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2.
J Thromb Haemost ; 2(6): 884-9, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15140122

ABSTRACT

Patients with symptomatic idiopathic venous thromboembolism and apparently cancer-free have an approximate 10% incidence of subsequent cancer. Apparently cancer-free patients with acute idiopathic venous thromboembolism were randomized to either the strategy of extensive screening for occult cancer or to no further testing. Patients had a 2-year follow-up period. Of the 201 patients, 99 were allocated to the extensive screening group and 102 to the control group. In 13 (13.1%) patients, the extensive screening identified occult cancer. In the extensive screening group, a single (1.0%) malignancy became apparent during follow-up, whereas in the control group a total of 10 (9.8%) malignancies became symptomatic [relative risk, 9.7 (95% CI, 1.3-36.8; P < 0.01]. Overall, malignancies identified in the extensive screening group were at an earlier stage and the mean delay to diagnosis was reduced from 11.6 to 1.0 months (P < 0.001). Cancer-related mortality during the 2 years follow-up period occurred in two (2.0%) of the 99 patients of the extensive screening group vs. four (3.9%) of the 102 control patients [absolute difference, 1.9% (95% CI, -5.5-10.9)]. Although early detection of occult cancers may be associated with improved treatment possibilities, it is uncertain whether this improves the prognosis.


Subject(s)
Mass Screening/methods , Neoplasms/diagnosis , Thromboembolism/etiology , Venous Thrombosis/etiology , Adult , Aged , Aged, 80 and over , Early Diagnosis , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasms/complications , Neoplasms/mortality , Prognosis , Treatment Outcome
3.
N Engl J Med ; 345(3): 165-9, 2001 Jul 19.
Article in English | MEDLINE | ID: mdl-11463010

ABSTRACT

BACKGROUND: In patients with idiopathic deep venous thrombosis, continuing anticoagulant therapy beyond three months is associated with a reduced incidence of recurrent thrombosis during the period of therapy. Whether this benefit persists after anticoagulant therapy is discontinued is controversial. METHODS: Patients with a first episode of idiopathic proximal deep venous thrombosis who had completed three months of oral anticoagulant therapy (with warfarin, in 97 percent of the cases and acenocoumarol in 3 percent) were randomly assigned to the discontinuation of oral anticoagulants or to their continuation for nine additional months. The primary study outcome was recurrence of symptomatic, objectively confirmed venous thromboembolism during at least two years of follow-up. RESULTS: The primary intention-to-treat analysis showed that of 134 patients assigned to continued oral anticoagulant therapy, 21 had a recurrence of venous thromboembolism (15.7 percent; average follow-up, 37.8 months), as compared with 21 of 133 patients assigned to the discontinuation of oral anticoagulant therapy (15.8 percent; average follow-up, 37.2 months), resulting in a relative risk of 0.99 (95 percent confidence interval, 0.57 to 1.73). During the initial nine months after randomization (after all patients received three months of therapy), 1 patient had a recurrence while receiving oral anticoagulant therapy (0.7 percent), as compared with 11 of the patients assigned to the discontinuation of oral anticoagulant therapy (8.3 percent; P=0.003). The incidence of recurrence after the discontinuation of treatment was 5.1 percent per patient-year in patients in whom oral anticoagulant therapy was discontinued after 3 months (95 percent confidence interval, 3.2 to 7.5 percent; average interval since discontinuation, 37.2 months) and 5.0 percent per patient-year in patients who received an additional 9 months of oral anticoagulant therapy (95 percent confidence interval, 3.1 to 7.8 percent; average interval since discontinuation, 29.4 months). None of the recurrences were fatal. Four patients had non-fatal major bleeding during the extended period of anticoagulant therapy (3.0 percent). CONCLUSIONS: In patients with idiopathic deep venous thrombosis, the clinical benefit associated with extending the duration of anticoagulant therapy to one year is not maintained after the therapy is discontinued.


