Oxidative metabolism drives inflammation-induced platinum resistance in human ovarian cancer.

Tumour cells have long been considered defective in mitochondrial respiration and mostly dependent on glycolytic metabolism. However, this assumption is currently challenged by several lines of evidence in a growing number of tumours. Ovarian cancer (OC) is one of the most lethal cancers worldwide, but it continues to be a poorly understood disease and its metabolic features are far to be elucidated. In this context, we investigated the role of tumour necrosis factor receptor-associated protein 1 (TRAP1), which is found upregulated in several cancer types and is a key modulator of tumour cell metabolism. Surprisingly, we found that TRAP1 expression inversely correlated with grade, stage and lower survival in a large cohort of OC patients. Accordingly, TRAP1 silencing induced resistance to cisplatin, resistant cells showed increased oxidative metabolism compared with their sensitive counterpart, and the bioenergetics cellular index of higher grade tumours indicated increased mitochondrial respiration. Strikingly, cisplatin resistance was reversible upon pharmacological inhibition of mitochondrial oxidative phosphorylation by metformin/oligomycin. At molecular level, increased oxidative metabolism in low TRAP1-expressing OC cells and tissues enhanced production of inflammatory mediators such as interleukin (IL)-6 and IL-8. Mechanistically, we identified members of the multidrug resistance complex (MDR) as key mediators of such metabolism-driven, inflammation-induced process. Indeed, treatment of OC cell lines with TNFα and IL6 induced a selective increase in the expression of TAP1 and multidrug resistance protein 1, whereas TAP1 silencing sensitized cells to cisplatin-induced apoptosis. Our results unveil a novel role for TRAP1 and oxidative metabolism in cancer progression and suggest the targeting of mitochondrial bioenergetics to increase cisplatin efficacy in human OC.

Lymph node ratio and surgical quality are strong prognostic factors of rectal cancer: results from a single referral centre.

AIM: Nodal stage is a strong prognostic factor of oncological outcome of rectal cancer. To compensate for the variation in total number of harvested nodes, calculation of the lymph node ratio (LNR) has been advocated. The aim of the study was to compare the impact, on the long-term oncological outcome, of the LNR with other predictive factors, including the quality of total mesorectal excision (TME) and the state of the circumferential resection margin. METHOD: Consecutive patients having elective surgery for nonmetastatic rectal cancer were extracted from a prospectively maintained database. Retrospective uni- and multivariate analyses were performed based on patient-, surgical- and tumour-related factors. The prognostic value of the LNR on overall survival (OS) and on overall recurrence-free survival (ORFS) was assessed and a cut-off value was determined. RESULTS: From 1998 to 2013, out of 456 patients, 357 with nonmetastatic disease were operated on for rectal cancer. Neoadjuvant radiochemotherapy was administered to 66.7% of the patients. The mean number of lymph nodes retrieved was 12.8 ± 8.78 per surgical specimen. A lower lymph node yield was obtained in patients who received neoadjuvant chemoradiotherapy (11.8 vs 14.2; P = 0.014). The 5-year ORFS was 71.8% and the 5-year OS was 80.1%. Multivariate analysis confirmed LNR, the quality of TME and age to be independent prognostic factors of OS. LNR, age and perineural infiltration were independently associated with ORFS. Low- and high-risk patients could be discriminated using an LNR cut-off value of 0.2. CONCLUSION: LNR is an independent prognostic factor of OS and ORFS. In line with the principles of optimal surgical management, the quality of TME and lymph node yield are essential technical requirements.

Estimation of coronary flow reserve by sestamibi imaging in patients with mild hypertension and normal coronary arteries.

