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1.
Hum Reprod Update ; 27(1): 1-26, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33395479

RESUMO

There is emerging evidence that early uterine development in humans is an important determinant of conditions such as ontogenetic progesterone resistance, menstrual preconditioning, defective deep placentation and pre-eclampsia in young adolescents. A key observation is the relative infrequency of neonatal uterine bleeding and hormone withdrawal at birth. The origin of the uterus from the fusion of the two paramesonephric, or Müllerian, ducts was described almost 200 years ago. The uterus forms around the 10th week of foetal life. The uterine corpus and the cervix react differently to the circulating steroid hormones during pregnancy. Adult uterine proportions are not attained until after puberty. It is unclear if the endometrial microbiome and immune response-which are areas of growing interest in the adult-play a role in the early stages of uterine development. The aim is to review the phases of uterine development up until the onset of puberty in order to trace the origin of abnormal development and to assess current knowledge for features that may be linked to conditions encountered later in life. The narrative review incorporates literature searches of Medline, PubMed and Scopus using the broad terms individually and then in combination: uterus, development, anatomy, microscopy, embryology, foetus, (pre)-puberty, menarche, microbiome and immune cells. Identified articles were assessed manually for relevance, any linked articles and historical textbooks. We included some animal studies of molecular mechanisms. There are competing theories about the contributions of the Müllerian and Wolffian ducts to the developing uterus. Endometrium features are suggestive of an oestrogen effect at 16-20 weeks gestation. The discrepancy in the reported expression of oestrogen receptor is likely to be related to the higher sensitivity of more recent techniques. Primitive endometrial glands appear around 20 weeks. Features of progestogen action are expressed late in the third trimester. Interestingly, progesterone receptor expression is higher at mid-gestation than at birth when features of endometrial maturation are rare. Neonatal uterine bleeding occurs in around 5% of neonates. Myometrial differentiation progresses from the mesenchyme surrounding the endometrium at the level of the cervix. During infancy, the uterus and endometrium remain inactive. The beginning of uterine growth precedes the onset of puberty and continues for several years after menarche. Uterine anomalies may result from fusion defects or atresia of one or both Müllerian ducts. Organogenetic differentiation of Müllerian epithelium to form the endometrial and endocervical epithelium may be independent of circulating steroids. A number of genes have been identified that are involved in endometrial and myometrial differentiation although gene mutations have not been demonstrated to be common in cases of uterine malformation. The role, if any, of the microbiome in relation to uterine development remains speculative. Modern molecular techniques applied to rodent models have enhanced our understanding of uterine molecular mechanisms and their interactions. However, little is known about functional correlates or features with relevance to adult onset of uterine disease in humans. Prepubertal growth and development lends itself to non-invasive diagnostics such as ultrasound and MRI. Increased awareness of the occurrence of neonatal uterine bleeding and of the potential impact on adult onset disease may stimulate renewed research in this area.


Assuntos
Endométrio , Útero/crescimento & desenvolvimento , Adolescente , Animais , Feminino , Humanos , Menarca , Morfogênese , Gravidez , Hemorragia Uterina
2.
Taiwan J Obstet Gynecol ; 59(2): 314-317, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32127156

RESUMO

OBJECTIVE: Primary vaginal leiomyosarcomas (LMS) are rare, easily recurrent tumours with an unknown etiology; the prognosis is poor and there is no consensus guideline on their management. CASE REPORT: A nodular, 25 × 23 x 28 mm-mass, infiltrating the urethra, was found in a 58-year-old woman. A biopsy showed a LMS of the vagina that was positive for vimentin, alpha-smooth muscle actin, caldesmon, desmin, p16 and p53. An anterior pelvic exenteration was performed. The sample was fixed and prepared for light microscopy, transmission and scanning electron microscopy, confirming the diagnosis of LMS. CONCLUSIONS: Best outcomes occur when the tumour is small, localized, and can be removed surgically with wide, clear margins, as in this case. As there are different kinds of malignant mesenchymal tumours, biopsy followed by immunohistochemistry and electron microscopy still represents a good diagnostic choice and surgical resection is generally the gold standard in these cases.