Subject(s)
Anticoagulants/administration & dosage , Venous Thrombosis/drug therapy , Warfarin/administration & dosage , Acenocoumarol/administration & dosage , Acenocoumarol/therapeutic use , Administration, Oral , Adolescent , Adult , Aged , Aged, 80 and over , Anticoagulants/therapeutic use , Humans , International Normalized Ratio , Middle Aged , Recurrence , Time Factors , Treatment Outcome , Venous Thrombosis/prevention & control , Warfarin/therapeutic use
4.
J Immunother ; 24(2): 184-7, 2001.
Article in English | MEDLINE | ID: mdl-11265776

ABSTRACT

The aim of this study was to evaluate the direct action of IL-2 on recurrent superficial transitional bladder carcinoma and the effect on recurrence rate. 27 patients were submitted to neoadjuvant treatment by intra-vesical instillation of recombinant IL-2 and to transurethral resection. We did not observe any effect on neoplasms but the recurrence rate was less than the expected one. It is possible that treatment of bladder carcinoma with intra-vesical instillation of IL-2 may promote immuno-prophilaxis.


Subject(s)
Carcinoma, Transitional Cell/drug therapy , Interleukin-2/administration & dosage , Urinary Bladder Neoplasms/drug therapy , Aged , Carcinoma, Transitional Cell/pathology , Carcinoma, Transitional Cell/surgery , Chemotherapy, Adjuvant , Female , Humans , Interleukin-2/therapeutic use , Male , Middle Aged , Neoplasm Recurrence, Local , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use , Urethra , Urinary Bladder/drug effects , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/surgery
5.
Arch Ital Urol Androl ; 72(4): 254-6, 2000 Dec.
Article in Italian | MEDLINE | ID: mdl-11221049

ABSTRACT

An additional case of malakoplakia of the prostate in described to highlight its clinical, echographic and serum features. It's a rarest disease especially when prostate is involved, but well known in world literature. This case is reported to describe more accurately its echographic patterns and also for growing up precision in linguistical expressions used by echographists. We hope to contribute in collecting data about an uncommon pathology. At last we discuss about differential diagnosis when biopsy is negative for neoplasia and how it's possible to end further biopsies.


Subject(s)
Malacoplakia/blood , Malacoplakia/diagnostic imaging , Prostatic Diseases/blood , Prostatic Diseases/diagnostic imaging , Humans , Malacoplakia/diagnosis , Male , Middle Aged , Prostatic Diseases/diagnosis , Ultrasonography
6.
Surgery ; 126(1): 20-7, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10418588

ABSTRACT

BACKGROUND: The aim of this study was to determine whether clinical evaluation and duplex ultrasonography (DUS) alone can replace contrast cerebral arteriography (CA) for the detection of patients suitable for surgery at our institution. METHODS: During an 18-month period, 100 patients underwent DUS and CA during evaluation for carotid endarterectomy (CEA). All patients were studied prospectively; in each case an initial decision for or against CEA on the basis of DUS evaluation of the internal carotid arteries (ICAs) was subsequently compared with the surgeon's final management plan after CA. Of the 200 ICAs evaluated, 113 were considered for CEA but 14 were excluded from the study because the patient could not be evaluated before and after CA. This left 99 ICAs (86 patients) available for comparative analysis. RESULTS: The outcome of the 2 diagnostic modalities was perfectly consistent in 95.3% of the ICAs (kappa = 0.969). The clinical management decision was altered by the CA findings in only 2 cases (2%). Of the 99 ICAs considered suitable, 97 underwent CEA. No arteriographic complications occurred among the 100 patients undergoing CA. The perioperative stroke risk and mortality rates were 0%. CONCLUSIONS: Ninety-eight percent of the ICAs considered for surgery would have received appropriate clinical treatment on the strength of the patients' neurologic history and the outcome of DUS alone. Our results indicate that DUS is sufficient to establish the need for surgery in symptomatic and asymptomatic patients being considered for CEA and can replace CA in most clinical circumstances.


