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The article "Angiotensin II induces the exocytosis of galectin-3 via integrin αv/AKT/NF-κB signaling pathway" by L. Tian, D. Coletti, Z.-L. Li, published in Eur Rev Med Pharmacol Sci 2019; 23(13): 5949-5957 has been retracted with the unanimous agreements of all the authors and the Editors-in-Chief, since the corresponding author submitted the manuscript for review without informing and obtaining the agreement of the senior co-authors.
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OBJECTIVE: To explore the role of integrin αv in Angiotensin II (Ang II)-induced exocytosis and endocytosis of galectin-3 (gal-3) in vascular smooth muscle cells (VSMCs). MATERIALS AND METHODS: A primary culture of mouse VSMCs was established by the enzymatic digestion of aorta. Adeno-Cre was used to specifically knockdown integrin αv. VSMCs were treated with Ang II, LY294002 (inhibitor of AKT signaling pathway), and Bay11-7082 (inhibitor of nuclear factor-kappa B, NF-κB), respectively. Endocytosis of His-tagged gal-3 was analyzed by immunofluorescence. The Western blot was performed to detect the protein level in cell supernatant and lysate. RESULTS: Ang II increased the exocytosis of gal-3 and activated AKT and NF-κB signaling pathways. The knockdown integrin αv effectively decreased the activation of AKT and NF-κB signals and the exocytosis of gal-3 induced by Ang II, but it had a little effect on the endocytosis of gal-3. Ang II increased the phosphorylation of AKT and NF-κB through integrin αv. AKT is the upstream signal of the NF-κB signaling pathway. LY294002 or Bay11-7082 could decrease Ang II-induced exocytosis of gal-3 in VSMCs. CONCLUSIONS: Ang II, depending on integrin αv/AKT/NF-κB signaling pathway, induced the exocytosis of gal-3.
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Sunn hemp (Crotalaria juncea L., Fabaceae) is widely used as a cover crop in sugar cane and citrus plantations in Brazil. C. juncea has been reported in São Paulo State (SPS) by Wulff et al. (3) as a host of the phytoplasma associated with symptoms of huanglongbing (HLB) in citrus, a member of group 16SrIX, that induces witches'-broom in sunn hemp (3). In studying the distribution of group 16SrIX phytoplasma in C. juncea in SPS, we identified this species as a new host of two phytoplasmas. Sunn hemp fields were inspected for symptoms usually associated with phytoplasma infections, such as leaf yellowing, shoot proliferation, witches'-brooms, and virescence. Ninety-nine plant samples were collected and DNA was extracted with the CTAB protocol from stems. Nested PCR was carried out with primers P1/P7, followed by amplification with primers fU3/rU5 (2), both sets being universal for phytoplasma. Asymptomatic sunn hemp samples were used as negative controls and were negative in PCR reactions. PCR products were directly sequenced with primers P1/P7 and fU3/rU5 and phytoplasma identification was conducted with BLASTn and in silico RFLP analysis for delineation of subgroups (4). Plants showing leaf yellowing (three plants; Catanduva County), shoot proliferation (one plant; Ibirá County), or witches'-brooms (one plant; Promissão County) symptoms were found to be infected with the 16SrI phytoplasma group, subgroup S. The 16S rDNA sequence (GenBank Accession No. KF878383) showed 99% identity (E value 0.0) with Candidatus Phytoplasma asteris, Onion yellows phytoplasma OY-M (AP006628), Mulberry yellow dwarf phytoplasma (GQ249410), and Ash witches'-broom phytoplasma (AY566302), among other phytoplasmas from the same group. Sunn hemp plants with shoot proliferation (three plants) carried the 16SrXV phytoplasma group, subgroup A, found in Ibirá (two plants) and Catanduva (one plant) counties, SPS. This sequence (GenBank Accession No. KF878382) displayed 99% identity (E value 0.0) with Ca. P. brasiliense, Hibiscus witches'-broom phytoplasma (AF147708), Guazuma ulmifolia witches'-broom phytoplasma (HQ258882, HQ258883), and Cauliflower stunt phytoplasma (JN818845). Both phytoplasma groups described in this report, 16SrI and 16SrXV, were collected in May 2010 and both have limited geographic distribution and occurred at low incidence. Phytoplasma of group 16SrI (Ca. P. asteris) was identified in C. spectabilis in India (1). To our knowledge, this is the first report of phytoplasmas groups 16SrI and 16SrXV in sunn hemp. References: (1) S. Kumar et al. Plant Dis. 94:1265, 2010. (2) E. Seemüller et al. Int. J. Syst. Bacteriol. 44:440, 1994. (3) N. A. Wulff et al. Tropical Plant Pathol. 34:S7, 2009. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.
