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1.
Transplant Proc ; 50(3): 939-942, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29661466

RESUMO

We report a very rare case of pulmonary chromomycosis caused by Scedosporium prolificans that developed after lung transplantation and was successfully treated with endobronchial topical amphotericin B instillation. The subject was a woman in her 50s with a history of bilateral lobar lung transplantation from living donors for idiopathic pulmonary hypertension. Eight years after the lung transplantation, chest radiography X-ray and computed tomography showed an abnormal shadow in the right lung. Bronchoscopic findings showed obstruction by a fungal component at the laterobasal bronchus B9. She was diagnosed with pulmonary chromomycosis after S. prolificans was detected in the bronchial aspirate. Systemic antifungal treatment with itraconazole was ineffective. Therefore, we administered topical amphotericin B weekly via endobronchial instillation and replaced oral itraconazole with voriconazole. The endobronchial procedure was safe and tolerable. Bronchial obstruction improved after three 3 instillations. We continued topical amphotericin B instillation once every 3 months for 2 years, and the abnormal shadow nearly disappeared. This case report describes infection by S. prolificans, which rarely becomes an etiologic agent in lung transplant patients, and shows that endobronchial topical amphotericin B instillation is a therapeutic option when systemic antifungal treatment is ineffective.


Assuntos
Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Cromoblastomicose/tratamento farmacológico , Pneumopatias Fúngicas/tratamento farmacológico , Transplante de Pulmão/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Administração Tópica , Broncoscopia/métodos , Cromoblastomicose/microbiologia , Feminino , Humanos , Pulmão/microbiologia , Pneumopatias Fúngicas/microbiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/microbiologia , Scedosporium
2.
Anat Histol Embryol ; 44(2): 157-60, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24809824

RESUMO

We recently reported the absence of the articular disc, which is a constant structure in mammals, in the temporomandibular joint of the adult Tasmanian devil. However, whether the articular disc disappears with growth of the animal was unknown. The aim of this study was to determine whether a pouch young of the Tasmanian devil has the articular disc. The temporomandibular joint of a fresh carcass of the pouch young, whose crown-rump length was 43 mm, was examined microscopically and by microcomputed tomography. The absence of the articular disc in the pouch young temporomandibular joint was histologically confirmed. It is suggested that the articular disc of the Tasmanian devil is naturally absent.


Assuntos
Marsupiais/anatomia & histologia , Articulação Temporomandibular/ultraestrutura , Animais , Marsupiais/crescimento & desenvolvimento , Pele , Articulação Temporomandibular/diagnóstico por imagem , Microtomografia por Raio-X
3.
Int J Oral Maxillofac Surg ; 43(6): 692-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24503102

RESUMO

The use of stereotactic body radiation therapy is rapidly increasing among patients with lung cancer not amenable to surgery. The authors report their experience using the CyberKnife system (Accuray Inc., Sunnyvale, CA, USA) as a treatment option for synchronous cancer of oral squamous cell carcinoma and a malignant lung tumour. An 88-year-old woman with two cancers (oral and lung masses) underwent CyberKnife treatment, with fiducial gold pins implanted using bronchoscopy. Toxicity was limited, and at the 2-year follow-up the lesions had not recurred.


Assuntos
Neoplasias Gengivais/cirurgia , Neoplasias Pulmonares/cirurgia , Neoplasias Maxilares/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Radiocirurgia/métodos , Radioterapia Guiada por Imagem/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Idoso de 80 Anos ou mais , Broncoscopia , Feminino , Marcadores Fiduciais , Neoplasias Gengivais/patologia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Maxilares/patologia , Imagem Multimodal , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/patologia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
4.
Oral Dis ; 20(6): 582-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24112848

RESUMO

OBJECTIVE: Periodontal ligament (PDL) cells and their substrates play key roles in periodontal regeneration. However, there has been no report on the use of amniotic membrane (AM) as a substrate for culturing PDL cells. In the current study, we conducted an analysis of PDL cells cultivated on AM to determine the distribution of factors responsible for maintaining the characteristics of PDL. MATERIALS AND METHODS: Amniotic membrane was obtained from women undergoing cesarean sections, whereas PDL tissue was obtained from human maxillary third molars. The harvested PDL cells were maintained in explant culture for three or four passages, following which they were cultured on AM. RESULTS: After 3 weeks of culture, the PDL cells had grown well on AM. Immunofluorescence showed that these cells were capable of proliferating and potentially maintaining their PDL-like properties. In addition, strong cell-cell adhesion structures, namely desmosomes and tight junctions, were shown to be present between cells. Electron microscopy images showed that the cultured PDL cells had differentiated and proliferated on AM with lateral conjugation and adhesion to AM. CONCLUSION: We conclude that AM may represent a suitable substrate for culturing PDL cells and that PDL cells cultured on AM show sheet formation.


