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Biomedical subjects

M Pini

Publications and source records attributed to M Pini.

At least 19 recordsLinked to original sources
PubMed2004

Tensile and compressive behaviour of the bovine periodontal ligament.

The mechanical response of the bovine periodontal ligament (PDL) subjected to uniaxial tension and compression is reported. Several sections normal to the longitudinal axis of bovine incisors and molars were extracted from different depths. Specimens with dimensions 10 x 5 x 2 mm including dentine, PDL and alveolar bone were obtained from these sections. Scanning electron microscopy suggested a strong similarity between the bovine PDL and the human PDL microstructure described in the literature. The prepared specimens were tested in a custom made uniaxial testing machine. They were clamped on their bone and dentine extremities and immersed in a saline solution at 37 degrees C. Stress-strain curves indicated that the PDL is characterized by a non-linear and time-dependent mechanical behaviour with the typical features of collagenous soft tissues. The curves exhibited hysteresis and preconditioning effects. The mechanical parameters evaluated in tension were maximum tangent modulus, strength, maximizer strain and strain energy density. For the molars, all these parameters increased with depth except for the apical region. For the incisors, all parameters increased with depth except ultimate strain which decreased. It was assumed that collagen fibre density and orientation were responsible for these findings.

Adaptation, Physiological↗
PubMed2003

Low-molecular-weight heparin for the long-term treatment of symptomatic venous thromboembolism: meta-analysis of the randomized comparisons with oral anticoagulants.

BACKGROUND: The management of venous thromboembolism (VTE) requires an initial treatment with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH), followed by oral anticoagulants (OA) for at least 3 months. OA treatment however, requires laboratory monitoring of anticoagulation, carries a definite risk of bleeding, and may be contraindicated in some patients. As an alternative to vitamin K antagonists, subcutaneous LMWH has been proposed and evaluated in randomized clinical trials, but they are all small studies that lack the power to establish if these two treatment modalities are equivalent in efficacy or safety. OBJECTIVES: The objective of this review was to evaluate the efficacy (VTE recurrence) and safety (bleeds and deaths) of long-term treatment of VTE with LMWH compared with OA. A secondary endpoint was to evaluate the effect of LMWH on cancer mortality. METHODS: Computerized searches of MedLine and EmBase were performed. In addition, randomized clinical trials were located through personal communication with colleagues, and through the manual scanning of meeting proceedings and reference lists of relevant studies. When necessary, the authors of the selected papers were called to obtain additional information. Two reviewers (AI and FG) reviewed and extracted data independently using a standard form. The primary analysis was performed for efficacy and safety endpoints on an intention-to-treat basis for the study period of randomized treatment. A meta-regression analysis was used to investigate the relationship between daily dose and clinical outcome. RESULTS: Seven studies that fulfillled our predefined criteria were identified, for a total of 1379 patients. When all studies were combined, a statistically non-significant reduction in the risk of VTE (OR 0.66; 95% confidence interval [CI] 0.41, 1.07) and in the risk of major bleeding (OR 0.45; 95% CI 0.18, 1.11) in favor of LMWH treatment was found. No difference in total mortality (OR 1.19; 95% CI 0.78, 1.83) or in cancer-related mortality was observed between the LMWH and the OA treatment. CONCLUSIONS: The results of this meta-analysis indicate that a 3-month course of LMWH is as effective and safe as a corresponding period of OA treatment, and may thus be considered as a valuable alternative option for patients in whom OA treatment appears contraindicated or problematic.

Anticoagulants↗
PubMed2002

Mechanical characterization of bovine periodontal ligament.

This study is part of a research program that aims to develop a constitutive three-dimensional model of the periodontal ligament (PDL) through the identification of pertinent material parameters. As part of this program, bovine PDL was utilized to establish stress-strain responses under tensile and compressive loading conditions. Fresh bovine molars were secured, frozen and prepared to appropriate dimensional specifications. Bar-shaped specimens that comprised portions of dentine, PDL and bone were produced. Push-pull tests were conducted using a specifically constructed loading machine. Full range monotonic stress-strain diagrams were generated. The effect of a rate increase on cyclic S-E diagrams was also determined. The influence of specimen thickness was expressed in terms of modulus of elasticity, strength, uniaxial maximizer strain, and strain energy density. The overall load-response was heavily hysteretic in compression. On the tensile side, after a steep rise, the curve tended to flatten out asymptotically. Variations in rate that spanned four orders of magnitude had no effect on reciprocal load responses. The E-modulus was in the 4-8 MPa range, the strength of the PDL was 1-2 MPa, the maximizer strain was at 45-60% and the strain energy density ranged between 0.3 and 0.4 MPa.

