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1.
Nurs Educ Perspect ; 42(6): E168-E170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32649476

RESUMO

ABSTRACT: Puzzle rooms, recently termed "escape rooms," have been in existence for several years and are increasing in popularity in the United States. These experiential learning rooms create an inviting learning environment for both the academic and acute care learner. Learners are placed in strategic cooperative learning groups to promote teamwork, collaboration, critical thinking, and communication. Participation in an escape room can be used to reinforce policies and procedures that are standard in nursing practice. Overall acceptance of this novel idea in nursing was positive for registered nurse, student, and community member outcomes; evaluations were affirmative for learning engagement.


Assuntos
Aprendizagem Baseada em Problemas , Estudantes de Enfermagem , Comunicação , Humanos , Aprendizagem , Políticas , Pensamento , Estados Unidos
2.
ACS Nano ; 14(11): 14846-14860, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33170644

RESUMO

Sequential infiltration synthesis (SIS) is a route to the precision deposition of inorganic solids in analogy to atomic layer deposition but occurs within (vs upon) a soft material template. SIS has enabled exquisite nanoscale morphological complexity in various oxides through selective nucleation in block copolymers templates. However, the earliest stages of SIS growth remain unresolved, including the atomic structure of nuclei and the evolution of local coordination environments, before and after polymer template removal. We employed In K-edge extended X-ray absorption fine structure and atomic pair distribution function analysis of high-energy X-ray scattering to unravel (1) the structural evolution of InOxHy clusters inside a poly(methyl methacrylate) (PMMA) host matrix and (2) the formation of porous In2O3 solids (obtained after annealing) as a function of SIS cycle number. Early SIS cycles result in InOxHy cluster growth with high aspect ratio, followed by the formation of a three-dimensional network with additional SIS cycles. That the atomic structures of the InOxHy clusters can be modeled as multinuclear clusters with bonding patterns related to those in In2O3 and In(OH)3 crystal structures suggests that SIS may be an efficient route to 3D arrays of discrete-atom-number clusters. Annealing the mixed inorganic/polymer films in air removes the PMMA template and consolidates the as-grown clusters into cubic In2O3 nanocrystals with structural details that also depend on SIS cycle number.

3.
J Chem Phys ; 151(19): 190901, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31757164

RESUMO

Sequential infiltration synthesis (SIS) is an emerging materials growth method by which inorganic metal oxides are nucleated and grown within the free volume of polymers in association with chemical functional groups in the polymer. SIS enables the growth of novel polymer-inorganic hybrid materials, porous inorganic materials, and spatially templated nanoscale devices of relevance to a host of technological applications. Although SIS borrows from the precursors and equipment of atomic layer deposition (ALD), the chemistry and physics of SIS differ in important ways. These differences arise from the permeable three-dimensional distribution of functional groups in polymers in SIS, which contrast to the typically impermeable two-dimensional distribution of active sites on solid surfaces in ALD. In SIS, metal-organic vapor-phase precursors dissolve and diffuse into polymers and interact with these functional groups through reversible complex formation and/or irreversible chemical reactions. In this perspective, we describe the thermodynamics and kinetics of SIS and attempt to disentangle the tightly coupled physical and chemical processes that underlie this method. We discuss the various experimental, computational, and theoretical efforts that provide insight into SIS mechanisms and identify approaches that may fill out current gaps in knowledge and expand the utilization of SIS.

4.
Nanoscale ; 10(44): 20505-20513, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30397691

RESUMO

In many applications, interfaces govern the performance of membranes. Structure, chemistry, electrostatics, and other properties of interfaces can dominate the selectivity, flux, fouling resistance, and other critical aspects of membrane functionality. Control over membrane interfacial properties, therefore, is a powerful means of tailoring performance. In this Minireview, we discuss the application of atomic layer deposition (ALD) and related techniques in the design of novel membrane interfaces. We discuss recent literature in which ALD is used to (1) modify the surface chemistry and interfacial properties of membranes, (2) tailor the pore sizes and separation characteristics of membranes, and (3) enable novel advanced functional membranes.