Assuntos
Leiomiossarcoma/patologia , Neoplasias Vaginais/patologia , Biópsia , Feminino , Humanos , Imuno-Histoquímica , Leiomiossarcoma/ultraestrutura , Microscopia , Microscopia Eletrônica de Transmissão e Varredura , Pessoa de Meia-Idade , Prognóstico , Vagina/patologia , Neoplasias Vaginais/ultraestrutura
3.
Food Chem Toxicol ; 108(Pt A): 63-73, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28713048

RESUMO

Caralluma fimbriata Wall. is currently used as a "natural slimming" food supplement, likely due to its content in pregnane glycosides. In the present study, a commercially available Caralluma fimbriata extract (Slimaluma®; CFE, 100 mg/kg) has been evaluated for its ability to affect the ingestive behaviour in female rats, also with reference to the modulation of the brain neuropeptides NPY and ORX.The interference of CFE with α-amylase and lipase enzymes has been investigated in vitro, as possible peripheral mechanism of action. Also, the chemical composition of CFE has been assessed by NMR and spectrophotometric analysis. Results from in vivo study showed that CFE induced effects neither on blood parameters, nor on liver and gut histomorphology. Interestingly, a reduction in body weight gain with an increase in water intake and hypothalamic levels of NPY and ORX peptides were found. Phytochemical analysis, showed CFE contained about 12% of pregnane glycosides and 1.3% of polyphenols. Present results suggest possible effects of C. fimbriata on ingestive behaviour, likely mediated by central and peripheral mechanisms.


Assuntos
Apocynaceae/química , Depressores do Apetite/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Depressores do Apetite/química , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Compostos Fitoquímicos/química , Extratos Vegetais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
4.
Anat Sci Educ ; 6(5): 294-306, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23509097

RESUMO

Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and discussed during integrated second-year neuroanatomy, neuroradiology, and neurosurgery lectures over the 2008-2011 period. Anonymous questionnaires, evaluated according to the Likert scale, demonstrated that students appreciated this teaching procedure. Academic performance (examination grades for neuroanatomy) of the students who attended all integrated lectures of neuroanatomy, was slightly though significantly higher compared to that of students who attended these lectures only occasionally or not at all (P=0.04). Significantly better results were obtained during the national progress test (focusing on morphology) by students who attended the MRI/DTI-assisted lectures, compared to those who did so only in part or not at all, compared to the average student participating in the national test. These results were obtained by students attending the second, third and, in particular, the fourth year (P≤0.0001) courses during the three academic years mentioned earlier. This integrated neuroanatomy model can positively direct students in the direction of their future professional careers without any extra expense to the university. In conclusion, interactive learning tools, such as lectures integrated with intraoperative MRI/DTI images, motivate students to study and enhance their neuroanatomy education.


Assuntos
Imagem de Tensor de Difusão , Educação de Graduação em Medicina/métodos , Imageamento por Ressonância Magnética , Neuroanatomia/educação , Procedimentos Neurocirúrgicos/educação , Ensino/métodos , Estudos Transversais , Currículo , Avaliação Educacional , Escolaridade , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Neuronavegação/educação , Estudantes de Medicina , Inquéritos e Questionários , Universidades , Adulto Jovem
5.
Anticancer Res ; 33(3): 917-22, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23482762

RESUMO

AIM: Inadequate cervical sampling is the most frequent cause of misdiagnosis in cervical cancer screening. The aim of this study was to test the ability of PapCone® versus the conventional sampling method (Ayre's spatula plus cytobrush) to collect ectocervical and glandular cells. MATERIALS AND METHODS: In 18 healthy women, two ecto-endocervical samples, obtained by two different methods, were obtained at a three-month interval. Qualitative and quantitative parameters were evaluated. Ultrastructure features of sampling devices were analyzed by scanning electron microscopy (SEM) before and after sampling. RESULTS: The χ(2) test revealed a statistically significant difference between the two methods: PapCone® caused less cell overlap and sampled less white blood cells (p<0.05) and more metaplastic cells (p<0.01). SEM evaluation highlighted the porous and spongy structure of PapCone® that was responsible for the large number of glandular cells on its surface. CONCLUSION: Cervical smears performed by PapCone® were adequate and generally easier to screen than conventionally performed ones.