Alveolar Process↗
PubMed2001

Loco-regional thrombolysis in the treatment of cerebral venous and sinus thrombosis: report of two cases.

Although intravenous (i.v.) heparin is widely used as the first line treatment for cerebral venous and sinus thrombosis (CVST), the most appropriate therapy for this disease is still controversial. We report 2 cases of CVST who were successfully treated by means of loco-regional thrombolysis with urokinase. In the first case we chose this treatment instead of i.v. heparin because clinical conditions of the patient appeared critical for life on hospital admission; in the second case loco-regional thrombolysis was performed because a full-dose heparin treatment over 8 days failed to improve the clinical picture of the patient. In the literature, there are no established criteria for the use of loco-regional thrombolysis in CVST. On the basis of our own experience and few previous reports on the matter, we suggest that loco-regional thrombolysis should be considered an appropriate treatment for CVST when patients are at life risk, when an involvement of deep cerebral veins is present or when, after full heparinization, patients are doing poorly clinically.

Cerebral Angiography↗
PubMed2000

Fracture toughness of aged dental composites in combined mode I and mode II loading.

Resin-based laboratory dental composites for prosthetic restorations have been developed in the past years as a cost-effective alternative to conventional porcelain-fused-to-metal or full ceramic restorations. The fracture toughness at different stress states (K(Ic), K(IIc), and mixed-modes K(I), K(II) ) was assessed for three laboratory dental composite resins used for prosthetic restorations that were aged up to 12 months in a food simulating fluid (10% ethanol) at 37 degrees C. The materials were mainly di- methacrylate based resins reinforced with submicron glass filler particles. The Brazilian disk test was used on precracked chevron-notched specimens, and different stress states were obtained by angulating the precracked chevron notch relative to the diametral compressive loading direction. The stress intensity factors were calculated using Atkinson et al.'s relation. For all three materials, mode I fracture toughness values ranged between 0.48-0.64 MPa. m(0.5) and mode II values ranged between 0.93-1.2 MPa. m(0.5). Overall, aging time and storage media had little effect on toughness. Considering the inherently low toughness of these restorative materials, their use should be limited to low stress masticatory areas.

Aluminum Oxide↗
PubMed2000

Field dependence and verbalized strategies on the portable rod-and-frame test by depressed outpatients and normal controls.

This study examined the relationships between scores on the cognitive style of field dependence-independence and verbalized strategies on the Portable Rod-and-Frame Test for normal and psychopathological outpatients. We attempted to verify (a) Manning's hypothesis (1991) of a correspondence between scores on field dependence and external strategies (reference to the visual field) and scores on field independence and internal strategies (reference to the body) on perceptual tasks, and (b) a tendency of depressed persons to score as field dependent, and (c) use of external verbalized strategies. A total of 50 depressed outpatients and 50 normal controls were administered the test and requested to report the strategy they had employed to solve the problem. Contrary to Manning's findings, no significant relationship was found between cognitive style and verbalized strategies in the total sample. Depressed outpatients classified as internal scored significantly higher on the Group Embedded Figures Test but appeared more field dependent on the Rod-and-Frame Test. Moreover, only for the former test did depressed outpatients score more field-dependent than controls. Finally, no significant relationship was found between the diagnosis of depression and use of external strategies; however, field dependence and the use of external strategies on the Rod-and-Frame Test were associated with more severe depressive symptoms measured by the D scale of the MMPI-2. Further research is needed to assess the role of premorbid personality structures of depression in subjective and objective aspects of Rod-and-Frame Test performance.

Adult↗
PubMed1999

Low-oestrogen oral contraceptives as a major risk factor for cerebral venous and sinus thrombosis: evidence from a clinical series.

