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1.
Plast Reconstr Surg ; 139(3): 738-748, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28234857

RESUMO

BACKGROUND: The two major perforators supplying the superficial circumflex iliac artery perforator flap are the medial (superficial) and lateral (deep) perforators; however, they lack detailed description. The purpose of this study was to clarify the anatomy. METHODS: In a prospective analysis of 142 patients, computed tomographic angiograms of 284 superficial circumflex iliac artery perforator regions were evaluated, and 142 superficial circumflex iliac artery perforator flaps were surgically correlated. The origin of the superficial circumflex iliac artery, the origin of the medial perforator, the location where it penetrates the deep fascia, and its pattern of pathway after penetration of the superficial fascia were evaluated. RESULTS: There was 100 percent correlation between computed tomographic angiogram and surgical findings. The superficial circumflex iliac artery originates mostly from the femoral artery in 84.8 percent. The medial perforator originated from the superficial circumflex iliac artery in 94 percent. The medial perforator typically penetrated the deep fascia within an oval of 4.2 × 2 cm located 4.5 cm lateral and 1.5 cm superior from the pelvic tubercle. After passing the superficial fascia, the medial perforator either anchored directly into skin (56 percent) or traveled in an axial pattern (44 percent) beyond the anterior superior iliac spine. CONCLUSIONS: Despite the origin of the medial perforator, it was constantly observed penetrating the deep fascia. However, the pathway of the medial perforator can be either anchoring directly into the dermis or extending as an axial pattern artery, implicating a different effect on the survival of the flap. These new findings will allow better understanding for elevating the superficial circumflex iliac artery perforator flap based on the medial perforator.


Assuntos
Angiografia/métodos , Angiografia por Tomografia Computadorizada , Artéria Ilíaca/diagnóstico por imagem , Retalho Perfurante/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Neoplasias de Tecidos Moles/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
2.
ACS Appl Mater Interfaces ; 8(34): 22484-92, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27504951

RESUMO

Density dependent growth and optical properties of periodic arrays of GaAs nanowires (NWs) by fast selective area growth MOVPE are investigated. As the period of the arrays is decreased from 500 nm down to 100 nm, a volume growth enhancement by a factor of up to four compared with the growth of a planar layer is observed. This increase is explained as resulting from increased collection of precursors on the side walls of the nanowires due to the gas flow redistribution in the space between the NWs. Normal spectral reflectance of the arrays is strongly reduced compared with a flat substrate surface in all fabricated arrays. Electromagnetic modeling reveals that this reduction is caused by antireflective action of the nanowire arrays and nanowire-diameter dependent light absorption. Irrespective of the periodicity and diameter, Raman scattering and grazing angle X-ray diffraction show signal from zinc blende and wurtzite phases, the latter originating from stacking faults as observed by high resolution transmission electron microscopy. Raman spectra contain intense surface phonons peaks, whose intensity depends strongly on the nanowire diameters as a result of potential structural changes and as well as variations of optical field distribution in the nanowires.

3.
Mater Sci Eng C Mater Biol Appl ; 46: 276-80, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25491988

RESUMO

Ten different Ag dot arrays (16 to 625 microstructured dots per square mm) were fabricated on a continuous Au thin film and for comparison also on Ti film by sputter deposition and photolithographic patterning. To analyze the antibacterial activity of these microstructured films Escherichia coli and Staphylococcus aureus were placed onto the array surfaces and cultivated overnight. To analyze the viability of planktonic as well as surface adherent bacteria, the applied bacterial fluid was subsequently aspirated, plated on blood agar plates and adherent bacteria were detected by fluorescence microscopy. A particular antibacterial effect towards both bacterial strains was induced by Ag dot arrays on fabricated Au thin film (sacrificial anode system for Ag), due to the release of Ag ions from dissolution of Ag dots in contrast to Ag dot arrays fabricated on the Ti thin films (non-sacrificial anode system for Ag) which remained intact to the original dot shape. The required number of Ag dots on gold film to achieve complete bactericidal effects for both bacterial strains was seven times lower than that observed with Ag dot arrays on Ti film.


Assuntos
Antibacterianos/farmacologia , Eletrodos , Ouro/farmacologia , Prata/farmacologia , Antibacterianos/química , Células Cultivadas , Ouro/química , Humanos , Prata/química
4.
Invest Ophthalmol Vis Sci ; 52(10): 7090-7, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21810978