Assuntos
Esfregaço Vaginal/instrumentação , Adulto , Feminino , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Satisfação Pessoal , Estudos Prospectivos , Esfregaço Vaginal/métodos
6.
J Vasc Surg ; 53(6): 1649-53, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21609798

RESUMO

BACKGROUND: Extravasation of erythrocytes (erythrodiapedesis [ED]) is currently included among causes of skin damage in legs with chronic venous disorders (CVD) and ascribed to venular hypertension. ED is followed by erythrocyte disruption, degradation of hemoglobin, and storing of ferric iron into hemosiderin. The aim of this study was to evaluate the occurrence of ED in the skin of legs with different clinical stages of CVD. METHODS: One hundred eighteen skin biopsies from legs with CVD underwent histologic evaluation for ED and hemosiderin deposition (HD). RESULTS: ED was found in only 21/118 specimens. In particular, it was found in ulcer samples, in tissues surrounding varicophlebitis and, finally, in acute eczematous skin. ED was found in only 15/30 samples showing HD. CONCLUSION: Our findings confirm the occurrence of ED during CVD. However, it was found only in concomitance of severe dermal inflammation. Hemosiderin deposition in the absence of actual ED could be explained with previous healed episodes of skin inflammation. However, ED is not likely the only cause of skin iron overload, which could also occur by a molecular mechanism. Further studies are needed to define the mechanism of iron deposition in the skin of legs afflicted with CVD.


Assuntos
Eritrócitos/patologia , Pele/patologia , Insuficiência Venosa/patologia , Biópsia , Doença Crônica , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Pressão Venosa
7.
Surg Radiol Anat ; 30(8): 683-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18523715

RESUMO

Supernumerary ossicles (or Wormian bones) of the cranial vault are formations associated with insufficient rate of suture closure, and regarded as "epigenetic" and "hypostotic" traits. These bones rest along sutures and/or fill fontanelles of the neonatal skull. In this autoptic report of a 66-year-old Caucasian woman, a peculiar supernumerary bone is described, unusual size and shape, filling completely the bregmatic fontanelle. The skull was CT-scanned through coronal sections at 80 kV and 60 mA, with a slice thickness of 1.0 mm and a resolution of 0.35 mm/pixel. Segmentation and 3D rendering were computed using MIMICS 7.0 (digital endocast). The bone was pentagonal and remarkably large, more on the exocranial surface than on the endocranial one, involving both tables and diploe of the vault. This feature might represent a wedge to completion of the vault architecture. Considering the functional and structural matrix of cranial morphogenesis, this case displays the possibility of discrete diversification of the ossification centres, as well as the relative stability of the structural skull matrix in response to discrete changes.


Assuntos
Suturas Cranianas/anormalidades , Crânio/anormalidades , Idoso , Suturas Cranianas/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
8.
Front Biosci ; 13: 6730-51, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18508691

RESUMO

The zona pellucida (ZP) is a unique extracellular coat surrounding the maturing oocyte, during ovulation, fertilization, and early embryo development. It is formed by three/four glycoproteins. Ultrastructural data obtained with transmission (TEM) and scanning electron microscopy (SEM) were compared with molecular data on the glycoproteins network from ovulation to blastocyst formation. Molecular models are quite different to the morphology obtained with TEM, which shows a microfibrillar architecture, or with SEM, which shows a spongy or smooth surface. The saponin-ruthenium red-osmium tetroxide-thiocarbohydrazide technique allows to show the ZP real microfilamentous structure and the related functional changes. These results support an ultrastructural supramolecular model, more similar and comparable to molecular models related with the glycoprotein network. A detailed mapping of single mammalian ZP proteins and their relationship within the supramolecular architecture of the zona matrix would clearly supply insights into the molecular basis of sperm-egg recognition. Differences in ZP glycoproteins among mammals do not affect structural morphology; further studies are needed to clarify the relationships between ultrastructural and molecular organizations.


Assuntos
Desenvolvimento Embrionário/fisiologia , Fertilização/fisiologia , Zona Pelúcida/fisiologia , Animais , Feminino , Masculino , Mamíferos , Microscopia Eletrônica de Varredura , Oócitos/fisiologia , Oócitos/ultraestrutura , Ovulação , Interações Espermatozoide-Óvulo/fisiologia , Membrana Vitelina/fisiologia , Membrana Vitelina/ultraestrutura , Zona Pelúcida/ultraestrutura
9.
Arch Histol Cytol ; 70(1): 21-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17558141