Assuntos
Âmnio , Meios de Cultura , Ligamento Periodontal/citologia , Adulto , Adesão Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas/fisiologia , Células Cultivadas/ultraestrutura , Técnicas de Cocultura , Desmossomos/ultraestrutura , Feminino , Humanos , Masculino , Junções Íntimas/ultraestrutura , Adulto Jovem
5.
Opt Lett ; 36(12): 2327-9, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21686009

RESUMO

We demonstrated an InP-based optical multimode interferometer (MMI) combined with metamaterials consisting of minute split-ring resonators (SRRs) arrayed on the MMI. The MMI could operate at an optical fiber communication wavelength of 1.5 µm. Magnetic resonance occurred between the SRR metamaterial and light at 1.5 µm, and the relative permeability of the metamaterial increased to 2.4 around this wavelength. This result shows that it is possible to use new materials with nonunity permeability to construct semiconductor-based photonic devices.

6.
Ecology ; 89(2): 567-80, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18409445

RESUMO

Scaling relationships between mean body masses and abundances of species in multitrophic communities continue to be a subject of intense research and debate. The top-down mechanism explored in this paper explains the frequently observed inverse linear relationship between body mass and abundance (i.e., constant biomass) in terms of a balancing of resource biomasses by behaviorally and evolutionarily adapting foragers, and the evolutionary response of resources to this foraging pressure. The mechanism is tested using an allometric, multitrophic community model with a complex food web structure. It is a statistical model describing the evolutionary and population dynamics of tens to hundreds of species in a uniform way. Particularities of the model are the detailed representation of the evolution and interaction of trophic traits to reproduce topological food web patterns, prey switching behavior modeled after experimental observations, and the evolutionary adaptation of attack rates. Model structure and design are discussed. For model states comparable to natural communities, we find that (1) the body-mass abundance scaling does not depend on the allometric scaling exponent of physiological rates in the form expected from the energetic equivalence rule or other bottom-up theories; (2) the scaling exponent of abundance as a function of body mass is approximately -1, independent of the allometric exponent for physiological rates assumed; (3) removal of top-down control destroys this pattern, and energetic equivalence is recovered. We conclude that the top-down mechanism is active in the model, and that it is a viable alternative to bottom-up mechanisms for controlling body-mass-abundance relations in natural communities.


Assuntos
Biomassa , Ecossistema , Comportamento Alimentar/fisiologia , Cadeia Alimentar , Modelos Biológicos , Animais , Biodiversidade , Tamanho Corporal , Preferências Alimentares , Densidade Demográfica , Dinâmica Populacional , Especificidade da Espécie
7.
IEEE Trans Haptics ; 1(1): 9-18, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-27788082

RESUMO

Weight perception has been of great interest for over three centuries. Most research has been concerned with the weight of static objects, and some illusions have been discovered. Here, we show a new illusion related to the perception of the heaviness of oscillating objects. We performed experiments that involved comparing the weight of two objects of identical physical appearance but with different gross weights and oscillation patterns (vibrating vertically at frequencies of 5 or 9 cycles per second with symmetric and asymmetric acceleration patterns). The results show that the perceived weight of an object vibrating with asymmetric acceleration increases compared to that with symmetric acceleration when the acceleration peaks in the gravity direction. In contrast, almost no heaviness perception change was observed in the anti-gravity direction. We speculate that the reason for the divergence between these results is caused by the differential impact of these two hypothesized perceptual mechanisms as follows: the salience of pulse stimuli appears to have a strong influence in the gravity direction, whereas filling-in could explain our observations in the anti-gravity direction. The study of this haptic illusion can provide valuable insights into not only human perceptual mechanisms but into the design of ungrounded haptic interfaces.