Subject(s)
Carotid Artery, Internal/diagnostic imaging , Endarterectomy, Carotid , Ultrasonography, Doppler, Duplex , Cerebrovascular Disorders/etiology , Cerebrovascular Disorders/mortality , Humans , Prospective Studies , Radiography , Sensitivity and Specificity
8.
BMJ ; 317(7165): 1037-40, 1998 Oct 17.
Article in English | MEDLINE | ID: mdl-9774286

ABSTRACT

OBJECTIVE: To investigate the efficacy of using a rapid plasma D-dimer test as an adjunct to compression ultrasound for diagnosing clinically suspected deep vein thrombosis. DESIGN: D-dimer concentrations were determined in all patients with a normal ultrasonogram at presentation. Repeat ultrasonography was performed 1 week later only in patients with abnormal D-dimer test results. MAIN OUTCOME AND MEASURES: Patients with normal ultrasonograms were not treated with anticoagulants and were followed for 3 months for thromboembolic complications. SETTING: University research and affiliated centres. SUBJECTS: 946 patients with clinically suspected deep vein thrombosis. RESULTS: Ultrasonograms were abnormal at presentation in 260 (27.5%) patients. Of the remaining 686 patients tested for D-dimer, 88 (12.8%) had abnormal concentrations. During follow up venous thromboembolic complications occurred in one of the 598 patients who were not treated with anticoagulants and who had an initial normal ultrasonogram and D-dimer concentration, whereas thromboembolic complications occurred in two of the 83 untreated patients who had abnormal D-dimer concentrations but a normal repeat ultrasonogram. The cumulative incidence of venous thromboembolic complications during follow up was 0.4% (95% confidence interval 0% to 0.9%). The rapid plasma D-dimer test used as an adjunct to compression ultrasonography resulted in a reduction in the mean number of repeat ultrasound examinations and additional hospital visits from 0.7 to 0.1 per patient. CONCLUSIONS: Testing for D-dimer as an adjunct to a normal baseline ultrasound examination decreased the number of subsequent ultrasound examinations considerably without any increased risk of venous thromboembolic complications in patients not receiving anticoagulants. The use of ultrasound and testing for D-dimer enabled treatment decisions to be made at the time of presentation in most patients.


Subject(s)
Fibrin Fibrinogen Degradation Products/analysis , Venous Thrombosis/diagnosis , Biomarkers , Cohort Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Predictive Value of Tests , Prospective Studies , Recurrence , Sensitivity and Specificity , Ultrasonography , Venous Thrombosis/diagnostic imaging
9.
Eur Urol ; 25(3): 220-5, 1994.
Article in English | MEDLINE | ID: mdl-7515349

ABSTRACT

We describe our experience with transurethral ultrasound-guided laser-induced prostatectomy (TULIP), a new procedure to relieve bladder outlet obstruction caused by benign prostatic hyperplasia. This device is composed of a real-time 7.5 MHz ultrasound transducer coupled to a Nd:YAG laser that fires through an intraprostatic balloon. To date, we performed 16 TULIP procedures; all patients were evaluated from a subjective point of view by a questionnaire based on the Boyarsky scale. They all underwent complete urodynamic studies, including flowmetry with measurement of the residual volume (by catheter) and pressure/flow studies. Preoperative symptom score ranged between 7 and 14 (mean 11.4). Preoperative peak flow rates ranged between 0 and 13 ml/s (mean 6.8). Suprapubic drainage was kept for a mean of 11.6 days after the procedure (7-20 days). Postoperative acute retention was observed in 4 patients (25%) 5-7 days after the procedure. In 13 out of 16 patients, urodynamic obstruction was corrected by the procedure. Two patients kept a borderline obstruction. In 1 case transurethral resection of the prostate (TURP) was performed for persisting obstruction and in another case TURP was performed for persisting untreatable irritative symptoms. At 3 months after the operation, the Boyarsky symptom score (11 patients) ranged between 3 and 12 (mean 7.7) and peak flow rates ranged between 11 and 30 ml/s (mean 16.3). One patient is managed with a suprapubic tube. Retrograde ejaculation was observed in 2 out of 9 patients (22.2%). With a mean follow-up of 6.7 months, we did not observe any late complication.