RESUMO

In order to elucidate the ultrastructural dynamics of endometrium differentiation, uterine samples of fetuses aged 14 to 22 weeks of gestation (WG) were analyzed. Samples were processed for light (LM), transmission (TEM) and field-emission scanning electron microscopy (FE-SEM). Initial stratification of the uterine wall occurred at 14 WG: endometrial, myometrial, and perimetrial primordia were identified. At this age, the endometrial epithelium was simple columnar to pseudostratified and consisted of microvillous cells. Blood capillaries developed mainly in the stroma and between the myometrium and perimetrium primordia. At 18-20 WG the endometrial epithelium became clearly pseudostratified, with active ciliogenesis and a predominance of microvillous cells. Primordia of tubular glands were present at 20 WG. Microvillous cells still predominated in the endometrial epithelium at 21-22 WG and showed morphological features of apoptosis. The endometrial stroma at this stage was organizing into a thick lamina propria provided with subepithelial capillary plexuses. However, the stroma was formed by still undifferentiated mesenchymal cells during the whole period of study. Our data showed that the epithelial differentiation and distribution in the uterus occur in the human fetus in a similar way as in the adult. The above events are likely the expression of an early developmental patterning and related to future reproductive processes, such as the regulation of gamete passage and blastocyst implantation. Because the structure of the adult uterus is determined by the degree of paramesonephric duct fusion, septum absorption, and differentiation of the uterine primordial layers, our study may contribute toward clarifying to normal urogenital development.


Assuntos
Endométrio/embriologia , Endométrio/ultraestrutura , Idade Gestacional , Capilares/embriologia , Capilares/ultraestrutura , Diferenciação Celular , Cílios/fisiologia , Cílios/ultraestrutura , Endométrio/irrigação sanguínea , Endométrio/fisiologia , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Feminino , Humanos , Mesoderma/citologia , Mesoderma/ultraestrutura , Microvilosidades/ultraestrutura , Mucosa/embriologia , Mucosa/ultraestrutura , Gravidez , Segundo Trimestre da Gravidez
10.
J Vasc Surg ; 44(6): 1291-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17145433

RESUMO

BACKGROUND: Primary varicose veins are commonly considered a progressive disease starting from the saphenous junctions and extending to tributaries in a retrograde fashion along the saphenous trunks. This theory has been criticized by studies indicating different patterns of development and progression of varicose veins. To contribute to the understanding of the pathogenesis of the disease, the anatomy of the venous bed was comparatively evaluated by duplex sonography in patients with varicose veins with a marked difference in age. METHODS: The study included 100 varicose limbs in 82 patients aged < 30 years and 238 limbs in 183 patients aged > 60 years. Veins were designated as saphenous veins (SVs), tributaries of the SVs (STVs), and veins not connected with the SVs (NSVs). Four main anatomic patterns were comparatively evaluated: (1) varicose changes only along SVs, (2) varicose changes along SVs and STVs, (3) varicose changes only in STVs, and (4) varicose changes only in NSVs. RESULTS: SVs were normal in 44% of varicose limbs. In most limbs from young subjects, varicose changes afflicted only SVTs (25%) and NSVs (36%). Varicose SVs were more frequent in the older group (62%) than in younger one (39%) owing to a higher prevalence of limbs with combined SV and STV varicosities (respectively, 59% and 37%). In the older group, varicosities in the STVs were more frequently observed in association with incompetence of the SV trunks. CONCLUSION: The frequent occurrence of normal SVs in varicose limbs of all patients does not support the crucial role commonly credited to SVs in the pathogenesis of primary varicosities. Moreover, the SV trunks were normal in most varicose limbs from young patients. These findings suggest that varicose disease may progressively extend in an antegrade fashion, spreading from the STVs to the SVs. This hypothesis suggests that the saphenous trunks could be spared in the treatment of a relevant number of varicose legs. Prospective longitudinal studies with serial duplex evaluations of large series of extremities are necessary to confirm this hypothesis.


Assuntos
Envelhecimento/patologia , Veia Safena/patologia , Varizes/patologia , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Veia Safena/diagnóstico por imagem , Índice de Gravidade de Doença , Ultrassonografia Doppler em Cores , Varizes/diagnóstico por imagem , Varizes/epidemiologia , Grau de Desobstrução Vascular , Veias/patologia
11.
Microsc Res Tech ; 69(6): 415-26, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16703610