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Mandibular reconstruction plates have revolutionized the treatment of mandibular continuity defects following ablative or trauma surgery. This retrospective study of patients requiring mandibular reconstruction over a six year period describes the authors' experience with second generation mandibular locking reconstruction plates and identifies complications and risk factors. The use of second-generation locking reconstruction plates for the treatment of mandibular continuity defects has a 36% complication rate, which includes plate fracture, screw loosening, plate exposure, wound infection and malocclusion. The average time frame until a hardware failure (plate fracture, screw loosening) occurs is 14 months. Plate exposure is closely associated with patients who received radiation therapy, and have lateral defects reconstructed with a plate only or plate/soft tissue flap reconstruction. Plate fracture was associated with lateral defects, the presence of a postoperative dentition, and a plate only or plate/soft tissue flap reconstruction. The authors recommend the use of a primary vascularized bone reconstruction. This provides additional soft tissue support around the plate to minimize the chances of exposure. It also provides osseous support for the plate, reducing the time frame the plate endures load bearing, and minimizing the risk of plate fracture.
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Placas Ósseas , Implante de Prótese Mandibular/instrumentação , Prótese Mandibular , Procedimentos Cirúrgicos Ortognáticos/instrumentação , Procedimentos de Cirurgia Plástica/instrumentação , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Humanos , Masculino , Doenças Mandibulares/reabilitação , Doenças Mandibulares/cirurgia , Neoplasias Mandibulares/reabilitação , Neoplasias Mandibulares/cirurgia , Implante de Prótese Mandibular/métodos , Procedimentos Cirúrgicos Ortognáticos/métodos , Desenho de Prótese , Falha de Prótese , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
Necrotizing fasciitis of the cervical facial region is a rare entity that has seen an increasing prevalence in the last 20 years. It is most common in patients with an underlying systemic disease leading to immunosuppression, but can be seen in healthy adults and children. It is characterized by soft tissue destruction which is disproportionate to its clinical symptoms and signs, with rapid progression and fatal outcome, if not treated rapidly and radically. We present a review of the etio-pathogenesis and management of this challenging disease.
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Face , Fasciite Necrosante/patologia , Doenças da Boca/patologia , Pescoço , Infecções dos Tecidos Moles/patologia , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Desbridamento , Fasciite Necrosante/etiologia , Fasciite Necrosante/mortalidade , Fasciite Necrosante/terapia , Humanos , Doenças da Boca/complicações , Infecções dos Tecidos Moles/etiologia , Infecções dos Tecidos Moles/terapia , Adulto JovemRESUMO
This paper reports on the largest series of pathological fractures of the mandible (n=44) in the literature, with the aim of proposing an aetiologic classification and algorithm for treatment. A retrospective review was undertaken of cases treated in the Department of Oral and Maxillofacial Surgery at the University of Maryland Medical Center from 1991 to 2005. Data collected included age, gender, race, aetiology, site, management and outcome. Forty-three patients with 44 pathologic fractures were included. The most common aetiology was osteoradionecrosis (49%), followed by infections (19%) and malignancy (19%). The most frequent primary treatment utilized was mandibular resection of diseased bone and fixation with a locking reconstruction plate alone (55%). Either primary or secondary mandibular reconstruction was performed when co-morbid disease allowed such treatment. Management of pathological fractures is aimed initially at systemic issues, followed by focusing on site-specific issues. This is a complex problem with a 40% complication rate, with radiation therapy associated with 59% of the complications. Free flap reconstruction should be considered when possible, especially in cases secondary to osteoradionecrosis.