Cerebral venous and sinus thrombosis (CVST) is still considered a severe clinical problem that is difficult to diagnose and manage and is linked to a poor prognosis. Nonetheless, conventional cerebral angiography and magnetic resonance imaging (MRI), or more recently, MR angiography allow a more rapid and precise diagnosis, and prognosis has improved with the use of anticoagulant treatment. We report 23 cases of CVST consecutively admitted to the Institute of Neurology of the University of Parma during the period 1990-1997. In all cases diagnosis was confirmed by means of MRI or conventional angiography of brain vessels. Among the patients, 22 were female and 1 was male. In all patients, plasma levels of protein C, protein S, antithrombin III (ATIII) and antiphospholipid antibodies (APA) were evaluated. In 15 of 23 patients, the presence of factor V Leiden mutation was also determined, and found positive in 3 patients (20%). Of the 22 female patients, 15 (68%) were on low-oestrogen (containing less than 50 microg oestrogen) oral contraceptive (OC) treatment. This percentage of OC use by patients with CVST is much higher than that of the rest of the female Italian population. OC use was associated with the presence of factor V Leiden mutation in two cases, with a deficiency of protein C in 1 case and a deficiency of protein S in another.Whether low-oestrogen Ocs may induce cerebral thromboembolic events is an open matter. According to our data, it may be argued that Ocs, even if at low oestrogen content, represent a major risk factor for CVST. The use of Ocs, as is the case for systemic venous thromboembolic events, may further increase the risk of CVST in women carrying the factor V Leiden mutation or other inherited hyperthrombotic conditions.

Adult↗
PubMed1999

Diagnostic strategies in venous thromboembolism.

BACKGROUND AND OBJECTIVE: Diagnosis of acute deep vein thrombosis (DVT) and of pulmonary embolism (PE) is often difficult: symptomatic patients are usually investigated employing several diagnostic tests, which should be appropriately selected and sequenced, taking into account their sensitivity, specificity, safety and cost. The objective of this paper is to evaluate the performance of the new diagnostic tests and their combination in rational diagnostic strategies. DESIGN AND METHODS: A literature review was made using a Medline(R) database search for the period 1988-1998 on the following key words in various combinations: diagnosis, diagnostic strategy, venous thrombosis, pulmonary embolism, venous thromboembolism. Results of a new study by our group on diagnosis of DVT in hospitalized patients are also discussed. RESULTS: In patients with symptoms or signs suggestive of DVT, compression ultrasound (CUS) appears to be the diagnostic test of first choice, since it is a noninvasive test with high specificity and sensitivity for proximal DVT (about 97%). When CUS gives a negative result it is usually recommended that the test is repeated after one week, since its sensitivity for calf DVT is poor. The positive and negative predictive values (PPV and NPV) of CUS in symptomatic outpatients can be improved if adequate consideration is given to clinical diagnosis, using a standardized model (ref. #9), which allows symptomatic outpatients to be categorized as having a high, moderate or low probability of DVT. In case of agreement between clinical diagnosis and CUS results, no further testing is needed: patients with high or intermediate clinical probability and positive CUS results are treated, while in patients with low clinical probability and negative CUS results the diagnosis of DVT is excluded. In the case of discrepancy between clinical diagnosis and CUS results, D-dimer test and/or venography are requested. However in patients who develop signs or symptoms of DVT in the hospital the clinical model does not work, and diagnosis should be based on an appropriate mix of CUS, D-dimer (DD) test and venography. In patients presenting with signs or symptoms of pulmonary embolism, the ventilation/perfusion (V/P) lung scan remains a pivotal diagnostic test, and pulmonary angiography the reference standard, but both methods have limitations and in recent years other diagnostic tests such as echocardiography, helical (or spiral) computerized tomography, and magnetic resonance imaging have been introduced into clinical practice. Moreover, all four diagnostic tools mentioned for DVT diagnosis can be considered. Several diagnostic strategies have been proposed and evaluated in comparative studies but there is still debate over the most efficient test combination or sequence. INTERPRETATION AND CONCLUSIONS: Diagnostic strategies which include adequate consideration of clinical diagnosis using standardized models have the potential of being more efficient for outpatients (but not for inpatients) with symptoms or signs suggesting DVT of lower limbs. For patients with suspected PE, several diagnostic strategies have been assessed: V/P lung scan remains a pivotal diagnostic test, but its limitations have been increasingly recognized and newer non-invasive techniques are gaining credit. A consensus is still to be reached over the most appropriate combination of diagnostic tests.

Angiography↗
PubMed1999

Future prospects of prophylaxis for deep vein thrombosis.