5.
ACS Nano ; 12(8): 8678-8685, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30107114

RESUMO

Crude oil fouling on membrane surfaces is a persistent, crippling challenge in oil spill remediation and oilfield wastewater treatment. In this research, we present how a nanosized oxide coating can profoundly affect the anti-crude-oil property of membrane materials. Select oxide coatings with a thickness of ∼10 nm are deposited conformally on common polymer membrane surfaces by atomic layer deposition to significantly mitigate fouling during filtration processes. TiO2- and SnO2-coated membranes exhibited far greater anti-crude-oil performance than ZnO- and Al2O3-coated ones. Tightly bound hydration layers play a crucial role in protecting the surface from crude oil adhesion, as revealed by molecular dynamics simulations. This work provides a facile strategy to fabricate crude-oil-resistant membranes with negligible impact on membrane structure, and also demonstrates that, contrary to common belief, excellent crude oil resistance can be achieved easily without implementation of sophisticated, hierarchical structures.

6.
Biomed Environ Sci ; 11(3): 203-17, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9861479

RESUMO

The necessity for understanding normal human cognitive processes and behavior, and the mechanisms which result in dysfunction in these processes are dependent on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of humans. The choice of rats in cognition research studies has specific advantages in that these animals possess similar pharmacodynamic parameters to humans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the performance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of food also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous system responsiveness of rat strains to chemical and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessment of neurobehavioral functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models.


Assuntos
Sistema Nervoso Central/fisiologia , Cognição , Dieta , Memória , Ratos Endogâmicos , Animais , Modelos Animais de Doenças , Humanos , Ratos , Reprodutibilidade dos Testes , Estações do Ano
8.
Toxicol Pathol ; 23(6): 701-14; discussion 714-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8772256

RESUMO

The beneficial effects derived from the use of chemicals in agriculture, energy production, transportation, pharmaceuticals, and other products that improve the quality of life are clearly established. However, continued exposure to these chemicals is only advantageous in conditions where the benefit far outweighs toxic manifestations. By law, determination of risk of toxicity necessitates the use of laboratory animals to establish whether chemical exposure is safe for humans. To simulate the human condition, it is incumbent upon investigators to choose a species in which pharmacokinetic and toxicokinetic principles are established and resemble those of humans. Some of the advantages to the use of rat in chemical toxicity testing include (a) similarities in metabolism, anatomy, and physiological parameters to humans; (b) the short life span, especially for carcinogenesis study; (c) the availability, ease of breeding, and maintenance at a relatively low cost; and (d) the existence of a large database to enable comparison of present to reported literature findings. However, the choice of rat can be complicated by several factors such as sex, age, and nutrition, but especially strain, where currently there are over 200 different strains of rat known to exist. The aim of this review is to demonstrate that there are differences in the responsiveness of rat strains to chemicals and that the susceptibility observed is dependent on the tissue examined. It is evident that the genotype differs among strains, and this may be responsible for differences in sensitivities to chemicals. Awareness of strain as a factor in susceptibility to toxicant action needs to be taken into account in interpretation of relevance of risk of toxicity for humans.


Assuntos
Ratos Endogâmicos , Especificidade da Espécie , Testes de Toxicidade , Animais , Ratos
10.
Toxicol Pathol ; 21(1): 1-14, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8378702

