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Biomedical subjects

L Badimon

Publications and source records attributed to L Badimon.

At least 37 records · Page 2Linked to original sources
PubMed2001

3-hydroxy-3-methylglutaryl coenzyme a reductase inhibition prevents endothelial NO synthase downregulation by atherogenic levels of native LDLs: balance between transcriptional and posttranscriptional regulation.

Atherogenic levels of native low density lipoproteins (nLDLs) decrease the bioavailability of endothelium-derived NO and downregulate endothelial NO synthase (eNOS) expression in cultured human endothelial cells. Here, we show that simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, within the therapeutic range (0.01 to 1 micromol/L) prevented the downregulation of eNOS mRNA and protein promoted by nLDL (180 mg cholesterol/dL, 48 hours) in human umbilical vein endothelial cells. This effect of simvastatin was completely reversed by mevalonate, the product of the reaction, and to a lesser extent by farnesol and geranyl geraniol. Simvastatin significantly stabilized eNOS mRNA in cells treated with nLDL during 48 hours (eNOS mRNA half-life approximately 11 hours in controls versus >24 hours in nLDL per 0.1 micromol/L simvastatin-treated cells). The downregulation of eNOS by nLDL was abrogated by cycloheximide, an inhibitor of protein synthesis, and by N-acetyl-leucyl-leucyl-norleucinal, a protease inhibitor that reduces the catabolism of sterol regulatory element binding proteins. Sterol deprivation increased the downregulation produced by nLDL on eNOS and sterol regulatory element binding protein-2 expression levels. However, no differential modulation of the retardation bands corresponding to the putative sterol-responsive element present in the eNOS promoter was detected by electrophoretic mobility shift assay. Our results suggest that nLDL promote eNOS downregulation operating at a transcriptional level, whereas simvastatin prevents such an effect through a posttranscriptional mechanism.

Arteriosclerosis↗
PubMed2001

Atherosclerosis and thrombosis: lessons from animal models.

Atherothrombosis defines the occurrence of thrombosis on atherosclerotic lesions. Atherosclerosis is the most prevalent disease of our time and its thrombotic complications are responsible for an exceedingly high number of deaths and disabilities. Over the past few years, experimental investigation and clinical and pathologic observations have led to a better understanding of how a thrombus forms and also of its incidence in acute ischemic syndromes. A thrombus is usually found secondary to atherosclerotic plaque disruption. Mural thrombosis, also at the site of plaque rupture, is an important mechanism in the progression of atherosclerosis even when symptoms are absent. Because atherosclerosis is a silent and asymptomatic disease until complications arise with thrombosis producing clinical symptoms, it is necessary to have models that reproduce the human disease in its early stages. Unfortunately, not all the experimental models of vascular disease have human resemblance and validity. Knowledge of the disease process and of what an experimental animal model can offer is a milestone for a successful investigation. Experimental models of vascular disease have enhanced our understanding of the pathophysiological processes leading to vascular obstruction in both spontaneous and accelerated atherosclerosis and thrombosis. Animal models have provided insight into the role of platelets, lipids, renin-angiotensin system (RAS), cytokines and growth factors in the evolution and progression of atherosclerosis and have suggested potential therapeutic interventions. Significant advances in our understanding of the vascular biology and pathology of atherosclerosis and thrombosis, and of the interactions of blood cells, lipids and proteins with the vascular wall, have allowed us to formulate new experimental hypotheses and to test therapeutic strategies, either pharmacological or surgical.

Animals↗
PubMed2000

Antithrombotic effects of abciximab.

