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Caiazza C, Preziosi V, Tomaiuolo G, O'Sullivan D, Guida V, Guido S. Flow-induced concentration gradients in shear-banding of branched wormlike micellar solutions. J Colloid Interface Sci 2019; 534:695-703. [DOI: 10.1016/j.jcis.2018.09.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 11/29/2022]
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Abstract
Surfactant solutions exhibit multilamellar surfactant vesicles (MLVs) under flow conditions and in concentration ranges which are found in a large number of industrial applications. MLVs are typically formed from a lamellar phase and play an important role in determining the rheological properties of surfactant solutions. Despite the wide literature on the collective dynamics of flowing MLVs, investigations into the flow behavior of single MLVs are scarce. In this work, we investigate a concentrated aqueous solution of linear alkylbenzene sulfonic acid (HLAS), characterized by MLVs dispersed in an isotropic micellar phase. Rheological tests show that the HLAS solution is a shear-thinning fluid with a power law index dependent on the shear rate. Pressure-driven shear flow of the HLAS solution in glass capillaries is investigated using high-speed video microscopy and image analysis. The so obtained velocity profiles provide evidence for a power-law fluid behaviour of the HLAS solution and images show a flow-focusing effect of the lamellar phase in the central core of the capillary. The flow behavior of individual MLVs shows analogies with that of unilamellar vesicles and emulsion droplets. Deformed MLVs exhibit typical shapes of unilamellar vesicles, such as parachute and bullet-like. Furthermore, MLV velocity follows the classical Hetsroni theory for droplets provided that the power law shear dependent viscosity of the HLAS solution is taken into account. The results of this work are relevant for the processing of surfactant-based systems in which the final properties depend on the flow-induced morphology, such as cosmetic formulations and food products.
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Affiliation(s)
- A Pommella
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale (DICMAPI) Università di Napoli Federico II, P.le Tecchio, 80, 80125 Napoli, Italy.
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Tosco A, De Gregorio F, Esposito S, De Stefano D, Sana I, Ferrari E, Sepe A, Salvadori L, Buonpensiero P, Di Pasqua A, Grassia R, Leone CA, Guido S, De Rosa G, Lusa S, Bona G, Stoll G, Maiuri MC, Mehta A, Kroemer G, Maiuri L, Raia V. A novel treatment of cystic fibrosis acting on-target: cysteamine plus epigallocatechin gallate for the autophagy-dependent rescue of class II-mutated CFTR. Cell Death Differ 2016; 24:1305. [PMID: 27447111 DOI: 10.1038/cdd.2016.43] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
This corrects the article DOI: 10.1038/cdd.2016.22.
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Tosco A, De Gregorio F, Esposito S, De Stefano D, Sana I, Ferrari E, Sepe A, Salvadori L, Buonpensiero P, Di Pasqua A, Grassia R, Leone CA, Guido S, De Rosa G, Lusa S, Bona G, Stoll G, Maiuri MC, Mehta A, Kroemer G, Maiuri L, Raia V. A novel treatment of cystic fibrosis acting on-target: cysteamine plus epigallocatechin gallate for the autophagy-dependent rescue of class II-mutated CFTR. Cell Death Differ 2016; 23:1380-93. [PMID: 27035618 PMCID: PMC4947669 DOI: 10.1038/cdd.2016.22] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/25/2016] [Accepted: 01/27/2016] [Indexed: 12/30/2022] Open
Abstract
We previously reported that the combination of two safe proteostasis regulators, cysteamine and epigallocatechin gallate (EGCG), can be used to improve deficient expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in patients homozygous for the CFTR Phe508del mutation. Here we provide the proof-of-concept that this combination treatment restored CFTR function and reduced lung inflammation (P<0.001) in Phe508del/Phe508del or Phe508del/null-Cftr (but not in Cftr-null mice), provided that such mice were autophagy-competent. Primary nasal cells from patients bearing different class II CFTR mutations, either in homozygous or compound heterozygous form, responded to the treatment in vitro. We assessed individual responses to cysteamine plus EGCG in a single-centre, open-label phase-2 trial. The combination treatment decreased sweat chloride from baseline, increased both CFTR protein and function in nasal cells, restored autophagy in such cells, decreased CXCL8 and TNF-α in the sputum, and tended to improve respiratory function. These positive effects were particularly strong in patients carrying Phe508del CFTR mutations in homozygosity or heterozygosity. However, a fraction of patients bearing other CFTR mutations failed to respond to therapy. Importantly, the same patients whose primary nasal brushed cells did not respond to cysteamine plus EGCG in vitro also exhibited deficient therapeutic responses in vivo. Altogether, these results suggest that the combination treatment of cysteamine plus EGCG acts 'on-target' because it can only rescue CFTR function when autophagy is functional (in mice) and improves CFTR function when a rescuable protein is expressed (in mice and men). These results should spur the further clinical development of the combination treatment.