RESUMO

The mammalian zona pellucida (ZP) is an extracellular matrix surrounding oocytes and early embryos, which is critical for normal fertilization and preimplantation development. It is made up of three/four glycoproteins arranged in a delicate filamentous matrix. Scanning electron microscopy (SEM) studies have shown that ZP has a porous, net-like structure and/or nearly smooth and compact aspect. In this study, the fine 3-D structure of the human and mouse ZP is reviewed with the aim to integrate ultrastructural and molecular data, considering that the mouse is still used as a good model for human fertilization. By conventional SEM observations, numerous evidences support that the spongy ZP appearance well correlates with mature oocytes. When observed through more sophisticated techniques at high resolution SEM, ZP showed a delicate meshwork of thin interconnected filaments, in a regular alternating pattern of wide and tight meshes. In mature oocytes, the wide meshes correspond to "pores" of the "spongy" ZP, whereas the tight meshes correspond to the compact parts of the ZP surrounding the pores. In conclusion, the traditional "spongy" or "compact" appearance of the ZP at conventional SEM appears to be only the consequence of a prevalence of different arrangements of microfilament networks, according to the maturation stage of the oocyte, and in agreement with the modern supramolecular model of the ZP at the basis of egg-sperm recognition. Despite great differences in molecular characterization of ZP glycoproteins between human and mouse ZP, there are no differences in the 3-D organization of glycoproteic microfilaments in these species.


Assuntos
Ovulação/fisiologia , Zona Pelúcida/ultraestrutura , Animais , Proteínas do Ovo/química , Proteínas do Ovo/genética , Proteínas do Ovo/ultraestrutura , Feminino , Fertilização , Humanos , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura , Oócitos/ultraestrutura , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/ultraestrutura , Zona Pelúcida/fisiologia , Glicoproteínas da Zona Pelúcida
12.
Microsc Res Tech ; 69(6): 508-16, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16718668

RESUMO

The use of somatic cells for cocultures during in vitro fertilization (IVF) is currently finalized to obtain a higher number of healthy and viable embryos with a high potential of implantation. Among the different cell lines that can be used as feeder cells for cocultures, granulosa cells (GCs) are autologous cells, safe and easy to recover. The aim of the present study was to analyze the fine structure of human GCs used in a coculture system to evaluate, from a morphodynamic point of view, their role in supporting embryo development. GCs were collected during oocyte pick-up, 36 h after human chorionic gonadotropin administration, from patients undergoing IVF procedures, who had given their informed consent to be included in this protocol. After coculture, GCs were fixed and processed for light microscopy (LM) and transmission electron microscopy (TEM). By LM, GCs appeared as clusters of loosely packed cells, irregularly rounded or polyhedral in shape, varying in diameter from 18 to 25 microm. Mitotic cells, as well as regressing elements (with pyknotic nuclei or dense cytoplasm) and cell fragments were occasionally observed. By TEM, the plasma membrane was irregular due to the presence of cytoplasmic evaginations. Linear and annular gap junctions between neighboring GCs were found. GC nuclei, rounded and eccentrically located, contained finely dispersed chromatin, one (often two) prominent nucleoli and, infrequently, peripheral patches of heterochromatin. Numerous organelles populated the GC cytoplasm, among them, mitochondria were rod-shaped or elongated, usually provided with tubular-vesicular cristae but occasionally showing atypical, longitudinally oriented cristae. Membranes of smooth endoplasmic reticulum, Golgi stacks and vesicles, secretory-like granules, cisternae of rough endoplasmic reticulum (RER), free ribosomes and polysomes, lysosomal-like bodies, microfilaments, and lipid droplets were also seen in the GC cytoplasm. In most cells, RER was scarcely represented and numerous lipid droplets filled the perinuclear space. On the contrary, some GCs contained an abundant RER and rare lipid droplets scattered in the cytoplasm. In conclusion, our data demonstrated the presence, in a coculture system, of GCs provided with ultrastructural characteristics typical of healthy, metabolically active, mostly steroidogenic cells. Protein-synthetic cells have also been detected. These data, evaluated at the light of biochemical and clinical studies, sustain the capability of human GCs cocultures to positively affect early embryo development in vitro by the secretion of steroids and proteins, putative "embryotrophic" factors.


Assuntos
Fertilização in vitro/métodos , Células da Granulosa/ultraestrutura , Células Cultivadas , Técnicas de Cocultura , Embrião de Mamíferos/fisiologia , Feminino , Células da Granulosa/fisiologia , Humanos , Microscopia Eletrônica de Transmissão
13.
Int Rev Cytol ; 249: 53-141, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16697282

RESUMO

This study describes the updated, fine structure of human gametes, the human fertilization process, and human embryos, mainly derived from assisted reproductive technology (ART). As clearly shown, the ultrastructure of human reproduction is a peculiar multistep process, which differs in part from that of other mammalian models, having some unique features. Particular attention has been devoted to the (1) sperm ultrastructure, likely "Tygerberg (Kruger) strict morphology criteria"; (2) mature oocyte, in which the MII spindle is barrel shaped, anastral, and lacking centrioles; (3) three-dimensional microarchitecture of the zona pellucida with its unique supramolecular filamentous organization; (4) sperm-egg interactions with the peculiarity of the sperm centrosome that activates the egg and organizes the sperm aster and mitotic spindles of the embryo; and (5) presence of viable cumulus cells whose metabolic activity is closely related to egg and embryo behavior in in vitro as well as in vivo conditions, in a sort of extraovarian "microfollicular unit." Even if the ultrastructural morphodynamic features of human fertilization are well understood, our knowledge about in vivo fertilization is still very limited and the complex sequence of in vivo biological steps involved in human reproduction is only partially reproduced in current ART procedures.


