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Localized States in Active Fluids. PHYSICAL REVIEW LETTERS 2023; 131:238401. [PMID: 38134762 DOI: 10.1103/physrevlett.131.238401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/13/2023] [Indexed: 12/24/2023]
Abstract
Biological active matter is typically tightly coupled to chemical reaction networks affecting its assembly-disassembly dynamics and stress generation. We show that localized states can emerge spontaneously if assembly of active matter is regulated by chemical species that are advected with flows resulting from gradients in the active stress. The mechanochemical localized patterns form via a subcritical bifurcation and for parameter values for which patterns do not exist in absence of the advective coupling. Our work identifies a generic mechanism underlying localized cellular patterns.
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Epithelial cells adapt to curvature induction via transient active osmotic swelling. Dev Cell 2022; 57:1257-1270.e5. [PMID: 35568030 PMCID: PMC9165930 DOI: 10.1016/j.devcel.2022.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 02/11/2022] [Accepted: 04/21/2022] [Indexed: 11/29/2022]
Abstract
Generation of tissue curvature is essential to morphogenesis. However, how cells adapt to changing curvature is still unknown because tools to dynamically control curvature in vitro are lacking. Here, we developed self-rolling substrates to study how flat epithelial cell monolayers adapt to a rapid anisotropic change of curvature. We show that the primary response is an active and transient osmotic swelling of cells. This cell volume increase is not observed on inducible wrinkled substrates, where concave and convex regions alternate each other over short distances; and this finding identifies swelling as a collective response to changes of curvature with a persistent sign over large distances. It is triggered by a drop in membrane tension and actin depolymerization, which is perceived by cells as a hypertonic shock. Osmotic swelling restores tension while actin reorganizes, probably to comply with curvature. Thus, epithelia are unique materials that transiently and actively swell while adapting to large curvature induction. Rapid inward and outward epithelial rolling triggers cell volume increase Epithelial folding induces a mechano-osmotic feedback loop that involvs ion channels Cell volume regulation in curved tissues involves actin, membrane tension, and mTORC2
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Local structure of DNA toroids reveals curvature-dependent intermolecular forces. Nucleic Acids Res 2021; 49:3709-3718. [PMID: 33784405 PMCID: PMC8053110 DOI: 10.1093/nar/gkab197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 02/17/2021] [Accepted: 03/12/2021] [Indexed: 01/15/2023] Open
Abstract
In viruses and cells, DNA is closely packed and tightly curved thanks to polyvalent cations inducing an effective attraction between its negatively charged filaments. Our understanding of this effective attraction remains very incomplete, partly because experimental data is limited to bulk measurements on large samples of mostly uncurved DNA helices. Here we use cryo electron microscopy to shed light on the interaction between highly curved helices. We find that the spacing between DNA helices in spermine-induced DNA toroidal condensates depends on their location within the torus, consistent with a mathematical model based on the competition between electrostatic interactions and the bending rigidity of DNA. We use our model to infer the characteristics of the interaction potential, and find that its equilibrium spacing strongly depends on the curvature of the filaments. In addition, the interaction is much softer than previously reported in bulk samples using different salt conditions. Beyond viruses and cells, our characterization of the interactions governing DNA-based dense structures could help develop robust designs in DNA nanotechnologies.
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Abstract
ESCRT-III proteins assemble into ubiquitous membrane-remodeling polymers during many cellular processes. Here we describe the structure of helical membrane tubes that are scaffolded by bundled ESCRT-III filaments. Cryo-ET reveals how the shape of the helical membrane tube arises from the assembly of two distinct bundles of helical filaments that have the same helical path but bind the membrane with different interfaces. Higher-resolution cryo-EM of filaments bound to helical bicelles confirms that ESCRT-III filaments can interact with the membrane through a previously undescribed interface. Mathematical modeling demonstrates that the interface described above is key to the mechanical stability of helical membrane tubes and helps infer the rigidity of the described protein filaments. Altogether, our results suggest that the interactions between ESCRT-III filaments and the membrane could proceed through multiple interfaces, to provide assembly on membranes with various shapes, or adapt the orientation of the filaments towards the membrane during membrane remodeling.