AIM: Patients with hypertension may exhibit abnormal vasodilator capacity during pharmacological vasodilatation. We assessed coronary flow reserve (CFR) by sestamibi imaging in hypertensive patients with normal coronary vessels. METHODS: Twenty-five patients with untreated mild essential hypertension and normal coronary vessels and 10 control subjects underwent dipyridamole-rest Tc-99m sestamibi imaging. Myocardial blood flow (MBF) was estimated by measuring first transit counts in pulmonary artery and myocardial counts from tomograhic images. CFR was expressed as the ratio of stress to rest MBF. Coronary vascular resistances (CVR) were computed as the ratio between mean arterial pressure and MBF. RESULTS: Estimated MBF at rest was not different in patients and controls (1.11 ± 0.59 vs. 1.14 ± 0.28 counts/pixel/s; P=0.87). Conversely, stress MBF was lower in patients than in controls (1.55 ± 0.47 vs. 2.68 ± 0.53 counts/pixel/s; P<0.001). Thus, CFR was reduced in patients compared to controls (1.61 ± 0.58 vs. 2.43 ± 0.62; P<0.001). Rest and stress CVR values were higher in patients (P<0.001), while stress-induced changes in CVR were not different (P=0.08) between patients (-51%) and controls (-62%). In the overall study population, a significant relation between CFR and stress-induced changes in CVR was observed (r=-0.86; P<0.001). CONCLUSION: Sestamibi imaging may detect impaired coronary vascular function in response to dipyridamole in patients with untreated mild essential hypertension and normal coronary arteries. A mild increase in arterial blood pressure does not affect baseline MBF, but impairs coronary reserve due to the amplified resting coronary resistances.

Translational control in the stress adaptive response of cancer cells: a novel role for the heat shock protein TRAP1.

TNF receptor-associated protein 1 (TRAP1), the main mitochondrial member of the heat shock protein (HSP) 90 family, is induced in most tumor types and is involved in the regulation of proteostasis in the mitochondria of tumor cells through the control of folding and stability of selective proteins, such as Cyclophilin D and Sorcin. Notably, we have recently demonstrated that TRAP1 also interacts with the regulatory protein particle TBP7 in the endoplasmic reticulum (ER), where it is involved in a further extra-mitochondrial quality control of nuclear-encoded mitochondrial proteins through the regulation of their ubiquitination/degradation. Here we show that TRAP1 is involved in the translational control of cancer cells through an attenuation of global protein synthesis, as evidenced by an inverse correlation between TRAP1 expression and ubiquitination/degradation of nascent stress-protective client proteins. This study demonstrates for the first time that TRAP1 is associated with ribosomes and with several translation factors in colon carcinoma cells and, remarkably, is found co-upregulated with some components of the translational apparatus (eIF4A, eIF4E, eEF1A and eEF1G) in human colorectal cancers, with potential new opportunities for therapeutic intervention in humans. Moreover, TRAP1 regulates the rate of protein synthesis through the eIF2α pathway either under basal conditions or under stress, favoring the activation of GCN2 and PERK kinases, with consequent phosphorylation of eIF2α and attenuation of cap-dependent translation. This enhances the synthesis of selective stress-responsive proteins, such as the transcription factor ATF4 and its downstream effectors BiP/Grp78, and the cystine antiporter system xCT, thereby providing protection against ER stress, oxidative damage and nutrient deprivation. Accordingly, TRAP1 silencing sensitizes cells to apoptosis induced by novel antitumoral drugs that inhibit cap-dependent translation, such as ribavirin or 4EGI-1, and reduces the ability of cells to migrate through the pores of transwell filters. These new findings target the TRAP1 network in the development of novel anti-cancer strategies.

TRAP1 and the proteasome regulatory particle TBP7/Rpt3 interact in the endoplasmic reticulum and control cellular ubiquitination of specific mitochondrial proteins.

Tumor necrosis factor receptor-associated protein-1 (TRAP1) is a mitochondrial (MITO) antiapoptotic heat-shock protein. The information available on the TRAP1 pathway describes just a few well-characterized functions of this protein in mitochondria. However, our group's use of mass-spectrometric analysis identified TBP7, an AAA-ATPase of the 19S proteasomal subunit, as a putative TRAP1-interacting protein. Surprisingly, TRAP1 and TBP7 colocalize in the endoplasmic reticulum (ER), as demonstrated by biochemical and confocal/electron microscopic analyses, and interact directly, as confirmed by fluorescence resonance energy transfer analysis. This is the first demonstration of TRAP1's presence in this cellular compartment. TRAP1 silencing by short-hairpin RNAs, in cells exposed to thapsigargin-induced ER stress, correlates with upregulation of BiP/Grp78, thus suggesting a role of TRAP1 in the refolding of damaged proteins and in ER stress protection. Consistently, TRAP1 and/or TBP7 interference enhanced stress-induced cell death and increased intracellular protein ubiquitination. These experiments led us to hypothesize an involvement of TRAP1 in protein quality control for mistargeted/misfolded mitochondria-destined proteins, through interaction with the regulatory proteasome protein TBP7. Remarkably, expression of specific MITO proteins decreased upon TRAP1 interference as a consequence of increased ubiquitination. The proposed TRAP1 network has an impact in vivo, as it is conserved in human colorectal cancers, is controlled by ER-localized TRAP1 interacting with TBP7 and provides a novel model of the ER-mitochondria crosstalk.