Subject(s)
Laser Therapy/methods , Prostatectomy/methods , Prostatic Hyperplasia/surgery , Follow-Up Studies , Humans , Male , Middle Aged , Prostatic Hyperplasia/epidemiology , Prostatic Hyperplasia/physiopathology , Time Factors , Ultrasonography, Interventional , Urodynamics/physiology
10.
J Cell Sci ; 101 ( Pt 1): 233-46, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1533224

ABSTRACT

A panel of monoclonal antibodies specific for cytoskeletal and cytocontractile protein markers has been used to study the expression of vimentin, desmin and alpha-smooth muscle (SM) actin, as well as non-muscle (NM) and SM myosin isoforms, in developing rabbit aorta. Immunofluorescence experiments show that in the vascular smooth muscle cells (SMC): (1) vimentin and alpha-actin of SM-type are homogeneously expressed among SMC, since the early stage (day 19, in uterus) of development; (2) desmin is heterogeneously distributed throughout all the developmental stages examined (from day 19, foetal, to day 90, post-natal); and (3) myosin isoform content in pre- and post-natal vascular SM is different when analyzed by anti-SM myosin (SM-E7) and anti-NM myosin (NM-F6, NM-A9 and NM-G2) antibodies. SM myosin in vascular SM is present as early as day 19 in uterus, being especially evident in the region facing the lumen of aortic wall, but not in the outermost layer in which NM myosin is present exclusively. Western blotting and immunofluorescence assays indicate that the foetal aortic SM is specifically labeled by all the three anti-NM myosin antibodies. However, immunoreactivity of aortic SM with NM-F6 and NM-A9 disappears completely around birth. Conversely, NM-G2 binding is maintained during post-natal development up to day 45; between day 45 and day 90 immunoreactivity of aortic SMC with this antibody diminished progressively, without disappearing, in a small number of cells. In aortic SMC cultures from foetal and adult rabbits, NM myosin immunoreactivities appear to be differently distributed, i.e. according to the stress fiber system (NM-F6 and NM-G2), in a diffuse manner (NM-A9) or mainly localized at the level of the cortical cytoplasm (NM-G2). The fact that a different pattern of NM myosin antigenicity can also be shown in other cell types, such as in the endothelium and the cardiac pericytes as well as in the renal parenchyma, is consistent with the existence of multiple NM myosin in vascular SM isoforms whose expression is developmentally regulated.


Subject(s)
Muscle, Smooth, Vascular/chemistry , Myosins/analysis , Animals , Antibodies, Monoclonal , Aorta , Blotting, Western , Cells, Cultured , Female , Gestational Age , Male , Rabbits
11.
J Cardiovasc Pharmacol ; 19 Suppl 2: S8-16, 1992.
Article in English | MEDLINE | ID: mdl-1377310

ABSTRACT

Vascular smooth muscle cells (SMCs) play a key role in the development of atherosclerotic lesions. Vascular smooth muscle, however, does not represent a homogeneous tissue. Using myosin as a marker of the differentiation processes in development and in vascular disease, we have been able to demonstrate the existence of distinct SMC populations in rabbit aorta. In our studies, a specific SMC population of the aortic media showing an "immature" type of myosin isoform expression accounted for the majority of SMCs present in the atherosclerotic plaque. Nifedipine, a dihydropyridine-derived calcium antagonist, was able to decrease the size of this particular SMC population and to prevent the development of atherosclerotic lesions in hypercholesterolemic rabbits. Here we report about a similar effect obtained by treating hypercholesterolemic rabbits with nitrendipine, another dihydropyridine-derived calcium antagonist. This article also summarizes the main experimental and clinical studies conducted on the antiatherogenic effect of calcium antagonists and focuses on the mechanisms underlying this effect, particularly at the vascular SMC level.


