A temporary disc-like structure at the median atlanto-axial joint in human fetuses / 대한해부학회지

Topographical anatomy of the greater omentum and transverse mesocolon: a study using human fetuses / 대한해부학회지

Ganglion cardiacum or juxtaductal body of human fetuses / 대한해부학회지

The ganglion cardiacum or juxtaductal body is situated along the left recurrent laryngeal nerve in the aortic window and is an extremely large component of the cardiac nerve plexus. This study was performed to describe the morphologies of the ganglion cardiacum or juxtaductal body in human fetuses and to compare characteristics with intracardiac ganglion. Ganglia were immunostained in specimens from five fetuses of gestational age 12–16 weeks and seven fetuses of gestational age 28–34 weeks. Many ganglion cells in the ganglia were positive for tyrosine hydroxylase (TH; sympathetic nerve marker) and chromogranin A, while a few neurons were positive for neuronal nitric oxide synthase (NOS; parasympathetic nerve marker) or calretinin. Another ganglion at the base of the ascending aorta carried almost the same neuronal populations, whereas a ganglion along the left common cardinal vein contained neurons positive for chromogranin A and NOS but no or few TH-positive neurons, suggesting a site-dependent difference in composite neurons. Mixtures of sympathetic and parasympathetic neurons within a single ganglion are consistent with the morphology of the cranial base and pelvic ganglia. Most of the intracardiac neurons are likely to have a non-adrenergic non-cholinergic phenotype, whereas fewer neurons have a dual cholinergic/noradrenergic phenotype. However, there was no evidence showing that chromogranin A- and/or calretinin-positive cardiac neurons corresponded to these specific phenotypes. The present study suggested that the ganglion cardiacum was composed of a mixture of sympathetic and parasympathetic neurons, which were characterized the site-dependent differences in and near the heart.

Is there a trans-abdominal testicular descent during the second gestational trimester? Study in human fetuses between 13 and 23 weeks post conception

ABSTRACT Objectives To confirm if a real inner descend of testis occurs, correlating the testicular position with fetal parameters and analyzing the position of the testes relative to the internal ring. Material and Methods Twenty nine human fetuses between 13 and 23 weeks post conception (WPC) were studied. The fetuses were carefully dissected with the aid of a stereoscopic lens with 16/25X magnification and testicular position observed. With the aid of a digital pachymeter the distance between the lower pole of the kidney and the upper extremity of the testis (DK-T) was measured to show the position of the testis. During the dissection we also indicated the position of the testes relative to the internal ring. Means were statistically compared using simple linear regression and the paired T-test. Results The 58 testes had abdominal position. The DK-T in the right side measured between 0.17 and 1.82cm (mean=0.79cm) and in the left side it was between 0.12 and 1.84cm (mean=0.87cm), without statistically differences (p=0.0557). The linear regression analysis indicated that DK-T in both sides correlated significantly and positively with fetal age. All fetuses with more than 20 WPC, heavier than 350g and with CRL over 22cm had a greater distance than the average DK-T. We xobserved that the 58 testis remains adjacent to the internal ring throughout the period studied. Conclusions The testes remains adjacent to the internal ring throughout the period studied, indicating that there is no real trans-abdominal testicular descent during the second gestational trimester.

Characterization of mesenchymal cells beneath cornification of the fetal epithelium and epidermis at the face: an immunohistochemical study using human fetal specimens / 대한해부학회지

Fetal development of the face involves a specific type of cornification in which keratinocytes provide a mass or plug to fill a cavity. The epithelial-mesenchymal interaction was likely to be different from that in the usual skin. We examined expression of intermediate filaments and other mesenchymal markers beneath cornification in the fetal face. Using sections from 5 mid-term human fetuses at 14–16 weeks, immunohistochemistry was conducted for cytokeratins (CK), vimentin, nestin, glial fibrilary acidic protein, desmin, CD34, CD68 and proliferating cell nuclear antigen (PCNA). Fetal zygomatic skin was composed of a thin stratum corneum and a stratum basale (CK5/6+, CK14+, and CK19+) and, as the intermediate layer, 2–3 layered large keratinocytes with nucleus. The basal layer was lined by mono-layered mesenchymal cells (CD34+ and nestin+). Some of basal cells were PCNA-positive. In the keratinocyte plug at the external ear and nose, most cell nuclei expressed PCNA, CK5/6, CK14, and CK19. Vimentin-positive mesenchymal cells migrated into the plug. The PCNA-positive nucleus as well as mesenchymal cell migration was not seen in the lip margin in spite of the thick keratinocyte layer. The lingual epithelium were characterized by the CK7-positive stratum corneum as well as the thick mesenchymal papilla. CD68-positive macrophages were absent in the epidermis/epithelium. Being different from usual cornification of the skin, loss of a mesenchymal monolayer as well as superficial migration of mesenchymal cells might connect with a specific differentiation of keratinocyte to provide a plug at the fetal nose and ear.