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Conformal Silk-Azobenzene Composite for Optically Switchable Diffractive Structures. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30951-30957. [PMID: 28820237 DOI: 10.1021/acsami.7b09986] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The use of biomaterials as optical components has recently attracted attention because of their ease of functionalization and fabrication, along with their potential use when integrated with biological materials. We present here an observation of the optical properties of a silk-azobenzene material (Azosilk) and demonstrate the operation of an Azosilk/PDMS composite structure that serves as a conformable and switchable optical diffractive structure. Characterization of thermal and isomeric properties of the device, along with its overall performance, is presented in terms of diffractive characteristics and response times. The ease of manufacturing and functionalization opens a promising avenue for rapid device prototyping and interfaces of expanded utility.
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Effect of repeated subcutaneous injections of carbon dioxide (CO2) on inflammation linked to hypoxia in adipose tissue graft. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2015; 19:4501-4506. [PMID: 26698245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE The purposes of this study was to assess the effect of repeated subcutaneous injections of CO2 on adipose tissue graft survival in immunosuppressed female nude mice. The authors designed an experimental study using volume measures, histopathological analysis and nuclear magnetic resonance of fat graft. The effect of repeated subcutaneous injection of CO2 is not yet investigated MATERIALS AND METHODS Approximately 0.5 ml of human fat were transplanted in a group of female nude mice. The mice were treated with 3 injections of 80 µl each carbon dioxide (total 240 µl) for 7 weeks. Initially, in vivo measurements were conducted and subsequently a comprehensive histopathological analysis was performed. RESULTS The presence of inflammation was graded absent to minimal in animals treated with CO2 while a minimal to moderate grade was assigned to the control group. CONCLUSIONS CO2 injection enhances the inflammatory response of the implanted tissue and reduces the reabsorption rate. The treatment may improve the graft survival in a more prolonged time-frame.
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Lifelong physical exercise delays age-associated skeletal muscle decline. J Gerontol A Biol Sci Med Sci 2014; 70:163-73. [PMID: 24550352 DOI: 10.1093/gerona/glu006] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Aging is usually accompanied by a significant reduction in muscle mass and force. To determine the relative contribution of inactivity and aging per se to this decay, we compared muscle function and structure in (a) male participants belonging to a group of well-trained seniors (average of 70 years) who exercised regularly in their previous 30 years and (b) age-matched healthy sedentary seniors with (c) active young men (average of 27 years). The results collected show that relative to their sedentary cohorts, muscle from senior sportsmen have: (a) greater maximal isometric force and function, (b) better preserved fiber morphology and ultrastructure of intracellular organelles involved in Ca(2+) handling and ATP production, (c) preserved muscle fibers size resulting from fiber rescue by reinnervation, and (d) lowered expression of genes related to autophagy and reactive oxygen species detoxification. All together, our results indicate that: (a) skeletal muscle of senior sportsmen is actually more similar to that of adults than to that of age-matched sedentaries and (b) signaling pathways controlling muscle mass and metabolism are differently modulated in senior sportsmen to guarantee maintenance of skeletal muscle structure, function, bioenergetic characteristics, and phenotype. Thus, regular physical activity is a good strategy to attenuate age-related general decay of muscle structure and function (ClinicalTrials.gov: NCT01679977).