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Affiliation(s)
- A Tosco
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - F De Gregorio
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - S Esposito
- European Institute for Research in Cystic Fibrosis, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - D De Stefano
- European Institute for Research in Cystic Fibrosis, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - I Sana
- European Institute for Research in Cystic Fibrosis, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - E Ferrari
- European Institute for Research in Cystic Fibrosis, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - A Sepe
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - L Salvadori
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - P Buonpensiero
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - A Di Pasqua
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
| | - R Grassia
- Otorhinolaryngology Unit, Monaldi Hospital, Naples 80131, Italy
| | - C A Leone
- Otorhinolaryngology Unit, Monaldi Hospital, Naples 80131, Italy
| | - S Guido
- Department of Chemical, Materials and Production Engineering; Federico II University, Naples, Italy
| | - G De Rosa
- Department of Pharmacy, School of Pharmacy, Federico II University, Naples 80131, Italy
| | - S Lusa
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples 80138, Italy
| | - G Bona
- SCDU of Pediatrics, Department of Health Sciences, University of Piemonte Orientale, Novara 28100, Italy
| | - G Stoll
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Equipe 11 labellisée Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France.,Institut National de la Santé et de la Recherche Médicale, Paris, France.,Université Pierre et Marie Curie, Paris, France
| | - M C Maiuri
- Equipe 11 labellisée Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France
| | - A Mehta
- Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - G Kroemer
- Equipe 11 labellisée Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France.,INSERM U1138, Centre de Recherche des Cordeliers, Paris, France.,Université Paris Descartes, Paris, France.,Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif, France.,Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France.,Karolinska Institute, Department of Women's and Children's Health, Karolinska University Hospital, Stockholm 17176, Sweden
| | - L Maiuri
- European Institute for Research in Cystic Fibrosis, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy.,SCDU of Pediatrics, Department of Health Sciences, University of Piemonte Orientale, Novara 28100, Italy
| | - V Raia
- Regional Cystic Fibrosis Center, Pediatric Unit, Department of Translational Medical Sciences, Federico II University, Naples 80131, Italy
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Vilaça LF, Diniz WJ, Melo TF, Oliveira JC, Guido S, Brito CEVL, Costa NA, Santoro KR. Polimorfismos do gene BoLA-DRB3 em rebanhos bovinos leiteiros 5/8 Girolando e Holandês no estado de Pernambuco. ARCH ZOOTEC 2016. [DOI: 10.21071/az.v65i249.435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A região BoLA (Bovine Lymphocyte Antigen) tem recebido atenção por seus alelos terem ação sobre funções imunológicas e características de produção. O presente estudo teve por objetivo a identificação e associação dos polimorfismos do gene BoLA-DRB3.2 em 145 vacas leiteiras 5/8 Girolando e Holandês, em rebanhos de referência no Estado de Pernambuco. Identificaram-se 39 alelos com frequências alélicas variando entre 0,42 e 15,97 %, sendo os alelos mais frequentes 0101 (6,13 %), R (14,11 %) e 1101 (14,72 %). Verificaram-se valores baixos de similaridade, demonstrando maior variabilidade genética entre os animais. A estimativa de distância entre os rebanhos Holandês e 5/8 Girolando, foi de 0,075. A heterozigosidade observada (Ho) apresentou valores menores que a heterozigosidade esperada (He). Observou-se um elevado polimorfismo do gene BoLA-DRB3.2 para os rebanhos estudados e um elevado número de alelos que desempenharam efeitos positivos na produção de leite, com destaque para os alelos 16 e 0101.
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Liuzzi R, Gallier S, Ringler S, Caserta S, Guido S. Visualization of choline-based phospholipids at the interface of oil/water emulsions with TEPC-15 antibody. Immunofluorescence applied to colloidal systems. RSC Adv 2016. [DOI: 10.1039/c6ra13775j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Phospholipids, which are amphiphilic biomolecules composed of a polar head group and two nonpolar fatty acid tails, play a central role in cellular and body functions.
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Affiliation(s)
- R. Liuzzi
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale (DICMAPI)
- Università di Napoli Federico II
- Napoli
- Italy
| | - S. Gallier
- Danone Nutricia Research
- Utrecht 3584 CT
- The Netherlands
| | - S. Ringler
- Danone Nutricia Research
- Utrecht 3584 CT
- The Netherlands
| | - S. Caserta
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale (DICMAPI)
- Università di Napoli Federico II
- Napoli
- Italy
- Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM)
| | - S. Guido
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale (DICMAPI)
- Università di Napoli Federico II
- Napoli
- Italy
- Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM)
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7
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Posocco P, Perazzo A, Preziosi V, Laurini E, Pricl S, Guido S. Interfacial tension of oil/water emulsions with mixed non-ionic surfactants: comparison between experiments and molecular simulations. RSC Adv 2016. [DOI: 10.1039/c5ra24262b] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Smaller Span molecules occupy the free spaces between bulkier Tween molecules thus lowering interfacial tension as compared to those obtained for single surfactant systems.