8.
Appl Opt ; 46(23): 5784-91, 2007 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-17694128

RESUMO

We developed a 1.5-microm band TM-mode waveguide optical isolator that makes use of the nonreciprocal-loss phenomenon. The device was designed to operate in a single mode and consists of an InGaAlAs/InP ridge-waveguide optical amplifier covered with a ferromagnetic MnAs layer. The combination of the optical waveguide and the magnetized ferromagnetic metal layer produces a magneto-optic effect called the nonreciprocal-loss phenomenon--a phenomenon in which the propagation loss of light is larger in backward propagation than it is in forward propagation. We propose the guiding design principle for the structure of the device and determine the optimized structure with the aid of electromagnetic simulation using the finite-difference method. On the basis of the results, we fabricated a prototype device and evaluated its operation. The device showed an isolation ratio of 7.2 dB/mm at a wavelength from 1.53 to 1.55 microm. Our waveguide isolator can be monolithically integrated with other waveguide-based optical devices on an InP substrate.

9.
J Theor Biol ; 243(2): 261-72, 2006 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-16890962

RESUMO

The trophic link density and the stability of food webs are thought to be related, but the nature of this relation is controversial. This article introduces a method for estimating the link density from diet tables which do not cover the complete food web and do not resolve all diet items to species level. A simple formula for the error of this estimate is derived. Link density is determined as a function of a threshold diet fraction below which diet items are ignored ("diet partitioning function"). Furthermore, analytic relationships between this threshold-dependent link density and the generality distribution of food webs are established. A preliminary application of the method to field data suggests that empirical results relating link density to diversity might need to be revisited.


Assuntos
Dieta , Cadeia Alimentar , Modelos Biológicos , Animais , Biodiversidade , Entropia , Especificidade da Espécie
10.
J Theor Biol ; 241(3): 552-63, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16466654

RESUMO

Food webs of habitats as diverse as lakes or desert valleys are known to exhibit common "food-web patterns", but the detailed mechanisms generating these structures have remained unclear. By employing a stochastic, dynamical model, we show that many aspects of the structure of predatory food webs can be understood as the traces of an evolutionary history where newly evolving species avoid direct competition with their relatives. The tendency to avoid sharing natural enemies (apparent competition) with related species is considerably weaker. Thus, "experts consuming families of experts" can be identified as the main underlying food-web pattern. We report the results of a systematic, quantitative model validation showing that the model is surprisingly accurate.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Animais , Evolução Biológica , Comportamento Predatório , Reprodutibilidade dos Testes , Processos Estocásticos
11.
J Theor Biol ; 238(2): 401-15, 2006 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-16045940

RESUMO

We present a mathematical analysis of the speciation model for food-web structure, which had in previous work been shown to yield a good description of empirical data of food-web topology. The degree distributions of the network are derived. Properties of the speciation model are compared to those of other models that successfully describe empirical data. It is argued that the speciation model unifies the underlying ideas of previous theories. In particular, it offers a mechanistic explanation for the success of the niche model of Williams and Martinez and the frequent observation of intervality in empirical food webs.


Assuntos
Evolução Biológica , Cadeia Alimentar , Modelos Estatísticos , Animais , Especiação Genética , Modelos Biológicos , Dinâmica Populacional , Comportamento Predatório
12.
Phys Rev Lett ; 95(1): 017201, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16090648

RESUMO

We show that suitably designed magnetic semiconductor heterostructures consisting of Mn delta (delta)-doped GaAs and p-type AlGaAs layers, in which the locally high concentration of magnetic moments of Mn atoms are controllably overlapped with the two-dimensional hole gas wave function, realized remarkably high ferromagnetic transition temperatures (T(C)). A significant reduction of compensative Mn interstitials by varying the growth sequence of the structures followed by low-temperature annealing led to high T(C) up to 250 K. The heterostructure with high T(C) exhibited peculiar anomalous Hall effect behavior, whose sign depends on temperature.

13.
Br J Ophthalmol ; 88(10): 1280-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15377551

RESUMO

BACKGROUND/AIMS: To determine outcomes of transplants of cultivated autologous oral epithelial cells in patients with severe ocular surface disorders. METHODS: The eyes (n = 6) of four patients with Stevens-Johnson syndrome (three eyes) or chemical burns (three eyes) were studied. Autologous oral epithelial cells, grown for 2-3 weeks on a denuded amniotic membrane carrier in the presence of 3T3 fibroblasts, were air lifted. The resultant sheet was transplanted onto the damaged eye, and acceptance of the sheet by the corneal surface was confirmed 48 hours after surgery. The success of ocular surface reconstruction, graft survival, changes in visual acuity, and postoperative complications were assessed and the quality of the cultivated oral epithelial sheet was evaluated histologically. RESULTS: At 48 hours after transplant, the entire corneal surface of all six eyes was free of epithelial defects indicating complete survival of the transplanted oral epithelium. Visual acuity was improved in all eyes. During follow up (mean 13.8 (SD 2.9) months), the corneal surface remained stable, although all eyes manifested mild peripheral neovascularisation. CONCLUSIONS: Autologous oral epithelial cells grown on denuded amniotic membrane can be transplanted to treat severe ocular surface disorders.