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Fraturas Espontâneas/cirurgia , Fraturas Mandibulares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Placas Ósseas , Pré-Escolar , Doença , Feminino , Seguimentos , Fraturas Espontâneas/etiologia , Humanos , Masculino , Mandíbula/cirurgia , Doenças Mandibulares/complicações , Doenças Mandibulares/cirurgia , Fraturas Mandibulares/etiologia , Neoplasias Mandibulares/complicações , Neoplasias Mandibulares/cirurgia , Pessoa de Meia-Idade , Osteomielite/complicações , Osteomielite/cirurgia , Osteorradionecrose/complicações , Osteorradionecrose/cirurgia , Complicações Pós-Operatórias , Procedimentos de Cirurgia Plástica/instrumentação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
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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Envelhecimento/fisiologia , Músculo Esquelético/fisiologia , Doenças Neuromusculares/fisiopatologia , Regeneração , Animais , Diferenciação Celular , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Células-Tronco/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Vasopressinas/metabolismoRESUMO
Polychlorinated biphenyls (PCBs) are structurally related to dioxins, widely used in the past in various industrial applications and daily used products. Although PCBs production was discontinued more than twenty years ago, their chemical stability and high lipophilicity make them persistent pollutants and dangerous occupational contaminants. Skeletal muscle is an important site of PCB accumulation. Our previous results about the effects of PCBs on L6C5 myoblasts, showed that "low concentrations" (< 10 microg/ml) of these compounds inhibit in vitro myogenic differentiation in a concentration-dependent fashion, while toxic effects only begin to be evident at PCB concentrations > or = 10 microg/ml. In the present paper we wondered if the observed cell mortality is due to necrosis or if it depends on the activation of programmed cell death mechanisms (apoptosis). Using different methods of analysis, we have observed that PCBs cause necrosis of myogenic cells and that such effect is related to the employed concentrations and to the time of exposure (EC50 approximately = 50 microg/ml). Our results may help to explain the creatin kinase elevation, observed in the blood of patients acutely exposed to high concentrations of PCBs, as the consequence of a necrotic damage of the skeletal muscle. It will be therefore interesting to evaluate the presence of muscular damages in the chronic exposures to PCBs.
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Poluentes Ambientais/toxicidade , Mioblastos/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Animais , Apoptose , Linhagem Celular , Creatina Quinase/sangue , Citofotometria , Citoplasma/enzimologia , Interpretação Estatística de Dados , Poluentes Ambientais/administração & dosagem , Humanos , L-Lactato Desidrogenase/análise , Mioblastos/patologia , Necrose/induzido quimicamente , Necrose/enzimologia , Bifenilos Policlorados/administração & dosagem , RatosRESUMO
Calcium plays a pivotal role in the establishment of the differentiated phenotype in myogenic cells but the involved molecular mechanisms are still matter of debate. Here we studied the effects of exposing L6-C5 myogenic cells to high extracellular Ca2+ concentration ([Ca2+]o), which induces an increase of intracellular calcium ([Ca2+]i) without involving Ca2+ release from the intracellular stores but exclusively due to plasma membrane influx (Naro et al., 2003). Exposure of L6-C5 cells to [Ca2+]o up to 20 mM for 30 min, before shifting them into a differentiative medium, induced the appearance of multinucleated, myosin-positive myotubes, much larger than in control cells with an increased protein/DNA ratio. These large myotubes showed nuclear accumulation of the hypertrophy marker GATA-2. The hypertrophic growth of these cells was blocked by cyclosporin A (CsA), FK506, or overexpression of a calcineurin-dominant negative protein, suggesting the involvement in this process of the Ca2+ responsive phosphatase calcineurin. Furthermore, transient exposure of L6-C5 cells to high [Ca2+]o increased the expression of luciferase reporter driven by myoglobin (Mb) and beta-MHC promoters but not IIB-MHC and MCK promoters. Luciferase transcription driven by CK promoter was, instead, enhanced by mobilizing Ca2+ from the intracellular stores. These data indicate that a transient increase of [Ca2+]i due to plasma-membrane influx is sufficient to induce a hypertrophic phenotype and an increased expression of slow-fiber genes but not fast-fiber genes.
