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1.
Food Chem ; 156: 117-22, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24629946

RESUMO

The influence of droplet size (d32=0.21, 0.70 or 2.2µm) and oil digestibility (corn oil versus mineral oil) on the bioavailability of a model long chain fatty acid (heptadecanoic acid) and lipophilic nutraceutical (Coenzyme Q10) was investigated using a rat feeding study. Initially, we showed that small droplets were digested more rapidly than large droplets using a simulated small intestinal model (pH stat), which was attributed to the greater surface area of lipid exposed to intestinal juices. The pH stat model also confirmed that emulsified corn oil was digestible, whereas emulsified mineral oil was indigestible. A rat feeding study showed that the bioavailability of the fatty acid and lipophilic nutraceutical in small intestinal tissues was highest when they were encapsulated within digestible oil droplets with the smallest size. This study provides important information for development of nanoemulsion-based delivery systems that increase oral bioavailability of lipophilic nutraceuticals.


Assuntos
Suplementos Nutricionais/análise , Ácidos Graxos/química , Ubiquinona/análogos & derivados , Animais , Disponibilidade Biológica , Química Farmacêutica , Óleo de Milho/química , Portadores de Fármacos/química , Emulsões/química , Feminino , Intestino Delgado/metabolismo , Óleo Mineral/química , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Ubiquinona/química , Ubiquinona/farmacocinética
2.
Cell Death Dis ; 3: e426, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23152062

RESUMO

Neuropathic pain is a well-known type of chronic pain caused by damage to the nervous system. Until recently, many researchers have primarily focused on identifying cellular or chemical sources of neuropathic pain or have approached neuropathic pain via the basis of biological study. We investigated whether both mmu-mir-23b (miR23b) and NADPH oxidase 4 (NOX4) antibody infusion can alleviate neuropathic pain by compensating for abnormally downregulated miR23b via reducing the expression of its target gene, NOX4, a reactive oxygen species (ROS) family member overexpressed in neuropathic pain. Ectopic miR23b expression effectively downregulated NOX4 and finally normalized glutamic acid decarboxylase 65/67 expression. Moreover, animals with neuropathic pain showed significantly improved paw withdrawal thresholds (PWTs) following miR23b infusion. Normalizing miR23b expression in tissue lesions, caused by neuropathic pain induction, reduced inflammatory mediators and increased several ROS scavengers. Moreover, γ-aminobutyric acid (GABA)ergic neurons coexpressed suboptimal levels of miR23b and elevated NOX4/ROS after pain induction at the cellular level. MiR23b finally protects GABAergic neurons against ROS/p38/c-Jun N-terminal kinase (JNK)-mediated apoptotic death. By evaluating the functional behavior of mice receiving pain/miR23b, normal/anti-miR23b, anti-miR23b/si-NOX4, pain/NOX4 antibody, pain/ascorbic acid, and pain/ascorbic acid/NOX4 antibody, the positive role of miR23b and the negative role of NOX4 in neuropathic pain were confirmed. Based on this study, we conclude that miR23b has a crucial role in the amelioration of neuropathic pain in injured spinal cord by inactivating its target gene, NOX4, and protection of GABAergic neurons from cell death. We finally suggest that infusion of miR23b and NOX4 antibody may provide attractive diagnostic and therapeutic resources for effective pain modulation in neuropathic pain.


Assuntos
Terapia de Alvo Molecular , NADPH Oxidases/genética , Neuralgia/genética , Neuralgia/terapia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos ICR , MicroRNAs/genética , MicroRNAs/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismos da Medula Espinal/metabolismo , Ácido gama-Aminobutírico/metabolismo
4.
Proc Natl Acad Sci U S A ; 97(17): 9783-8, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10931949

RESUMO

Expansins are cell-wall-loosening proteins that induce stress relaxation and extension of plant cell walls. To evaluate their hypothesized role in cell growth, we genetically manipulated expansin gene expression in Arabidopsis thaliana and assessed the consequent changes in growth and cell-wall properties. Various combinations of promoters were used to drive antisense and sense sequences of AtEXP10, which is maximally expressed in the growing leaf and at the base of the pedicel. Compared with controls, antisense lines had smaller rosettes because of shorter petioles and leaf blades and often acquired a twisted leaf morphology. Petiole cells from antisense plants were smaller than controls and their cell walls were significantly less extensible in vitro. Sense plants had slightly longer petioles, larger leaf blades, and larger cells than controls. Abscission at the base of the pedicel, where AtEXP10 is endogenously expressed, was enhanced in sense plants but reduced in antisense lines. These results support the concept that expansins function endogenously as cell-wall-loosening agents and indicate that expansins have versatile developmental roles that include control of organ size, morphology, and abscission.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Contagem de Células , Tamanho Celular , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Folhas de Planta/citologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , RNA Antissenso/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA de Plantas/análise , RNA de Plantas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transformação Genética , Transgenes/genética
5.
Planta ; 212(1): 85-92, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11219587