RESUMO

PURPOSE: To assess the effect of transforming growth factor (TGF)-ß inhibitor peptides (P17 and P144) on the development of laser-induced choroidal neovascularization (LI-CNV) in a rat model. METHODS: Sixty-one Long-Evans rats underwent diode LI-CNV model. Forty-eight hours later, treatment was administered. The intravenous control group (IV-control) and intravenous P17 group (IV-17) received five doses (0.2 mg every 72 hours) of vehicle and P17, respectively. Four groups received intravitreal injections of P17 low-dose (LD-17; 1 mg/mL) and high-dose (HD-17; 20 mg/mL) and P144 low-dose (LD-144; 1 mg/mL) and high-dose (HD-144; 3 mg/mL), and fellow eyes received vehicle. CNV evolution was assessed weekly by fluorescein angiography (FA). After death, VEGF, TGF-ß and PDGF protein levels were measured by ELISA in RPE and retina homogenates. Data were analyzed with commercially available statistical analysis software. RESULTS: The mean CNV area, measured in pixels, was significantly lower at the second and fourth weeks in IV-17 (P < 0.05) and from the second week in HD-17 (P < 0.05), whereas LD-144 and HD-144 showed significant differences at every time point (P < 0.05). LD-17 showed significantly lower protein levels of TGF-ß in retina and PDGF in RPE (P < 0.05), whereas HD-17 showed lower levels of VEGF (RPE and retina; P < 0.05), TGF-ß (RPE and retina; P < 0.05), and PDGF (RPE; P < 0.05). HD-144 showed lower VEGF levels in the retina (P < 0.05). CONCLUSIONS: TGF-ß inhibition with these peptides represents a promising new therapeutic line for CNV targeting a different pathway than current therapies. More studies are needed to assess this effect on early CNV, alone or in combination with anti-VEGF.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Modelos Animais de Doenças , Fragmentos de Peptídeos/farmacologia , Peptídeos/farmacologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Ensaio de Imunoadsorção Enzimática , Angiofluoresceinografia , Injeções Intravenosas , Injeções Intravítreas , Fotocoagulação a Laser , Lasers Semicondutores , Masculino , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Ratos Long-Evans , Receptores de Fatores de Crescimento Transformadores beta , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
J Neuroendocrinol ; 21(1): 57-67, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19094094

RESUMO

Leptin, an adipocyte-derived hormone, regulates food intake and body weight by acting principally on the hypothalamus, which displays the highest expression of leptin receptor (Ob-R). Nevertheless, other regions of the brain express Ob-R and constitute leptin's target sites. The dorsal vagal complex (DVC), an integrative centre of autonomic functions located in the caudal brainstem, is one of these structures. Leptin, by acting through the DVC, affects autonomic and neuroendocrine functions, such as control of food intake and gastric motility. In the present study, we observed Ob-R labelling within the DVC in cells that correspond to neuronal cell bodies. We showed for the first time Ob-R expression in a subpopulation of glial fibrillary acid protein positive cells located at the border between the area postrema and the nucleus tractus solitarius (NTS). These glial cells exhibit an atypical morphology consisting of unbranched processes that radiate rostro-caudally from the fourth ventricle wall. In vitro, the glial cells exhibited both long and short Ob-R expression with a preferential expression of the Ob-Ra and-f isoforms. Interestingly, using i.v and i.c.v. injection of the fluorescent tracer hydroxystilbamidine, we provided evidence that these cells may constitute a diffusion barrier which might regulate entry of molecules into the NTS. Finally, modulation of energy status, by acute or chronic reduction of food intake, modulated especially the short Ob-R isoforms in the DVC. In the light of these results, we hypothesise that Ob-R positive glial cells of the DVC participate in the transport of leptin into the brainstem and thus contribute to regulation of energy homeostasis.


Assuntos
Metabolismo Energético , Homeostase , Neuroglia/metabolismo , Isoformas de Proteínas/metabolismo , Receptores para Leptina/metabolismo , Núcleo Solitário/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Leptina/metabolismo , Masculino , Neuroglia/citologia , Estado Nutricional , Isoformas de Proteínas/genética , Ratos , Ratos Wistar , Receptores para Leptina/genética , Núcleo Solitário/citologia , Estilbamidinas/metabolismo
6.
Invest Ophthalmol Vis Sci ; 49(3): 968-74, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18326720