Myocarditis mimicking acute myocardial infarction: role of endomyocardial biopsy in the differential diagnosis.

OBJECTIVE: To test the hypothesis, using endomyocardial biopsies, that unexplained cases of apparent acute myocardial infarction were caused by myocarditis. MATERIAL: Between 1992 and 1998, 12 patients were admitted to the coronary care unit with severe chest pain, ST segment elevation, increased serum creatine kinase and MB isoenzyme, and with wall motion abnormalities on echocardiogram highly suggestive of acute myocardial infarction. These patients were further investigated by endomyocardial biopsy, as their coronary angiograms were normal. A diagnosis of myocarditis was made according to the Dallas criteria. A panel of antibodies was used for immunohistochemical characterisation of inflammatory cell infiltrate. Polymerase chain reaction (PCR) was used to detect viral genomes in seven cases. RESULTS: Haematoxylin and eosin staining of the endomyocardial biopsy showed active myocarditis in six patients and borderline myocarditis in one. Immunohistochemistry was positive for inflammatory cell infiltrates in 11 patients, including all the seven who were positive on haematoxylin and eosin staining according to the Dallas criteria. Only one patient had no evidence of inflammation. PCR was positive in two patients, both for Epstein-Barr virus. Follow up showed complete resolution of echocardiographic abnormalities in all patients except one. CONCLUSIONS: Myocarditis can mimic acute myocardial infarction in patients with angiographically normal coronary arteries, leading to errors of treatment. In patients with apparent myocardial infarction and a normal coronary angiogram, endomyocardial biopsy may help in the diagnosis of myocarditis. The sensitivity of endomyocardial biopsy was enhanced by using immunohistochemical and molecular biological techniques.

[Improvement of short-term prognosis in patients with refractory heart failure]. / Miglioramento della prognosi a breve termine dei pazienti con scompenso cardiaco refrattario.

BACKGROUND: Prognosis of patients with severe heart failure is poor, despite improved results in medical therapy. Heart transplantation is the only treatment possible in end-stage heart failure. The aim of this study was to evaluate the variation in prognosis over the past six years in the patients admitted to Intensive Care Unit for heart failure in spite of optimal oral therapy. STUDY POPULATION AND METHOD: Between January 1990 and December 1995, 133 patients with heart failure were admitted to the Intensive Care Unit, despite the fact that they were on optimal oral therapy. All patients were in New York Heart Association (NYHA) functional class III to IV and required intravenous administration of sympathomimetic amines, in addition to standard heart failure treatment procedures. Cumulative survival at six months of patients observed between 1990-1992 (group A) was compared with the survival rate of patients observed from 1993 to 1995 (group B). RESULTS: Clinical and haemodynamic parameters were similar in groups A and B, but ACE-inhibitors were used more frequently in group B (75 vs 31% respectively, p < 0.05). During the follow-up period, heart transplantation was indicated in a similar percentage of patients (A 53% vs B 58%). However, mortality on the waiting list (58% group A vs 21% group B; p < 0.05) and the percentage of patients who underwent heart transplantation (41% group A vs 78% group B; p < 0.05) differed. Moreover, all patients in group A and 50% of group B were operated on as "status one" patients. The total six-month mortality rate decreased from 69% before 1992 to 48% thereafter (p < 0.05). CONCLUSION: The short-term prognosis of patients with refractory heart failure improved over time. In the latter period, ACE-inhibitors were used more frequently and the number of heart transplantations was greater. Nevertheless, our results do not allow us to identify the causes of the improved survival rate.

[Coronary angioplasty in acute myocardial infarction]. / Angioplastica coronarica primaria nell'infarto miocardico acuto.

Primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) allows to obtain a higher reperfusion rate in the culprit vessel than thrombolytic therapy, reducing the incidence of death, non fatal reinfarction and recurrent ischemia. The aim of this study was to test the in-hospital and mid-term results of an early invasive strategy with PTCA in patients with AMI. Thirty-four patients with AMI underwent coronary angiography within 3 hours from the onset of symptoms. Twenty-four patients had anterior AMI and 3 were in cardiogenic shock. Three patients, 1 without significant lesions and 2 with multivessel diffuse coronary disease, were left out of the procedure, and 31 patients underwent PTCA. Twenty-six lesions were total occlusions with TIMI flow 0.A TIMI flow 1 was present in the other 5 vessels. Stent deployment was decided for 16 lesions (52%). Primary success (TIMI flow 3 with mean residual stenosis of 15 +/- 20%) was obtained in 30 patients (97%). In 1 patient recanalization of the anterior descending coronary artery was not possible due to tortuosity of the abdominal and thoracic aorta. At pre-discharge angiography a good result was confirmed in 24/25 patients. After 6 months only 1 patient (3%) underwent a new PTCA for recurrent angina. In conclusion, primary PTCA for AMI within 3 hours of symptom onset allows good in-hospital and mid-term results with a low rate of complications.

Troponin T, creatine kinase MB mass, and creatine kinase MB isoform ratio in the detection of myocardial damage during non-surgical coronary revascularization.

The presence of myocardial injury during non-surgical coronary revascularization has been evaluated by means of highly specific and sensitive biochemical markers. Troponin T, creatine kinase-MB isoenzyme mass concentration, and creatine kinase MB2/MB1 isoform ratio have been determined in 80 patients who underwent coronary revascularization with percutaneous transluminal coronary angioplasty (PTCA). Forty-five patients underwent balloon angioplasty, 15 rotational atherectomy, 10 directional atherectomy, and 10 elective coronary stenting. Serum concentration of the evaluated markers did not increase significantly after 57 uncomplicated revascularization procedures, including 15 rotablation procedures, nor after 8 PTCAs complicated by localized coronary type B and C dissections. Significant elevation of all markers above the upper limits of the reference interval (P < 0.05) was detected after occlusion of small side branches (< 0.5 mm diameter) in 5 patients. Creatine kinase MB2/MB1 isoform ratio was the earliest marker to increase. After recanalization of occluded vessels in 8/10 patients with 6-60 days old myocardial infarction only troponin T concentrations increased from a baseline of 0.28 microgram/l to a median peak of 0.80 microgram/l. This increase was statistically not significant (P = 0.12). In conclusion, myocardial damage was not detected following uncomplicated non-surgical revascularization obtained with different techniques. Markers of myocardial injury provide high sensitivity after small side branch occlusion.

[Indications for heart transplant: retrospective evaluation of criteria for selection of candidates]. / Indicazioni al trapianto cardiaco: valutazione retrospettiva dei criteri di selezione dei candidati.

INTRODUCTION: Heart transplantation (HT) is a largerly accepted therapy for patients with refractory congestive heart failure. However, lack of donors imposes a rigorous choice among candidates for transplantation. Aim of this study was to identify retrospectively determinants for the selection of recipients. METHODS: Between december 1985 and december 1993 500 patients were listed for HT at the Department of Cardiovascular Surgery of the Padua University. Among United Network for Organ Sharing (UNOS) status II patients, 42 transplanted (group I) and 38 died waiting for a donor (group II) were chosen. The following parameters were collected at the time of insertion into the waiting list: sex, blood group, diagnosis, age, body surface area, natriemia, renal function, hepatic function, presence of ventricular arrhythmias, use of ACE-inhibitors, cardiac index, mean pulmonary pressure, mean wedge pressure, mean arterial pressure, central venous pressure, pulmonary arteriolar resistances, left ventricular ejection fraction. Also the time on waiting list until a final event (transplantation or death) was considered. RESULTS: Comparing the two groups the diagnosis of dilated cardiomyopathy (59.4% group I vs 36.8% group II; p = 0.04) and ejection fraction (26.4 +/- 9.1% group I vs 22.2 +/- 8.0% group II; p = 0.03) were the only variables statistically different. Multivaried analysis evidenced some parameters as independent predictors for HT. In detail, being listed for HT for more than 6 months lowered the probability to receive a heart to 0.34, while waiting for more than 12 months increased it to 2.64. Mean arterial pressure higher than 75 mmHg increased the probability for HT to 2.87, while an increase in mean pulmonary pressure of 5 mmHg lowered the probability to 0.80. An increase in the cardiac index of 0.5 l/m1/m2 lowered the probability to 0.61. A blood group other than 0 increased the possibility to 3.60, the basal surface area higher than 1.78 m2 lowered it to 0.306 and an ejection fraction higher than 22% increased it to 3.94. CONCLUSIONS: We can conclude that parameters which predict the outcome of patients listed for HT were not only size matching, blood group and waiting time, but also ejection fraction, arterial pressure and diagnosis.