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Signalling pathways regulating muscle mass in ageing skeletal muscle. The role of the IGF1-Akt-mTOR-FoxO pathway. Biogerontology 2013; 14:303-23. [DOI: 10.1007/s10522-013-9432-9] [Citation(s) in RCA: 237] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 05/03/2013] [Indexed: 11/29/2022]
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Ocular manifestations in Kniest syndrome, Smith-Lemli-Opitz syndrome, Hallermann-Streiff-François syndrome, Rubinstein-Taybi syndrome and median cleft face syndrome. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/13816818509004126] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Retinopathy induced by drugs and herbal medicines. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2008; 12:293-298. [PMID: 19024212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Retina is the part of the eye suffering most damage from drugs. It is made up of a thin nervous membrane that covers the eye-ball internally, within the thickness of which three types of cells are ordered. In this paper we describe the drugs that are responsible for retinal side effects. Most commonly recognized drugs-induced retinopathy have a particular affinity for the retinal pigmented epithelium: antimalarials (quinine, hydroxychloroquine, mefloquine), phenothiazines, indomethacin, ethambutol, and desferrioxamine. Attention is especially focused on drugs more recently suspected of adverse reactions in the retina: vigabatrin, gabapentin, sildenafil, tamoxifen, isotretinoin, interferon, and omeprazole. Moreover, we referred some reports of retinopathy by herbal medicines and nutritional supplements (canthaxanthine, Gingko biloba L. and Glycyrrhiza glabra L.) This review is based on data published in scientific journals indexed by the PubMed and Medline databases. The last search of the literature was conducted in April 2008.
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Stem cell-mediated muscle regeneration and repair in aging and neuromuscular diseases. Eur J Histochem 2007; 51 Suppl 1:35-43. [PMID: 17703592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
One of the most exciting aspirations of current medical science is the regeneration of damaged body parts. The capacity of adult tissues to regenerate in response to injury stimuli represents an important homeostatic process that until recently was thought to be limited in mammals to tissues with high turnover such as blood and skin. However, it is now generally accepted that each tissue type, even those considered post-mitotic, such as nerve or muscle, contains a reserve of undifferentiated progenitor cells, loosely termed stem cells, participating in tissue regeneration and repair. Skeletal muscle regeneration is a coordinate process in which several factors are sequentially activated to maintain and preserve muscle structure and function upon injury stimuli. In this review, we will discuss the role of stem cells in muscle regeneration and repair and the critical role of specific factors, such as IGF-1, vasopressin and TNF-alpha, in the modulation of the myogenic program and in the regulation of muscle regeneration and homeostasis.
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Abstract
We have examined the murine genes encoding transcription factors E2F1, -3, -5 and -6 in gametes and early embryos. All genes are expressed as maternal transcripts and all are efficiently transcribed after the blastocyst stage. Between those two stages, each E2F mRNA is transcribed with a distinctive and unique pattern. E2F proteins are also differentially expressed and compartmentalized in pre-implantation embryos.
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Abstract
We have tested three parameters in sperm-mediated gene transfer assays with mice and pigs: (i) the epididymal versus ejaculated origin of sperm cells, (ii) the primary structure, and (iii) the amount of the challenging foreign DNA. We have found that the pVLCNhGH construct, of retrotransposon origin, causes a massive embryo lethality and yet increases the yield of genetic transformation among born animals of both species compared to viral constructs. Arrest of embryonic development is a DNA dose-dependent effect, which is observed with high DNA doses, while lower doses are compatible with development. Finally, the overall efficiency of sperm-mediated gene transfer is higher when ejaculated, versus epididymal, spermatozoa are used. We suggest that this difference is related to the highly efficient apoptotic response in epididymal compared to ejaculated spermatozoa, triggered by the interaction of exogenous DNA molecules with the sperm membrane.
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Abstract
Endothelium is an early target of pro-atherosclerotic events, which may result in functional and morphological perturbations. Oxidized low density lipoproteins, an atherogenic factor with strong cytotoxicity, may potentially contribute to altered endothelial function through the activation of a stress response, which would rescue cells to full vitality, or, conversely, by leading to cell death. Evidence is presented here for the ability of chemically oxidized low density lipoproteins to induce the synthesis of the inducible form of heat shock protein 70 in cultured human endothelial cells, and for the association of epitopes of these modified lipoproteins with apoptotic endothelial cells in aortic sections from hypercholesterolemic rabbits.