The last decade has witnessed substantial progress in the prevention and treatment of venous thromboembolism. However, the risk of deep vein thrombosis remains high in trauma patients and those undergoing orthopaedic surgery despite use of the best available prophylaxis. Existing antithrombotics also carry a significant risk of bleeding and other adverse effects, including heparin-induced thrombocytopenia (HIT). More effective and safer anticoagulants are therefore needed. Current approaches for improving the benefit:risk ratio of antithrombotic therapy include the development of indirect thrombin inhibitors with a high anti-Xa:anti-IIa activity ratio, and the use of direct thrombin inhibitors. Novel indirect thrombin inhibitors under investigation include pentasaccharide and the heparinoid danaparoid. These agents may offer reduced bleeding risk compared with conventional therapies, but there is no evidence of greater antithrombotic efficacy. However, due to low cross-reactivity with anti-heparin-platelet factor 4 antibodies, danaparoid and pentasaccharide may prove valuable in the management of HIT. Theoretically, the antithrombotic effect of direct thrombin inhibitors may be greater than that of indirect inhibitors because direct inhibitors are not dependent on endogenous cofactors and are able to inhibit both free and clot-bound thrombin. Direct inhibitors of the active site of thrombin and recombinant variants of hirudin, originally derived from the medicinal leech, are currently under investigation. Early data on lepirudin and desirudin suggest that recombinant hirudins may have clinical applications in thromboprophylaxis for high-risk patients, acute cardiology indications and HIT.

Anticoagulants↗
PubMed1999

[Guidelines and clinical practice: anticoagulant therapy and cardioversion in atrial fibrillation].

UNLABELLED: The cardioversion of atrial fibrillation is linked to a substantial risk of systemic embolization. In an effort to reduce it, the American College of Chest Physicians (ACCP) periodically publishes guidelines for the use of anticoagulation in the conversion of atrial fibrillation. OBJECTIVE: Determination of the physician's compliance with the recommendations of the "Fourth ACCP Consensus Conference on Antithrombotic Therapy". METHODS: The charts of people admitted to a community hospital in 1998 with a diagnosis of atrial fibrillation (n = 202) were evaluated retrospectively. Consideration was given to the ACCP's recommendation to give anticoagulants 3 weeks before and 4 weeks after elective cardioversion to patients who had been in atrial fibrillation for more than 2 days. RESULTS: Ninety-one of the 202 patients admitted with atrial fibrillation reported the onset of arrhythmia more than 48 hours before. Thirty-four of them underwent elective cardioversion and 13 cases (33%) went without anticoagulation in the preceding 2 weeks. Of these 13 cases, 8 were patients aged over 75 (range 78-88, mean 84). After sinus rhythm had been restored in 30 people (spontaneously in 5 of them), the anticoagulant therapy was not administered during the 4 recommended weeks in 10 people (33%), all of them over 75 (range 77.94, mean 84). CONCLUSIONS: Anticoagulation for cardioversion of atrial fibrillation is underused, especially among elderly patients. In order not to let age itself be an obstacle to the correct treatment of patients with high embolic risk, our efforts must be improved in order to identify the correct therapeutic choice in each particular case. Initiatives aimed at identifying and removing any impediment to the application of guidelines may contribute to stimulating physicians in the process of evaluating the quality of hospital treatment.

Adult↗
PubMed1998

Enoxaparin plus compression stockings compared with compression stockings alone in the prevention of venous thromboembolism after elective neurosurgery.

BACKGROUND: Compression stockings are recommended for prophylaxis against venous thromboembolism in patients undergoing neurosurgery, but anticoagulant agents have not gained wide acceptance because of concern about intracranial bleeding. METHODS: In a multicenter, randomized, double-blind trial, we assessed the efficacy and safety of enoxaparin in conjunction with the use of compression stockings in the prevention of venous thromboembolism in patients undergoing elective neurosurgery. Enoxaparin (40 mg once daily) or placebo was given subcutaneously for not less than seven days beginning within 24 hours after the completion of surgery. The primary end point was symptomatic, objectively confirmed venous thromboembolism or deep-vein thrombosis assessed by bilateral venography, which was performed in all patients on day 8+/-1. Bleeding side effects were carefully assessed. RESULTS: Among the 307 patients assigned to treatment groups, 129 of the 154 patients receiving placebo (84 percent) and 130 of the 153 patients receiving enoxaparin (85 percent) had venographic studies adequate for analysis. An additional patient in the placebo group died before venography of autopsy-confirmed pulmonary embolism. In this analysis, 42 patients given placebo (32 percent) and 22 patients given enoxaparin (17 percent) had deep-vein thrombosis (relative risk in the enoxaparin group, 0.52; 95 percent confidence interval, 0.33 to 0.82; P=0.004). The rates of proximal deep-vein thrombosis were 13 percent in patients receiving placebo and 5 percent in patients receiving enoxaparin (relative risk in the enoxaparin group, 0.41; 95 percent confidence interval, 0.17 to 0.95; P=0.04). Two patients in the placebo group died of autopsy-confirmed pulmonary embolism on days 9 and 16. Major bleeding occurred in four patients receiving placebo (intracranial bleeding in all four) and four patients (intracranial bleeding in three) receiving enoxaparin (3 percent of each group). CONCLUSIONS: Enoxaparin combined with compression stockings is more effective than compression stockings alone for the prevention of venous thromboembolism after elective neurosurgery and does not cause excessive bleeding.