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Cálcio/metabolismo , Regulação da Expressão Gênica , Fibras Musculares Esqueléticas/citologia , Transcrição Gênica , Animais , Calcineurina/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição GATA2 , Hipertrofia , Desenvolvimento Muscular , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares de Contração Lenta/fisiologia , Miosinas/genética , Miosinas/metabolismo , Regiões Promotoras Genéticas , Ratos , Transdução de Sinais/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Polychlorinated biphenyls (PCBs) are ubiquitous and persistent pollutants whose role in developmental toxicity is of great concern. The observation that the offspring of PCB-exposed mothers (both in humans and rodents) display reduced body mass prompted us to investigate the effects of commercial mixtures of PCB congeners (Aroclor 1232, 1254, and 1262) on differentiation of both a myogenic cell line and primary myogenic cell cultures. The fusion of L6 myoblasts into multinucleated myotubes and the increase of creatine kinase (CK) activity were dose-dependently inhibited by Aroclor 1254 at concentrations (0.1-4 microg/ml) that caused no effect on cell density. Ultrastructural analysis demonstrated that Aroclor 1254 also prevented the accumulation of contractile filaments while inducing hypertrophy of the smooth endoplasmic reticulum and appearance of membrane-filled autophagosomes. Half-maximal inhibition (IC50) of CK activity accumulation occurred at 0.01 microg/ml for Aroclor 1262, 2 microg/ml for Aroclor 1254, and 8 microg/ml for Aroclor 1232. Aroclor-dependent inhibition of myogenic differentiation was also shown by the reduced expression and nuclear accumulation of beta-galactosidase in primary cultures of fetal myoblasts from transgenic mice expressing this reporter gene under the control of the myosin light chain promoter. These data show that skeletal muscle differentiation is specifically impaired by PCBs and may explain the reported depression of body mass growth in PCB-exposed offspring at birth. Furthermore, myogenic cell cultures are highly sensitive to PCBs and allow the detection of biological effects of environmental levels of these pollutants.
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Arocloros/toxicidade , Diferenciação Celular/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Músculo Esquelético/efeitos dos fármacos , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/ultraestrutura , Animais , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/enzimologia , Creatina Quinase/antagonistas & inibidores , Creatina Quinase/metabolismo , DNA/biossíntese , Relação Dose-Resposta a Droga , Retículo Endoplasmático Liso/efeitos dos fármacos , Retículo Endoplasmático Liso/ultraestrutura , Insulina/farmacologia , Camundongos , Camundongos Transgênicos , Músculo Esquelético/citologia , Músculo Esquelético/enzimologia , Fagossomos/efeitos dos fármacos , Fagossomos/ultraestrutura , Ratos , Vasopressinas/farmacologia , beta-Galactosidase/genética , beta-Galactosidase/metabolismoRESUMO
Subcellular targeting of the components of the cAMP-dependent pathway is thought to be essential for intracellular signaling. Here we have identified a novel protein, named myomegalin, that interacts with the cyclic nucleotide phosphodiesterase PDE4D, thereby targeting it to particulate structures. Myomegalin is a large 2,324-amino acid protein mostly composed of alpha-helical and coiled-coil structures, with domains shared with microtubule-associated proteins, and a leucine zipper identical to that found in the Drosophila centrosomin. Transcripts of 7.5-8 kilobases were present in most tissues, whereas a short mRNA of 2.4 kilobases was detected only in rat testis. A third splicing variant was expressed predominantly in rat heart. Antibodies against the deduced sequence recognized particulate myomegalin proteins of 62 kDa in testis and 230-250 kDa in heart and skeletal muscle. Immunocytochemistry and transfection studies demonstrate colocalization of PDE4D and myomegalin in the Golgi/centrosomal area of cultured cells, and in sarcomeric structures of skeletal muscle. Myomegalin expressed in COS-7 cells coimmunoprecipitated with PDE4D3 and sequestered it to particulate structures. These findings indicate that myomegalin is a novel protein that functions as an anchor to localize components of the cAMP-dependent pathway to the Golgi/centrosomal region of the cell.