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Effect of lercanidipine and its (R)-enantiomer on atherosclerotic lesions induced in hypercholesterolemic rabbits. Br J Pharmacol 1998; 125:1471-6. [PMID: 9884075 PMCID: PMC1565732 DOI: 10.1038/sj.bjp.0702221] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The in vivo antiatherogenic activity of the calcium antagonist lercanidipine and its (R)-enantiomer was investigated in two different types of atherosclerotic lesions (hyperplastic and fatty-streak lesions) in rabbits. Lercanidipine (0.3, 1, and 3 mg kg(-1) week(-1)) as well as its (R)-enantiomer at 3 mg kg(-1) week(-1) were given by subcutaneous injection for 10 weeks to White New Zealand rabbits, with cholesterol feeding beginning at week 2. The hyperplastic lesion was obtained by positioning a hollow silastic collar around one carotid artery, while aortic fatty streak lesions were induced by cholesterol feeding. In untreated animals (n=5), 14 days after collar positioning an intimal hyperplasia was clearly detectable: the arteries without collar showed a intima/media (I/M) ratio of 0.03+/-0.02, whereas in carotids with a collar the ratio was 2+/-0.42. In lercanidipine-treated animals a significant and dose-dependent effect on intimal hyperplasia was observed. I/M ratios were 0.73+/-0.4, 0.42+/-0.1, 0.32+/-0.1 for 0.3, 1, and 3 mg kg(-1) week(-1), respectively (P<0.05). The lercanidipine enantiomer (3 mg kg(-1) week(-1)) was as effective as the racemate (0.41+/-0.11). Proliferation of smooth muscle cells, assessed by incorporation of BrdU into DNA, was reduced by about 50%, 70%, 85%, and 80% by lercanidipine (0.3, 1, and 3 mg kg(-1) week(-1)) and its (R)-enantiomer, respectively. The area of fatty-streaks in the aorta (n = 11-15) was significantly reduced by lercanidipine (3 mg kg(-1) week(-1), 16% vs 27%, P<0.05), a trend was observed also with lower doses. When different segments of the aorta were considered (arch, thoracic, abdominal) a significant and dose-dependent effect in the thoracic and abdominal aorta was observed also at lower doses. The (R)-enantiomer was as effective as lercanidipine. These results suggest a direct antiatherosclerotic effect of lercanidipine, independent of modulation of risk factors such as hypercholesterolemia and/or hypertension as demonstrated by the absence of stereoselectivity.
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Dual effects of the antioxidant agents probucol and carvedilol on proliferative and fatty lesions in hypercholesterolemic rabbits. Atherosclerosis 1998; 141:45-51. [PMID: 9863537 DOI: 10.1016/s0021-9150(98)00146-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The in vivo direct antiatherogenic activity of the antioxidant probucol (200 mg/kg per day) or the beta-blocker with antioxidant properties carvedilol (10 and 20 mg/kg per day) was tested in the same animal in two different types of atherosclerotic lesion (proliferative and fatty lesions) induced in cholesterol-fed rabbits (1%). Drugs were given daily mixed with standard diet for 8 weeks; body weight and plasma lipid profile were not different among groups throughout the study. Aortic fatty lesions were induced by cholesterol feeding (n = 25 in each group) and their extent expressed as % of aorta inner surface covered by plaques was significantly reduced by both drugs (28.2+/-9.6%, P <0.05, 19.9+/-6.2%, P <0.01 for low- and high-dose carvedilol, respectively; 22.3+/-7.6%, P <0.01 for probucol, versus 41.6+/-10.7% in control rabbits). Proliferative lesions were obtained by positioning a hollow silastic collar around one carotid artery 6 weeks after dietary and drug treatments started (n = 5 in each group). The neointimal formation, mostly composed by myocytes, was determined by measuring cross-sectional thickness ratio of intimal (I) and medial (M) tissue of fixed arteries. In untreated animals, collared arteries resulted in a significant neointimal cell accumulation compared to the sham (1.10+/-0.14 versus 0.02+/-0.01) without change in medial thickness. I/M ratio was reduced by about 50% in animals treated with probucol (0.51+/-0.1) and carvedilol (0.66+/-0.21 and 0.52+/-0.1 in the low- and high-dose group, respectively). Total plasma TBARS were more than 50% lower in both probucol- and high-dose carvedilol-treated rabbits. Results show that pharmacological pretreatment with antioxidants directly inhibits early atherogenic processes, representing a potentially useful approach in the prevention of atherosclerosis.