Adult↗
PubMed1998

Risk of acute cerebrovascular events related to low oestrogen oral contraceptive treatment.

To establish if an association exists between use of oral contraceptives (OC) and the occurrence of cerebral arterial thromboembolism, cerebral venous thrombosis and retinal vein/artery thrombosis, we identified all women aged 15-44 years resident in the province of Parma, Italy, who were hospitalized because of a documented cerebral or retinal thromboembolic event during the period 1989-1993. The numbers of users and nonusers of OC were estimated from drug sale data and demographic statistics for the province. There were 21 cases of cerebral arterial thromboembolism during the study period: 10 in OC users and 11 in nonusers, for an estimated incidence rate of 1.70 and 0.35 per 10,000 woman-years OC of use and nonuse, respectively (RR=4.8, 95% CI = 1.8-9.0). Eight cases of cerebral venous thrombosis were observed: 6 in OC users and 2 in nonusers (both in puerperium), for an incidence rate of 1.00 and 0.06 per 10,000 woman-years, respectively (RR=16.7, 95% CI = 3.3-81.4). Finally, 13 cases of retinal vein/artery thrombosis were found: 1 in OC users and 12 in nonusers, for an incidence rate of 0.17 and 0.37 per 10,000 woman-years, respectively (RR=0.46, 95% CI = 0.06-3.7). In our population study the use of low oestrogen OC was associated with an increased risk of cerebral venous thrombosis and ischemic stroke, but not of retinal vein/artery thrombosis.

Acute Disease↗
PubMed1997

Prevention of recurrences after deep venous thrombosis: role of low-molecular-weight heparins.

The management of deep venous thrombosis (DVT) requires an initial treatment with unfractionated (UF) or low-molecular-weight (LMW) heparin followed by oral anticoagulants (OA) for at least 3 months. OA therapy, however, requires laboratory monitoring and is associated with a definite bleeding risk. Therefore, alternative treatments such as UF or LMW heparin have been evaluated. In a study by Monreal et al in patients with DVT and contraindications to OA, dalteparin (5000 anti-Xa U b.i.d.) was equivalent to UF heparin (10,000 IU b.i.d.) and was associated with fewer vertebral fractures. In a study by Pini et al, Enoxaparin (4000 anti-Xa U once daily) was evaluated against OA and showed similar efficacy with fewer bleeding complications in the 3-month treatment period. A number of studies have recently shown that the risk for late thrombotic recurrences for patients developing postoperative DVT or associated with other transient risk factors is much lower than in patients with idiopathic DVT or associated with a persistent risk factor, suggesting that for the formers, 4 to 6 weeks of OA therapy may be sufficient. LMW heparins appear to be a promising alternative therapy for these patients, because in the first month of OA administration the risk for bleeding is higher and the need of laboratory monitoring more stringent. This should be evaluated in appropriate clinical trials.

Administration, Oral↗
PubMed1997

[Low molecular weight heparin].

Low-molecular-weight heparins (LMWHs) are obtained by depolymerization from standard heparin and show substantial advantages compared with the parent compound, by virtue of their different pharmacokinetics and lower interaction with platelets, so that they are supplanting heparin in various clinical indications. In the prophylaxis of venous thromboembolism, LMWHs are more efficacious than unfractionated heparin in patients at high thrombotic risk, and equally efficacious in patients at moderate thrombotic risk, with the benefit of once-a-day administration. In the treatment of acute deep venous thrombosis and pulmonary embolism, LMWHs administered subcutaneously in fixed dose per kg of body weight show equivalent efficacy and safety than intravenous heparin in adjusted dose, and allow home treatment in selected cases. In the treatment of deep venous thrombosis after the acute phase, LMWHs are equally effective and safer than oral anticoagulants. In unstable angina and non Q myocardial infarction, nadroparine and enoxaparin plus aspirin have been shown to be more efficacious than unfractionated heparin plus aspirin. In acute ischemic stroke, preliminary results are promising, but the evidence of efficacy must be substantiated by other studies, which are currently in progress.