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Affiliation(s)
- P. Posocco
- Molecular Simulation Engineering Laboratory (MOSE)
- Department of Engineering and Architecture (DEA)
- University of Trieste
- 34127 Trieste
- Italy
| | - A. Perazzo
- Department of Chemical
- Materials and Production Engineering
- University of Napoli Federico II
- 80125 Napoli
- Italy
| | - V. Preziosi
- Department of Chemical
- Materials and Production Engineering
- University of Napoli Federico II
- 80125 Napoli
- Italy
| | - E. Laurini
- Molecular Simulation Engineering Laboratory (MOSE)
- Department of Engineering and Architecture (DEA)
- University of Trieste
- 34127 Trieste
- Italy
| | - S. Pricl
- Molecular Simulation Engineering Laboratory (MOSE)
- Department of Engineering and Architecture (DEA)
- University of Trieste
- 34127 Trieste
- Italy
| | - S. Guido
- Department of Chemical
- Materials and Production Engineering
- University of Napoli Federico II
- 80125 Napoli
- Italy
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Perazzo A, Preziosi V, Guido S. Phase inversion emulsification: Current understanding and applications. Adv Colloid Interface Sci 2015; 222:581-99. [PMID: 25632889 DOI: 10.1016/j.cis.2015.01.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 01/05/2015] [Accepted: 01/05/2015] [Indexed: 12/11/2022]
Abstract
This review is addressed to the phase inversion process, which is not only a common, low-energy route to make stable emulsions for a variety of industrial products spanning from food to pharmaceuticals, but can also be an undesired effect in some applications, such as crude oil transportation in pipelines. Two main ways to induce phase inversion are described in the literature, i.e., phase inversion composition (PIC or catastrophic) and phase inversion temperature (PIT or transitional). In the former, starting from one phase (oil or water) with surfactants, the other phase is more or less gradually added until it reverts to the continuous phase. In PIT, phase inversion is driven by a temperature change without varying system composition. Given its industrial relevance and scientific challenge, phase inversion has been the subject of a number of papers in the literature, including extensive reviews. Due to the variety of applications and the complexity of the problem, most of the publications have been focused either on the phase behavior or the interfacial properties or the mixing process of the two phases. Although all these aspects are quite important in studying phase inversion and much progress has been done on this topic, a comprehensive picture is still lacking. In particular, the general mechanisms governing the inversion phenomenon have not been completely elucidated and quantitative predictions of the phase inversion point are limited to specific systems and experimental conditions. Here, we review the different approaches on phase inversion and highlight some related applications, including future and emerging perspectives.
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Preziosi V, Tarabella G, D'Angelo P, Romeo A, Barra M, Guido S, Cassinese A, Iannotta S. Real-time monitoring of self-assembling worm-like micelle formation by organic transistors. RSC Adv 2015. [DOI: 10.1039/c4ra14118k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
OECT (Fig. a) for monitoring micelle formation in a spherical (red points – Fig. b) and a wormlike (blue points – Fig. b) regime solutions.
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Affiliation(s)
- V. Preziosi
- CNR-SPIN and Physics Dep
- University Federico II
- I-80125 Naples
- Italy
| | - G. Tarabella
- IMEM-CNR
- Parco Area delle Scienze 37/A
- I-43124 Parma
- Italy
| | - P. D'Angelo
- IMEM-CNR
- Parco Area delle Scienze 37/A
- I-43124 Parma
- Italy
| | - A. Romeo
- IMEM-CNR
- Parco Area delle Scienze 37/A
- I-43124 Parma
- Italy
| | - M. Barra
- CNR-SPIN and Physics Dep
- University Federico II
- I-80125 Naples
- Italy
| | - S. Guido
- Department of Chemical, Materials and Production Engineering
- University Federico II
- I-80125 Naples
- Italy
| | - A. Cassinese
- CNR-SPIN and Physics Dep
- University Federico II
- I-80125 Naples
- Italy
| | - S. Iannotta
- IMEM-CNR
- Parco Area delle Scienze 37/A
- I-43124 Parma
- Italy