The observation that platelet-platelet interaction and thrombosis are ultimately regulated by the glycoprotein (GP) IIb/IIIa receptor complex, triggered the development of agents capable of interfering with this platelet receptor complex. Several large clinical trials have demonstrated the effectiveness of this class of agents. The first of these agents to show beneficial effects after coronary interventions was the mouse/human chimeric Fab fragment antibody c7E3 (abciximab; ReoPro). This study analyzes whether the addition of heparin to the GP IIb/IIIa antagonist abciximab would enhance the antithrombotic effect. Blood drawn directly from patients on aspirin who underwent interventional procedures perfused an ex vivo perfusion chamber containing a severely injured arterial wall at local rheologic conditions of a mildly stenosed coronary artery. Blood was perfused directly from patients at baseline and following administration of heparin, abciximab, or both. The antithrombotic effects of the 3 treatments were assessed by reduction of the thrombus formation on the perfused specimens. Thrombus formation at baseline was not significantly modified by the administration of heparin (13,897 +/- 1,316 vs 11,917 +/- 1,519 microm(2)). Abciximab produced a 58% reduction in thrombus formation (11,631 +/- 861 vs 4, 925 +/- 585 microm(2); p <0.001). The addition of heparin to abciximab did not further reduce thrombus area versus abciximab alone (5,651 +/- 581 vs 4,925 +/- 585 microm(2)). Thus, our data show that abciximab dramatically decreases mural thrombus formation and that combining heparin with abciximab did not add any additional antithrombotic effect to abciximab alone.

Abciximab↗
PubMed2000

Small oxidative changes in atherogenic LDL concentrations irreversibly regulate adhesiveness of human endothelial cells: effect of the lazaroid U74500A.

The adherence of monocytes to the endothelium is an early event in atherogenesis which is modulated by low density lipoproteins (LDL). We analyzed the effect of atherogenic LDL levels (180 mg cholesterol/dl, for 24 h) with minimal oxidative modifications (thiobarbituric-acid-reactive-substances (TBARS) concentration between 1.2+/-0.1 and 2.5+/-0.3 nmol of malonaldehyde bis-diethyl acetal (MDA) per mg protein) on human umbilical vein endothelial cell (HUVEC) adhesive properties. We used native LDL (n-LDL), and LDL exposed to spontaneous oxidation without antioxidants (mox-LDL) or with 20 micromol/l of the antioxidant butylated hydroxytoluene (BHT-LDL) or 10 micromol/l U74500A (U74500A-LDL), a scavenger of free radicals. Thiobarbituric-acid-reactive-substances (TBARS) levels were significantly higher in mox-LDL (2.5+/-0.3 nmol MDA/mg protein) than in BHT-LDL (1.6+/-0.2), U74500A-LDL (1.2+/-0.1) or in n-LDL (1.3+/-0.1). mox-LDL induced the greatest adhesion of U937 cells to HUVEC (103+/-9% over controls) followed by BHT-LDL (75+/-10%), U74500A-LDL (36+/-9%) and n-LDL (35+/-3%). The lazaroid U74500A efficiently protected U74500A-LDL against oxidative damage and prevented endothelial adhesiveness associated with this LDL modification, inducing adhesion effects similar to those of n-LDL. However, U74500A could not reverse the adhesion induced by previously oxidized LDL (mox-LDL). LDL did not induce the expression of the intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) or E-selectin, but it produced a downregulation of endothelial nitric oxide synthase (NOS III) mRNA levels. Thus, adhesiveness of human endothelial cells (EC) exposed to atherogenic concentrations of LDL is closely modulated by minimal changes in LDL oxidative state, and could be related to a downregulation of NOS III.

Analysis of Variance↗
PubMed2000

Effect of gemfibrozil on peripheral atherosclerosis and platelet activation in a pig model of hyperlipidemia.

BACKGROUND: Gemfibrozil has been shown to have beneficial effects in the primary and secondary prevention of atherosclerosis. However, a platelet pro-activating effect induced by the drug has been reported. MATERIAL AND METHODS: We analysed the effect of hyperlipidemia and its treatment with gemfibrozil on platelet-fibrinogen binding and the development of early fibrinogen-rich vascular lesions in a porcine model of atherosclerosis. Polyclonal antibodies were raised against purified pig fibrinogen and intact platelets. Two groups of animals were fed a cholesterol/saturated fat-enriched diet for 50 days; one group was treated with gemfibrozil and the other with placebo. RESULTS: The hyperlipidemic diet induced a significant increase in total cholesterol; this was prevented by gemfibrozil (P<0.05). The increase in platelet-fibrinogen binding induced by hypercholesterolemia was mildly reduced in the gemfibrozil treated animals. Histological analysis of aortic vascular wall (abdominal aorta at the iliac bifurcation) from hyperlipidemic animals showed early lesions with fibrinogen infiltration; the lesions were reduced in the fibrate-treated animals. CONCLUSIONS: Gemfibrozil delayed the development of peripheral atherosclerotic plaque, normalised the impaired lipid profile induced by the hyperlipidemic diet and did not show a functionally detectable platelet pro-activating effect able to increase platelet-fibrinogen binding.