Assuntos
Doenças da Córnea/terapia , Células Epiteliais/transplante , Traumatismos Oculares/terapia , Mucosa Bucal/citologia , Adolescente , Adulto , Âmnio , Queimaduras Químicas/terapia , Células Cultivadas , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Síndrome de Stevens-Johnson/terapia , Resultado do Tratamento , Acuidade Visual
14.
Int J Radiat Biol ; 80(5): 339-45, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15223766

RESUMO

PURPOSE: Ophthalmologic examinations were conducted on atomic bomb (A-bomb) survivors 55 years after exposure. MATERIALS AND METHODS: A-bomb survivors who had been exposed before 13 years of age at the time of the bombings in 1945 or who had been examined in a previous study between 1978 and 1980. The examinations, conducted between June 2000 and September 2002, included slit-lamp examination, digital photography and a cataract grading system for three parts of the lens (nucleus, cortex and posterior subcapsule) as an outcome variable. Proportional odds logistic regression analysis was conducted using the lowest grading class as a reference and included explanatory variables such as age, sex, city, dose and various cataract-related risk factors. When the grades in an individual differed, the worst grade was used. RESULTS: Results indicate that odds ratios (ORs) at 1 Sv were 1.07 (95% confidence intervals [CI] 0.90, 1.27) in nuclear colour, 1.12 (95% CI 0.94, 1.30) in nuclear cataract, 1.29 (95% CI 1.12, 1.49) in cortical cataract and 1.41 (95% CI 1.21, 1.64) in posterior subcapsular cataract. The same was true after excluding 13 people whose posterior subcapsular cataracts had been previously detected. CONCLUSION: Significant radiation effects were observed in two types of cataracts in A-bomb survivors.


Assuntos
Catarata/epidemiologia , Guerra Nuclear/estatística & dados numéricos , Lesões por Radiação/epidemiologia , Medição de Risco/métodos , Sobreviventes/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Relação Dose-Resposta à Radiação , Feminino , Humanos , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Fatores de Risco , Índice de Gravidade de Doença , Distribuição por Sexo
15.
Eur J Ophthalmol ; 13(1): 1-10, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12635668

RESUMO

PURPOSE: To study the development of the rat lens vesicle in relation to apoptosis. MATERIALS AND METHODS: Fetuses of Wistar Kyoto rats were removed by laparotomy on day 10-15 of gestation. Some fetuses were fixed in 2% paraformaldehyde and embedded in paraffin for a TUNEL technique examination of DNA fragmentation. Macrophages were stained immunohistochemically with antibody. Some fetuses were fixed in 4% glutaraldehyde and 1% osmic acid and embedded in Luveak 812, then examined with a transmission electron microscope (TEM). RESULTS: On day 11 of gestation (E11) before the start of lens invagination, apoptotic changes were noted in the cells between the surface ectoderm and optic vesicle, with the appearance of phagocytic cells. Apoptotic cells were present at the junction of the surface ectoderm and the lens placode, in the ventral and dorsal thirds of the lens placode and in the outer layer of the optic vesicle in the same axes on E12. Apoptotic changes appeared in the lens stalk, surface ectoderm and the anterior lens epithelium on E12.5. The lens vesicle was detached completely from the surface ectoderm by E13 and some cells had the typical characteristics of macrophages in the extracellular space between the surface ectoderm and the anterior lens epithelium. Apoptotic changes were confirmed by the TUNEL method, and macrophages were stained immunohistochemically. CONCLUSIONS: Apoptosis may have a major role during the whole process of lens vesicle development. Apoptosis may eliminate the cells between the surface ectoderm and the optic vesicle, help trigger invagination and facilitate separation from the ectoderm. Apoptosis might aid in the bowing of the optic vesicle during lens invagination.