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Perazzo A, Tomaiuolo G, Sicignano L, Toscano G, Meadows RE, Nolan SP, Guido S. A microfluidic approach for flexible and efficient operation of a cross-coupling reactive flow. RSC Adv 2015. [DOI: 10.1039/c5ra10971j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Harugeri A, Parthasarathi G, Ramesh M, Guido S, Basavanagowdappa H. Frequency and nature of adverse drug reactions in elderly in-patients of two Indian medical college hospitals. J Postgrad Med 2012; 57:189-95. [PMID: 21941055 DOI: 10.4103/0022-3859.85201] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Adverse drug reactions (ADRs) are a major public health problem in the elderly. Although the Indian elderly represent 12.8% of the entire global elderly population, data on prevalence and predictors of ADRs in elderly Indians is extremely limited. AIM To determine the prevalence, severity, preventability, length of hospital stays, and risk factors for ADRs in hospitalized Indian elderly. SETTING Medicine wards of two tertiary care teaching hospitals. DESIGN Prospective study was conducted between July 2007 and December 2009. MATERIALS AND METHODS In-patients of either sex and aged ≥ 60 years were included and monitored for ADRs throughout their hospital stay. Severity (Hartwig et al. scale), preventability (Shumock and Thornton criteria) and increased length of stay (considering underlying disease, ADR, and discussion with clinicians) were assessed. STATISTICAL ANALYSIS Bivariate analysis and subsequently multivariate logistic regression were used to determine the risk factors for developing ADRs. RESULTS Over the study period, among the 920 patients monitored, 296 patients (32.2%) experienced 419 ADRs. Among all ADRs, 48.4% (203) were preventable. Majority of ADRs [226 (53.9%)] were moderate in severity. Therapeutic classes of drugs frequently associated with ADRs were the drugs used in diabetes [76 (18.1%)] and antibacterials for systemic use [54 (12.9%)]. ADRs increased the hospital stay in 5.9% (54) of patients. Female gender [Odds Ratio: 1.52, 95% Confidence Interval:1.04-2.22, P=0.03] was observed as the influential risk factor for ADRs. CONCLUSION One third of hospitalized elderly experienced ADRs. Interventions focused at preventable ADRs should be developed and implemented to reduce their implications.
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Affiliation(s)
- A Harugeri
- Department of Pharmacy Practice, J.S.S. College of Pharmacy and J.S.S. Medical College Hospital, J.S.S. University, Mysore, India
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Harugeri A, Joseph J, Parthasarathi G, Ramesh M, Guido S. Potentially inappropriate medication use in elderly patients: a study of prevalence and predictors in two teaching hospitals. J Postgrad Med 2010; 56:186-91. [PMID: 20739763 DOI: 10.4103/0022-3859.68642] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Geriatrics is an emerging clinical specialty in India. Information about the appropriateness of prescription medication use among the elderly in India is limited. AIMS To determine the prevalence and predictors of potentially inappropriate medication (PIM) use, and assess the relationship between PIM use and adverse drug reactions (ADRs) in the hospitalized elderly. SETTINGS Medicine wards at two teaching hospitals. DESIGN Prospective observational study. MATERIALS AND METHODS Patients aged > 60 years admitted to medicine wards between January 2008 and June 2009 were included and reviewed for PIM use according to the Beers Criteria 2003 (BC). Severity of PIM use was classified as per BC as 'high' or 'low'. ADRs observed in the study patients were also recorded. STATISTICAL ANALYSIS Association between ADRs and PIM use was assessed using Chi Square test. Bivariate analysis and subsequently multivariate logistic regression was used to identify predictors of PIM use. RESULTS PIM use was observed in 191 of 814 enrolled patients. At least one PIM at admission and during hospital stay was received by 2.4% (20) and 22.1% (180) patients respectively. High-severity PIM use showed a higher prevalence compared to low severity [26.8% (218) vs. 5.5% (45)]. Amongst the patients who received polypharmacy (> or = 5 concurrent medications), 1.4% (5/362) and 22.1% (163/736) patients received PIMs at admission and during hospital stay respectively. Use of aspirin/clopidogrel/diclofenac in the presence of blood clotting disorder or anticoagulant therapy (8.3%) was the most commonly encountered PIM use. Medications not listed in BC were associated with increased occurrence of ADRs compared to medications listed in BC (349 vs. 11) (chi2 =98.4, P<0.001). Increased number of concurrent medications' use (> or = 9) during the stay in medicine wards was identified as an influential predictor of PIM use [Odds ratio: 1.9, 95% Confidence Interval: 1.34-2.69, P<0.001) in the hospitalized elderly. CONCLUSION PIM use was common (23.5%) among the elderly patients during their stay in medicine wards in two tertiary care hospitals. Measures targeted only at BC medications may do little to change the risk of ADRs in elderly.