RESUMO

This study was intended to identify changes caused by short-term reduced feed intake in rats such as may occur with unpalatable feed or other forms of anorexia. For 2 wk, groups of rats (10/sex/group) were fed ad libitum (control group) or given 75% (mildly restricted group), 50% (moderately restricted group), or 25% (severely restricted group) of the amount of feed eaten the day before by controls. The control group and mildly restricted group grew steadily, but the terminal body weights of the mildly restricted group (both males and females) were only about 80% of controls. The moderately restricted group did not grow during the first week but grew slightly during the second week (terminal body weights about 65% of control). The severely restricted group lost weight throughout the study (terminal weight about 40% of control). Restricted groups exhibited hemoconcentration directly related to the degree of feed restriction. White blood cell counts were reduced (principally due to lymphopenia) in severely restricted rats. Platelet counts were decreased in all restricted groups. Total serum protein concentration was reduced (decreased globulins) in all female restricted groups and in the severely restricted males. The severely restricted rats had increased serum bilirubin, electrolyte derangements, and (in females only) decreased cholesterol. Thymus and liver weights (absolute and relative) were decreased in the moderately and severely restricted groups. All the feed-restricted groups had an increased incidence of superficial gastric erosions. The mildly and moderately restricted groups had slightly decreased hematopoietic tissue in sternal bone marrow, while the severely restricted group had bone marrow necrosis, thymic atrophy, and mild testicular degeneration. Findings in the severely restricted group were distinct from those in the other groups on the basis of their severity and were considered adverse. Changes in the mildly and moderately restricted groups were considered adaptive and innocuous since feed restriction of this degree has historically been associated with increased longevity and decreased disease incidence in chronic studies.


Assuntos
Privação de Alimentos/fisiologia , Toxicologia/métodos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Atrofia , Peso Corporal/fisiologia , Relação Dose-Resposta a Droga , Contagem de Eritrócitos , Feminino , Hematócrito , Hemoglobinas/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Timo/patologia
11.
Lab Invest ; 64(4): 574-84, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2016860

RESUMO

In the investigation of cellular changes associated with intracellular drug storage, we incubated cultured rabbit aorta muscle cells with various amphiphilic agents. Disobutamide, chloroquine, and desipramine each increased cellular content of rhamnose, arabinose, mannose, glucose, and total saccharides; these agents also elevated total and individual phospholipid of all classes. Amiodarone did not alter total saccharide content, but increased total phospholipid. Tilorone, in contrast, decreased total saccharides, but phospholipid content was unchanged. All test agents decreased xylose content. By light microscopy, disobutamide, chloroquine, and tilorone induced clear cytoplasmic vacuoles; desipramine induced dense cytoplasmic granules; and amiodarone induced both cytoplasmic changes. By electron microscopy, the content of the cellular alterations induced by disobutamide was primarily electron lucent; that of the alterations induced by desipramine was primarily concentric lamellar bodies/flocculent electron-dense structures; and that of the alterations induced by amiodarone was a mixture of both. There was no correlation, therefore, between the induced cellular chemical contents and morphologic changes. Despite the physicochemical similarity of the amphiphilic drugs (all have cationic and lipophilic moieties), the chemical responses they induced were different. The results suggest that amphiphilic drugs alter processes involving saccharides as well as those of phospholipid metabolism. The origin of the saccharide moieties associated with the induced changes in monosaccharide contents is not known. Increased content of phosphatidylinositol, mannose, and glycosyl residues is consistent with the suggestion that amphiphilic drugs may cause an increase in membrane anchor synthesis. The inhibition of lysosomal enzyme activities responsible for the degradation of phospholipid and other anchors may also account for the observed increase in monosaccharides and phosphatidylinositol content.


Assuntos
Aminas/farmacologia , Aorta/citologia , Monossacarídeos/metabolismo , Músculo Liso Vascular/citologia , Fosfolipídeos/metabolismo , Amiodarona/farmacologia , Animais , Antiarrítmicos/farmacologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/ultraestrutura , Células Cultivadas , Cloroquina/farmacologia , Desipramina/farmacologia , Etilenodiaminas/farmacologia , Cinética , Microscopia Eletrônica , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/ultraestrutura , Piperidinas/farmacologia , Coelhos , Tilorona/farmacologia
12.
Lab Anim Sci ; 40(6): 625-8, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2172628