Percutaneous transluminal coronary angioplasty in refractory unstable angina pectoris: are new devices useful?

This study was undertaken to assess if the introduction of new angioplasty devices (autoperfusion balloon catheters, stent and atherectomy) could ameliorate early and late results of prompt percutaneous transluminal coronary angioplasty (PTCA) in patients with refractory unstable angina. From January 1993 to June 1995, 59 of 278 patients (14 female, 45 male; mean age: 61 +/- 10 years; range: 38-78) admitted to our Coronary Care Unit with the diagnosis of unstable angina had more than one episode of chest pain at rest with dynamic electrocardiographic ST-T changes and without signs of cardiac necrosis while on medical therapy including oxygen, aspirin, heparin, nitroglycerin and either a beta-blocker or a calcium-antagonist. Coronary angiography was performed within 48 h from the last ischemic attack and a culprilesion technically suitable for PTCA was identified. PTCA was performed in 73 lesions. Elective stent implantation was considered for 16 type B or C lesions in 14 patients. The procedure was initially successful in 52/59 patients (88%), uncomplicated unsuccessful in 4/59 (7%) and complicated in 3/59 (5%). Elective stent insertions were all successful (16/16, 100%). All successfully treated patients were followed up for a mean of 12 +/- 7 months (range: 6-27): 2/52 patients (3.8%) suffered from non-transmural myocardial infarction, 14/52 (26.9%) had a recurrence of angina and 2/52 (3.8%), asymptomatic, had a positive stress test. We conclude that prompt PTCA in refractory unstable angina using 1990s 'state of the art' equipment compares favorably to previous study and that stent delivery might become the elective treatment of complex lesions in this subset of patients.

[Analysis of risk factors in a group of patients referred for heart transplantation for refractory heart failure: multivariate analysis]. / Analisi dei fattori di rischio in un gruppo di soggetti riferiti per trapianto cardiaco a causa di uno scompenso cardiaco refrattario: analisi multivariata.

BACKGROUND: In the absence of evident clinical controindication heart transplantation can be performed in patients with critical degree of cardiac failure. The choice of adequate candidates for transplantation is frequently based on clinical severness but also influenced by factors as body size, blood group and so on. METHODS: To identify the presence of prognostic factors for patients with high risk of death, clinical, hemodynamic and therapeutic features of 70 patients (mean age 44.8 +/- 13.8) with critical cardiac failure (64 patients in IV class N.Y.H.A.) have been reviewed. Most of them were affected by dilated or ischemic cardiomyopathy. RESULTS: All patients were admitted to Cardiac Intensive Care Unit, 13 patients received transplantation, 24 were discharged and 33 died. Univariate analysis evidenced, that in the group of patients who died, sepsis (p = 0.0003), renal (p = 0.04) and liver function impairment (P = 0.007) occurred significantly more frequent. The differentiated use of catecholamines (P = 0.0007) and of vasodilators (P = 0.007), the need of mechanical ventilation (P = 0.0001) and the need of hemodialysis (P = 0.02) resulted significantly higher in the group of dead patients where mean arterial pressure (p = 0.01) and mean systemic resistances (P = 0.04) resulted significantly lower. With multivariate analysis were identified following independent risk factors of death: male sex, infections, mechanical ventilation, differentiated use of vasodilators, mean arterial pressure and mean pressure in pulmonary artery. CONCLUSIONS: As predictive risk factors of death in patients with critical cardiac failure and awaiting transplantation resulted: sex, the presence of infection, mechanical ventilation and differentiated use of vasodilators whereas hemodynamic parameters did not result of important predictive value.