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Affiliation(s)
- A Harugeri
- Department of Pharmacy Practice, J.S.S. College of Pharmacy and J.S.S. Medical College Hospital, J.S.S. University, Mysore, India
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Jonás A, De Luca AC, Pesce G, Rusciano G, Sasso A, Caserta S, Guido S, Marrucci G. Diffusive mixing of polymers investigated by Raman microspectroscopy and microrheology. Langmuir 2010; 26:14223-14230. [PMID: 20681558 DOI: 10.1021/la101498h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Diffusive mixing in a model polymer blend of limited miscibility (i.e., the pair polydimethylsiloxane/polyisobutene) is investigated. The diffusion process is followed in the actual droplet-based microstructure of the polymer blend, as opposed to the ideal planar geometry used in previous studies (Brochard et al. Macromolecules 1983, 16, 1638; Composto et al. Nature 1987, 328, 234). In our experiments we combine Raman microspectroscopy and video particle-tracking microrheology. The first technique allows us to monitor local concentration of the two polymers with high spatial resolution both inside and outside a micrometer-size droplet of the dispersed phase. In addition, microrheology enables to follow how the local viscosity inside the droplet changes during the diffusion. The polymer viscosity inside the droplet is determined by video tracking the Brownian motion of a polystyrene bead microinjected into the droplet. The microspectroscopic and microrheological data are combined to estimate the concentration dependence of the monomer friction factor of the two species, which is a key parameter to calculate the interdiffusion coefficient D. Numerical calculations based on such concentration-dependent interdiffusion coefficient D and several alternative models of the polymer diffusion are compared to the experimental concentration profiles. A satisfactory agreement is found for the so-called "slow theory" (Brochard et al.). A phenomenological model improving the agreement of the model with the experimental data is also presented.
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Affiliation(s)
- A Jonás
- Institute of Scientific Instruments, Academy of Sciences of the Czech Republic, Kralovopolska 147, CZ-612 64 Brno, Czech Republic
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14
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Affiliation(s)
- A. C. De Luca
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
| | - G. Rusciano
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
| | - G. Pesce
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
| | - S. Caserta
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
| | - S. Guido
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
| | - A. Sasso
- Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Via Cinthia I-80126, Napoli, Italy; CNISM-Consorzio Nazionale interuniversitario per le Scienze Fsiche della Materia UdR, Napoli, Italy; CNR-INFM COHERENTIA, Napoli, Italy; and Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80, I-80125, Napoli, Italy
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D'Angelo P, Barra M, Cassinese A, Guido S, Tomaiuolo G. An Electric Criterion to Evaluate Glass Transition Temperature: Dielectric Relaxation Measurements. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/masy.200750106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Affiliation(s)
- S. Guido
- a Dipartimento di Ingegneria chimica, P.le V. Tecchio , Università degli Studi di Napoli “Federico II” , 80125 , Napoli , Italy
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Sushma M, Noel MV, Ritika MC, James J, Guido S. Cutaneous adverse drug reactions: a 9-year study from a South Indian Hospital. Pharmacoepidemiol Drug Saf 2005; 14:567-70. [PMID: 15937869 DOI: 10.1002/pds.1105] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
PURPOSE To study the clinical spectrum of cutaneous adverse drug reactions (ADRs) in hospitalized patients retrospectively for 9 years and to establish a causal link between the drug and the reaction by using World Health Organization (WHO) causality definitions. MATERIALS AND METHODS A retrospective hospital-based study over a period of 9 years (January 1994 to December 2002) was carried out in the Department of Dermatology of St. John's Medical College Hospital to record various cutaneous ADRs of the hospitalized patients. Based on WHO causality definitions, ADRs were categorized into certain, probable, possible, and unlikely. The data was subjected to descriptive analysis. RESULTS Of the total 3541 patients, 404 (11.4%) were diagnosed as cutaneous ADRs, of which 52% were males and 48% females. A majority of the patients were in the age group of 21-40 years. Only drugs having certain and probable causal association to the reaction were considered for analysis (384). The most common type of ADR was maculopapular rash (42.7%), followed by Stevens-Johnson syndrome (SJS) (19.5%) and fixed drug eruption (11.4%). The drug class implicated was antibiotics (45%), followed by antiepileptics (19%), NSAIDs (19%). The reaction time (RT) recorded was in accordance with the previous reports. CONCLUSION A wide clinical spectrum of cutaneous ADRs ranging from mild maculopapular rash to serious toxic epidermal necrolysis (TEN) were observed. The incidence of life threatening cutaneous ADRs like SJS and TEN were found to be higher compared to studies published abroad. Antibiotics were the most commonly implicated drugs. A higher number of cutaneous ADRs were found to newer drugs like cephalosporins and fluroquinolones compared to previous studies.
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Affiliation(s)
- M Sushma
- Department of Pharmacology, St. John's Medical College, Bangalore, India.