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Abstract
The renin-angiotensin system is an important modulator of arterial blood pressure and inhibitors of the angiotensin-converting enzyme (ACE-Is) and are currently used in the treatment of hypertension. The pleiotropic actions exerted by angiotensin II (AngII) on the functionality of the vessel wall may have pro-atherosclerotic outcomes; evidence for an anti-atherosclerotic effect of ACE-Is has been presented and an antioxidant effect has been attributed to thiol-containing ACE-Is, like Captopril. The present study has been undertaken to investigate the effect of Delapril, a lipophilic ACE-I, on the development of atherosclerosis in cholesterol-fed rabbits. While it did not correct hyperlipidemia, Delapril dose dependently inhibited the development of atherosclerosis, expressed as aortic area covered by lesions (23.3+/-4.1, 21.3+/-2.4 and 18.5+/-3.3% with Delapril at the daily dose of 5, 10 and 20 mg/kg, respectively, versus 38.2%+/-6.4 for control animals) and its effect was similar to that of Captopril (14.5+/-5.1% at the daily dose of 25 mg/kg). Furthermore, Delapril partially and dose dependently restored endothelium-dependent relaxation, which is impaired in vessels from hypercholesterolemic animals (51.80+/-12.18, 59.74+/-5.16, 69.13+/-8.70 maximal percent relaxation versus 48.26+/-3.05% for the untreated control and 67.67+/-6.72% for Captopril-treated animals). An antioxidant mechanism is unlikely to explain this data, since Delapril does not contain thiol groups. These observations suggest that Delapril may represent an effective pharmacological approach for the treatment of atherosclerosis during its early phases.
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MESH Headings
- Angiotensin-Converting Enzyme Inhibitors/administration & dosage
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Angiotensin-Converting Enzyme Inhibitors/therapeutic use
- Animals
- Aorta, Abdominal/drug effects
- Aorta, Abdominal/pathology
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/pathology
- Arteriosclerosis/chemically induced
- Arteriosclerosis/drug therapy
- Arteriosclerosis/pathology
- Body Weight/drug effects
- Captopril/administration & dosage
- Captopril/pharmacology
- Cholesterol/blood
- Cholesterol, Dietary/administration & dosage
- Cholesterol, HDL/blood
- Cholesterol, HDL/drug effects
- Data Interpretation, Statistical
- Diet, Atherogenic
- Disease Models, Animal
- Disease Progression
- Dose-Response Relationship, Drug
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiopathology
- Hypercholesterolemia/chemically induced
- Hypercholesterolemia/drug therapy
- Hypercholesterolemia/pathology
- Indans/administration & dosage
- Indans/pharmacology
- Indans/therapeutic use
- Male
- Nitric Oxide/metabolism
- Nitroglycerin/administration & dosage
- Nitroglycerin/pharmacology
- Norepinephrine/administration & dosage
- Norepinephrine/pharmacology
- Rabbits
- Triglycerides/blood
- Vasoconstrictor Agents/administration & dosage
- Vasoconstrictor Agents/pharmacology
- Vasodilation/drug effects
- Vasodilator Agents/administration & dosage
- Vasodilator Agents/pharmacology
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Abstract