[The efficacy and safety of slow-release nicardipine vs nifedipine in angina]. / Efficacia e tollerabilità della nicardipina a lenta liberazione vs nifedipina nell'angina.

This controlled, double-blind, completely randomized study assessed the efficacy and safety of nicardipine and nifedipine, both in slow-release formulations, in patients with unstable angina. Thirty patients (28 M, 2F) were included in the final analysis, mean age 56.5 +/- 9.1 years (SD), mean weight 73.5 +/- 9.2 kg, mean height 171.5 +/- 6.5 cm, all with unstable angina. Nicardipine was given at a daily dosage of 80-120 mg, and nifedipine 40-60 mg, for up to one month. At the end of treatment with nicardipine supine systolic and diastolic blood pressure (SBP and DBP) dropped respectively 7.7% and 5.5% at 8 am and 8.6% and 7.1% at 8 pm. Nifedipine reduced SBP and DBP by respectively 6.5% and 13.1% at 8 am and 5.3% and 9.4% at 8 pm. There was no clinical or statistical difference between the treatments. Heart rate did not change appreciably during either treatment. On completion of nicardipine treatment, 87.5% of patients had suffered no angina attacks, compared with 66.7% for nifedipine. The remaining 12.5% of patients treated with nicardipine presented only one mild angina attack per day, while the other 33.3% of the nifedipine patients had one moderate angina attack per day. No untoward effects were reported with nicardipine; one patient receiving nifedipine presented cardiopalmus and another complained of headache. These results indicate that nicardipine is at least as safe and effective as nifedipine in the treatment of unstable angina.

Production of mouse monoclonal antibodies using a continuous cell culture fermenter and protein G affinity chromatography.

The production of anti-alpha-fetoprotein monoclonal antibodies for diagnostic use was carried out in a stirred tank fermenter equipped with a double membrane stirrer for bubble free aeration and continuous medium perfusion. A serum-free medium supplemented with 4 mM L-glutamine and 2.0 milligrams glucose with a protein content of only 780 micrograms/ml was used for the production process. The harvested antibodies were concentrated 50-fold using a tangential ultrafiltration system and were then purified in a one step purification process by protein G affinity chromatography. The purity of the final product (90%) was controlled by SDS-polyacrylamide gel electrophoresis, gel exclusion chromatography and isoelectric focussing. For further quality controls of the product the immunoglobulin subclass and the isoelectric point were determined and the specificity of the purified mAb was tested by RIA using 125I labelled alpha-fetoprotein. 1.87 g of purified monoclonal antibodies were produced (90% purity) within 2 weeks. It was found that the use of this type of stirred tank fermenter combined with a one step purification process using protein G affinity chromatography represents a suitable method for the fast production of medium scale quantities (500 mg-5 g) of monoclonal antibodies for diagnostic use.

[Persistent T-wave inversion in unstable angina: the correlation with the global and regional function of the left ventricle]. / Inversione persistente dell'onda T nell'angina instabile: correlazione con la funzione globale e regionale del ventricolo sinistro.

The correlation between persistent negative T wave on basal electrocardiogram and coronary anatomy or global and regional left ventricular function was investigated in 34 patients with unstable angina defined as new onset (< 2 months), crescendo or rest angina. The patients with history of previous myocardial infarction, pathological Q waves on electrocardiogram or documented elevation of CPK were excluded. Eighteen patients (group A) showed T wave inversion (> 1 mV) in at least two leads on the basal electrocardiogram, persisting for at least 48 hours before coronary arteriography. In 16 patients (group B) the basal electrocardiogram was normal. Left ventricular volumes and ejection fraction were calculated and the regional systolic wall motion was analyzed using the area method in the 30 degrees right anterior oblique view. Hypokinesis was defined as more than 2 standard deviation below the mean value calculated in 24 normal subjects. No difference was present for age (A: 61 +/- 9 vs B: 57 +/- 9 yrs) and sex distribution. Critical stenoses of at least one coronary artery was documented in all but one patient (in group B). The number of critical stenosis per patient was equal (1.8) in the two groups. Left main coronary artery showed narrowing > 50% in three patients of group A and in two patients of group B.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of a monocyte chemotactic cytokine by human mononuclear phagocytes.