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Devi DP, Sushma M, Guido S. Drug-induced upper gastrointestinal disorders requiring hospitalization: a five-year study in a South Indian hospital. Pharmacoepidemiol Drug Saf 2005; 13:859-62. [PMID: 15386699 DOI: 10.1002/pds.988] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To study the clinical spectrum of drug induced upper gastrointestinal tract (GIT) disorders requiring hospitalization and establish the causal relation between drug and disorder using WHO causality definitions. METHODS Case-records of patients in the Department of Gastroenterology (from January 1998 to December 2002) hospitalized with diagnoses of drug induced upper GIT disorders were analyzed retrospectively. The causality assessment of each disorder was done based on WHO causality definitions. RESULTS Out of 101 cases identified over the study period, 8 were categorized as certain, 87 as probable and 6 cases as possible. The certain and probable cases (95) were analyzed. Of these, 13 were in 1998, 14 in 1999, 18 in 2000, 20 in 2001 and 30 in 2002. The drug class most commonly implicated with adverse drug reactions was non-steroidal anti-inflammatory drugs (NSAIDs) (76.8%). Among individual drugs, aspirin was most commonly involved (32.6%). Results of endoscopy revealed gastric erosions (40.2%), combination of gastric ulcer and gastric erosions (16.1%), gastric ulcer (15.0%), duodenal ulcer (13.8%), normal (13.8%) and duodenal erosions (1.1%). Risk factors noticed were chronic smoking (16.8%), alcohol consumption (13.7%), smoking and alcohol use (21.1%), history of peptic ulcer (10.5%) and chronic steroid use (1.1%). CONCLUSION NSAIDs especially aspirin were implicated in maximum number of patients. An increase in occurrence over 5 years, a wide spectrum of disorders and various risk factors were noticed.
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Affiliation(s)
- D Padmini Devi
- Department of Pharmacology, St. John's Medical College, Bangalore, India.
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Simeone M, Tassieri M, Sibillo V, Guido S. Effect of sol–gel transition on shear-induced drop deformation in aqueous mixtures of gellan and κ-carrageenan. J Colloid Interface Sci 2005; 281:488-94. [PMID: 15571707 DOI: 10.1016/j.jcis.2004.08.095] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2004] [Accepted: 08/11/2004] [Indexed: 11/18/2022]
Abstract
In this work, we present an experimental methodology to investigate the dynamics under shear flow of a drop that is gelling as a consequence of a temperature quench. The experiments were carried out on the system water/gellan/kappa-carrageenan in the biphasic region of the phase diagram, the gellan-rich phase being used as the dispersed phase. Gelation was brought about by lowering the temperature during flow after steady state drop deformation had been reached. Simple shear flow was applied by using a parallel plate apparatus equipped with optical microscopy and image analysis, which made it possible to monitor drop shape evolution before, during, and after gelation. The onset of gelation trapped drop deformation, thus producing anisotropic particles. The fingerprint of gelation was the simultaneous tumbling of the drops, which rotated as rigid ellipsoids under the action of shear flow. Interfacial tension between the two equilibrium phases was determined at different times during the temperature quench by analyzing drop retraction upon cessation of flow. Up to gelation, no significant change was observed in the measured values.
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Affiliation(s)
- M Simeone
- Laboratori Giovanni Astarita, Dipartimento di Ingegneria Chimica, Università degli Studi di Napoli Federico II, 80-80125 Naples, Italy.
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Sushma M, Sudha S, Guido S. Pre-electroconvulsive shock administration of calcium channel blockers reduces retrograde amnesia induced by ECS. Indian J Exp Biol 2004; 42:1141-4. [PMID: 15587124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Effect of pre-electroconvulsive shock (ECS) administration of calcium channel blockers (CCBs) like verapamil, diltiazem, nifedipine, nimodipine, flunarizine and cinnarizine on retrograde amnesia induced by ECS was examined using passive avoidance paradigm in rats. The groups (Gr 1-7) of adult, male Wistar rats received true ECS with CCBs (5mg/kg; i.p) or vehicle (10 ml/kg; ip) and other groups (Gr 8-14) received sham ECS with CCBs (5mg/kg; i.p) or vehicle (10 ml/kg; i.p). The anti-amnestic activity of CCBs were evaluated using the passive avoidance paradigm in rats. Results showed that, the baseline latencies for all the groups did not differ significantly. Rats receiving true ECS produced significantly lower latencies. There was increase in the post ECS step through latencies of the rats administered CCBs before ECS. Therefore, pre-ECS administration of calcium channel blockers might reduce retrograde amnesia produced by ECS without altering seizure duration.
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Affiliation(s)
- M Sushma
- Department of Pharmacology, St John's Medical College, Bangalore 560 034, India
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Devi DP, Sushma M, Guido S. Drug induced serious hepatic adverse reactions in a tertiary care centre: a five-year retrospective analysis. Indian J Med Sci 2004; 58:211-2. [PMID: 15166471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Cristini V, Hooper RW, Macosko CW, Simeone M, Guido S. A Numerical and Experimental Investigation of Lamellar Blend Morphologies. Ind Eng Chem Res 2002. [DOI: 10.1021/ie0200961] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Guido S, Simeone M, Alfani A. Interfacial tension of aqueous mixtures of Na-caseinate and Na-alginate by drop deformation in shear flow. Carbohydr Polym 2002. [DOI: 10.1016/s0144-8617(01)00220-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Phenylephrine is a nonselective alpha-receptor agonist. This study examined whether the administration of phenylephrine immediately before electroconvulsive shocks (ECS) attenuated ECS-induced retrograde amnesia. Adult male Wistar rats received phenylephrine (0.25 mg/kg i.p.) or saline 3 min before each of three once-daily true or sham ECS. Retention of pre-ECS learning was studied 1 day after the ECS course using a passive avoidance task. Phenylephrine increased seizure duration in ECS-treated rats, and also enhanced recall in both true and sham ECS groups. The latter finding suggests that phenylephrine nonspecifically improves cognitive functions, perhaps through adrenergic mechanisms that improve memory consolidation and storage. Since phenylephrine increases blood pressure, its cognitive effects also weaken the hypothesis that ECT-induced cognitive impairment results from the seizure-related hypertensive surge.