Adult↗
PubMed1996

The treatment of elderly patients with aggressive non-Hodgkin's lymphomas: feasibility and efficacy of an intensive multidrug regimen.

The results of a prospective trial of an 8 week treatment for elderly patients with advanced intermediate-high grade NHL are reported. Our aim was to reduce general toxicity without losing an antilymphoma effect. For this reason the use of growth factor was studied. We also analysed the behavior of different histological groups (E + F vs G + H). From November 1991 to November 1993 100 patients older than 65 years with combination intermediate-high grade advanced stage NHL were treated with the P-VEBEC regimen, an original including epirubicin 50 mg/sqm, cyclophosphamide 300 mg/sqm and etoposide 100 mg/sqm on weeks 1, 3, 5, 7; vinblastine 5 mg/sqm and bleomycin 5 mg/sqm on weeks 2, 4, 6, 8; prednisone 50 mg/sqm/day per os in the first two weeks and thereafter every other day .46 pts received rG-CSF 5 micrograms/Kg/day throughout the treatment starting on day 2 of every week for 4 consecutive days. Twenty eight pts had B symptoms, 41 had bulky disease, 37 LDH levels above normal, 50 stage IV patients and 30 had bone marrow involvement. Sixty two percent achieved a complete remission (CR). Adverse prognostic factors for CR were E and F histology, stage IV disease, bone marrow infiltration, serum LDH levels above normal, international Prognostic Index (I.I.) intermediate-high and high risk categories and relative dose intensity (RDI) less than 0.80. Severe toxicity was rarely recorded and only one toxic death was observed. With a median follow-up of 33 months OS, DFS and EFS were 44%, 60% and 30% respectively. EFS was influenced by stage, BM involvement, level of LDH and I.I. intermediate-high and high risks. The 52 patients with DLCL (diffuse large cell lymphomas--G + H according to WF) did better with a higher CR, OS, DFS and EFS rates, than the other WF subtypes. In conclusion P-VEBEC is a feasible combination to use in elderly patients, mainly in DLCL. The use of rG-CSF improves the RDI. A RDI > 0.80 could play a role in improving the outcome, especially in patients with adverse prognostic factors. For other subgroups another schedule is probably justified.

Aged↗
PubMed1994

Cytokine gene expression in B-cell chronic lymphocytic leukemia: evidence of constitutive interleukin-8 (IL-8) mRNA expression and secretion of biologically active IL-8 protein.

To extent our knowledge on the cytokines possibly involved in the pathophysiology of B-cell chronic lymphocytic leukemia (B-CLL), the mRNA expression of a panel of 10 cytokines was investigated on purified B-CLL cells using a reverse-transcriptase polymerase chain reaction method. Whereas negative RT-PCR signals were recorded for interleukin-1 alpha (IL-1 alpha), IL-2, IL-3, IL-4, IL-5, IL-7, tumor necrosis factor beta (TNF beta), and granulocyte-macrophage colony-stimulating factor, we detected the expression of IL-1 beta, IL-6 and TNF alpha. Furthermore, the constitutive expression of IL-8 mRNA was observed in all 17 B-CLL samples analyzed. mRNA expression was associated with the capacity of the leukemic cells to release IL-8 both constitutively (4.6 +/- 8.1 SD ng/mL) and, to a further extent, after stimulation (14.5 +/- 19.4 ng/mL). The circulating levels of IL-8 were also evaluated in 12 untreated B-CLL sera samples and the overall mean level was significantly higher (P < .01) than in normal sera. In addition, supernatants of purified B-CLL cells cultured in the presence of 12-O-tetradecanoylphorbol-13-acetate showed chemotactic activity towards neutrophils; this activity was neutralized in the presence of an anti-IL-8 antiserum. The mRNA for IL-8 was absent in five B-cell preparations from hairy cell leukemia cases and in four B-cell lines. Normal tonsil CD5+ B cells showed a low expression of IL-8 mRNA only in two of the nine preparations tested and the overall quantity of IL-8 released by these cells after 3 days' incubation was significantly lower compared with that released by B-CLL cells (0.4 +/- 0.3 and 1.6 +/- 0.9 ng/mL under basal and stimulated conditions, respectively). These findings point to an involvement of a member of the proinflammatory chemokine supergene family in human CD5+ B lymphocytes. The different IL-8 behavior observed between B-CLL cells and their normal counterpart is likely to reflect an activation state of the leukemic population.

Antigens, CD↗