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1.
J Laryngol Otol ; 116(6): 420-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12385351

RESUMO

Surfaces of aural polyps collected from 30 patients were examined by scanning electron microscopy. In the polyps not associated with cholesteatoma, the epithelial lining showed individually variable metaplasia towards cuboidal 'cobblestone'-type and squamous epithelium covered with microvilli of various shapes and sizes. Squamous epithelium was present on the surface of all polyps with underlying cholesteatoma, with superficial cells possessing elongated microvilli, microplicae of different sizes, grooves and pits. Such surface structures reflect different stages of the keratinization process that seems to be characteristic for the epithelial lining of polyps with underlying cholesteatoma. Incomplete epithelium accompanied by granulation tissue was found in several polyps; in two cholesteatoma-associated polyps plate-like cholesterol crystals were observed.


Assuntos
Neoplasias da Orelha/ultraestrutura , Pólipos/ultraestrutura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/ultraestrutura , Criança , Orelha Externa/patologia , Orelha Média/patologia , Epitélio/patologia , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Microvilosidades/patologia , Pessoa de Meia-Idade
2.
Ital J Anat Embryol ; 106(2 Suppl 1): 221-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11729959

RESUMO

The vasculature of normal human urinary bladder wall and its tumors were studied using corrosion casting and scanning electron microscopy. In the normal wall, a regular organization of highly tortuous horizontal and vertical vessels allows accommodation of the vascular system to spatial changes resulting from the filling/voiding cycle. The vasculature of tumors is a result of remodeling of preexisting wall vessels associated with gradual growth of the neoplastic tissue. The shape and arrangement of blood vessels in different regions of the tumor seem to reflect a variable dynamics of tumor development and possible influence of various angiogenesis-promoting growth factors.


Assuntos
Vasos Sanguíneos/patologia , Vasos Sanguíneos/ultraestrutura , Diferenciação Celular/fisiologia , Molde por Corrosão/métodos , Neovascularização Patológica/patologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/ultraestrutura , Bexiga Urinária/irrigação sanguínea , Bexiga Urinária/ultraestrutura , Humanos , Masculino , Bexiga Urinária/patologia
3.
Ann Anat ; 183(4): 331-40, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11508358

RESUMO

The vascularization of the spinal cord was investigated in 50 human fetuses aged from 10 to 28 gestational weeks using dye injection methods and corrosion casting accompanied by scanning electron microscopy. In the investigated period of fetal development, the general vascular architecture of the spinal cord, corresponding to that described postnatally, seemed to be already established. The observed changes included: (1) remodeling of the supplying (extrinsic) arterial branches, (2) transformation of the posterior anastomotic chain into two distinct posterior spinal arteries, and (3) development of the capillary networks in the gray and white matter. The remodeling of the radicular arteries supplying the spinal cord was accompanied by a decrease in their number and transition from regular to irregular distribution (appearance of intersegmental differences in their frequency). The anterior spinal artery and regular array of the central arteries were already present in the youngest fetuses examined, but the final remodeling of the posterior anastomotic chain into two posterior spinal arteries occurred between 15th and 20th week of fetal life indicating that the vascularization of the anterior region of the spinal cord in the investigated period of fetal life was more advanced as compared with that of the posterior region. The capillary network of the gray matter in the youngest fetuses had the form of discrete glomerular plexuses supplied by groups of central arteries and mainly vascularizing the anterior horns. Successively, the plexuses fused to form a continuous system along the anterior columns and the system expanded to fully vascularize the posterior horns. The white matter in the earlier fetal period seemed to be partially avascular, later the density of capillaries vascularizing those areas was still much lower than in the gray matter. The veins showed considerably greater variability than the arteries, as far as their topography and distribution was concerned. High tortuosity characterized the superficial veins, especially in the younger fetuses, although the degree of tortuosity differed even between individual fetuses. Only anterior spinal and central arteries were usually accompanied by their venous counterparts, the other veins seemed to have no regular topographical relations with the arteries.


