by the polymerase chain reaction (PCR) method and subjected to mutation screening by single-strand conformation polymorphism analysis (SSCP). Mutation of the P53 gene was found in one patient of the 25 with ALL and in five patients of the 65 with AML. Sequence analysis was subsequently performed. One mutation in intronic sequence in ALL and four missense mutations and one silent nucleotide substitution in AML were identified. Amplification of MDM2 gene was detected by multiplex-PCR analysis in only one sample from patient with ALL, but was not observed in any case of AML. To gain further insight into the role of P53 network in the evolution of acute leukemias, the P53, MDM2, BCL2 and BAX mRNAexpressions in portion samples from patients with ALL and AML were analyzed using multiplex RT-PCR. Although a low frequency of molecular disturbances of the P53 and the MDM2 genes was detected in this study, there was a high percentage of cases with increased mRNA level of P53 and MDM2. A high frequency of BCL2 mRNA overexpression and a relatively low frequency of BAX mRNA overexpression detected in both analyzed leukemias in this study, indicate that altered transcription of these genes may be involved in leukemogenesis.

Microsatellite instability and expression of DNA mismatch repair genes in malignant astrocytic tumors from adult and pediatric patients

Microsatellite instability (MSI) is used as a molecular marker for defective DNA mismatch repair (MMR) genes. We report here alterations of MSI in 15 malignant astrocytomas (WHO grade III) and glioblastomas (GBM; WHO grade IV) of pediatric patients (2 - 21 years) and 12 GBM from adults (44 - 68 years) by comparative analysis of BAT25/BAT26 loci and 10 other microsatellite markers. High-level microsatellite instability (MSI-H) occurred in 4 of the 15 pediatric cases (26.7%) and in 1 of the 12 adult GBM cases (8.3%). Low-level microsatellite instability (MSI-L) was observed in 6 pediatric cases (40%) and 8 adult GBM (66.7%). Unstable BAT-25 locus was found in 1 of the MSI-H pediatric cases. Thus, 2 unstable cases showed no instability of this marker. For BAT-26, such a discordance was even more profound: in 1 of MSI-H cases, we obtained no PCR product and the remaining 3 showed no alterations of this marker. MSH2 (Human MutS, Homologue2) protein was detected in all but 3 pediatric cases (1 highly unstable and 2 low-level unstable) and in all adult cases. MLH1 (Human MutL, Homologue 1) protein was detected in all but 2 pediatric cases (1 highly unstable and 1 low-level unstable). Thus, 2 highly unstable pediatric cases showed no detectable MLH1/MSH2 proteins. Our data support earlier observations that MSI occurs predominantly in malignant astrocytic tumors of young patients, which lends support to the hypothesis of different molecular mechanisms of pediatric brain tumors. Surprisingly, we found no significant correlation between the status of 10 microsatellite markers and that of either BAT25 or BAT26 loci or with the expression of MMR genes.

p65 and c-erbB2 genes expression in breast tumors: comparison with some histological typing, grading and clinical staging

Using PCR technique we have analyzed p65 and c-erbB2 genes expression in 47 frozen tissue slides taken from patients diagnosed as ductal and lobular breast cancer, classified as G3, and in a limited panel of proliferative breast disease cases. Expression of p65 was generally connected with small tumor size and with absence of metastases in regional lymph nodes. We have found interdependence between p65 gene expression and negative states of lymph nodes. On the contrary, c-erbB2 expression was observed in patients with large tumors and with metastases to the regional lymph nodes. Between both genes (p65 and c-erbB2) opposite interdependence was found. No statistical dependence between estrogen/progesterone receptor levels and p65 or c-erbB2 expression were noticed. The presence of p65 expression appeared in the group of proliferating breast disease cases which were connected with higher risk of breast cancer. Lack of p65 expression accompanied cases which were classified as fibroadenoma.

Expression of gene encoding P65 oncofetal protein in acute and chronic leukemias

In this study we have established conditions for p65 gene expression analysis by reverse transcriptase polymerase chain reaction (RT-PCR). On the basis of this technique we analyzed p65 gene expression in various types of leukemia: acute myeloblastic leukemia (AML) (n=26); acute lymphoblastic leukemia (ALL) (n=26) and chronic lymphocytic leukemia (CLL) (n=40). The highest frequency of p65 gene expression was found in the patients with CLL (66%). No relationship between the expression of p65 gene and clinical stage of leukemia was observed. The lower percentage of positivity (presence of gene transcript) was seen in patients with ALL (42%) and AML (46%).