RESUMO

To investigate the evolutionary history of expansins and their role in cell elongation in early land plants, we isolated two alpha-expansin genes, Mq-EXP1 and Rd-EXP1, respectively, from the semiaquatic ferns Marsilea quacdrifolia L. and Regnellidium diphyllum Lindm. The deduced amino acid sequences of the fern expansins exhibit a high degree of identity to those of seed plants, showing that expansin genes were conserved during the evolution of vascular plants. Gel-blot analysis of M. quadrifolia and R. diphyllum genomic DNA indicated that, in both ferns, alpha-expansins are encoded by multigene families. Expression of alpha-expansin genes probed with Mq-EXP1 was confined to the elongating region of the Marsilea rachis. Cell-wall proteins of M. quadrifolia induced in-vitro extension of acidified cucumber cell walls. In R. diphyllum, expression of Rd-EXP1 increased when elongation of the rachis was enhanced by submergence or ethylene. These results indicate that alpha-expansins act as wall-loosening proteins in ferns, as has been proposed for angiosperms. In addition, Rd-EXP1 may play a role in mediating elongation of the rachis in submerged plants.


Assuntos
Proteínas de Plantas/genética , Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Evolução Biológica , DNA de Plantas , Etilenos/metabolismo , Dados de Sequência Molecular , Filogenia , Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/classificação , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , Homologia de Sequência de Aminoácidos
6.
Plant J ; 15(6): 805-12, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9807819

RESUMO

Expansins are a family of proteins capable of inducing stress relaxation of isolated cell walls. In earlier studies, we showed that the expression of expansin genes in deepwater rice (Oryza sativa L.) is regulated by developmental, hormonal and environmental stimuli. Here, we describe the spatial distribution pattern of expansin transcripts and proteins in tissues and organs of deepwater rice using in situ mRNA hybridization and immunohistochemical analysis. Expansin transcripts and proteins are present at high levels in the growing internodal epidermis, which has thick cell walls and acts, therefore, as a growth-limiting cell layer. Expansins are also concentrated in the differentiating vascular bundles of internodes. In the primary root, expansins are predominantly expressed in the tip region, particularly in the epidermis, differentiating vascular cylinder, and around the pericyle. Developing adventitious roots and lateral root primordia also contain high levels of expansin mRNA. In the shoot apex, expansin transcripts are abundant in the emerging leaf primordia. Our results indicate that expansins play an important role in the expansion and differentiation of plant tissues and organs.


Assuntos
Oryza/química , Proteínas de Plantas/análise , Hibridização In Situ , Oryza/genética , Proteínas de Plantas/genética , Raízes de Plantas/química , RNA Mensageiro/química , RNA de Plantas/química , Transcrição Gênica
7.
Plant Cell ; 9(9): 1661-71, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9338967

RESUMO

Expansins are a family of proteins that catalyze long-term extension of isolated cell walls. Previously, two expansin proteins have been isolated from internodes of deepwater rice, and three rice expansin genes, Os-EXP1, Os-EXP2, and Os-EXP3, have been identified. We report here on the identification of a fourth rice expansin gene, Os-EXP4, and on the expression pattern of the rice expansin gene family in deepwater rice. Rice expansin genes show organ-specific differential expression in the coleoptile, root, leaf, and internode. In these organs, there is increased expression of Os-EXP1, Os-EXP3, and Os-EXP4 in developmental regions where elongation occurs. This pattern of gene expression is also correlated with acid-induced in vitro cell wall extensibility. Submergence and treatment with gibberellin, both of which promote rapid internodal elongation, induced accumulation of Os-EXP4 mRNA before the rate of growth started to increase. Our results indicate that the expression of expansin genes in deepwater rice is differentially regulated by developmental, hormonal, and environmental signals and is correlated with cell elongation.