Assuntos
Artérias/embriologia , Medula Espinal/irrigação sanguínea , Medula Espinal/embriologia , Veias/embriologia , Aborto Espontâneo , Artérias/anatomia & histologia , Capilares/anatomia & histologia , Capilares/embriologia , Corantes , Molde por Corrosão , Embrião de Mamíferos/anatomia & histologia , Feminino , Feto/anatomia & histologia , Idade Gestacional , Humanos , Masculino , Gravidez , Veias/anatomia & histologia
4.
Med Sci Monit ; 7(3): 477-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11386029

RESUMO

The study material consisted of 18 patients (10 men, 8 women, aged 26-66 years), suffering from recurrent nasal polyps and bronchial asthma. Nine patients manifested intolerance to aspirin and non-steroid anti-inflammatory drugs (NSAIDs). The polyps removed during one of polypectomies were analysed with the help of scanning electron microscope (SEM) in order to evaluate the morphology of their surface. All the specimens displayed the increase in areas of cilium-free epithelium, covered with short microvilli and squamous epithelial cells. The arrangement of these changes was irregular and they were more pronounced in patients with intolerance to aspirin and NSAIDs. Apart from this, there were no other differences which would allow to differentiate in SEM investigation between polyps derived from patients with and without tolerance to NSAIDs.


Assuntos
Microscopia Eletrônica de Varredura/métodos , Adulto , Idoso , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Asma/patologia , Cílios/ultraestrutura , Células Epiteliais/ultraestrutura , Feminino , Humanos , Masculino , Microvilosidades/ultraestrutura , Pessoa de Meia-Idade , Pólipos Nasais/patologia
5.
Auris Nasus Larynx ; 28(2): 137-41, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11240321

RESUMO

OBJECTIVES: to compare morphological and clinical features of antrochoanal polyps and chronic inflammation-associated polyps of the maxillary sinus. STUDY DESIGN: histological and scanning electron microscopic examination of ten antrochoanal polyps and ten chronic inflammation-associated polyps of the maxillary sinus; comparison of clinical data in both groups of patients. METHODS: following surgical removal, the polyps were halved, the halves being processed for routine light microscopy (formalin fixation, paraffin embedding, HE staining) and scanning electron microscopy (formaldehyde/glutaraldehyde fixation, critical point drying, gold coating), respectively. Clinical data were retrospectively reviewed, tabulated and compared. RESULTS: the antrochoanal polyps differed from chronic inflammation-associated polyps of the maxillary sinus only in a few minor features; slightly longer duration of the process, lower incidence of maxillary ostial obstruction, higher incidence of frequent headaches, persistent nasal obstruction, presence of cysts in the polyp stroma, thickened basement membrane, lower incidence of squamous cell metaplasia, and higher proportion of migratory cells in nasal smears. In two cases, allergy was diagnosed but it seemed not to influence the polyps, which did not show morphological features typical of allergy-associated (eosinophilic) polyps. CONCLUSIONS: In spite of minor differences, antrochoanal polyps can be regarded as chronic inflammation-associated polyps with cystic origin and peculiar localization.


Assuntos
Pólipos Nasais/patologia , Pólipos Nasais/fisiopatologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Sinusite Maxilar/patologia , Sinusite Maxilar/fisiopatologia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Doenças dos Seios Paranasais/patologia , Doenças dos Seios Paranasais/fisiopatologia
6.
Przegl Lek ; 58(11): 975-8, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11987838

RESUMO

The study was performed in order to evaluate quantity and morphology of nasal polyps in patients with diagnosed drug allergy to aspirin, antibiotics, polocain, procain and other drugs. The study included 60 patients (27 females, 33 males aged between 18-69 years). Nasal polyp morphology was examined under electron microscope and light microscope. Morphological evaluation of epithelial and subepithelial structures was done under light microscope, taking not of inflammatory infiltration type, basal membrane, as well as degree of intestinal edema. Evaluation of epithelial cell type, their relative proportion, as well as area percentage covered by cilium, microvilli and squamous epithelium was done under electron microscope. Polyps in patients with idiosyncrasy to polish aspirin and sodium metamizole (12 patients) featured increased eosinophilic infiltration, thickened basal membrane, with elevated eosinophil percentage differential count. The epithelial percentage area was covered by squamous cells without villi. Polyps associated with idiosyncrasy to polish aspirin differed morphology compared to polyps originality from patients allergic to other medications. On the other hand polyps from patients allergic to other drugs, such as: penicillin, procainamide were morphologically (electron light microscope, light microscope) similar to those polyps caused by inflammatory factors.