Successful treatment of leukaemia cutis with cladribine in a patient with B-cell chronic lymphocytic leukaemia

Cutaneous presentation of B-cell chronic lymphocytic leukaemia (B-CLL) is uncommon, and the influence of skin changes on B-CLL prognosis is unclear. We report a patient with B-CLL Rai II, with multiple nodular skin infiltrations on the trunk, upper arms and thighs as well as constitutional symptoms, who was successfully treated with cladribine. The peripheral blood (PB) lymphocytes were CD19, CD20, CD23 and CD5 positive, which confirmed the diagnosis of B-CLL. Skin biopsy of one of the lesions showed an intense infiltrate composed of small lymphocytes with no epidermotropism. These cells also showed the expression of CD19, CD20, CD23 and CD5 antigens similar to those presented on PB lymphocytes. Polymerase chain reaction performed on bone marrow lymphocytes and a lesional skin biopsy using consensus primers for immunoglobulin heavy-chain genes also showed the same monoclonal population of B lymphocytes both in the bone marrow and in the skin. The patient received four courses of cladribine 0.12 mg kg-1 daily as a 2-h infusion for five consecutive days. The courses were repeated at monthly intervals. The lymphocytosis gradually decreased and the PB count normalized after three courses. At the same time, a significant decrease in the cutaneous symptoms was observed. The patient became free of skin tumours after the fourth course of cladribine; only slight discoloration at the previous sites of cutaneous infiltration remained. There was no relapse of leukaemia cutis during a further 7 months of observation.

Molecular diversity of gammadelta T cells in peripheral blood from patients with B-cell chronic lymphocytic leukaemia

To characterize circulating gammadelta T cell subpopulations in B chronic lymphocytic leukaemia patients (n=30), TCR Vgamma and Vdelta gene-segment use was analyzed by RT-PCR using a panel of subfamily-specific oligonucleotide primers. All results were compared with those obtained with specimens from healthy donors (n=10). The cells expressing Vdelta1+ TCR displayed the highest relative increase in B-CLL patients (particularly observed in 60% of cases), but Vdelta3+ T lymphocytes also expanded in leukaemic peripheral blood (10% of studied cases). Both mentioned gammadelta T cell subsets were significantly more frequent in the most severe stages of disease--Rai III+IV. The analysis of Vgamma region usage in TCR formation revealed that gammadelta T cells from B-CLL patients predominantly expressed a Vgamma9 segment (26 of 30 cases), usually linked to Cgamma1 region. It should be noticed that the dominant TCR genes expression in a 50% of healthy donors was Vdelta2+/Vgamma9+, however, Vgamma4 and Vgamma8 transcripts were also observed (2 and 3 of 10 cases, respectively). The above results indirectly indicate that gammadelta T lymphocyte expansion was driven by the oligo- or polyclonal proliferation and can reflect specific response against the autologous tumor cells.

[Involvement of WT1 gene expression in regulation of P53 and MDM2 proteins function in acute lymphoblastic leukemia]

Using sensitive techniques such as reverse transcription polymerase chain reaction (RT-PCR) the expression of WT1 gene in acute lymphoblastic leukemias (ALL) is indicated. High level of mRNA WT1 was only observed in ALL cases with leukemic cells characterized by P53- and MDM2-positive staining in cytometric analysis. The overexpression of P53 protein has not been induced by P53 gene abnormalities and MDM2 protein synthesis was independent from respective gene amplification. The data suggest that WT1 may play a distinct role in the pathophysiology of acute leukemias. It can regulate the function of the main oncoprotein network factors--P53 and MDM2 proteins. There was concluded that the most important mechanism of tissue P53-immunopositivity was connected with the P53 interactions with other oncoproteins, especially with MDM2 and WT1. They have caused different effects in particular cases and several phenotypes of leukemic cells were described. However, the negative tissue staining with anti-P53 monoclonal antibodies can not be evidence of the proper P53 protein function. The immunohistochemical estimations of the P53 level in the cells are insufficient for diagnostic and clinical evaluations. Molecular analyses of P53 and MDM2 genes, as well the WT1 gene transcription, are necessary for the proper characterisation of functional and structural status of P53.