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Affiliation(s)
- A Anand
- Department of Pharmacology, St. John's Medical College, Bangalore, India
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Abstract
Previous research found that the administration of verapamil and felodipine immediately before electroconvulsive shocks (ECS) attenuated ECS-induced retrograde amnesia. This study examined whether sodium nitroprusside, an antihypertensive drug that does not affect calcium channels, has a similar action. Adult male Sprague-Dawley rats received nitroprusside (0.5 mg/kg ip) or saline 3 minutes before each of three once-daily true or sham ECS. Retention of pre-ECS learning was studied 1 day after ECS using a passive avoidance task. Nitroprusside was associated with increased seizure duration in ECS-treated rats, and with enhanced recall in both true and sham ECS groups. The latter finding suggests that nitroprusside nonspecifically improves cognitive functions, and does not support the hypothesis that ECS-induced cognitive impairment is a result of blood-brain barrier breach. Nitric oxide mechanisms may underlie the benefits purveyed by nitroprusside.
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Affiliation(s)
- S Sudha
- Department of Pharmacology, St. John's Medical College, Bangalore, India
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Guido S, Fohey T. What is the best technique to rebase a complete denture? J Dent Technol 2000; 17:32. [PMID: 11323916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Nalbone C, Guido S. If an economy denture is processed with less expensive teeth and acrylics versus premium acrylics and teeth, what is the cost savings for longevity versus lesser products used, if any? J Dent Technol 2000; 17:30-1. [PMID: 11324072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Abstract
Theoretical predictions for the 3D shape of a Newtonian drop immersed in a Newtonian fluid under slow flow have been available for a long time (C.E. Chaffey and H. Brenner, J. Colloid Interface Sci. 24, 258 (1967); J.M. Rallison, J. Fluid Mech. 98, 625 (1980)). The predictions contain four scalar coefficients, given in terms of the viscosity ratio of the component fluids. In this work, experimental values of such coefficients were measured for the case of two Newtonian fluids in simple shear flow. The experiments were carried out in a parallel plate apparatus, equipped with video-enhanced microscopy, and the measurements were performed by image analysis techniques. The results were also compared to theoretical calculations and provide the first complete assessment of shape predictions for the case of Newtonian fluids. Copyright 1999 Academic Press.
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Affiliation(s)
- S Guido
- Dipartimento di Ingegneria Chimica, Università degli Studi di Napoli "Federico II,", P.le V. Tecchio 80, Naples, 80125, Italy
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Shenoy JB, Guido S. Haematuria caused by oral typhoid vaccine. J Assoc Physicians India 1999; 47:845-6. [PMID: 10778645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Abstract
OBJECTIVE To evaluate the basic safety and feasibility of hospital care at home (Home Hospital (HH)) for treating acutely ill older persons requiring hospitalization. DESIGN Prospective case series SETTINGS AND PARTICIPANTS Community-dwelling persons aged 65 and older requiring acute hospital admission for community-acquired pneumonia, chronic heart failure, chronic obstructive airways disease, or cellulitis. RESULTS Seventeen subjects were treated in HH. One hundred twenty-two could not be enrolled because they presented for admission at times when HH was not operational. Six patients refused to enroll in HH. Subjects treated in HH had comparable clinical outcomes to those treated in the acute hospital and were highly satisfied with HH. Charges for HH care were 60% of those for the acute hospital care. CONCLUSIONS In this pilot study, HH was safe, feasible, highly satisfactory, and cost-effective for certain acutely ill older persons who required acute hospitalization.
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Affiliation(s)
- B Leff
- Johns Hopkins Bayview Medical Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Abstract
The retraction of a deformed drop back to the spherical, equilibrium shape at rest has been the subject of several studies in the literature with the aim of measuring the interfacial tension between the drop and the continuous phase. In this work, the retraction of a drop deformed under the action of a shear flow was analyzed by using the theoretical approach proposed by Rallison in the limit of small deformations. A single exponential decay was then obtained for the time evolution of the deformation parameter in the course of retraction. By fitting such expression to the experimental data the interfacial tension can be determined. Experiments of drop retraction were performed by using a parallel plate apparatus. The experimental trend of the deformation parameter during retraction was well represented by a single exponential decay and the calculated interfacial tension was in good agreement with values reported in the literature for the system investigated. A detailed comparison of the proposed analysis of drop retraction with other methods available in the literature is also presented. Copyright 1999 Academic Press.