Assuntos
Apoptose/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Cristalino/embriologia , Animais , DNA/análise , Ectoderma/fisiologia , Ectoderma/ultraestrutura , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Cristalino/ultraestrutura , Macrófagos/citologia , Macrófagos/metabolismo , Microscopia Eletrônica , Morfogênese , Ratos , Ratos Endogâmicos WKY
16.
Eye (Lond) ; 16(2): 171-6, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11988818

RESUMO

PURPOSE: Side-effects after intravitreal use of silicone oil (SO) are not well defined and elucidated. The object of this study was to examine the influence and toxicity of SO on the optic nerve after vitrectomy with SO tamponade. METHODS: We injected medical grade SO and emulsified SO into rabbit eyes after gas-mediated vitreous compression and examined the eyes by light microscopy (LM), transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDXA) (point analysis and area analysis) 6 months after injection. We compared the findings in the non-treated eyes and eyes with only gas-mediated vitreous compression with those in SO-injected eyes. RESULTS: Vacuole-like structures were seen in the optic nerve posterior to the lamina cribrosa. In the group treated with only gas-mediated vitreous compression, the myelin structures were shown by TEM to be destroyed and replaced by glial tissue, while in groups injected with medical grade or emulsified SO severe destruction of the myelin sheath (myelinolysis) was observed. Silicone was identified at the electron-dense edges of the vacuoles by EDXA point analysis, but not in the vacuoles without electron-dense deposits. Dots of Si K alpha were not seen in the control groups, and dense dots were observed in SO-injected groups, by EDXA area analysis. CONCLUSIONS: Some of the vacuoles might be artefacts caused by insufficient fixation or the operative procedure, but TEM showed almost no artefacts in the control optic nerve. Thus, most vacuoles may be SO storage sites. SO uptake into the optic nerve might play a role in the pathogenesis of optic nerve atrophy after SO injection.


Assuntos
Doenças do Nervo Óptico/induzido quimicamente , Óleos de Silicone/toxicidade , Vitrectomia , Animais , Injeções , Microscopia Eletrônica , Nervo Óptico/ultraestrutura , Doenças do Nervo Óptico/patologia , Coelhos , Difração de Raios X/métodos
17.
Ital J Anat Embryol ; 106(2 Suppl 1): 237-44, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11729961

RESUMO

The purpose of the present study is to clarify the specific retinal vascular changes in rat models of single spontaneous or hereditary systemic diseases. We used Wistar Kyoto (WKy) rats 6 months of age as normal controls, 24-month-old Wistar Kyoto rats in studies of aging, 16-month-old spontaneously hypertensive rats (SHR), 18-month-old rats with inherited hypercholesterolemia (RICO) for arteriosclerosis, and 18-month-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats for diabetes mellitus. Retinal vascular corrosion casts were made and observed with a scanning electron microscope. The retinal vessels were also examined with a transmission electron microscope. Specific changes in the retinal vessels were: narrowing and thin thread-like capillaries in aging; capillary tortuosity, irregularity and narrowing in hypertension; straightening in hypercholesterolemia; and loop formation and microaneurysms in diabetes mellitus. These specific changes in the retinal vessels in each systemic disease can be clearly and easily revealed in a three-dimensional fashion by corrosion casts followed by scanning electron microscopy.


Assuntos
Retina/patologia , Doenças Retinianas/patologia , Vasos Retinianos/patologia , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Capilares/patologia , Capilares/fisiopatologia , Capilares/ultraestrutura , Molde por Corrosão , Complicações do Diabetes , Diabetes Mellitus/patologia , Diabetes Mellitus/fisiopatologia , Hipercolesterolemia/complicações , Hipercolesterolemia/patologia , Hipercolesterolemia/fisiopatologia , Hipertensão/complicações , Hipertensão/patologia , Hipertensão/fisiopatologia , Microscopia Eletrônica de Varredura , Ratos , Ratos Endogâmicos OLETF , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Retina/fisiopatologia , Retina/ultraestrutura , Artéria Retiniana/patologia , Artéria Retiniana/fisiopatologia , Artéria Retiniana/ultraestrutura , Doenças Retinianas/fisiopatologia , Veia Retiniana/patologia , Veia Retiniana/fisiopatologia , Veia Retiniana/ultraestrutura , Vasos Retinianos/fisiopatologia , Vasos Retinianos/ultraestrutura
18.
Ital J Anat Embryol ; 106(2 Suppl 1): 245-50, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11729962