RESUMO

PURPOSE: To assess the reproducibility of the ocular response analyzer (ORA) in nonoperated eyes and the impact of corneal biomechanical properties on intraocular pressure (IOP) measurements in normal and glaucomatous eyes. METHODS: In the reliability study, two independent examiners obtained repeated ORA measurements in 30 eyes. In the clinical study, the examiners analyzed ORA and IOP-Goldmann values from 220 normal and 42 glaucomatous eyes. In both studies, Goldmann-correlated IOP measurement (IOP-ORAg), corneal-compensated IOP (IOP-ORAc), corneal hysteresis (CH), and corneal resistance factor (CRF) were evaluated. IOP differences of 3 mm Hg or greater between the IOP-ORAc and IOP-ORAg were considered outcome significant. RESULTS: Intraexaminer intraclass correlation coefficients and interexaminer concordance correlation coefficients ranged from 0.78 to 0.93 and from 0.81 to 0.93, respectively, for all parameters. CH reproducibility was highest, and the IOP-ORAg readings were lowest. The median IOP was 16 mm Hg with the Goldmann tonometer, 14.5 mm Hg with IOP-ORAg (P < 0.001), and 15.7 mm Hg with IOP-ORAc (P < 0.001). Outcome-significant results were found in 77 eyes (29.38%). The IOP-ORAc, CH, and CRF were correlated with age (r = 0.22, P = 0.001; r = -0.23, P = 0.001; r = -0.14, P = 0.02, respectively), but not the IOP-ORAg or IOP-Goldmann. CONCLUSIONS: The ORA provides reproducible corneal biomechanical and IOP measurements in nonoperated eyes. Considering the effect of ORA, corneal biomechanical metrics produces an outcome-significant IOP adjustment in at least one quarter of glaucomatous and normal eyes undergoing noncontact tonometry. Corneal viscoelasticity (CH) and resistance (CRF) appear to decrease minimally with increasing age in healthy adults.


Assuntos
Córnea/fisiologia , Glaucoma de Ângulo Aberto/diagnóstico , Pressão Intraocular/fisiologia , Tonometria Ocular , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Estudos Transversais , Tecido Elástico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes
7.
Prev Cardiol ; 4(3): 109-114, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11828186

RESUMO

The authors examined the distribution of, and risk factors associated with, the inflammatory marker C-reactive protein (CRP) among a large sample of non-institutionalized American adults aged 30-74 years of age, and its relation to estimated 10-year coronary heart disease risk. The population studied comprised 4472 men and 5212 women aged 30-74 years, without coronary heart disease, who had CRP measurements in the Third National Health and Nutrition Examination Survey (NHANES III). The 10-year risk of coronary heart disease was estimated from Framingham risk factor algorithms among those with CRP levels of less-than-or-equal0.21 mg/dL, >0.21 to <0.5mg/dL, 0.5 to <1.0 mg/dL, and greater-than-or-equal1.0 mg/dL. Mean (SD) levels of CRP were 0.41 (0.64) mg/dL in men and 0.55 (0.91) mg/dL in women. Levels of at least 1 mg/dL were measured in 6.4% of men and 12.9% of women. CRP levels were highest among non-Hispanic black men and Mexican-American women. According to multiple logistic regression analysis, cigarette smoking and increased age, body mass index, and systolic blood pressure in men, and body mass index and diabetes in women, were strongly associated with a greater likelihood of CRP levels of greater-than-or-equal1.0 mg/dL (p<0.001). Among persons with CRP levels of less-than-or-equal0.21 mg/dL, >0.21 to <0.5 mg/dL, 0.5 to <1.0 mg/dL and greater-than-or-equal1.0 mg/dL, the 10-year estimated risk of coronary heart disease were 13.4%, 17.6%, 19.6%, and 21.1% among men, respectively, and 2.7%, 3.6%, 4.1% and 4.3% among women, respectively (both p<0.001 across CRP categories); higher risks across CRP groups were also found among ethnic/gender subgroups. CRP remained a significant predictor of coronary heart disease risk in unadjusted and age-adjusted analyses. Conclusion. Elevation of CRP is associated with several major coronary heart disease risk factors and with unadjusted and age-adjusted projections of 10-year coronary heart disease risk in both men and women. (c)2001 CHF, Inc. Presented at the Fifth International Conference on Preventive Cardiology, Osaka, Japan, May, 2001.

8.
Brain Res Dev Brain Res ; 112(2): 281-5, 1999 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-9878786

RESUMO

Synaptophysin (SY) is a major integral membrane protein of small synaptic vesicles. In the present study, SY immunohistochemistry was used to investigate the postnatal development of the rat nucleus tractus solitarii (NTS) and nucleus ambiguus/ventrolateral medulla (NA/VLM). Whatever the age of the animal, SY immunoreactivity showed a typical pattern of punctate staining reminiscent of presynaptic terminal labeling. In the NTS and the NA/VLM, SY immunoreactive puncta were few at birth and increased in number during the first postnatal days. These changes were quantified by measuring the volumetric fraction occupied by SY immunoreactive puncta at various postnatal ages. Using volumetric fraction data, an index of the total volume occupied SY immunoreactivity in each region was then calculated. Between birth and adulthood, this index increased by 6-fold in the NTS and by 7-fold in the NA/VLM, suggesting that most of the synaptic development of these regions occurs postnatally.