Assuntos
Hipersensibilidade a Drogas/complicações , Mucosa Nasal/patologia , Pólipos Nasais/etiologia , Pólipos Nasais/patologia , Adulto , Idoso , Hipersensibilidade a Drogas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/diagnóstico por imagem , Pólipos Nasais/diagnóstico por imagem , Polônia/epidemiologia , Ultrassonografia
7.
J Laryngol Otol ; 114(5): 350-3, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10912263

RESUMO

Polyps of the maxillary sinus were obtained from six patients who had reported upper tooth extraction with oroantral perforation prior to the development of symptoms, from 11 patients with chronic sinusitis, and from 12 patients with allergy. Histopathological features, scanning electron microscopy of the polyp epithelium and clinical data were compared in those groups of patients. The post-traumatic polyps differed from those of other aetiologies by showing the presence of granulomas, less numerous inflammatory cells with very few eosinophils, nearly normal surface epithelium (smaller surface area occupied by nonciliated epithelium, absence of epithelial squamous cells, normal frequence of goblet cells), rapid appearance of symptoms, and shorter duration of the disease. It seems that the specific characteristics of the injury-induced polyps results from a different mechanism of their formation, involving primarily abnormal mucosal repair and to a lesser extent an inflammatory process.


Assuntos
Seio Maxilar , Pólipos Nasais/etiologia , Pólipos Nasais/patologia , Extração Dentária/efeitos adversos , Adolescente , Adulto , Idoso , Eosinófilos/metabolismo , Feminino , Humanos , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade
8.
Przegl Lek ; 57(12): 702-6, 2000.
Artigo em Polonês | MEDLINE | ID: mdl-11398590

RESUMO

The aim of the study was the microscopic evaluation of internal structure of cuprophane and polysulfone membrane and their surface analysis before and after reprocessing. The investigations were performed using an optical measurement system (Digital Instruments), a scanning electron microscope (SEM) and an atomic force microscope (AFM). We confirmed by SEM that reprocessing completely removed biofilm from both membranes surface. The analysis based on AFM visualized channels in the examined membrane. The diameter of the channels varied from 150 nm for cuprophane to 380 nm for polysulfone. The roughness expressed as root mean square (RMS) was higher for cuprophane than for polysulfone membrane. The physical differences between nanostrucure of the examined membranes might be responsible for lower biocompatibility of cuprophane.


Assuntos
Materiais Biocompatíveis , Celulose/análise , Teste de Materiais/métodos , Membranas Artificiais , Microscopia Eletrônica de Varredura/métodos , Polímeros/análise , Diálise Renal/instrumentação , Sulfonas/análise , Celulose/análogos & derivados , Propriedades de Superfície
9.
Ann Anat ; 181(4): 353-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10427372

RESUMO

Vascular architecture of the gastric corpus was investigated in 16-24 wk human fetuses using a corrosion casting technique and the scanning electron microscopy. The general distribution of blood vessels seen in adults has already been established in the fetus, with three major vascular plexuses located in the serosa, submucosa and mucosa. The serosal plexus, supplied and drained by large extramural vessels, contained anastomosing, arcade-like arrays of arteries and veins with their branches piercing the muscularis and communicating with the compact submucosal plexus. Vertical arterioles and capillaries were sent by submucosal arteries to supply a very dense capillary plexus which surrounded the gastric pits and consisted of wide, sinusoidal vessels showing morphological manifestations of angiogenesis by intussusceptive growth. The plexus was drained by vertical venules emptying into submucosal veins. In contrast to the richly vascularized upper half of the mucosa, the lower half showed a relative paucity of blood vessels, probably due to the thinness of the fetal mucosa allowing an effective diffusion of oxygen and nutrients from the upper half. Neither arteriovenous anastomoses, nor end-arteries were found in the fetal stomach. Results of this study support one of the two existing models of mucosal vascularization in the human stomach: i.e. the model postulating the presence of short and long arterioles and two distinct, albeit interconnected capillary networks in the upper and lower zones of the mucosa respectively. In human fetuses, the latter network is absent; it probably develops by remodelling of the preexisting vertical capillaries in the last phase of pregnancy, prior to the onset of gastric gland function.