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3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Centrossomo/metabolismo , Complexo de Golgi/metabolismo , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Drosophila , Imuno-Histoquímica , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Dados de Sequência Molecular , Especificidade de Órgãos , Ligação Proteica , Proteínas/análise , Proteínas/genética , Ratos , Saccharomyces cerevisiae , Análise de SequênciaRESUMO
BACKGROUND: A combination of an antipsychotic medication and a mood stabilizer is often used for initial treatment of acute psychotic mania. However, the optimal duration of this adjunctive antipsychotic medication is unknown. METHOD: As part of a lithium efficacy study, acutely manic adolescents with psychotic features were given open combination treatment with lithium and an adjunctive antipsychotic medication. If the psychosis resolved, the antipsychotic medication dose was gradually tapered and discontinued after 4 weeks of therapeutic lithium levels. The subject was then given a trial of maintenance lithium monotherapy for up to 4 weeks. RESULTS: Significant improvement was seen in 64% of the sample with psychotic features after 4 weeks of combination treatment. However, few maintained their response after discontinuation of the antipsychotic medication. Successful discontinuation of antipsychotic medication in this sample was associated with first episode, shorter duration of psychosis, and the presence of thought disorder at baseline. CONCLUSIONS: Adjunctive antipsychotic medication needs to be maintained for longer than 4 weeks in the vast majority of adolescents with psychotic mania, even though the manic and psychotic symptoms have resolved and lithium treatment is maintained. Future studies to determine the optimal duration of adjunctive antipsychotic medication treatment are warranted.
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Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Lítio/uso terapêutico , Lorazepam/uso terapêutico , Adolescente , Transtorno Bipolar/diagnóstico , Criança , Quimioterapia Combinada , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Risperidona/uso terapêutico , Índice de Gravidade de DoençaRESUMO
Adolescents with acute psychotic mania were treated with lithium and adjunctive haloperidol as part of a lithium efficacy study. If the psychosis completely resolved, haloperidol was discontinued after 1 week of therapeutic lithium levels. Our first five subjects experienced a rapid exacerbation of symptoms, which responded to restarting haloperidol. A longer duration of adjunctive antipsychotic treatment is necessary in adolescents with bipolar psychosis.
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Transtorno Bipolar/complicações , Transtorno Bipolar/tratamento farmacológico , Quimioterapia Combinada , Haloperidol/uso terapêutico , Lítio/uso terapêutico , Transtornos Psicóticos/complicações , Transtornos Psicóticos/tratamento farmacológico , Doença Aguda , Adolescente , Fatores Etários , Criança , Método Duplo-Cego , Feminino , Haloperidol/administração & dosagem , Humanos , Lítio/administração & dosagem , Masculino , Testes Psicológicos , Índice de Gravidade de Doença , Fatores de TempoRESUMO
In order to isolate, characterize, and establish culture cell lines with different diagnostic and prognostic significance, derived from multiclonal neoplasms, a ductal infiltrating mammary tumor was induced in rats by 7,12-dimethylbenz[a]anthracene. Clones with different DNA/protein content, being the DI of 1.16, 1.30, and 1.60, respectively, were observed in the primary tumor. Biparametric flow cytometry suggested that the clone at 1.30 is made up of two subpopulations with different protein and slightly different DNA contents. The culture, after a few passages, exhibited the presence of aneuploid cells and the absence of diploid components, demonstrating that only tumor cells survived. The limiting dilution method gave rise to four lines with DI of 1.16, 1.25, 1.30, and 1.50; a mean chromosome number of 45, 46, 47, and 88, respectively; and different morphological and ultrastructural features. These characteristics were stable during the experimental procedure, that is, for about 20 passages. Conversely, the detection of cytoskeletal proteins indicated that the tumor epithelial cells underwent early dedifferentiation into sarcoma-like cells showing markers of stromal cell type and thus exhibiting phenotypic instability in vitro, a feature reported in many advanced human breast cancers in vivo. In conclusion, this cellular model represents the in vivo situation and appears suitable for in vitro studies of tumor cell characteristics and might be used to predict clinical behavior.