Animals↗
PubMed2000

D-Dimer is an early diagnostic marker of coronary ischemia in patients with chest pain.

BACKGROUND: Chest pain is a frequent symptom in the emergency department and often presents a diagnostic challenge. Because coronary thrombosis is a hallmark of acute ischemic syndromes, the substrates of the coagulation and fibrinolysis cascades may be markers of coronary ischemia. The objective of this study was to determine the diagnostic value of several hemostatic markers in patients presenting to the emergency department (ED) with chest pain syndromes. METHODS: Two hundred fifty-seven consecutive patients with acute chest pain were studied in this prospective study conducted in an urban ED. D-Dimer levels were measured at admission to the ED in all patients. We also measured thrombin-antithrombin complexes, prothrombin fragment 1+2, activated factor VII, and fibrinogen. We used regression analysis to estimate the likelihood of myocardial infarction and the diagnostic value of D-dimer. RESULTS: D-Dimer and fibrinogen levels were significantly higher in patients with acute ischemic events (myocardial infarction and unstable angina) than in nonischemic patients (P <.01 and P =.02, respectively). The other hemostatic markers were not significantly elevated in patients with ischemic events. D-Dimer level >500 microg/L had an independent diagnostic value for myocardial infarction and increased the diagnostic sensitivity of the electrocardiogram and history from 73% to 92%. CONCLUSION: D-Dimer, an expression of ongoing thrombus formation and lysis, is a marker of substantial incremental value for the early diagnosis of acute coronary syndromes presenting with chest pain. It adds independent information to the traditional assessment for myocardial infarction. D-Dimer can be incorporated into clinical decision models in the ED.

Adult↗
PubMed2000

LDL receptor-related protein mediates uptake of aggregated LDL in human vascular smooth muscle cells.

Foam cell formation is a key event in the onset and progression of atherosclerotic lesions. We have previously reported that internalization of aggregated low density lipoproteins (agLDLs) by vascular smooth muscle cells (VSMCs) produces cholesteryl ester (CE) accumulation in these cells. The aim of this study was to analyze whether the low density lipoprotein receptor-related protein (LRP) mediates the uptake of agLDL by VSMCs. First, immunocytochemistry and fluorescence microscopic analysis with the use of anti-LRP antibodies indicated that there was a high expression of LRP in VSMCs. Confocal microscopic analysis with the use of agLDLs labeled with fluorochrome 1,1'-dioctadecyl-3,3,3', 3'-tetramethylindocarbocyanine and anti-LRP antibodies showed the colocalization of agLDL and LRP. The second approach was to analyze the effect of LRP ligands on agLDL internalization; lactoferrin strongly inhibited CE accumulation from agLDLs (85.0+/-5.7% at 25 microg/mL) by impairing agLDL binding. Coincubation of agLDL with anti-LRP antibodies decreased in a dose-dependent manner agLDL-derived CE accumulation (from 20% at 12.5 microg/mL to 80% at 50 microg/mL). The third approach was to evaluate whether antisense LRP oligodeoxynucleotides were able to block agLDL internalization. Treatment of VSMCs with 5 micromol/L antisense LRP oligodeoxynucleotides reduced agLDL-derived CE accumulation by 84+/-2%. In conclusion, these results from immunologic, biochemical, and molecular interventions demonstrate that LRP mediates the binding and internalization of agLDL in human VSMCs. Because LRP is highly expressed in VSMCs and the uptake of 1 LDL aggregate amounts to the deposition of several hundreds of LDL particles, the uptake of agLDL through LRP could have a crucial role for lipid deposition in VSMCs.

Antibodies↗
PubMed1999

Local inhibition of tissue factor reduces the thrombogenicity of disrupted human atherosclerotic plaques: effects of tissue factor pathway inhibitor on plaque thrombogenicity under flow conditions.