Assuntos
Envelhecimento/metabolismo , Animais Recém-Nascidos/metabolismo , Bulbo/metabolismo , Núcleo Solitário/metabolismo , Sinaptofisina/metabolismo , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Feminino , Imuno-Histoquímica , Masculino , Bulbo/crescimento & desenvolvimento , Terminações Pré-Sinápticas/metabolismo , Ratos , Núcleo Solitário/crescimento & desenvolvimento
9.
Cryobiology ; 34(3): 214-39, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9160994

RESUMO

To test cool-warm protocols for storing peripheral nerves, 4-cm-long-nerve segments were removed from the hindleg of adult rats and cryopreserved using a vitrification solution (or cryoprotective mixture) containing a mixture of polyalcohols (2,3-butanediol, 1,2-propanediol, polyethylene glycol, and Belzer U.W. medium). Schwann cell viability and morphology were studied with regard to the effect of (i) cryoprotective mixture concentration (100, 50, and 30% diluted in human serum albumin at 4%), (ii) duration of exposure (10, 15, or 30 min in a single step) of nerves to the cryoprotective mixture, (iii) cooling rate (F1/F2, F3, and F4: 3, 12, and 231 degrees C/min, respectively), and (iv) type of replacement of cryoprotectant (T1, one step; or T2, perfusion) after warming. Nerves exposed 10 min to cryoprotective mixture 50% (2,3-butanediol, 1.926 mol.liter-1; 1,2-propanediol, 3.063 mol.liter-1; polyethylene glycol, 0.084 mol.liter-1; and Belzer U.W., 22.4 mosm-1) and cooled-warmed with the F2/F3/F4-T2 protocols contained live and correctly cryopreserved Schwann cells. The capacity of these cryopreserved nerve segments (n = 6) to be subsequently repopulated by regenerating axons from central neurons was compared to that of fresh nerves when used as peripheral nerve autografts implanted within the spinal cord at the level of the descending respiratory pathways. All cryopreserved nerve grafts were successfully reinnervated by regenerated central axons. Unitary spontaneous action potentials propagated along these axons were assessed by recording the discharge of tested nervous filaments (T) from the grafts in artificially ventilated and paralyzed animals. Out of 535 T, 32 (6 +/- 1.2%) presented spontaneous unitary activity with respiratory (R, n = 2) and nonrespiratory (NR, n = 30) pattern of discharge. The T mean number, the occurrence rate referenced to the total number of T (R/T, NR/T, and R + NR/T) and the mean number of spontaneous units (R, NR, R + NR) were compared to those of fresh spinal peripheral nerve grafts. Except for T, cryopreserved peripheral nerve grafts contained statistically significantly (P < 0.05) less spontaneous R and NR unitary activity, which represented, respectively, 6.2 +/- 6.2 and 26.8 +/- 5.7% of that found in the control group. These data indicate that nerves cryopreserved with the protocols described above contain viable Schwann cells which constitute a suitable support to induce regeneration of central fibers. The effectiveness of nerve cryopreservation by vitrification is discussed with regard to Schwann cell viability following cool-warm protocols and to subsequent reinnervation of the cryopreserved peripheral nerve grafts.


Assuntos
Axônios/fisiologia , Criopreservação/métodos , Regeneração Nervosa/fisiologia , Nervos Periféricos/transplante , Animais , Axônios/ultraestrutura , Sobrevivência Celular , Sistema Nervoso Central/fisiologia , Sistema Nervoso Central/ultraestrutura , Crioprotetores , Eletrofisiologia , Estudos de Avaliação como Assunto , Feminino , Humanos , Nervos Periféricos/fisiologia , Nervos Periféricos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Células de Schwann/citologia , Transplante Autólogo
10.
Neurosci Lett ; 114(3): 253-8, 1990 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-2402334

RESUMO

A selective retrograde labeling study was performed using [3H]D-aspartate to identify putative glutamatergic and/or aspartatergic primary vagal afferent fibers. Unilateral microinjection of [3H]D-aspartate into the nucleus tractus solitarii resulted in clear visible labeling of a fraction of the neuronal cell-bodies in the nodose ganglia. The labeled cell-bodies were randomly distributed in the ganglion and more numerous labeled neurons were detected in the ipsilateral than in the contralateral ganglion (4.93% and 0.98% of the neurons sampled within the ipsi- and contralateral ganglia, respectively). These results strongly suggest that primary vagal afferent fibers may utilize excitatory amino acids as transmitters.


Assuntos
Tronco Encefálico/metabolismo , Neurônios Aferentes/metabolismo , Nervo Vago/metabolismo , Animais , Ácido Aspártico , Tronco Encefálico/citologia , Glutamatos/metabolismo , Neurônios Aferentes/citologia , Ratos , Ratos Endogâmicos , Trítio , Nervo Vago/citologia
11.
Ars cvrandi ; 16(8): 101-10, passim, 1983.
Artigo em Português | LILACS | ID: lil-17710
12.
Ars cvrandi ; 16(5): 122-6, passim, 1983.
Artigo em Português | LILACS | ID: lil-16874
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