Assuntos
Vasos Sanguíneos/embriologia , Estômago/irrigação sanguínea , Estômago/embriologia , Adulto , Vasos Sanguíneos/anatomia & histologia , Vasos Sanguíneos/ultraestrutura , Feminino , Feto , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Eletrônica de Varredura , Modelos Estruturais , Gravidez
10.
Ann Anat ; 180(1): 73-7, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9488909

RESUMO

Dinosaur bones, 80 million years old, were studied in the scanning electron microscope, and subjected to X-ray microanalysis. Samples for the investigations were prepared according to specially elaborated, and simultaneously described methods. Analysed were (a) the morphological structure of the blood vessels and (b) the remains of their contents. The walls of the blood vessels were found to be morphologically identical with those in present-day reptiles. Bodies were found at several places inside the vessels which strongly remind one of erythrocytes in modern bones. X-ray microanalysis of places where these bodies were accumulated revealed much higher levels of iron, than at any other regions of the blood-vessel wall. Further analysis of the "dinosaur erythrocyte" iron content could be a starting point for the possible determination of oxygen in the earth's atmosphere, 80 million years ago.


Assuntos
Vasos Sanguíneos/ultraestrutura , Osso e Ossos/irrigação sanguínea , Eritrócitos/ultraestrutura , Fósseis , Répteis/anatomia & histologia , Animais , Osso e Ossos/química , Calcificação Fisiológica , Microanálise por Sonda Eletrônica , Eritrócitos/química , Fêmur/irrigação sanguínea , Microscopia Eletrônica de Varredura , Oligoelementos/análise
11.
Folia Morphol (Warsz) ; 56(4): 223-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9635355

RESUMO

The vascular pattern of the injected with Mercox human fetal larynges, especially of the anterior commissure and surrounding it area, was analysed within the horizontal and frontal sections under a light microscope. The main result of our study was confirmation of existence of the avascular "plane zero" situated above the anterior commissure, which separates that structure from the supraglottic tier. That finding i.e. avascular separation between teh middle and upper laryngeal compartments, already present in the fetal period, has clinical implications as far as the spread of neoplastic process within the larynx is cancerued.


Assuntos
Neoplasias Laríngeas/patologia , Laringe/irrigação sanguínea , Estudos de Casos e Controles , Humanos , Laringe/embriologia , Microcirculação/fisiologia
12.
Ann Anat ; 178(3): 215-22, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8712368

RESUMO

The vascular architecture of adrenal glands was investigated in human fetuses aged from 16 to 24 weeks, using microcorrosion casts and scanning electron microscopy. The fetal adrenals showed an arrangement of blood vessels remarkably similar to that described in adult glands. There was a clear centripetal pattern from superficial arteries and their branches, via irregular capillaries of the subcapsular plexus and definitive cortex, and then via the radial sinusoids and venous sinuses of the fetal cortex, to the central vein. Rare medullary arterioles traversed the cortex to break up into small local capillary networks in the central region of the gland. Some superficial capillaries were drained by occasional subcapsular veins. No portal system was observed in the fetal adrenals.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Capilares/ultraestrutura , Desenvolvimento Embrionário e Fetal , Glândulas Suprarrenais/embriologia , Glândulas Suprarrenais/ultraestrutura , Adulto , Artérias/embriologia , Artérias/ultraestrutura , Arteríolas/embriologia , Arteríolas/ultraestrutura , Capilares/embriologia , Feminino , Feto , Idade Gestacional , Humanos , Masculino , Microscopia Eletrônica de Varredura , Modelos Estruturais , Gravidez , Veias/embriologia , Veias/ultraestrutura
13.
Folia Morphol (Warsz) ; 55(3): 143-50, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9078673

RESUMO

The presented study was carried out on the fetal specimens of the eye-ball, together with the retrobulbar part of the optic nerve which were obtained from 15 human fetuses aged 16-20 weeks of the intrauterine life. The vascular casts were prepared by injection of low-viscosity resin Mercox which afterwards were analyzed in a scanning electron microscope (SEM). The technique employed allowed the authors to describe both the vascular pattern of the optic nerve as well as the network of arterial vessels which formed the Zinn and Haller's circle. The own original findings are compared with results obtained by other authors on the vasculature of the optic nerve in mammals and humans in different periods of the life.