Assuntos
Oryza/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Dados de Sequência Molecular , Oryza/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos
8.
Plant Physiol ; 113(4): 1137-43, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9112771

RESUMO

Cell walls of deepwater rice (Oryza sativa L.) internodes undergo long-term extension (creep) when placed under tension in acidic buffers. This is indicative of the action of the cell wall-loosening protein expansin. Wall extension had a pH optimum of around 4.0 and was abolished by boiling. Acid-induced extension of boiled cell walls could be reconstituted by addition of salt-extracted rice or cucumber cell wall proteins. Cucumber expansin antibody recognized a single protein band of 24.5-kD apparent molecular mass on immunoblots of rice cell wall proteins. Expansins were partially purified by concanavalin A affinity chromatography and sulfopropyl (SP) cation-exchange chromatography. The latter yielded two peaks with extension activity (SP20 and SP29), and immunoblot analysis showed that both of these active fractions contained expansin of 24.5-kD molecular mass. The N-terminal amino acid sequence of SP20 expansin is identical to that deduced from the rice expansin cDNA Os-EXP1. The N-terminal amino acid sequence of SP29 expansin matches that deduced from the rice expansin cDNA Os-EXP2 in six of eight amino acids. Our results show that two expansins occur in the cell walls of rice internodes and that they may mediate acid-induced wall extension.


Assuntos
Oryza/fisiologia , Proteínas de Plantas/biossíntese , Aclimatação , Sequência de Aminoácidos , Soluções Tampão , Parede Celular/fisiologia , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Concanavalina A , Cucumis sativus , Eletroforese em Gel de Poliacrilamida , Água Doce , Concentração de Íons de Hidrogênio , Immunoblotting , Dados de Sequência Molecular , Lectinas de Plantas , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Homologia de Sequência de Aminoácidos
9.
Plant Physiol ; 113(4): 1145-1151, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12223665

RESUMO

The distribution and activity of the cell wall-loosening protein expansin is correlated with internodal growth in deepwater rice (Oryza sativa L.). Acid-induced extension of native cell walls and reconstituted extension of boiled cell walls were confined to the growing region of the internode, i.e. to the intercalary meristem (IM) and the elongation zone. Immunolocalization by tissue printing and immunoblot analysis, using antibody against cucumber expansin 29 as a probe, confirmed that rice expansin occurred primarily in the IM and elongation zone. Rice expansin was localized mainly around the vascular bundles at the base of the IM and along the inner epidermal cell layer surrounding the internodal cavity. Submergence greatly promoted the growth of rice internodes, and cell walls of submerged internodes extended much more in response to acidification than did the cell walls of air-grown internodes. Susceptibility of cell walls to added expansin was also increased in submerged internodes, and analysis by immunoblotting showed that cell walls of submerged internodes contained more expansin than did cell walls of air-grown internodes. Based on these data, we propose that expansin is involved in mediating rapid internodal elongation in submerged deepwater rice internodes.

10.
Laryngoscope ; 103(5): 529-32, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8483370

RESUMO

Recent investigations revealed that interleukin-1 can promote bone resorption by activating osteoclasts. The authors' immunocytochemical studies with monoclonal antibody against human interleukin-1 localized interleukin-1 at the bone resorption site of the squamous carcinomas as well as within the squamous carcinomas. In addition, Western blotting and dot blotting methods were used to isolate interleukin-1 from the extracts of the squamous carcinomas in the head and neck. Finding interleukin-1, a potent bone resorption-stimulating factor, in squamous carcinomas suggests that interleukin-1 might play an important role in the extensive local bone destruction seen in the head and neck patients with squamous carcinomas.


Assuntos
Carcinoma de Células Escamosas/química , Neoplasias de Cabeça e Pescoço/química , Interleucina-1/análise , Western Blotting , Imunofluorescência , Humanos , Immunoblotting , Técnicas Imunoenzimáticas
11.
Ann Otol Rhinol Laryngol ; 98(1 Pt 1): 59-65, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910191

RESUMO

Four cases of primary squamous cell carcinoma of the thyroid gland are reported. Thorough evaluation confirmed these lesions to be of primary thyroid origin rather than from metastasis or direct invasion from contiguous structures. These cases illustrate the aggressive nature of the disease and the propensity for local and distant metastases. The clinicopathologic data presented here underscore the challenge in diagnosis and treatment of this rare entity.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Idoso , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia
12.
Laryngoscope ; 98(1): 35-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3336259

RESUMO

Fine needle aspiration (FNA) biopsy is gaining in popularity among all diagnostic tests used in the evaluation of patients for thyroidectomy. Its safety and accuracy have been well documented, but criteria regarding when FNA is appropriate are lacking. We retrospectively reviewed our experience with 408 consecutive patients evaluated for thyroid surgery. Two hundred seventy-three ultimately underwent thyroidectomy; 100 of these had preoperative FNA. An additional 135 patients underwent FNA without surgery. Patients who benefited from FNA were those in whom cytologic findings led to surgery for otherwise unsuspected malignancy (15), and those with asymptomatic benign nodules who avoided unnecessary thyroidectomy on the basis of FNA findings (96). FNA is superfluous when clinical conditions mandate surgery. These include nodules that arouse clinical suspicion of malignancy, massive nodules that cause aerodigestive tract compression or cosmetic disfigurement, and nodules extending into the mediastinum. All patients with asymptomatic, clinically benign thyroid nodules should undergo FNA biopsy, as approximately 50% can anticipate significant benefit from the procedure.