Assuntos
Desenvolvimento Embrionário , Células Germinativas/fisiologia , Células Germinativas/ultraestrutura , Óvulo/ultraestrutura , Reprodução , Feminino , Fertilização , Células Germinativas/metabolismo , Humanos , Microscopia Eletrônica de Varredura , Ovulação , Gravidez , Técnicas Reprodutivas
14.
J Reprod Dev ; 51(4): 433-43, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15846046

RESUMO

In order to understand the 3-D distribution of collagen in relation to vascularization, chorionic villi of human placentae, belonging to normal pregnancies at term, were studied by scanning electron microscopy (SEM) after alkali maceration techniques, and by transmission electron microscopy (TEM). The villous tree appeared made of an uninterrupted structure of collagen fibres. The collagen fibres connected the chorionic villi axis with their basal plates and organised differently according to the various levels of villous branching. The collagen of stem villi showed copious fibres. The external fibres (facing the villous surface) were arranged mainly longitudinally. The central core of the villi (inner fibres) were arranged concentrically around the wall of the fetal vessels. Both external and internal fibres formed stratified lamellae or small parallel bundles. The inner core of stem villi showed small holes housing capillary spaces. Mature intermediate and terminal villi showed a scarce amount of collagen arranged in thin concentric layer within the villous core, surrounding numerous dilated capillary and sinusoid spaces.These observations demonstrated that the extracellular matrix of human chorionic villi is highly compartmentalised and shows a variable structural 3-D distribution depending on the branching level of the villous tree, such a distribution ensures the most favourable microenvironment for feto-maternal exchanges and it is likely able to provide a modulated support to the developing chorionic fetal vessels and trophoblastic layer as well.


Assuntos
Colágeno/biossíntese , Imageamento Tridimensional/métodos , Placenta/irrigação sanguínea , Placenta/ultraestrutura , Adulto , Vilosidades Coriônicas/metabolismo , Colágeno/química , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Feminino , Congelamento , Humanos , Troca Materno-Fetal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Neovascularização Patológica , Placenta/metabolismo , Gravidez , Hidróxido de Sódio/farmacologia , Trofoblastos/metabolismo
15.
Fertil Steril ; 78(2): 360-70, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12137875

RESUMO

OBJECTIVE: To evaluate the microanatomical dynamics of the ovary during postreproductive life. DESIGN: Retrospective, observational research study. SETTING: Institutional (university). PATIENT(S): Eleven (43- to 72-year-old) women in perimenopause, menopause, or postmenopause. INTERVENTION(S): Biopsies of ovaries obtained from patients undergoing gynecologic surgery or diagnostic procedures. MAIN OUTCOME MEASURE(S): Analysis of the 3-dimensional microanatomy of the ovary by transmission and high-resolution scanning electron microscopy. RESULT(S): The surface epithelium gets gradually flatter and is always present, even in advanced age. The surface appears smoother because of a smaller number of papillae and crypts as well as a decreased number and shortening of microvilli on surface epithelial cells. Signs of atrophy and fibrosis are evident. Primordial follicles are usually absent in postmenopause, whereas corpora atretica, hemorrhagica, and albicantia, scar tissue, and simple follicular cysts are common after menopause. Apoptotic and necrotic cells appear frequently within the surface epithelium. Major common features are a marked reduction in number and caliber of blood vessels with thickening of the vascular walls and changes in endothelial cells. CONCLUSION(S): Scanning electron microscopy studies are a useful complement to ordinary gynecologic diagnostic methods. Variations among patients of the same age range or functional status should be considered.


Assuntos
Ovário/ultraestrutura , Adulto , Idoso , Climatério , Matriz Extracelular/ultraestrutura , Feminino , Humanos , Menopausa , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Músculo Liso/ultraestrutura , Pós-Menopausa , Estudos Retrospectivos
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