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Técnicas de Cultura de Células , Neoplasias Mamárias Experimentais , Células Tumorais Cultivadas , Animais , Técnicas de Cultura de Células/métodos , Citoesqueleto/metabolismo , DNA de Neoplasias/análise , Feminino , Citometria de Fluxo/métodos , Imuno-Histoquímica/métodos , Neoplasias Mamárias Experimentais/induzido quimicamente , Microscopia Eletrônica/métodos , Proteínas de Neoplasias/análise , Ratos , Ratos Sprague-DawleyRESUMO
Phospholipase D (PLD) activation involved in signal transduction may lead to the hydrolysis of conspicuous amounts of phosphatidylcholine (PC). This study shows that PLD activation significantly alters the plasma membrane (PM) environment and the membrane exchange dynamics. PC-PLD activation in vasopressin (AVP)-stimulated L6 myogenic cells was accompanied by increased exocytosis and decreased membrane fluidity, as shown by transmission EM and fluorescence spectroscopy of trimethylammonium-diphenyl-hexatriene. AVP-induced exocytosis appeared to be brefeldin A-insensitive. PLD inhibition by Zn(2+) and PC de novo synthesis inhibition by hexadecylphosphocholine abolished AVP-induced vesicle traffic. Upon AVP stimulation, metabolically labeled PC decreased in PM, then transiently increased in microsomes, and returned to the prestimulus level in the PM within 5 min, a phenomenon requiring PC neosynthesis and microtubule functionality. Vesicle traffic with similar features was also observed after endothelin-1-induced PC-PLD activation in rat peritubular myoid cells. These results indicate that, in nonsecretory cells, exocytosis coupled to PC de novo synthesis restores PM-PC, conspicuously consumed during PLD-mediated signal transduction.
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Arginina Vasopressina/farmacologia , Membrana Celular/fisiologia , Fosfatidilcolinas/metabolismo , Fosfolipase D/metabolismo , Acrilamida/farmacologia , Androstadienos/farmacologia , Animais , Brefeldina A/farmacologia , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Citocalasina B/farmacologia , Difenilexatrieno/análogos & derivados , Ativação Enzimática , Exocitose , Corantes Fluorescentes , Cinética , Lipídeos de Membrana/metabolismo , Músculo Esquelético , Nocodazol/farmacologia , Paclitaxel/farmacologia , Ratos , Wortmanina , Zinco/farmacologiaRESUMO
The plasma membrane is dynamically remodeled as a function of the cell cycle, motility and membrane traffic. We have previously shown that arg8-vasopressin (AVP) stimulation of L6 myoblasts induces the activation of phosholipase D during the first minutes of stimulation, and the differentiation of 1,6 myoblasts as a long term effect. We now report that AVP also induces two types of morphological responses in L6 cells within a few minutes of stimulation: exocytosis, apparent as uncoated pits, and the generation of membrane projections and reffles. Thus, such an experimental model is suitable for the study of hormone-induced morphological surface modifications and their regulatory mechanisms. In L6 cells, AVP-induced projection generation depends on the integrity of microfilaments, intermediate filaments, and microtubules. Moreover, projection generation and exocytosis appear to be independently regulated phenomena: in fact, inhibition of the de novo synthesis of phosphatidylcholine inhibits membrane traffic but fails to block projection appearance. Conversely, the latter phenomenon, unlike exocytosis, is mediated by PI3-kinase signaling. Thus, AVP induces two early, independently regulated morphological modifications in L6 cells: exocytosis, involved in plasma membrane phospholipid turnover, and membrane projections, likely involved in cell migration.