RESUMO

Three Mycoplasma spp. were isolated from five colony bred laboratory dogs (Canis familiaris) obtained from a single vendor. Four of these animals were Beagles and one was a mongrel. Three displayed clinical signs of respiratory disease including dyspnea, chronic coughing and moist rales, while the other two dogs were observed during thoracic surgery to have macroscopic lesions suggestive of pneumonia. All five dogs were submitted for diagnostic necropsy during which they were cultured for bacteria and mycoplasma. Mycoplasma spp. having three distinct colonial forms were isolated from the lungs of each of the animals. These three isolates were sent to the National Cancer Institute Diagnostic Microbiology Laboratory and to the National Institutes of Health, NIAID, Mycoplasmology Laboratory. Neither laboratory could serotype these isolates against antisera to 73 Mycoplasma spp., including the common canine mycoplasmas, and nine Acholeplasma spp. Histologically, the bronchopneumonia was characterized by bronchiectasis, purulent bronchiolitis, bronchial and bronchiolar epithelial hyperplasia, chronic non-suppurative peribronchiolitis and perivasculitis, bronchiolitis obliterans, and acute to subacute purulent pneumonia. The similarity between the pathologic findings in these animals and those observed in respiratory mycoplasmosis of other species, e.g. the rat, suggests a causal relationship between the isolated mycoplasmas and the pulmonary disease observed in these dogs.


Assuntos
Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Pneumonia por Mycoplasma/veterinária , Animais , Técnicas de Tipagem Bacteriana , Cães , Feminino , Masculino , Mycoplasma/classificação , Mycoplasma/crescimento & desenvolvimento , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Pneumonia por Mycoplasma/microbiologia , Pneumonia por Mycoplasma/patologia , Especificidade da Espécie
13.
In Vitro Cell Dev Biol ; 26(1): 61-6, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2307639

RESUMO

This study was conducted to identify a defined, serum-free culture medium that supports cell dependent contraction of a collagen lattice. Collagen lattices were found to contract in cultures containing human foreskin fibroblasts (HFF) or rabbit aortic smooth muscle (RASM) cells incubated in serum-free medium. HFF and RASM cells required different supplements to contract the collagen gels. HFF cultured in Dulbecco's modified Eagle's (DME) medium supplemented with bovine serum albumin (BSA) and either endothelial cell growth supplement (EnGS), insulin (In), or platelet derived growth factor (PDGF) supported collagen lattice contraction. Replacement of BSA with casein without the addition of other supplements improved contraction. In contrast, RASM cells supplemented with BSA, EnGS, In, and PDGF were able to contract collagen gels only minimally. Similar to HFF, RASM cells cultured in DME medium supplemented with casein, but without the addition of other supplements, contracted collagen lattices. HFF-mediated collagen contraction was inhibited by prostaglandins E1 or E2, fibronectin, or ascorbic acid. The reported serum-free model provides a useful in vitro method to investigate the role of serum and nonserum factors regulating cell mediated-contraction of insoluble collagen fibrils.


Assuntos
Colágeno/ultraestrutura , Fibroblastos/fisiologia , Músculo Liso Vascular/fisiologia , Animais , Ácido Ascórbico/farmacologia , Células Cultivadas , Meios de Cultura , Ditiotreitol/farmacologia , Fibronectinas/farmacologia , Substâncias de Crescimento/farmacologia , Hormônios/farmacologia , Humanos , Técnicas In Vitro , Masculino , Prostaglandinas E/farmacologia , Coelhos
14.
Toxicol In Vitro ; 4(4-5): 497-505, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-20702220

RESUMO

Cultured cells were found to be highly useful for investigating intracellular storage of amphiphilic compounds using disobutamide as a model agent. To select types of cultured cells most suitable for investigations, cells of dog coronary artery muscle, rabbit aorta muscle, rat urinary bladder carcinoma, rat basophilic leukaemia, human skin fibroblasts, bovine aorta endothelium, Chinese hamster ovary tumour and mouse fibroblasts were incubated with 0, 1, 2, 4, 6, 8 and 10 x 10(-4)m-disobutamide for 24 hr. Cultures were examined in situ by phase light microscopy for the presence of clear cytoplasmic vacuoles, cell death (cell detachment), and for drug effect on confluency/cell count. Disobutamide induced vacuoles in all cell types except rat leukaemia. The drug induced cell death and reduction in confluency or cell count in cultures of all cell types except rat carcinoma and rabbit aorta muscle. Release of lactic dehydrogenase from cells confirmed the relative resistance of the rat carcinoma and rabbit cells, and susceptibility of rat leukaemia, to drug-induced cell death. By means of electron microscopy of rat carcinoma and rabbit cells, it was established that vacuoles were membrane-bound and their content was predominantly electron-lucent.