Plasmablastic lymphoma in a patient with chronic lymphocytic leukemia heavily pretreated with cladribine (2-CdA): an unusual variant of Richter's syndrome

Patients with chronic lymphocytic leukemia (CLL) may develop a large-cell transformation known as Richter's syndrome (RS). RS usually presents as diffuse large-cell lymphoma (DLCL) or its immunoblastic variant, and it can be recognized simultaneously with CLL or even 23 yr after its diagnosis. We describe an unusual case of CLL treated with cladribine (2-CdA) in whom DLCL of the plasmablastic type (PBL) developed 4 yr after CLL (Rai IV) diagnosis and 1.5 yr after the 10th course of 2-CdA treatment. Immmunologic, cytogenetic, and molecular studies performed at the time of CLL and PBL coappearance indicated that both tumors originated from different B-cell progenitors. Both malignancies were refractory to VAD (vincristine, doxorubicin, dexamethasone)-based chemotherapy, and only partial response was achieved with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) salvage treatment. However, the patient died 6 months after the occurrence of RS due to rapid progression of PBL. This is the first description of a CLL patient who developed an unusual plasmablastic variant of RS. Recently, the PBL entity has been identified among DLCL associated with the human immunodeficiency virus (HIV) infection. We suggest that in our CLL patient heavily pretreated with 2-CdA, PBL arose as a second clone due to the prolonged and severe state of the host's immunosuppression. Overall survival with current strategies is poor, and further insight into the natural history, biology, and treatment of PBL are needed.

Lymphocyctes Tgammadelta in clinically normal skin and peripheral blood of patients with systemic lupus erythematosus and their correlation with disease activity

Human Tgammadelta lymphocytes constitute from 1 to 15% of all peripheral blood lymphocytes. Recent work has demonstrated that this population plays a major role in the pathogenesis of infectious and immune diseases. Increased numbers of gammadelta T cells have been found in affected skin from systemic sclerosis and chronic cutaneous lupus erythematosus patients. In our study, we have determined the numbers of Tgammadelta lymphocytes and their subpopulations in peripheral blood from 29 patients with systemic lupus erythematosus (SLE) and in 19 healthy volunteers using flow cytometry and specific monoclonal antibodies. The same cells in uninvolved skin from SLE patients and human controls using immunohistochemical analysis were estimated. T-Cell receptor (TCR) delta chain gene rearrangement was identified with primers for Vdelta1, Vdelta2 and Vdelta3 by the polymerase chain reaction. Statistical analysis showed a significantly decreased number of gammadelta T cells in SLE patients (26.4+/-16.9/microl) compared with the control group (55.3+/-20.6/microl (p < 0.001). The number of Vdelta2 TCR+ and Vgamma9 TCR+ subpopulations was also lower in SLE patients than in healthy persons. No statistical correlation between disease activity and the number of gammadelta T cells was demonstrated. The percentage of Tgammadelta lymphocytes in clinically normal skin from SLE patients was twice (22.0+/-9.4%) that found in the skin from healthy persons (11.1+/-5.5%) (p < 0.002). Higher percentages of the Vdelta2 TCR+ and Vgamma9 TCR+ subpopulation of lymphocytes were found in the skin from SLE patients. We have also found positive correlation between the percentage of Tgammadelta lymphocytes in skin and the activity of SLE (r=0.594, p < 0.001), and between subpopulation Vdelta3 TCR+ and disease activity (r=0.659, p< 0.001). In conclusion, the results of our studies demonstrate that, in patients with SLE, accumulation of Tgammadelta lymphocytes can be seen in clinically normal skin, and the percentage of these cells correlates with the activity of the disease.