Assuntos
Nervo Óptico/irrigação sanguínea , Nervo Óptico/ultraestrutura , Molde por Corrosão , Feto/irrigação sanguínea , Feto/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura
14.
Ann Anat ; 177(4): 361-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7625608

RESUMO

The vasculature of the dorsal mucosa of the tongue was investigated in 18-21 week human fetuses by corrosion casting and scanning electron microscopy. Microvascular systems of the fungiform, foliate and circumvallate papillae, albeit less complex, showed similarity to those described in children, while the capillary networks of the filiform papillae were not yet fully developed, having either a knot-like or cone-like form instead of the corolla-like pattern typical of the postnatal period. Morphological features suggesting angiogenesis included both capillary outgrowths characteristic of vascular sprouting and tiny holes in the vascular walls regarded as evidence of intussusceptive capillary growth. The subpapillary vascular network supplying and draining the papillary vessels was composed of the more superficial capillary bed and the deeper plexus of larger arterioles and venules.


Assuntos
Microcirculação/anatomia & histologia , Mucosa Bucal/irrigação sanguínea , Língua/irrigação sanguínea , Aborto Espontâneo , Feminino , Feto , Idade Gestacional , Humanos , Microcirculação/embriologia , Microcirculação/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Modelos Anatômicos , Mucosa Bucal/embriologia , Gravidez , Língua/embriologia
15.
Folia Morphol (Warsz) ; 54(3): 159-64, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8754474

RESUMO

In the light of already known differences on the vascular patterns between slow and fast contracing skeletal and extra-ocular muscles (EOM) which has been described in both mammals and man we were interested to see if same of these features are presented in the human EOM during the second half of the gestation. Therefore the microvasculature bed of EOM was studied by SEM of vascular corrosion casting technique. 15 human embryos at 16-20 week of gestation, after spontaneous abortion, were used for this study. The vasculature bed of the all EOM studied is composed of two layers i.e. the orbital and the global. The orbital layer, in all specimens examined, has shown a relatively higher number of transverse anastomoses than the global one, although the capillary vessels were arranged similarly on the both sides.


Assuntos
Feto/irrigação sanguínea , Músculos Oculomotores/irrigação sanguínea , Artéria Oftálmica/anatomia & histologia , Molde por Corrosão , Feto/anatomia & histologia , Humanos , Microcirculação/embriologia , Músculos Oculomotores/embriologia , Artéria Oftálmica/embriologia
16.
Przegl Lek ; 52(10): 504-8, 1995.
Artigo em Polonês | MEDLINE | ID: mdl-8834842

RESUMO

The research has been conducted on the material of 170 larynx thyroid cartilages of persons in the age range from 19 to 99 years, applying the radiological method, spectroscopy, electyronic scanning microskopy and rentgenological diffractometry. The distribution of certain elements has been determined in fragments of thyroid cartilage with different progression of mineralization. It has been proved that the elemental composition of the examined thyroid cartilages depends on the individual age and the progression of mineralization, resulting from the age.


Assuntos
Envelhecimento/fisiologia , Metais/análise , Minerais/análise , Osteogênese/fisiologia , Cartilagem Tireóidea/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Cartilagem Tireóidea/ultraestrutura
17.
Hum Reprod ; 9(10): 1958-63, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7844234

RESUMO

Vascular architecture was investigated, in 18-21 week old human fetuses, for the first time with the use of corrosion casting and scanning electron microscopy, which offer high resolution and three-dimensional images of the vascular networks. The general arrangement of large vessels was similar to that described for the mature oviduct; however, the intramural vasculature of the muscular layer and mucosal folds consisted predominantly of capillary and sinusoidal networks. A characteristic feature of the fetal oviduct was a prominent sub-serosal venous plexus, which was most extensive in the isthmic segment. The relatively low degree of differentiation found in the fetal oviduct vasculature seems to reflect its functional immaturity.