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Affiliation(s)
- S Guido
- Dipartimento di Ingegneria chimica, Universitá degli Studi di Napoli "Federico II", P.le V. Tecchio, 80, Naples, 80125, Italy
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Marrucci G, Guido S. Shear Flow Rheology of Liquid Crystalline Polymers. International Journal of Polymer Analysis and Characterization 1995. [DOI: 10.1080/10236669508233874] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
We present here the first quantitative correlation for cell contact guidance in an oriented fibrillar network in terms of biased cell migration. The correlation is between the anisotropic cell diffusion parameter, DA = Dx/Dy, and the collagen gel birefringence, delta n, a measure of axially biased collagen fibril orientation in the x-direction. The cell diffusion coefficients, Dx and Dy, measure the dispersal of cells in the directions coincident with and normal to the axis of fibril orientation, respectively. Three essential methodological components are involved: (i) exploiting the orienting effect of a magnetic field on collagen fibrils during fibrillogenesis to systematically prepare uniform axially oriented collagen gels; (ii) using a microscope/image analysis workstation with precise, computer-controlled rotating and translating stages to automate birefringence measurement and, along with rapid "coarse optical sectioning" via digital image processing, to enable 3-D cell tracking of many cells in multiple samples simultaneously; and (iii) employing a rigorous statistical analysis of the cell tracks to estimate the magnitude and precision of the direction-dependent cell diffusion coefficients, Dx and Dy, that define DA. We find that this measure of biased migration in contact guidance (DA) increases with increasing collagen fibril orientation (delta n) due mainly to a rapid enhancement of migration along the axis of fibril orientation at low levels of fibril orientation, and to a continued suppression of migration normal to the axis of fibril orientation at high levels of fibril orientation.
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Affiliation(s)
- R B Dickinson
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis 55455
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Guido S, Tranquillo RT. A methodology for the systematic and quantitative study of cell contact guidance in oriented collagen gels. Correlation of fibroblast orientation and gel birefringence. J Cell Sci 1993; 105 ( Pt 2):317-31. [PMID: 8408268 DOI: 10.1242/jcs.105.2.317] [Citation(s) in RCA: 159] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite the likely role of contact guidance in every physiological process involving cell migration, its study in a three-dimensional tissue-equivalent environment has been precluded, heretofore, by inherent difficulties in systematically preparing well-defined contact guidance fields and quantifying the resultant contact guidance. Here, we describe a novel use of a magnetic field to orient collagen fibrils during fibrillogenesis, entrapping cells dispersed in the collagen solution. Using computer-controlled staging and image analysis, we show from automated birefringence measurements of the resultant slab of cell-populated gel contained in a specially designed observation chamber that the fibril orientation is biased along the long axis of the chamber uniformly throughout the chamber. Further, we show that the degree of fibril orientation, and consequently the elicited contact guidance, can be controlled by independently varying the magnetic field strength or temperature during fibrillogenesis. We characterize the contact guidance response to the imposed contact guidance field by measuring cell orientation relative to the axis of fibril orientation from still images obtained in time-lapse via automated image analysis. We present the first quantitative correlation of contact guidance (based on cell orientation) with collagen fibril orientation (based on birefringence) for human foreskin fibroblasts cultured in a collagen gel, by using gels of varying orientation resulting from different magnetic field strengths and temperatures during fibrillogenesis, and by using sufficiently low cell concentrations and early observation times.
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Affiliation(s)
- S Guido
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis 55455
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Guido S, Joseph T. Effect of chemically different calcium antagonists on lipid profile in rats fed on a high fat diet. Indian J Exp Biol 1992; 30:292-4. [PMID: 1459596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Different classes of calcium antagonists, viz. verapamil (diphenylalkylamine), diltiazem (benzothiazepine), nifedipine, felodipine and nimodipine (dihydropyridines), were examined for their effects on lipid profile in rats. Clofibrate was the reference standard. Clofibrate significantly prevented the rise of serum triglycerides and total cholesterol produced by high fat diet and raised antiatherogenic index to 1.6 times than that of high fat diet controls. Of the calcium antagonists studied, felodipine was most effective in preventing the rise of serum triglycerides and total cholesterol in high fat diet fed rats. Felodipine's antiatherogenic index was very high (886%)--much more than that of clofibrate (303%). Diltiazem and nimodipine which also significantly prevented the rise in triglycerides and total cholesterol produced by high fat diet had a moderately beneficial antiatherogenic index similar to that of clofibrate. Though verapamil and nifedipine slightly increased the triglyceride levels, total cholesterol levels were reduced only by verapamil and not by nifedipine. Despite this both these drugs moderately raised antiatherogenic index similar to clofibrate.
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Affiliation(s)
- S Guido
- Department of Pharmacology, St. John's Medical College, Bangalore, India
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Guido S. Universal marketing concepts for strategic planning. Manage Focus 1979; 26:12-9. [PMID: 10242694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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