Assuntos
Biópsia por Agulha , Neoplasias da Glândula Tireoide/diagnóstico , Tireoidectomia , Citodiagnóstico , Humanos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia
13.
Otolaryngol Head Neck Surg ; 94(3): 282-7, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3083354

RESUMO

Goiters that descend into the mediastinum can cause respiratory embarrassment, dysphagia, vascular compression, vocal cord paralysis, and sudden death. Although many such goiters remain clinically silent, their ability to produce sudden and unpredictable respiratory distress is well known. The condition was not considered uncommon in the first half of the twentieth century; some authors reported series of hundreds of thyroidectomies for intrathoracic goiter. Though seen less frequently today, the only effective treatment for mediastinal goiter is surgical removal. We report our experience with the management of 70 consecutive patients with substernal or intrathoracic goiters. The clinical presentation, preoperative evaluation, operative technique, and results and complications of therapy are discussed. Consideration is also given to the pathogenesis of intrathoracic extension. The transcervical approach for resection is emphasized--even goiters extending to the aortic arch were safely removed without requiring sternotomy. A multidisciplinary team approach, including the surgeon, anesthesiologist, and endocrinologist, is essential. Because of more conservative trends in the selection of patients for thyroidectomy, the incidence of mediastinal goiter may be increasing.


Assuntos
Bócio Subesternal/cirurgia , Adulto , Idoso , Feminino , Bócio Subesternal/diagnóstico por imagem , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Tomografia Computadorizada por Raios X
15.
Laryngoscope ; 93(1): 17-9, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6823171

RESUMO

Since the concept of myocutaneous flap reconstruction of the head and neck region was introduced it has opened a new approach to surgical management in this area. This flap not only reduced the number of operations as compared to "staged procedure", but also reduced the costs of medical care. We are, however, experiencing significant failures as the applications of this flap are extended. This paper reviews our experience with myocutaneous flaps in 15 partial and total failures. An evaluation of these failures reveals that most occurred 1 1/2 to 3 weeks after reconstruction. The factors predisposing to failure seem related more to technical errors rather than to general factors. Diabetes, peripheral vascular disease, malnutrition and low hemoglobin, and low blood pressure were not major contributors to the failures in our series. Local factors predisposing to failure of myocutaneous flaps can be divided into two large categories--arterial failure and venous failure. In our series of unsuccessful myocutaneous flaps, the major factors appeared to be venous stasis leading to arterial insufficiency. All failures had developed after the initial critical period of flap survival (7-10 days). The following techniques showed an especially high rate of failure: 1. SCM--myocutaneous flap to resurface floor of mouth. 2. Tubed pectoralis myocutaneous flap to reconstruct pharynx and esophagus. 3. Flaps developed with very narrow vascular pedicles. Individual cases representing delayed failure are presented.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Retalhos Cirúrgicos , Neoplasias Esofágicas/cirurgia , Estudos de Avaliação como Assunto , Sobrevivência de Enxerto , Humanos , Métodos , Soalho Bucal , Neoplasias Bucais/cirurgia , Músculos , Músculos Peitorais , Neoplasias Faríngeas/cirurgia , Complicações Pós-Operatórias , Fístula das Glândulas Salivares/etiologia
16.
Ann Surg ; 183(1): 10-2, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1247295

RESUMO

A review of 700 parotidectomies showed that 98 procedures were performed for parotid space tumors of non-salivary origin. The clinical presentation in this group of patients did not differ significantly from the larger group of salivary tumors except for a higher incidence (12%) of the former in the younger age group. Of the 98 cases, 54 proved to be lymph node tumors, both neoplastic and inflammatory and 44 were tumors of various somatic origins. Among the latter group, bone and joint tumors, vascular lesions and some connective tissue tumors may be recognized preoperatively. Generally, however, the entire group of non-salivary tumors can be distinguished only intra-operatively, if at all. Correct recognition may lead to variations in operative techniques and extent of resection.


Assuntos
Neoplasias Bucais , Adulto , Diagnóstico Diferencial , Humanos , Linfadenite/diagnóstico , Linfadenite/cirurgia , Linfoma/diagnóstico , Linfoma/cirurgia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/cirurgia , Metástase Neoplásica , Neoplasias Parotídeas/diagnóstico , Doenças das Glândulas Salivares/diagnóstico
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