BACKGROUND: Plaque disruption and subsequent thrombus formation lead to acute coronary syndromes and progression of atherosclerotic disease. Tissue factor (TF) appears to mediate plaque thrombogenicity. Tissue factor pathway inhibitor (TFPI) is the major physiological inhibitor of TF. This study analyzes the role of TF on thrombogenicity of disrupted human atherosclerotic plaques and the therapeutic possibilities of its specific inhibition. METHODS AND RESULTS: Human atherosclerotic and normal arterial segments were exposed to heparinized blood at flow conditions modeling medium-grade coronary stenosis in the Badimon perfusion chamber. The antithrombotic effects of the specific inhibition of plaque TF was assessed by reduction in the deposition of radiolabeled platelets and fibrin(ogen) and immunohistochemical analysis of perfused arteries. TF activity was inhibited by both recombinant TFPI and a polyclonal antibody against human TF. Human lipid-rich plaques were more thrombogenic than less advanced atherosclerotic plaques. Specific inhibition of TF activity reduced plaque thrombogenicity, inhibiting both platelet and fibrin(ogen) deposition (580 versus 194 plateletsx10(6)/cm2; P<0.01, and 652 versus 172x10(12) molecules of Fg/cm2; P<0.05, respectively) and thrombosis (immunohistochemistry). CONCLUSIONS: This study documents the key role of TF activity in acute arterial thrombosis after atherosclerotic plaque disruption and provides evidence of the benefit of blocking plaque TF activity. Therefore the inhibition of the TF pathway opens a new therapeutic strategy in the prevention of acute coronary thrombosis after plaque disruption.

Animals↗
PubMed1999

Differential cholesteryl ester accumulation in two human vascular smooth muscle cell subpopulations exposed to aggregated LDL: effect of PDGF-stimulation and HMG-CoA reductase inhibition.

Vascular smooth muscle cells (VSMC) are a major component of atheromatous plaque and they exhibit a high heterogeneity in morphology and proliferative activity. Two cell subpopulations from the media of human pulmonary artery were isolated according to the kinetics of outgrowth from the explants; the first wave of cell outgrowth (VSMC-I) and the second wave (VSMC-II) were separately cultured. They were characterized by premitotic DNA synthesis ([3H]thymidine incorporation) and cholesterol synthesis ([14C]acetate incorporation). DNA and cholesterol synthesis were approximately 13- and 5-fold, respectively, higher in VSMC-I than in VSMC-II. When these subpopulations were exposed to 100 micrograms/ml of aggregated low density lipoproteins (agLDL), their cholesteryl ester (CE) content increased 4.3-fold over that induced by native LDL. The increase in CE induced by native or agLDL was approximately 2.7-fold higher in VSMC-I than in VSMC-II. These results suggest that agLDL uptake is related, at least in part, to the cellular proliferative status. Platelet derived growth factor (PDGF) did not increase agLDL uptake in any subpopulation, although it efficiently promoted proliferative activity in both cell types and increased native LDL uptake and cholesterol synthesis in VSMC-II. Simvastatin strongly inhibited CE accumulation from agLDL in VSMC-I, either unstimulated or PDGF-stimulated (> 80% inhibition). In contrast, it only blocked agLDL uptake in PDGF stimulated VSMC-II (50% inhibition). Our results indicate that the quantitative effect of simvastatin on CE accumulation from agLDL is dependent on phenotypic cell characteristics and it can be modulated in response to mitogenic stimulus.

Arteriosclerosis↗
PubMed1999

Nitric oxide synthase II (NOS II) gene expression correlates with atherosclerotic intimal thickening. Preventive effects of HMG-CoA reductase inhibitors.

HMG-CoA reductase inhibitors have been shown to be effective in primary and secondary prevention of coronary heart disease. Their mechanism of action is attributed to their cholesterol lowering activity but recent results seem to indicate additional effects related to the modulation of other processes that regulate the presentation of vascular diseases. Our objective has been to study the effects of atorvastatin and simvastatin, two HMG-CoA reductase inhibitors, on lesion composition and expression of genes involved in lesion development in a diet-induced atherosclerotic rabbit model. Both HMG-CoA reductase inhibitors were administered at identical doses of 2.5 mg/kg per day with the hyperlipemic diet for 10 weeks. Both statins significantly prevented the diet-induced increase in cholesterol levels. Relative lesion composition in fibrinogen, macrophages and smooth muscle cells was unaltered by the treatment although lesion size was reduced; therefore, both HMG-CoA reductase inhibitors reduced total amounts of fibrinogen, macrophages and smooth muscle cells (simvastatin, P < 0.05). NOS II gene expression was positively and significantly correlated with lesion size and inversely correlated with HDL plasma levels. NOS II expression was markedly downregulated in simvastatin treated animals while MCP-1 was unaltered. Therefore, HMG-CoA reductase inhibition seems to interfere with atherosclerotic lesion development by reducing intimal thickening development and the expression of the cytotoxic NOS II.