1. The in vivo antiatherogenic activity of the calcium antagonist, lacidipine, was investigated in two different types of atherosclerotic lesions (proliferative and fatty lesions) induced in rabbits. 2. The proliferative lesion was obtained by positioning a hollow silastic collar around one carotid artery, while aortic fatty lesions were induced by cholesterol feeding. Cholesterol (1%) and lacidipine (1, 3, and 10 mg kg-1) were given daily mixed with standard diet for 8 weeks to White New Zealand rabbits. The intimal hyperplasia (proliferative lesion) was induced 6 weeks after dietary and drug treatment started. 3. The neointimal formation was determined by measuring cross sectional thickness of intimal (I) and medial (M) tissue of fixed arteries. In untreated animals (n = 5), 14 days after collar positioning an intimal hyperplasia was clearly detectable: the arteries with no collar (sham) showed an I/M tissue ratio of 0.03 +/- 0.02, whereas in the carotid with collar the ratio was 0.62 +/- 0.12. In lacidipine-treated animals a significant and dose-dependent effect on proliferative lesions at all three doses tested, was observed. I/M ratios were 0.47 +/- 0.02, 0.40 +/- 0.09, 0.32 +/- 0.02 for doses 1, 3, and 10 mg kg-1 day-1, respectively (P < 0.05). 4. The fatty lesion extent was significantly reduced by lacidipine at the 10 mg kg-1 day-1 dose, although a trend was also observed with lower dosage. 5. These results suggest a direct antiatherosclerotic effect of lacidipine, independent of modulation of risk factors such as hypercholesterolaemia and/or hypertension. Furthermore, the proliferative lesions are apparently more sensitive to lacidipine than are lipid-rich lesions.
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Abstract
The in vivo antiatherogenic activity of the calcium antagonist lacidipine was investigated in arterial hyperplasia induced by perivascular manipulation of hypercholesterolemic carotid rabbits. This was accomplished by positioning a hollow silastic collar around one carotid, which within a few days induces an atherosclerotic lesion (proliferative lesion) showing biochemical and morphologic changes similar to those of early human atherosclerosis: the contralateral carotid, with no collar, served as control in the same animal. The effect of lacidipine was also investigated in aortic atherosclerotic lesions (fatty lesions) induced by hypercholesterolemia mixed with either cholesterol (1%) and lacidipine (3 mg/kg/day) or cholesterol (1%) alone for 8 weeks. Hypercholesterolemic New Zealand White rabbits were fed daily a standard diet. Intimal hyperplasia was mechanically induced in one carotid artery of each rabbit 6 weeks after dietary and drug treatment started. Neointimal formation was followed by measuring by light microscopy the cross-sectional thickness of intimal (I) and medial (M) tissue of fixed arteries. In positive control animals receiving dietary cholesterol only (n = 10), by 14 d after collar positioning the process of intimal hyperplasia was significantly pronounced. The control arteries showed an I:M tissue ratio of 0.03 +/- 0.02, whereas in the carotid with collar the ratio was 0.56 +/- 0.11. In the animals receiving lacidipine, neointimal formation was significantly lower [I:M tissue ratio 0.32 +/- 0.1 (n = 10), about 60% of positive controls]. Measurement of the percent area of the aortic intima covered by plaques did not show significant differences between control and lacidipine-treated animals. These results suggest a direct antiatherosclerotic effect of lacidipine on proliferative lesions.