Subject(s)
Arteriosclerosis/prevention & control , Calcium Channel Blockers/therapeutic use , Muscle, Smooth, Vascular/drug effects , Animals , Arteriosclerosis/etiology , Arteriosclerosis/pathology , Cell Division/drug effects , Humans , Hypercholesterolemia/complications , Hypercholesterolemia/drug therapy , Muscle, Smooth, Vascular/pathology , Myosins/metabolism
13.
Arterioscler Thromb ; 11(5): 1376-89, 1991.
Article in English | MEDLINE | ID: mdl-1911723

ABSTRACT

The potential effect of thyroid hormones on the expression of cytoskeletal and cytocontractile proteins of vascular smooth muscle cells (SMCs) was examined by a panel of monoclonal antibodies and immunocytochemical procedures. L-Thyroxine was administered to adult New Zealand White rabbits for as long as 26 days, and the aortic SMC composition was studied at days 1, 2, 7, 15, and 26 from the beginning of hormonal treatment. A diffuse intimal thickening of the aorta became visible after 7 days of thyroxine administration. Histological and histochemical examination of intimal tissues from hyperthyroid rabbits revealed the presence of a homogeneous Sudan black-negative cell population. In immunofluorescence tests the intimal cells were found to be negative for antibodies specific for monocyte/macrophage or desmin and homogenously reactive (positive) for antibodies to vimentin and smooth muscle (SM) alpha-actin, thus indicating that cells present in the thickened intima were of the SM type. In addition, intimal SMCs from aortas of hyperthyroid rabbits showed a myosin isoform content similar to that found in normal developing aortic SM and in a specific medial SMC subpopulation of aortas from adult euthyroid animals. In the media underlying the intimal thickening, almost all the SMCs switched their myosin isoform expression toward the "immature" phenotype after 2 days of thyroxine treatment. When the level of thyroid hormones was reduced by propylthiouracil treatment, the medial SMC subpopulation with the immature myosin isoform content present in euthyroid rabbits completely disappeared. The study of DNA synthesis-related bromodeoxyuridine incorporation in aortas from hyperthyroid rabbits showed the presence of labeled nuclei in medial SMCs before the appearance of the intimal thickening as well as in the thickened intima and in the underlying media at days 7 and 15. These results are consistent with a specific role for thyroid hormones in inducing proliferation/migration of medial SMCs into the intima. Moreover, the switch in the expression of myosin isoforms induced by thyroid hormones appears to precede the accumulation of medial SMCs in the intima.


Subject(s)
Aorta/pathology , Hyperthyroidism/pathology , Myosins/analysis , Actins/analysis , Animals , Antibodies, Monoclonal , Aorta/metabolism , Bromodeoxyuridine/pharmacokinetics , Cholesterol/blood , Desmin/analysis , Endothelium, Vascular/pathology , Hyperthyroidism/chemically induced , Immunohistochemistry , Microscopy, Fluorescence , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Rabbits , Triglycerides/blood , Vimentin/analysis
14.
Arterioscler Thromb ; 11(4): 928-39, 1991.
Article in English | MEDLINE | ID: mdl-2065044

ABSTRACT

We evaluated the ability of the Ca2+ channel blocker nifedipine to influence the severity of atherosclerotic lesions and the pattern of aortic smooth muscle cell (SMC) differentiation in cholesterol-fed New Zealand White rabbits. The animals were fed a 1% cholesterol-enriched diet for 12 weeks. After 4 weeks of the diet, some rabbits were given nifedipine (20 mg b.i.d.) for another 8 weeks without discontinuation of the cholesterol-enriched diet (experiment 1). Another group of rabbits was treated with nifedipine from the beginning of the cholesterol-enriched diet for the entire 12 weeks (experiment 2). The severity of ahterosclerotic lesions was determined by computerized planimetry, and qualitative effects of nifedipine on SMCs were studied by monoclonal antibodies specific for smooth muscle and nonmuscle myosins. In the aortic media of normal rabbits, these antibodies can identify an SMC population with an "immature" type of myosin pattern; a marked increase in the number of these cells is observed during atherogenesis. In experiment 1, we observed a marked decrease of medial SMCs with the immature type of myosin pattern, without any significant reduction in atherosclerosis severity. In experiment 2, disappearance of the previously mentioned medial SMC population was accompanied by a dramatic slowing of intimal lesion development. These results indicate that nifedipine treatment is effective in reducing atherosclerotic lesions only when given from the beginning of a cholesterol-enriched diet. Delay of nifedipine administration until the fourth week of the cholesterol-enriched diet fails to halt progression of the disease. The observed antiatherosclerotic activity can be attributable to a direct effect of the drug on the medial SMC population, which increases during the course of experimental atherogenesis.