Richter's syndrome following cladribine therapy for chronic lymphocytic leukemia first manifested as pathologic fracture of the femur

Richter's syndrome (RS) refers to the development of aggressive non-Hodgkin's lymphoma (NHL) during the course of chronic lymphocytic leukaemia (CCL). It occurs in approximately 3% of patients with CLL. The isolated form of this complication in bone is extremely rare and, so far, has not been described in a patient treated with cladribine (2-CdA). We report a case of CLL treated successfully with 2-CdA, where isolated diffuse large B-cell lymphoma (LBCL) developed 2 years after the diagnosis of CLL Rai II and one year after the completion of 2-CdA treatment. RS was first manifested as a pathologic fracture of the left femur. The LBCL was clonally distinct from the original CLL cells. The patient was successfully treated with CHOP and radiotherapy and obtained complete response of the LBCL.

Low-grade non-Hodgkin's lymphoma in a patient with systemic lupus erythematosus

Coexistence of systemic lupus erythematosus (SLE) with low-grade non-Hodgkin's lymphoma (LGNHL) has been described occasionally in the literature with the potential pathogenetic role of monoclonal B CD5+/CD19+ cells. We report a case of LGNHL which developed 18 months after diagnosis of SLE. The monoclonal population of lymphocytes in the peripheral blood and bone marrow was CD5/CD19 negative but CD19/CD22 positive. The SLE responded well to treatment with prednisone and the course of the LGNHL was stable and cytotoxic treatment was not required.

Medullary thyroid carcinoma (MTC)--clinical and molecular aspects on the basis of own experience

In our clinic 19615 patients were operated over 25 years on for goiter. Malignant thyroid neoplasms were found in 1049 (5.3%) patients including 875 (83.4%) women and 174 (16.6%) men. Sixty two adult patients (42 women and 20 men were operated on for medullary thyroid carcinoma (MTC). Thyroid cancer was diagnosed in this group pre or intraoperatively in 44 (71%) patients and postoperatively, on histologic examination, in 18 (29%) patients. These patients were reoperated. Radical operations (total thyroidectomy with regional lymph node removal) were conducted in 43 (69.3%) patients and palliative ones in 19 (30.7%) patients. After MTC surgery, MEN 2A (MTC and an adrenal tumor) were diagnosed by means of imaging techniques (USG, CT) in 6 (9.7%) patients. All adrenal tumors were unilateral. Five of these patients were operated, and pheochromocytoma was confirmed by histopathologic examination. Two years after the MTC operation, 1 women was lost to follow-up. After a year, she was admitted to hospital for severe hypertension and died of cerebral hemorrhagia. Pheochromocytoma was revealed by autopsy. All patients were treated complementarily after the MTC operation. Different combinations of teleradiotherapy, chemotherapy and substitutive doses of levothyroxine were used. Ten (23.2%) of 43 patients operated radically were reoperated 1-3 years after the first operation due to loco-regional tumor recurrence. Radical reoperations were performed in 4 patients, and palliative ones in 6. Over a 0.5-23-year follow-up period, 26 (41.9%) patients died, including 20 of cancer, and 6 of other reasons. Four out of 36 living patients have clinical or biochemical symptoms of neoplastic disease. The follow-up period of MEN 2 patients operated on ranged from 1 to 6 years. Up to now, no tumor in the second adrenal gland has been diagnosed in any of these patients. Genetic (molecular) tests performed in 31 out of 36 living patients revealed mutations of RET gene in 4 (12.9%).

[Familial occurrence of nephroblastoma]

Wilms' tumour can develop in ways: sporadic--non-hereditary or familial. Familial Wilms' tumour is not very seldom. It is a form of autosomal dominant segregation and probably low and variable penetration. Up to now it has not been observed in the presence of characteristic genetic changes. Taking into consideration the case of the patient with positive family interview we presented the way of diagnosing and treating the child. Moreover we presented the results of cytogenetic examination and molecular analyses (loss of heterozygosity of WT1 gene and loss of heterozygosity 16 q), which had not shown any changes. We also discussed the actual level of knowledge abut familial form of Wilms' tumour.

[Antitumor activity of gamma delta T lymphocytes]

Increasing knowledge about the role played by gamma delta T lymphocytes in antitumor immunity is of importance to both the fundamental and clinical sciences. gamma delta T cells are also characterized with reference to theirself neoplastic transformation and development of leukemias or lymphomas with gamma delta fenotype.