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Abstract
SIM 6080 is a new calcium antagonist, structurally related to diphenylalkylamines, which combines transmembrane and intracellular calcium antagonist activities. In the present study we investigated the effect of SIM 6080 on atherogenesis in cholesterol-fed rabbits. Subcutaneous administration of the compound at 0.33, 1, and 3 mg kg-1/bid for 60 days neither affected plasma lipids nor blood pressure. However at 1 and 3 mg kg-1/bid SIM 6080 reduced in a dose-dependent manner both the area of the aorta covered by plaques and aortic cholesterol content. Determination of SIM 6080 plasma and aortic content indicated that the compound could concentrate up to 10 times in the arterial tissue. In vitro studies demonstrated that at concentrations similar to those observed in the aorta this compound may stimulate rabbit beta VLDL catabolism by smooth muscle cells in an homologous system suggesting that the up-regulation of LDL-receptors in the aorta may contribute to the antiatherosclerotic properties of SIM 6080.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/pathology
- Arteriosclerosis/drug therapy
- Arteriosclerosis/pathology
- Calcium Channel Blockers/blood
- Calcium Channel Blockers/therapeutic use
- Cells, Cultured
- Cholesterol/metabolism
- Cholesterol, Dietary/pharmacology
- Diet, Atherogenic
- Ethylenediamines/blood
- Ethylenediamines/therapeutic use
- Lipids/blood
- Lipoproteins, VLDL/blood
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Rabbits
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Eye involvement in sarcoidosis: survey of 197 patients. SARCOIDOSIS 1993; 10:158-9. [PMID: 8140313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Unusual optic nerve lesion in sarcoidosis. SARCOIDOSIS 1991; 8:72-4. [PMID: 1669946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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23
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Ocular manifestations in Kniest syndrome, Smith-Lemli-Opitz syndrome, Hallermann-Streiff-François syndrome, Rubinstein-Taybi syndrome and median cleft face syndrome. OPHTHALMIC PAEDIATRICS AND GENETICS 1985; 6:343-7. [PMID: 3934624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In the pathology of malformations it is only in very few cases possible to identify a complete syndromal picture; the authors present some multimalformative syndromes, observed in the past few years at the Department of Pediatric Ophthalmology of the University of Siena. The ocular findings are reported and discussed in relation with the general features in order to make a correct diagnosis.
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Abstract
Some cases of complete Aicardi's syndrome (agenesis of the corpus callosum, infantile spasmus, mental retardation, costovertebral anomalies and a characteristic lacunar chorioretinopathy) are reported together with other unusual cases (isolated lacunar chorioretinopathy).
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Abstract
The authors give a résumé of the main clinical characteristics of Leber's disease with presentation of pedigrees of three affected families.
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Anterior optic pathways gliomas. The dilemma of treatment. J Neurosurg Sci 1982; 26:61-72. [PMID: 6815314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Anterior optic pathways gliomas are classifiable histologically and clinically with other pilocytic gliomas of the midline (of hypothalamus and brainstem), especially of childhood. The very slow course, sometimes imperceptible over the years, that characterizes the majority of them should not be taken to mean lack of growth. Tumultuous courses and acute episodic deteriorations are both possible. Hence the need for therapy. Indefinite abstention cannot be upheld, at least in the great majority of cases. In gliomas of a nerve only the object of surgery is usually removal, using the intraorbital, intracanalicular and intracranial approaches, but in gliomas of the chiasm or chiasm-hypothalamus the object is more exploratory and decompressive. Radiotherapy is generally accepted as affective only in the latter cases. No single standard protocol is possible: treatment had to be individualized case by case.
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Medical therapy of retinoblastoma in children. J Neurosurg Sci 1982; 26:49-52. [PMID: 7143085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Retinoblastoma is the most common ocular tumour which occurs in infancy. Unfortunately, it is diagnosed only when the disease is in an advanced phase and the prognosis is decidedly unfavorable. Patients treated early, in the first stage of the disease can be cured with surgical and radiation treatment. For patients who are already in an advanced stage, the risk of metastatic dissemination is very high and therefore the introduction of chemotherapy, particularly vincristine and cyclophosphamide is believed to be useful. The authors report on their results obtained in patients with retinoblastoma who have been treated with combined surgical, radio- and chemotherapic treatment.
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Medical therapy of orbit rhabdomyosarcoma in children. J Neurosurg Sci 1982; 26:45-8. [PMID: 7143084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Rhabdomyosarcoma is the most frequent malignant tumour of the orbit in the pediatric age. The chances of survival of patients affected by such a highly malignant neoplasia have significantly improved in recent years. The results obtained up until now with various therapeutic approaches are reviewed briefly and the results obtained in four children affected by rhabdomyosarcoma of the orbit are reported who were treated at the Ophthalmology and Pediatric Clinics of Siena University. The possibility is advanced that the less aggressive and a cautiously conservative treatment can produce the equivalent excellent results which are presently obtained by very destructive therapeutic approaches.
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