The present study was designed to investigate the capacity of human mononuclear phagocytes to produce a cytokine chemotactic for monocytes (monocyte chemotactic protein (MCP), alternative acronyms JE, monocyte chemotactic and activating factor, MCP-1, and tumor-derived chemotactic factor). Human PBMC exposed in vitro to bacterial LPS expressed high levels of MCP transcripts. Monocyte-depleted lymphoid cells were not induced to express MCP by LPS. Percoll-gradient purified monocytes were able to express high levels of MCP transcripts. In an effort to exclude a role of contaminating non-monocytic cells, mononuclear phagocytes were separated by flow cytometry and sorting: CD14+ cells exposed to LPS showed high levels of MCP mRNA. LPS-stimulated monocytes released chemotactic activity for monocytes that could be inhibited by absorption with anti-MCP antibodies. IL-1, TNF, IFN-gamma, granulocyte-macrophage-CSF and, to a lesser extent, macrophage-CSF, as well as inactivated streptococci, also induced MCP gene expression. Actinomycin D experiments indicated that induction of MCP in monocytes was gene transcription-dependent. The protein synthesis inhibitor cycloheximide (Cy) blocked IL-1-, TNF-, or LPS-induced MCP gene expression in monocytes. In contrast, expression of the structurally related chemotactic cytokine IL-8 was superinduced by Cy. Moreover, Cy superinduced MCP gene expression in cells other than monocytes, including endothelial cells, smooth muscle cell and fibrosarcoma cells, indicating different mechanisms of regulation in mononuclear phagocytes vs cells of other lineages. The capacity of cells of the monocyte-macrophage lineage to produce a cytokine that recruits and activates circulating monocytes may be of considerable importance in inflammatory and immunologic reactions. Thus, the mononuclear phagocyte system can autonomously regulate the extravasation and activation of immature elements of the same lineage, a key event in inflammation and immunity.

Interleukin 4 amplifies monocyte chemotactic protein and interleukin 6 production by endothelial cells.

Upon exposure to interleukin 4 (IL-4), human umbilical vein endothelial cells (EC) produced low amounts of IL-6 and expressed low levels of IL-6 transcripts. While being a weak stimulus for IL-6 production, IL-4 amplified the release and mRNA expression of this cytokine in response to optimal concentrations of IL-1. IL-4 also induced low levels of monocyte chemotactic protein but amplified the expression of this chemoattractant in response to inflammatory signals. Thus IL-4, by amplifying at the level of the vascular endothelium the expression of vascular cell adhesion molecule 1 selectively, as well as that of chemoattractants and IL-6, may favour the selective recruitment and activation of lymphoid and monocytic elements crucial for subacute/chronic inflammation and immune reactions.

[Thrombosis on a mitral valve prosthesis: treatment with urokinase and color-Doppler monitoring]. / Trombosi su protesi valvolare mitralica: trattamento con urokinasi e monitorizzazione con color-Doppler.

A case of thrombolytic treatment with urokinase on a Sorin mitral prosthesis is described. Thrombolytic therapy, that is an alternative to valvular replacement was effective. Color-Doppler showed as a reliable method to monitor therapy effectiveness. However, a serious complication was cerebral embolism.

Unexpected sudden death during acute myocardial infarction: role of primary electromechanical dissociation.

The causes of death during the acute phase of myocardial infarction were studied in 128 patients. Forty-three of these, who had no clear signs of cardiocirculatory failure, were considered to be cases of sudden and unexpected death. Thirty-two of these patients (74%) had electromechanical dissociation, defined as a sudden disappearance of an effective arterial pressure in the presence of adequate electrocardiographic complexes. Twenty-three patients who had been given this diagnosis were males and 9 females; 53% presented with anterior infarction, 31% with infero-posterior infarction, 3.5% with both anterior and infero-posterior and 12.5% with non-Q wave infarction. A previous episode of infarction was recorded in 31.2% of patients with electromechanical dissociation. Autopsy was performed in 84 patients, 23 of whom died with electromechanical dissociation. Half of the latter cases revealed cardiac rupture (secondary electromechanical dissociation), whereas in the other half death was due to primary electromechanical dissociation. The study stresses the relatively high incidence of this cause of death and the need to differentiate between the two different forms. Although at present the pathophysiology of primary electromechanical dissociation is not completely understood, we believe that recurrence of global or local ischemia may play a more important role than cardiovascular inhibitory reflexes.