16q heterozygosity loss in Wilms' tumour in children and its clinical importance

INTRODUCTION

The loss of heterozygosity (LOH) of 16q is a structural change detected in about 20-30% of Wilms' tumour cases. Aberrations which result in deletion of 16q are also found in breast cancer, prostate cancer and liver cancer, where they are connected with a worse prognosis. The hypothesis of a bad prognosis in nephroblastomas with LOH 16q was first formulated by scientists from NWTS (National Wilms Tumor Study) on the basis of 232 cases of Wilms' tumour. However, SIOP studies (International Society of Paediatric Oncology) which included 28 cases of Wilms' tumour, did not show any clinico-pathological correlations with LOH 16q. Therefore, we aimed to evaluate the importance of LOH 16q in relation to clinico-pathological factors in a group of children, treated according to the SIOP criteria.

AIMS

The aim of this work was to evaluate the frequency of LOH 16q in sporadic unilateral Wilms' tumour and to study the relationship between LOH 16q and selected patho-clinical parameters. The study comprised 66 children (31 girls and 35 boys) aged from 2 days to 13 years.

METHODS

LOH 16q was studied by the examination of polymorphism of marker sequences in the region 16q24. DNA was isolated from paraffin sections of tissue for routine microscopic examination by the microdissection method. The method of study involved the amplification of polymorphic sequences from the 16q24 region by polymerase chain reaction (PCR) and separation of the products of amplification by polyacrylamide gel electrophoresis. The results were the subject of statistical analysis in relation to gender, age of child at first diagnosis, stage of clinical advancement and histological type of tumour. The connection between LOH 16q and recurrences, metastases and death, and failure free survival and absolute survival of children followed-up for over 24 months after nephrectomy were studied.

RESULTS

The study revealed a lack of correlation between LOH 16q and gender, however LOH 16q was more frequent in children with Wilms' tumour aged >24 months, P<0.05. Also, LOH 16q was more frequent in tumours classified as clinical stage (CS) II or III than in CS I, P<0.05, but there were no differences in the occurrence of LOH 16q in tumours classified as CS II and CS III. We have found no correlation between LOH 16q and the histological type of tumour. However, LOH 16q has been found three times as frequently in tumours from children who died than in tumours of children who survived, P<0.0024.

Atypical chronic myelogenous leukemia following immunosuppressive therapy for severe aplastic anemia

Late clonal complications of aplastic anemia (AA) such as acute leukemia, myelodysplastic syndromes or paroxysmal nocturnal hemoglobinuria have been recognized for a long time. To our knowledge, chronic myelogenous leukemia (CML) as a late complication of severe aplastic anemia has as yet not been reported. We report here a case of AA treated successfully with antilymphocytic globulin and cyclosporin in whom Ph1 negative, BCR/ABL negative CML developed 8 years after diagnosis of AA. This case of atypical, secondary CML was refractory to treatment with interferon alpha and hydroxyurea.

Malignant fibrous histiocytomas and H-ras-1 oncogene point mutations

AIMS

To investigate the types and the frequencies of H-ras-1 gene mutations in malignant fibrous histiocytomas.

METHODS

Thirty five samples of malignant fibrous histiocytoma tissue were searched for point mutations within "hot spot" codons 12 and 13 of the H-ras-1 oncogene by the specific "nested" polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and a direct cycle sequencing procedure.

RESULTS

In contrast to previous reports, none of the tumours contained a point mutation or any other changes within or around the hot spot gene sequences.

CONCLUSIONS

These data indicate that H-ras-1 oncogenic activation is not required in the molecular pathway of malignant fibrous histiocytoma formation and cannot be used as a discriminating factor for diagnostic sarcoma typing.