Subject(s)
Arteriosclerosis/metabolism , Muscle, Smooth, Vascular/drug effects , Nifedipine/pharmacology , Animals , Aorta, Thoracic/pathology , Arteriosclerosis/pathology , Arteriosclerosis/prevention & control , Cell Division/drug effects , Cells, Cultured , Cholesterol, Dietary/administration & dosage , Fluorescent Antibody Technique , Image Processing, Computer-Assisted , Male , Muscle, Smooth, Vascular/pathology , Myosins/metabolism , Rabbits
15.
Hypertension ; 17(4 Suppl): III75-81, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2013498

ABSTRACT

Current knowledge of the links between the sympathetic nervous system and vascular damage in hypertension and atherosclerosis is summarized. The main mechanisms leading to the structural changes of the arterial wall as a consequence of enhanced adrenergic drive are reported. Hemodynamic mechanisms, including increase in pressure leading to changes in the arterioles and alteration of flow pattern with impact mainly in the large arteries, respectively, account for the typical target organ damage observed in hypertension and is involved in the development of atherosclerotic lesions. Regarding the direct effect of catecholamines, the atherogenic effects of epinephrine and norepinephrine in the absence of changes in blood pressure and cholesterol levels have been demonstrated in vivo in monkeys and rabbits. In rats, catecholamine administration induces polyploidization of aortic smooth muscle cells in vivo and in vitro. Regarding the effects of lipid metabolism, adrenergic stimulation may induce free fatty acid transformation into triglycerides with secondary increase in very low density lipoprotein plasma levels and decrease of very low density lipoprotein transformation into high density lipoprotein through circulating lipoprotein lipase inhibition. Catecholamines may also increase cholesterol levels of the arterial wall, probably by triggering the acyl-cholesterol-acyl-transferase activity. Finally, indirect evidence of the pathogenetic role played by the sympathetic system in the development of vascular disease derives from the results of experiments showing that sympatholytic agents are capable of reducing both medial hypertrophy and atherogenesis. beta-Blockers, alpha- and beta-blockers, and centrally acting sympatholytic agents not only ameliorate hemodynamics but also appear to inhibit the direct effects of catecholamines on the arterial wall.


Subject(s)
Arteries/pathology , Arteriosclerosis/physiopathology , Hypertension/physiopathology , Sympathetic Nervous System/physiopathology , Antihypertensive Agents/pharmacology , Arteriosclerosis/pathology , Hemodynamics , Humans , Hypertension/pathology , Norepinephrine/physiology , Stress, Physiological/physiopathology
16.
Basic Res Cardiol ; 86(1): 70-8, 1991.
Article in English | MEDLINE | ID: mdl-1826995

ABSTRACT

We studied subunit composition and Ca(++)-activated ATPase activity of myosin isolated from atria and ventricles of hearts explanted from patients suffering from idiopathic dilated cardiomyopathy. At variance with previously published data, we have been unable to detect in the ventricular subendocardial layers a significant amount of myosin atrial-like light chain 1 (ALC1), which has been reported to be related to some hemodynamic features of the hypertrophied and failing heart. Such a subunit was not visible in the septum and in the subepicardial layers either. On the contrary, in both atria a ventricular-like light chain 2 (VLC2) was found. The nature of this additional light chain was confirmed on the basis of two-dimensional electrophoresis and immunoblotting techniques with polyclonal antibodies reacting with VLC2. In these patients we also observed a depressed Ca(++)-activated ATPase activity, both in atrial and ventricular myosin. The explanation for this finding in ventricles still remains obscure since neither myosin light chains, nor myosin heavy chains showed any difference between patients with dilated cardiomyopathy and controls. On the contrary, in atria we clearly identified changes consistent with the expression of myosin heavy chains of ventricular type and VLC2, which can account for the depressed Ca(++)-activated ATPase activity.