Animals↗
PubMed1999

Effects of dietary fatty acids and vitamin E levels in HL-60 cell proliferation.

BACKGROUND: Fatty acids have shown to be both modulators and messengers of signals triggered at the level of cell membranes. There is, however, controversy about the role of fatty acids in cell proliferation kinetics, and it is still unknown whether cell proliferation can be regulated by fatty acid dietary intake in humans. Our objective was to investigate whether feasible changes in the human dietary food intake that induce significant changes in lipids, fatty acids and the oxidative state were able to influence proliferation kinetics of the leukaemia cell line HL-60. MATERIALS AND METHODS: Healthy men and women were subjected to four consecutive dietary periods with increasing degree of unsaturation: saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), n-6 polyunsaturated fatty acids (n-6 PUFAs), n-3 polyunsaturated fatty acids (n-3 PUFAs). Plasma lipids and oxidation parameters were controlled during each period. Serum from each subject in the four dietary periods was incubated for 3 days with the leukaemia cell line, HL-60 (250 x 10(3) cell mL-1), to study cell proliferation. RESULTS: In men, an n-3 polyunsaturated fatty acid-enriched diet showed a significant inhibition of DNA duplication with respect to a saturated-enriched diet, but the effect is not sufficient in blocking cell proliferation. However, as expected, the in vitro addition of fatty acids to HL-60 cells significantly halted proliferation. In addition, the HL-60 growth ratio was shown to be inversely correlated with plasma vitamin E (P = 0.0004) and oleic acid in phospholipids (P = 0.01) in plasma of the individuals in the dietary intervention study. CONCLUSIONS: Our results demonstrate that changes in serum fatty acid composition obtained with dietary changes, without extreme variations of the regular diets of a free-living population, cannot block HL-60 cell proliferation.

Adolescent↗
PubMed1999

Regulatory effects of HDL on smooth muscle cell prostacyclin release.

One mechanism by which high density lipoproteins (HDLs) exert their protective effect against coronary artery disease could be related to the induction of prostacyclin (PGI(2)) release in the vessel wall. We have recently shown that HDL increases PGI(2) production in rabbit smooth muscle cells (RSMCs) and that this increase is dependent on cyclooxygenase-2 (Cox-2). Here we analyze the mechanism by which rabbit HDL induces PGI(2) release in RSMCs. Our results show that although HDL(2) and HDL(3) share a similar capacity to induce Cox-2 protein levels, HDL(3) stimulates a higher PGI(2) release than does HDL(2), probably because of their relative arachidonate contents. Acetylsalicylic acid pretreatment (300 micromol/L, 30 minutes) significantly reduced the HDL-induced PGI(2) release, suggesting that both preexisting and induced Cox-2 activities were involved in the HDL effect. Ca(2+)-dependent cytosolic phospholipase A(2) (cPLA(2)) and Cox-1 protein levels were not altered by HDL. Dexamethasone (2 micromol/L), which also inhibited the HDL-induced PGI(2) release, reduced significantly both Cox-2 mRNA and protein levels without affecting cPLA(2) and Cox-1 protein levels. In addition, methylarachidonyl fluorophosphonate, a potent inhibitor of cPLA(2), did not produce any effect on HDL-induced PGI(2) release. In the presence of cycloheximide, Cox-2 mRNA levels were induced by HDL and inhibited by dexamethasone, suggesting that HDL and dexamethasone work in the absence of de novo protein synthesis. These results indicate an early effect of HDL on PGI(2) biosynthesis, specifically increasing Cox-2. PD98059, an inhibitor of mitogen-activated protein kinase kinase, completely inhibited HDL-induced PGI(2) release, whereas GF109203X, a protein kinase C inhibitor, had no effect. Thus, HDL induces PGI(2) synthesis by a mechanism dependent on the mitogen-activated protein kinase pathway but independent of protein kinase C.