Loss of heterozygosity of WT1 gene in the prognosis of sporadic Wilms' tumour in children

The aim of this report was to evaluate the prognostic value of allele loss of the WT1 gene in children with sporadic Wilms' tumour. Allele loss of the WT1 gene was evaluated using microsatellite polymorphisms in the 3' untranslated region of WT1 in a radioactive PCR assay. The study comprised 66 children (30 girls and 36 boys), aged from 2 days to 13 years, treated for Wilms' tumour according to the SIOP-09 and PGGL scheme. We have used DNA isolated from the neoplastic versus normal kidney tissue from the paraffin embedded sections using microdissection procedure. Loss of heterozygosity (LOH) of the WT1 gene was found in 12 children (19.6%), 5 cases were non-informative. No significant correlation could be found between the LOH of WT1 gene and sex and age. Significantly more frequent occurrence of LOH in tumor in low stage of advancement and low degree of malignancy was found. However, no significant effect of LOH of WT1 gene was observed on frequency of recurrences, metastasis and deaths. Study of allele loss of the WT1 gene may be recommended in difficult cases as an additional factor useful for the diagnosis and in the assignment of the tumour to the appropriate risk group.

Circulating TCR gammadelta cells in the patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a disorder with a wide range of immunological abnormalities. The results of the studies undertaken in the last decade indicated that SLE pathogenesis was mainly connected with the breakdown of the activation control of B and T cells, generating humoral or cell-mediated responses against several self-antigens of affected cells. The last studies demonstrate that the role of gammadelta T lymphocytes in autoimmune diseases can be especially important. Flow cytometry techniques were used to investigate the number and percentage of TCR gammadelta T cells and their most frequent subtypes in peripheral blood of 32 patients with SLE and 16 healthy volunteers. We also correlated TCR gammadelta cells number with the level of T CD3+, T CD4+, T CD8+, and NK (CD16) cells (cytometric measurements) and SLE activity (on the basis of clinical investigations). Our studies were preliminary attempts to evaluate the role of that minor T cell subpopulation in SLE. Absolute numbers of cells expressing gammadelta TCR in most SLE blood specimens were significantly lower than in the control group (P<0.006). However, since the level of total T cell population was also decreased in the case of SLE, the mean values of the percentage gammadelta T cells of pan T lymphocytes were almost the same in both analysed populations (7.1% vs 6.3%, respectively). In contrast to Vdelta2+ and Vgamma9+ subtypes of pan gammadelta T cells, Vdelta3+ T cells number was higher in SLE patients (20 x 10 cells/microl) than in healthy control group (2 x 2 cells/microl) (P=0.001). However, we found no differences between the numbers of pan gammadelta T lymphocytes and studied their subtypes in the patients with active and inactive disease. These cell subpopulations were doubled in the treated patients with immunosuppressive agents in comparison with untreated ones; however, data were not statistically significant. Our study indicated that Vdelta3+ subtype of gammadelta T cells seems to be involved in SLE pathogenesis; however, we accept the idea that the autoimmunity does not develop from a single abnormality, but rather from a number of different events.

A comparative study of epidermal growth factor receptor (EGFR) and MDM2 gene amplification and protein immunoreactivity in human glioblastomas

The gene of epidermal growth factor receptor (EGFR) is often altered in human astrocytomas and its amplification, rearrangement and overexpression occur almost exclusively in high grade tumours (glioblastomas). MDM2 gene is amplified in a small proportion of glioblastomas, and MDM2 immunoreactivity has also been found in this group. However, the relation between gene amplification and protein overexpression depends on several factors. Thus, the study on mutual relationship between these events needs to be clarified. In a series of 28 glioblastomas, we analysed MDM2 and EGFR gene amplification by differential PCR and protein overexpression was evaluated by immunohistochemistry. Thirteen cases (45%) presented immunopositivity for EGFR. A significant amplification of EGFR gene (the EGFR/SOD ratio above the control value +/- 3 SD) was observed in 9 tumours among which, one revealed no EGFR-immunopositivity. Three tumours displayed the ratio +/- 2-3 SD but these tumours also presented immunoreactivity for EGFR. Two other glioblastomas, with weak EGFR-expression, showed no gene amplification. The immunohistochemical staining for MDM2 revealed strong positivity only in one case, and this tumour also presented MDM2 gene amplification. On the contrary, another tumour which showed MDM2 gene amplification showed no MDM2 immunopositivity. In conclusion, our results demonstrate that there is no strict correlation between gene amplification at the DNA level and protein overexpression.