Assuntos
Molde por Corrosão , Tubas Uterinas/irrigação sanguínea , Tubas Uterinas/embriologia , Idade Gestacional , Microscopia Eletrônica de Varredura , Artérias/anatomia & histologia , Artérias/embriologia , Capilares/anatomia & histologia , Capilares/embriologia , Feminino , Humanos , Mucosa/irrigação sanguínea , Mucosa/embriologia , Músculo Liso/irrigação sanguínea , Músculo Liso/embriologia , Veias/anatomia & histologia , Veias/embriologia
18.
Eur Respir J ; 7(9): 1669-72, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7995398

RESUMO

The aim of this study was to examine the tracheal vasculature in 5 month human foetuses, and to determine whether it differs from that previously described by other authors for adult human trachea. The vascular bed was visualized using the technique of corrosion casting and examined by scanning electron microscopy. The arrangement of larger vessels: longitudinal tracheo-oesophageal arteries and veins, as well as their segmental branches running circumferentially in the intercartilaginous spaces, was similar to that observed in the trachea of adults. However, no blood sinuses reported to occur in the submucous venular plexus of the human trachea could be found in the foetuses. It is postulated that the possible functions of such sinuses acting as the capacitance system are related to the functional respiratory tract; hence, this vascular specialization is not yet developed in the foetus.


Assuntos
Traqueia/irrigação sanguínea , Vasos Sanguíneos/embriologia , Molde por Corrosão , Feto/anatomia & histologia , Humanos , Microscopia Eletrônica de Varredura , Traqueia/embriologia
19.
Eur J Morphol ; 32(1): 3-10, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8086266

RESUMO

The microcirculation of tooth buds at the bell stage obtained from 5-month-old human fetuses was studied using corrosion casting and scanning electron microscopy. Each tooth bud has two independent vascular networks: one of the enamel organ and one of the dental papilla. Both systems are supplied by vertical branches of the inferior alveolar artery. The vascular bed of the enamel organ consists of capillaries relatively uniform in shape, forming a moderately dense network with irregular meshes. In contrast, the vasculature of dental papilla is extremely dense and its vessels show a sinusoidal character and signs of a vivid angiogenesis. The cast surfaces of capillaries in both vascular systems show the presence of tiny blebs probably representing extravasations of the casting medium through endothelial fenestrations.


Assuntos
Germe de Dente/embriologia , Molde por Corrosão , Papila Dentária/irrigação sanguínea , Papila Dentária/embriologia , Órgão do Esmalte/irrigação sanguínea , Órgão do Esmalte/embriologia , Humanos , Microcirculação , Microscopia Eletrônica , Germe de Dente/irrigação sanguínea
20.
Arch Ophthalmol ; 111(11): 1573-7, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8240116

RESUMO

OBJECTIVE: Microscopic investigation of the hyaloid vascular system in 5-month-old human fetuses. METHODS: Corrosion casting and light and scanning electron microscopy. RESULTS: The hyaloid artery ramifies into a tuft of vasa hyaloidea propria, which communicates with the posterior portion of the tunica vasculosa lentis, characterized by a network of anastomosing vessels. They further pass to the lateral portion of the tunica, acquiring a nonanastomosing palisadelike array and drain into the vessels of the ciliary processes or, after bending over the edge of the developing iris, drain into the outer choriocapillaris. The tunica vasculosa lentis vessels also communicate with the pupillary membrane, a system of vascular arcades arranged in several interconnected tiers, supplied by the terminal branches of the long posterior ciliary arteries. In tunica vasculosa lentis, arterioles seem to pass directly into veins, without forming a capillary bed. CONCLUSIONS: At the investigated developmental stage, the fully developed hyaloid system enters its subsequent involution, and the vessels nourishing the vitreous have already involuted. The system is generally similar to that observed in other mammals.


Assuntos
Olho/irrigação sanguínea , Olho/ultraestrutura , Artérias/embriologia , Artérias/ultraestrutura , Molde por Corrosão , Olho/embriologia , Feminino , Feto/anatomia & histologia , Idade Gestacional , Humanos , Cristalino/irrigação sanguínea , Cristalino/embriologia , Cristalino/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Corpo Vítreo/irrigação sanguínea , Corpo Vítreo/embriologia , Corpo Vítreo/ultraestrutura
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