15.
Toxicol Appl Pharmacol ; 101(1): 70-82, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2799819

RESUMO

In the investigation of the dynamic nature of intracellular drug-induced storage disorder associated with clear cytoplasmic vacuoles (CCV), rat urinary bladder carcinoma cells (RBT CC-8) were cultured with [14C]disobutamide. Cell monolayers were then harvested and analytical cell fractionation techniques were employed to examine the association of disobutamide with the various subcellular fractions. Disobutamide distributed into two modes: as a free, organelle-independent fraction and as a light membrane-associated fraction that overlapped with markers for the plasma membrane, endoplasmic reticulum, and lysosomes. The similarity in buoyant densities of these organelles derived from RBT CC-8 cells precluded resolution of these structures by isopycnic centrifugation. In additional experiments, disobutamide was incubated in vitro with a suspension of isolated rabbit renal proximal tubules. In these cells, analytic fractionation showed that the drug localized predominantly to lysosomes and to a separate light membrane fraction that was clearly resolved from the markers for the endoplasmic reticulum, brush border, mitochondria, and peroxisomes; this fraction overlapped with the most buoyant aspects of the Golgi apparatus and basolateral plasma membrane. The buoyant density of this disobutamide-associated nonlysosomal fraction was 1.11 g/ml. Electron microscopy of the disobutamide-exposed tubules showed a substantial formation of apical vesicles, especially small, smooth-surfaced vesicles, typical of the endocytic apparatus. From these findings and based on the physicochemical properties of the cationic moiety of disobutamide, we conclude that the drug localizes in lysosomal and nonlysosomal acidic vesicles.


Assuntos
Cátions/farmacocinética , Lisossomos/metabolismo , Piperidinas/farmacocinética , Frações Subcelulares/metabolismo , Vacúolos/metabolismo , Animais , Cátions/toxicidade , Fracionamento Celular/métodos , Túbulos Renais Proximais/metabolismo , Piperidinas/toxicidade , Coelhos , Ratos , Células Tumorais Cultivadas , Vacúolos/efeitos dos fármacos
16.
Toxicol Appl Pharmacol ; 97(1): 57-71, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2464862

RESUMO

Disobutamide, a bis tertiary amine (pKa1 = 8.6; pKa2 = 10.2) cationic amphiphilic compound, and a putative cardiac antiarrhythmic drug induced clear cytoplasmic vacuoles in dogs and rats. Ultrastructurally, the vacuoles were membrane-bound vesicles containing primarily electron-lucent material. Some concentric lamellar bodies indicative of phospholipidosis were also present. Although numerous vacuoles were seen in one-year toxicity studies in dogs and rats, there was no apparent evidence of necrosis, inflammation, atrophy, hypoplasia, hyperplasia, or metaplasia. Clinical signs or laboratory findings indicative of functional impairment were also not apparent. The picture of the vacuolation in vivo was one of storage. In cultured cells vacuoles were shown to be storage sites for disobutamide and specifically in distended vesicles of the cytoplasmic acidic compartments, such as lysosomes, endocytic, and probably transport vesicles. Storage of the drug in acidic vesicles is compatible with the dibasic nature of the cationic moiety of disobutamide. The intrinsic cell chemicals which accumulate in the vacuoles along with disobutamide remain unknown. Disobutamide may be a useful agent for defining experimentally the borderline between physiologic limits (normal function) and toxicity (functional impairment) in the condition of intracellular drug storage abnormalities and for advancing knowledge of storage mechanisms.