Animals↗
PubMed1999

Platelet deposition on eroded vessel walls at a stenotic shear rate is inhibited by lipid-lowering treatment with atorvastatin.

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase are widely used in the treatment of dyslipemias and have shown beneficial effects in the primary and secondary prevention of cardiovascular diseases. However, regression studies with lipid-lowering drugs have not shown significant lesion reduction associated with the improvement in clinical events. Therefore, our objective has been to study whether treatment with a lipid-lowering drug of this family, atorvastatin, could reduce platelet deposition on the damaged vessel wall at different shear stress conditions, simultaneously with retardation of the development of atherosclerotic lesions. Using cholesterol-fed swine as the model, we found that atorvastatin significantly diminished platelet deposition on the mildly damaged vessel wall at high shear rates (50%, P<0.01), but it did not have any effect in preventing platelet deposition triggered by a severely injured vessel wall. Development of coronary lesions was also reduced by treatment. These findings suggest that atorvastatin may prevent platelet attachment to eroded vessels and hence, contribute to reducing the thrombotic risk associated with the erosions of the luminal surface and the platelet-dependent progression of atherosclerotic plaques.

Animals↗
PubMed1999

Effects of statins in thrombosis and aortic lesion development in a dyslipemic rabbit model.

HMG-CoA reductase inhibitors (statins) are effective in primary and secondary prevention of coronary heart disease. The mechanism of action is mainly attributed to their plasma cholesterol lowering activity, although additional effects have been suggested. Our objective was to study whether atorvastatin and simvastatin exhibited an inhibitory effect on platelet deposition onto a triggering damaged vessel wall in addition to an antiatherosclerotic effect in the dyslipemic rabbit model. Statins were administered at identical doses of 2.5 mg/kg/day with a hyperlipidemic diet during 10 weeks. Both drugs similarly lowered total cholesterol and, moderately, triglycerides. Mural platelet deposition on damaged vessel wall placed in an ex-vivo flow perfusion system was reduced in atorvastatin treated animals (39.7+/-6.2 X 10(6) PLT/cm2) vs. controls (94.8+/-15.9 x 10(6) PLT/cm2, p <0.02). Simvastatin reduced aortic fatty streak surface coverage (31,7+/-5.3%) vs. controls (47.9+/-4.1%, p <0.005) and intimal thickening in thoracic aorta (0.15+/-0.05 intima to total area ratio in simvastatin treated animals vs. 0.36+/-0.03 in control animals, p <0.05). Atherosclerotic fatty streak coverage correlated positively with total cholesterol, tryglicerides and LDL-cholesterol levels in all groups. HMG-CoA reductase inhibitors similarly lowered plasma lipids but exhibited significantly different effects in the modulation of atherosclerotic development and platelet response at the tested dose. Therefore, the effect of statins on the progression and manifestation of cardiovascular disease might be also mediated by regulating platelet response to vessel injury.

Animals↗
PubMed1999

The utility of animal models in the preclinical study of interventions to prevent human coronary artery restenosis: analysis and recommendations. On behalf of the Subcommittee on Animal, Cellular and Molecular Models of Thrombosis and Haemostasis of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis.

Small animal models have several advantageous characteristics, but those used in preclinical restenosis research have lacked efficacy in predicting the success of interventions to inhibit restenosis in humans. Large animal models have been more successful than small animal models in predicting efficacy of interventions to inhibit restenosis in humans, but the results of studies carried out with these models have not been uniformly predictive. Confirmation of the results of small animal studies in large animals has not always yielded information predictive of success in humans; however, the absence of such confirmation has had strong negative predictive value. Small animal models used for evaluation of interventions to inhibit luminal narrowing following arterial instrumentation have failed to closely simulate human atherosclerosis and the stenotic lesions subjected to instrumentation in humans. Transgenic, atherosclerotic animals hold promise for the development of more useful small animal models to study mechanisms of the response of diseased arteries to angioplasty and stents. The pig has been the most useful large animal to study stenosis/ restenosis, but more information is needed to overcome the limitations of this model.

Animals↗