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Membrana Celular/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Vasopressinas/farmacologia , Laranja de Acridina/farmacologia , Acrilamida/farmacologia , Androstadienos/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular , Membrana Celular/ultraestrutura , Movimento Celular , Citocalasina B/farmacologia , Inibidores Enzimáticos/farmacologia , Exocitose/efeitos dos fármacos , Corantes Fluorescentes/farmacologia , Fluorometria , Cinética , Ligantes , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Músculos/citologia , Músculos/ultraestrutura , Paclitaxel/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipídeos/metabolismo , Fosforilcolina/farmacologia , Ratos , Transdução de Sinais , Fatores de Tempo , WortmaninaRESUMO
OBJECTIVES: In vivo wear of composite restorative materials appears to be, in part, dependent on various patient factors. Specifically, consumption of alcoholic beverages has the potential for increasing the degradation rate. The hypothesis tested in this experiment was that composite wear is dependent on the type of alcohol-containing liquid the materials are exposed to during three-body abrasive wear. METHODS: To test this hypothesis, composite wear experiments were performed using the ACTA three-body wear machine. Abrasive slurries containing either beer, wine, 9 vol% ethanol or water were used during the wear experiments. The data were analyzed using ANOVA and Tukey's test. RESULTS: The wine and ethanol solutions caused significantly more wear compared to the beer and water. There was no significant differences in the wear between the wine and 9 vol% ethanol groups, and the beer groups were not significantly different from the water groups. Furthermore, there was no significant interaction between the composite type and the various abrasive slurries. SIGNIFICANCE: These results indicate that alcoholic beverages with at least 9 vol% ethanol will increase the wear of composite. The observed increase in wear of composite by the wine was caused primarily by the ethanol content of the wine. Other constituents in the wine do not appear to have an effect on composite wear. The ethanol effect was consistent among different composite types.
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Bebidas Alcoólicas , Resinas Compostas/química , Desgaste de Restauração Dentária , Análise de Variância , Cerveja , Bis-Fenol A-Glicidil Metacrilato/química , Etanol/química , Teste de Materiais , Cimentos de Resina/química , Dióxido de Silício/química , Estatísticas não Paramétricas , Vinho , Zircônio/químicaAssuntos
Arginina Vasopressina/farmacologia , Fosfatidilcolinas/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Transporte Biológico/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Colina/metabolismo , Células L , Camundongos , Organelas/metabolismo , Organelas/ultraestruturaRESUMO
OBJECTIVE: To examine if childhood psychiatric diagnoses are associated with family history, psychosis, age, and lithium response. METHOD: Associations among variables, and their contributions to explaining lithium response were examined in 48 bipolar adolescents enrolled in a study of lithium. RESULTS: Presence of a childhood diagnosis was not associated with family psychiatric history or lithium response. Subjects with psychotic features, however, were less likely to have a childhood psychiatric diagnosis, were older, and had a poorer response rate to lithium than subjects without psychosis. DISCUSSION: Heterogeneity within bipolar adolescents may be based on clinical features such as psychosis rather than childhood or family history alone.
Assuntos
Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Carbonato de Lítio/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Adolescente , Antimaníacos/efeitos adversos , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/genética , Criança , Comorbidade , Método Duplo-Cego , Feminino , Predisposição Genética para Doença/genética , Humanos , Carbonato de Lítio/efeitos adversos , Masculino , Prognóstico , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/genética , Fatores de Risco , Resultado do TratamentoRESUMO
Thirteen patients with accelerated phase of chronic myeloid leukemia (CML-AC) were treated with intravenous plicamycin and subcutaneous alpha-interferon. Two patients stabilized, three patients had partial hematologic responses and one patient had a hematologic complete response with a major cytogenetic response. Two patients, progressing on hydroxyurea, did not respond, but demonstrated re-sensitization to hydroxyurea after completion of induction therapy and had prolonged return to chronic phase for 30 months and 25 months. Four non-responders subsequently received additional chemotherapy and responded. Median survival of all study patients from the development of accelerated phase of CML was 24 months: substantially longer than other reported series (median 6 months). Plicamycin appears to add efficacy to interferon in the stabilization of accelerated phase of CML.