Subject(s)
Cardiomyopathy, Dilated/metabolism , Heart Atria/chemistry , Heart Septum/chemistry , Heart Ventricles/chemistry , Myosins/metabolism , Calcium-Transporting ATPases/analysis , Electrophoresis, Gel, Two-Dimensional , Humans , Immunoblotting , Male , Myosins/chemistry , Organ Culture Techniques , Protein Conformation
17.
Arteriosclerosis ; 10(6): 996-1009, 1990.
Article in English | MEDLINE | ID: mdl-1700896

ABSTRACT

Two monoclonal antimyosin antibodies, Western blotting experiments, and immunofluorescence procedures were used to investigate myosin isoform expression in normal and atherosclerotic aortas of adult rabbits. The SM-E7 antibody reacted with the two myosin heavy chain (MHC) isoforms of smooth muscle (SM) type (SM-MHC-1 and SM-MHC-2) expressed in the adult rabbit aorta. The NM-G2 antibody recognized an epitope shared by the nonmuscle (NM) myosin heavy chains (NM-MHC) present in fibroblasts, macrophages, lymphocytes, and platelets. Two smooth muscle cell (SMC) populations were identified in the medial layer of normal adult aorta, namely cells that contained SM myosin exclusively and cells that showed the coexistence of SM and NM myosin isoforms. The size of the cell population with double myosin isoform content increased markedly during experimental atherogenesis and represented by far the predominant SMC phenotype in the atherosclerotic plaque. Western blotting analysis performed on crude extracts from the atherosclerotic plaque showed the presence of SM-MHC-1 and NM-MHC isoforms in this tissue. Co-expression of SM and NM myosin at the molecular and the cellular level were found in aortic tissue during the early stages of development. These results indicate that in experimental atherosclerosis, the accumulation in the plaque of SMC with an "immature" pattern of myosin isoform expression is accompanied by similar modifications in the differentiation pattern of SMC of the underlying media.


Subject(s)
Arteriosclerosis/metabolism , Muscle, Smooth, Vascular/chemistry , Myosins/chemistry , Animals , Animals, Newborn , Antibodies, Monoclonal , Antibody Specificity , Aorta , Arteriosclerosis/pathology , Blotting, Western , Cells, Cultured , Diet, Atherogenic , Epitopes , Fluorescent Antibody Technique , Immunohistochemistry , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/pathology , Myosins/analysis , Myosins/immunology , Rabbits
18.
Dev Biol ; 141(2): 431-46, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2145187

ABSTRACT

Monoclonal anti-smooth muscle (SM-E7, SM-F11, and BF-48) and anti-nonmuscle (NM-A9 and NM-G2) myosin antibodies, Western blotting, and immunocytochemical procedures were used to study myosin isoform composition and distribution in the smooth muscle (SM) cells of bovine aorta differentiating in vivo and in vitro. Two myosin heavy chain (MHC) isoforms were identified by SM-E7 in adult aorta: SM-MHC-1 (Mr = 205 kDa) and SM-MHC-2 (Mr = 200 kDa), respectively. When tested with the SM-F11 antibody, SM-MHC-2 isoform showed distinct antigenic properties compared to SM-MHC-1. Two bands of 205 and 200 kDa were also present in the aortic SM tissue from 3-month-old fetus and were equally recognized by the BF-48 antibody. The 200-kDa SM myosin isoform was labeled by SM-F11 but not by SM-E7, thus indicating the existence of a fetal-specific SM-MHC-2 isoform. At the cellular level, both developing and adult bovine aortic tissues showed the existence of distinct patterns of myosin isoform expression. Three or even more aortic cell populations are differently distributed in areas which appear as (1) a network of interconnecting sheet-like or compact tissue (early fetus) and (2) enriched of collagenous-elastic or muscular tissue (adult animal). In addition, the SM-MHC-2 isoform of the fetal type appears to be uniquely distributed in cultured SM cells grown in vitro from adult bovine aortic explants. Our data indicate that in bovine aorta (1) MHC isoform expression is developmentally regulated and (2) the distribution of myosin isoforms is heterogenous both among and within aortic cells. These findings may be related to the distinct physiological properties displayed by SM during vascular myogenesis.