RESUMO

No previous attempt has been made so to demonstrate the details of the choroid vascularization in the rat. This paper describes the choroidal vascular pattern of the normal Wistar Kyoto rat using the corrosion cast method. 6-month-old normal Wistar Kyoto rats were used. Vascular casts prepared by our previously described technique were observed with a Hitachi S-2360N scanning electron microscope. Corrosion casts of the entire choroidal vasculature showed that the ophthalmic artery branched into two main ciliary arteries: the nasal and temporal arteries, which extend forward to form the iridociliary circle. Further the inferior ciliary artery arises from the temporal ciliary artery. In the posterior eye segment these arteries form four to seven branches supplying the adjacent choriocapillaris. There are different arrangements of choriocapillaris. The larger veins formed four vortex veins, one in each quadrant, draining blood from the anterior region of the choroid or iris. Venous blood from the central region, peripapillary choroid and sometimes optic nerve head is drained by smaller veins, which run more or less directly into the posterior ciliary veins. In conclusion corrosion casts and SEM can show the details of the choroidal vascular architecture. These three-dimensional (3-D) findings of choroidal vessels of the rat are very useful for the study of choroid vascular abnormalities in various pathological conditions.


Assuntos
Corioide/irrigação sanguínea , Corioide/ultraestrutura , Microcirculação/ultraestrutura , Artéria Oftálmica/ultraestrutura , Veias/ultraestrutura , Animais , Corioide/fisiologia , Molde por Corrosão , Feminino , Masculino , Microcirculação/fisiologia , Microscopia Eletrônica de Varredura , Artéria Oftálmica/fisiologia , Ratos , Ratos Endogâmicos WKY , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Veias/fisiologia
19.
Phys Rev Lett ; 87(23): 238302, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11736480

RESUMO

Propagation of waves in an extended excitable system is considered. It is shown that traveling wave fronts can be triggered and maintained via local periodic modulations of an appropriate system parameter. For a finite range of perturbation frequencies, this new class of pacemakers introduces spatiotemporal self-organization in an otherwise quiescent medium. Excitation waves of activity similar to those observed in heart tissue cultures and other biological preparations can emerge in the presence of these pacemakers.


Assuntos
Relógios Biológicos , Modelos Teóricos , Coração/fisiologia , Modelos Biológicos
20.
J Glaucoma ; 10(5): 429-35, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11711844

RESUMO

PURPOSE: To examine surgical effects and complications of improved nonpenetrating trabeculectomy with trabeculotomy in glaucoma patients. METHODS: Glaucoma patients in two medical institutions underwent nonpenetrating trabeculectomy with sinusotomy with or without trabeculotomy, and the results were compared retrospectively in the two groups by evaluation of final intraocular pressure, drug score, and occurrence of postsurgical complications. RESULTS: Of the 63 eyes of 51 patients in this study, 31 were treated with nonpenetrating trabeculectomy with sinusotomy without trabeculotomy and 32 eyes were treated with nonpenetrating trabeculectomy with sinusotomy and trabeculotomy. The mean follow-up period was 17.0 months. The clinical features in both groups were similar in terms of age, presurgical intraocular pressure (P = 0.96), and presurgical drug score. The eyes treated with nonpenetrating trabeculectomy with sinusotomy without trabeculotomy had significantly reduced intraocular pressures from 21.0 +/- 4.3 (mean +/- SD) to 15.8 +/- 6.3 mm Hg (P = 0.0003) and drug scores from 2.4 +/- 1.2 to 1.6 +/- 1.1 without postsurgical complications. The eyes treated with nonpenetrating trabeculectomy with sinusotomy and trabeculotomy had significantly reduced intraocular pressures from 22.3 +/- 7.5 to 12.5 +/- 2.3 mm Hg (P < 0.0001) and drug scores from 2.5 +/- 1.9 to 0.9 +/- 1.3 without postsurgical complications. Thus, the eyes treated with nonpenetrating trabeculectomy with sinusotomy and trabeculotomy had significantly lower intraocular pressures (P = 0.016) and drug scores than did those treated with nonpenetrating trabeculectomy with sinusotomy without trabeculotomy. CONCLUSION: The authors obtained satisfactory results in reducing intraocular pressure by the combination of nonpenetrating trabeculectomy, sinusotomy, and trabeculotomy.


Assuntos
Glaucoma/cirurgia , Trabeculectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
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