Evidence for B cell-mediated activation of V delta 1+ T lymphocytes during progression of HIV infection

Progression of HIV-induced immunodeficiency is associated with both B cell activation and an increased proportion of Vdelta1+ T cells in PBL. To examine whether the peripheral expansion of Vdelta1+ cells is driven by activated B cells, we isolated CD19+ PBL from HIV+ individuals at different stages of infection and used them to stimulate Vdelta1+ T cell clones. The Vdelta1+ T cell clones were isolated from HIV+ individuals and selected on the basis of cytotoxic activity and IFN-gamma expression in response to lymphoblastoid cell lines (LCLs) established from patients with AIDS (AIDS-related LCLs) but not LCLs of HIV- donors. Peripheral blood B cells from HIV+ patients induced IFN-gamma expression in these Vdelta1+ clones, and their stimulatory ability was associated with up-regulated expression of the CD38 activation Ag and with a 6- to 10-fold increased spontaneous Ig production. Stimulation of CD19+ PBL from HIV+ individuals with cross-linked anti-CD40 mAb or rgpl20 further augmented induction of IFN-gamma expression in the Vdelta1+ cells. The isolated Vdelta1+ T cell clones expressed the Jdelta1 gene segment, but differed in Vgamma gene segment usage and in the junctional region of TCR-delta chains, indicating Vdelta gene-determined recognition. These results provide evidence that the peripheral expansion of Vdelta1+ cells in HIV infection is associated with phenotypic and functional alterations of B cells, due to chronic activation during progression to AIDS.

Evidence for B cell-mediated activation of V delta 1+ T lymphocytes during progression of HIV infection

Progression of HIV-induced immunodeficiency is associated with both B cell activation and an increased proportion of Vdelta1+ T cells in PBL. To examine whether the peripheral expansion of Vdelta1+ cells is driven by activated B cells, we isolated CD19+ PBL from HIV+ individuals at different stages of infection and used them to stimulate Vdelta1+ T cell clones. The Vdelta1+ T cell clones were isolated from HIV+ individuals and selected on the basis of cytotoxic activity and IFN-gamma expression in response to lymphoblastoid cell lines (LCLs) established from patients with AIDS (AIDS-related LCLs) but not LCLs of HIV- donors. Peripheral blood B cells from HIV+ patients induced IFN-gamma expression in these Vdelta1+ clones, and their stimulatory ability was associated with up-regulated expression of the CD38 activation Ag and with a 6- to 10-fold increased spontaneous Ig production. Stimulation of CD19+ PBL from HIV+ individuals with cross-linked anti-CD40 mAb or rgpl20 further augmented induction of IFN-gamma expression in the Vdelta1+ cells. The isolated Vdelta1+ T cell clones expressed the Jdelta1 gene segment, but differed in Vgamma gene segment usage and in the junctional region of TCR-delta chains, indicating Vdelta gene-determined recognition. These results provide evidence that the peripheral expansion of Vdelta1+ cells in HIV infection is associated with phenotypic and functional alterations of B cells, due to chronic activation during progression to AIDS.

Cytokine patterns during progression to AIDS in children with perinatal HIV infection

Patterns of cytokine expression were analyzed in polyclonal and antigenic responses in children with perinatal HIV infection. Responses of PBL to PMA and A23187 calcium ionophore studied in patients in different stages of HIV infection revealed reduced levels of IL-2 in HIV-infected children beginning before 6 mo of age, and age-dependent increases in expression of IL-4, IL-10, and IFN-gamma. The levels of IL-4, IL-10, and IFN-gamma expression did not differ significantly between HIV-infected and age-matched uninfected children of HIV-seropositive mothers, except for a small reduction in HIV-infected children in late stages of infection. Responses to PHA, HLA alloantigens, HIV envelope peptides T1 and P18, and tetanus toxoid were studied in PBMC derived from asymptomatic and mildly symptomatic HIV-infected children. IL-2, IFN-gamma, IL-4, and IL-5 expression was detected in PHA-stimulated PBMC from all analyzed patients. HIV-infected children who failed to respond to HLA alloantigens, tetanus toxoid, or the envelope peptides had lower numbers of CD4+ cells and expressed, on PHA stimulation, higher levels of IL-4 and IL-5 and lower levels of IL-2 and IFN-gamma than patients who responded to the antigenic stimulation. Results of these analyses suggest that cytokine expression in HIV-infected children depends on the character of the stimuli as well as the phenotype of PBMC, and indicate possible prevalence of Th2 Ag-specific responses during the progression of HIV-induced immunodeficiency.