Subject(s)
Muscle, Smooth, Vascular/cytology , Myosins/analysis , Animals , Antibodies, Monoclonal , Antibody Specificity , Aorta/cytology , Aorta/enzymology , Blotting, Western , Cattle , Cells, Cultured , Chromatography, Affinity , Electrophoresis, Polyacrylamide Gel , Fluorescent Antibody Technique , Immunohistochemistry , Muscle, Smooth, Vascular/enzymology
19.
Exp Cell Res ; 190(1): 1-10, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2201550

ABSTRACT

A panel of monoclonal antibodies, specific for human platelet (NM-A9, NM-F6, and NM-G2) and for bovine smooth muscle (SM-E7) myosin heavy chains (MHC), were used to study the composition and the distribution of myosin isoforms in bovine endothelial cells (EC), in vivo and in vitro. Using indirect and double immunofluorescence techniques, we have found that in the intact aortic endothelium there is expression of nonmuscle MHC (NM-MHC), exclusively. By contrast, hepatic sinusoidal endothelium as well as cultured bovine aortic EC (BAEC) in the subconfluent phase of growth show coexistence of NM- and smooth muscle MHC (SM-MHC) isoforms. SM myosin immunoreactivity disappears when cultured BAEC become confluent. In this phase of cell growth, NM-MHC isoforms are localized differently within the cells, i.e., in the cytoplasm around the nucleus or in the cortical, submembranous region of EC cytoplasm. A third type of intracellular distribution of NM-MHC immunoreactivity was evident in the cell periphery of binucleated, confluent BAEC. These data indicate that (1) several myosin isoforms are differently distributed in bovine endothelia; and (2) SM myosin expression and the specific subcellular localization of NM myosin isoforms within EC might be regulated by cell-cell interactions.


Subject(s)
Endothelium, Vascular/analysis , Myosins/analysis , Animals , Antibodies, Monoclonal , Aorta/cytology , Blotting, Western , Cattle , Endothelium, Vascular/cytology , Fluorescent Antibody Technique , Liver/blood supply , Muscle, Smooth
20.
Drugs Exp Clin Res ; 16(3): 123-8, 1990.
Article in English | MEDLINE | ID: mdl-1974839

ABSTRACT

This paper deals with some changes at the cardiac and aortic levels observed in normotensive rats and in hypertensive rats and turkeys by using two different beta-blockers, namely propranolol and oxprenolol. Chronic treatment with propranolol induced in the heart of normotensive rats a shift in the ventricular myosin pattern toward the "slow" V2 and V3 isoforms which are characterized by a reduced oxygen consumption. Oxprenolol treatment did not modify the blood pressure levels in the renal hypertensive rats nor in the spontaneously hypertensive turkeys. Nevertheless, in both experimental models a substantial modification of the media and intima, respectively, took place. In untreated hypertensive and normal rats the thickness of the aortic media was significantly higher than that of the treated ones, therefore suggesting a direct effect of oxprenolol on the smooth muscle cells of the aortic media. In the spontaneously hypertensive turkeys the atherosclerotic plaques appeared to be more frequent and thicker than those found in the oxprenolol-treated animals. These two experiments demonstrate that beta-blockers can prevent the development of hypertrophy of the media and decrease both the incidence and severity of intimal proliferations independently of blood pressure control. It therefore appears that the well-known myocardial protective effect played by beta-blockers, which mainly consists of a reduced myocardial oxygen consumption, is certainly obtained by reducing blood pressure and heart rate but also by changing the contractile protein pattern. In addition, an indirect myocardial protective effect could be exerted by beta-blockers at the vascular level by preventing medial hypertrophy and the development of atherosclerosis.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Hypertension/drug therapy , Animals , Aorta/drug effects , Aorta/physiopathology , Blood Pressure/drug effects , Calcium-Transporting ATPases/metabolism , Cardiomegaly/prevention & control , Coronary Artery Disease/drug therapy , Coronary Artery Disease/physiopathology , Heart/drug effects , Heart/physiopathology , Heart Rate/drug effects , Hypertension/physiopathology , Male , Myocardium/enzymology , Organ Size/drug effects , Oxprenolol/therapeutic use , Propranolol/therapeutic use , Rats , Rats, Inbred Strains , Turkeys
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