Assuntos
Antiarrítmicos/toxicidade , Piperidinas/toxicidade , Animais , Antiarrítmicos/metabolismo , Células Cultivadas , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/ultraestrutura , Meios de Cultura , Citoplasma/efeitos dos fármacos , Citoplasma/ultraestrutura , Cães , Avaliação Pré-Clínica de Medicamentos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/ultraestrutura , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/ultraestrutura , Rim/efeitos dos fármacos , Rim/ultraestrutura , Microscopia Eletrônica/métodos , Músculo Liso/efeitos dos fármacos , Piperidinas/metabolismo , Ratos , Coloração e Rotulagem , Relação Estrutura-Atividade , Úvea/efeitos dos fármacos , Úvea/ultraestrutura , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
17.
Toxicol Pathol ; 17(1 Pt 2): 145-52, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2749138

RESUMO

Disseminated panarteritis was found in 16 (9 males and 7 females) of 49 laboratory beagle dogs (25 males and 24 females) from one breeding kennel. The dogs had been used in a 6-month oral toxicity study. Panarteritis was not associated with clinical or gross abnormalities. The incidence was similar in the control and test article-treated groups. Mainly medium-sized arteries throughout the body, particularly intercostal arteries (at their aortic origin), and coronary, epididymal and thymic vessels were affected. Chronic mononuclear-cell periarteritis was the predominant feature. Mixed cellular inflammation of the wall, proliferation or degeneration of muscle cells, focal "fibrinoid" material in the tunica media, fragmented internal elastic lamina and intimal thickening associated with myointimal cellular proliferation also occurred. These histologic changes are compatible with those of immune arteritis. Round worm intestinal infestation and granulomas of visceral larva migrans were common in several organs. Statistical analyses suggested that the pedigree of dogs is related to panarteritis, but the presence or absence of parasitization alone is not. The possible roles of genetic predilection and/or parasites in the pathogenesis are discussed. This panarteritis is spontaneous and may complicate the interpretation of lesions in toxicity studies.


Assuntos
Arterite/fisiopatologia , Doenças do Cão/fisiopatologia , Animais , Arterite/genética , Arterite/veterinária , Doença das Coronárias/patologia , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Epididimo/patologia , Epididimo/fisiopatologia , Feminino , Larva Migrans/parasitologia , Larva Migrans/fisiopatologia , Masculino , Testículo/patologia
20.
Proc Soc Exp Biol Med ; 184(2): 165-71, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3809171

RESUMO

Disobutamide (D), an antiarrhythmic cationic amphiphilic amine (CAA), was withdrawn from clinical testing when clear cytoplasmic vacuoles (CCV) were found in the rat and dog during toxicity studies. To delineate the structural determinants of amines that induce CCV, we exposed cultured rat urinary bladder carcinoma and rabbit aorta muscle cells to numerous cationic drugs and chemicals and examined cells by phase light microscopy. The cationic moiety of these CAA was responsible for the induction of CCV. The very potent inducers were compounds that had two strongly basic amine (cationic) centers. The bis tertiary amines were particularly potent inducers. Aliphatic diamines of minimal lipophilicity-induced CCV, thus showing that an "amphiphilic" structural feature, though present in many CAA drugs, is not necessary for CCV induction. The distance between the two cationic centers was irrelevant to the induction of CCV. These results support the concept that CCV are a manifestation of intracellular (e.g., intralysosomal) drug storage. These structural delineations will be useful in future drug design and for further understanding of drug-cell interactions. Based on these findings, we were able to synthesize an antiarrhythmic CAA which did not induce CCV.


Assuntos
Aminas/farmacologia , Diaminas/farmacologia , Organoides/ultraestrutura , Tensoativos/farmacologia , Vacúolos/ultraestrutura , Animais , Aorta/efeitos dos fármacos , Aorta/ultraestrutura , Linhagem Celular , Células Cultivadas , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/ultraestrutura , Piperidinas/farmacologia , Coelhos , Ratos , Relação Estrutura-Atividade , Neoplasias da Bexiga Urinária/ultraestrutura , Vacúolos/efeitos dos fármacos
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