Cytokine patterns during progression to AIDS in children with perinatal HIV infection

Patterns of cytokine expression were analyzed in polyclonal and antigenic responses in children with perinatal HIV infection. Responses of PBL to PMA and A23187 calcium ionophore studied in patients in different stages of HIV infection revealed reduced levels of IL-2 in HIV-infected children beginning before 6 mo of age, and age-dependent increases in expression of IL-4, IL-10, and IFN-gamma. The levels of IL-4, IL-10, and IFN-gamma expression did not differ significantly between HIV-infected and age-matched uninfected children of HIV-seropositive mothers, except for a small reduction in HIV-infected children in late stages of infection. Responses to PHA, HLA alloantigens, HIV envelope peptides T1 and P18, and tetanus toxoid were studied in PBMC derived from asymptomatic and mildly symptomatic HIV-infected children. IL-2, IFN-gamma, IL-4, and IL-5 expression was detected in PHA-stimulated PBMC from all analyzed patients. HIV-infected children who failed to respond to HLA alloantigens, tetanus toxoid, or the envelope peptides had lower numbers of CD4+ cells and expressed, on PHA stimulation, higher levels of IL-4 and IL-5 and lower levels of IL-2 and IFN-gamma than patients who responded to the antigenic stimulation. Results of these analyses suggest that cytokine expression in HIV-infected children depends on the character of the stimuli as well as the phenotype of PBMC, and indicate possible prevalence of Th2 Ag-specific responses during the progression of HIV-induced immunodeficiency.

Gene transfer studies of T cell receptor-gamma delta recognition. Specificity for staphylococcal enterotoxin A is conveyed by V gamma 9 alone

gamma delta T cells bearing the V gamma 9 gene segment have been shown to recognize staphylococcal enterotoxin A (SEA) and a range of other Ags including mycobacterial Ags. We have established an experimental system to analyze the recognition properties of human TCR-gamma delta on a molecular level by transferring the receptor from its original T cell into a Jurkat T cell host that does not express an endogenous TCR. Three groups of transfectants that express the same delta-chain, V delta 1, but different gamma-chains (V gamma 9-J2-C gamma 2, V gamma 3-J2-C gamma 2, and V gamma 9-JP-C gamma 1) together with the endogenous CD3 were obtained. The transfectant T cells each expressing different gamma delta receptors all produced IL-2 after stimulation with plastic bound anti-CD3 Ab, but only those expressing V gamma 9 responded to stimulation with SEA in the presence of an autologous lymphoblastoid B cell line. In addition, transfectants that expressed V delta 2 combined with V gamma 9 could also respond to SEA. These results indicate that the V gamma 9 portion of the receptor, independent of the J region and C region or the delta-chain, is responsible for recognizing SEA.

Gene transfer studies of T cell receptor-gamma delta recognition. Specificity for staphylococcal enterotoxin A is conveyed by V gamma 9 alone

gamma delta T cells bearing the V gamma 9 gene segment have been shown to recognize staphylococcal enterotoxin A (SEA) and a range of other Ags including mycobacterial Ags. We have established an experimental system to analyze the recognition properties of human TCR-gamma delta on a molecular level by transferring the receptor from its original T cell into a Jurkat T cell host that does not express an endogenous TCR. Three groups of transfectants that express the same delta-chain, V delta 1, but different gamma-chains (V gamma 9-J2-C gamma 2, V gamma 3-J2-C gamma 2, and V gamma 9-JP-C gamma 1) together with the endogenous CD3 were obtained. The transfectant T cells each expressing different gamma delta receptors all produced IL-2 after stimulation with plastic bound anti-CD3 Ab, but only those expressing V gamma 9 responded to stimulation with SEA in the presence of an autologous lymphoblastoid B cell line. In addition, transfectants that expressed V delta 2 combined with V gamma 9 could also respond to SEA. These results indicate that the V gamma 9 portion of the receptor, independent of the J region and C region or the delta-chain, is responsible for recognizing SEA.