Estudo morfométrico do músculo latíssimo do dorso em fetos humanos / Morphometric study of the latissimus dorsi muscle in human fetuses

Introdução: O músculo latíssimo do dorso (MLD) é largo, triangular e realiza extensão, adução e rotação medial do braço. É vascularizado pelos vasos toracodorsais e ramos perfurantes das artérias intercostais posteriores e lombares, configurando retalho tipo V de Mathes e Nahai, de grande aplicabilidade em cirurgia plástica. O objetivo é analisar a morfometria e a vascularização do MLD em fetos humanos. Método: Dissecou-se a região axilar e o MLD de oito fetos humanos formolizados (três do sexo feminino e cinco do sexo masculino), entre 20 e 32 semanas gestacionais, em decúbito dorsal e abdução completa do braço. Mensuraram-se os comprimentos dos vasos subescapulares e toracodorsais, e foi realizada a morfometria do músculo. Resultados: Em todos os fetos, os vasos toracodorsais conferiram a vascularização primária do MLD. Em 25%, a veia subescapular era tributária direta da veia axilar; 25% dos casos apresentaram veia circunflexa da escápula dupla. O ramo para o músculo serrátil anterior foi único em todos os casos. Em 50% dos casos, o ramo angular da artéria toracodorsal foi visualizado e, em 25% deles, era proveniente do ramo para o músculo serrátil anterior. A distância entre a inserção do músculo e a entrada do pedículo neurovascular variou entre 1,1 e 1,9 cm em fetos de 21 e 26 semanas, respectivamente. Todos os fetos apresentaram a margem anterior do músculo na linha axilar média. Conclusão: A morfometria constante e a reduzida variação anatômica do pedículo vascular encontradas possibilitam a realização de pesquisas envolvendo o uso do MLD em reconstruções cirúrgicas intraútero.

Introduction: The latissimus dorsi muscle (LDM) is a flat triangular muscle which extends, adducts and draws the arm medially. Its blood supply is from the thoracodorsal vessels and the perforating branches of the posterior intercostal and lumbar arteries, therefore, it is a type V flap variety, which has great applicability in plastic surgery. This study aims to analyze the morphometry and the vascularization of MLD in human fetuses. Methods: The axillary region and LDM of eight human fetuses (3 females, 5 males), between 20 and 32 weeks of gestational ages, were dissected in supine position with complete abduction of the arm. The subscapular and thoracodorsal vessels lengths were measured and the morphology of the muscle was studied. Results: In all fetuses, the dominant vascular pedicle of LDM was the thoracodorsal vessels. In 25% of cases the subscapular vein was tributary of the axillary vein. Double circumflex scapular vein were found in 25% of the cases. In all fetuses, the serratus anterior branch was unique. In 50% of the cases the angular branch of the thoracodorsal artery was found, 25% of them were from the serratus anterior branch. The length between its insertion and the entry of the neurovascular pedicle was 1.1 to 1.9 cm in fetuses of 21 and 26 weeks, respectively. In all fetuses, the anterior border of the muscle was at the mid-axillary line. Conclusion: The constant morphometry and reduced anatomical variation of the vascular pedicle enables new studies regarding the use of LDM in surgical reconstructions in utero.

Initial stage of fetal development of the pharyngotympanic tube cartilage with special reference to muscle attachments to the tube / 대한해부학회지

Fetal development of the cartilage of the pharyngotympanic tube (PTT) is characterized by its late start. We examined semiserial histological sections of 20 human fetuses at 14-18 weeks of gestation. As controls, we also observed sections of 5 large fetuses at around 30 weeks. At and around 14 weeks, the tubal cartilage first appeared in the posterior side of the pharyngeal opening of the PTT. The levator veli palatini muscle used a mucosal fold containing the initial cartilage for its downward path to the palate. Moreover, the cartilage is a limited hard attachment for the muscle. Therefore, the PTT and its cartilage seemed to play a critical role in early development of levator veli muscle. In contrast, the cartilage developed so that it extended laterally, along a fascia-like structure that connected with the tensor tympani muscle. This muscle appeared to exert mechanical stress on the initial cartilage. The internal carotid artery was exposed to a loose tissue facing the tubal cartilage. In large fetuses, this loose tissue was occupied by an inferior extension of the temporal bone to cover the artery. This later-developing anterior wall of the carotid canal provided the final bony origin of the levator veli palatini muscle. The tubal cartilage seemed to determine the anterior and inferior margins of the canal. Consequently, the tubal cartilage development seemed to be accelerated by a surrounding muscle, and conversely, the cartilage was likely to determine the other muscular and bony structures.

A study on maturation of thyroid gland in human fetuses

The thyroid gland is the first endocrine gland to appear on the embryonic period. Its organogenesis beginswhen the medium endoderm cells start getting thick, forming a diverticulum, in the primitive pharynx floor.In this report, we describe the histological maturation of thyroid gland in human fetuses, correlating the tissueaspects with pregnancy stage. Twenty human fetuses were used in this study in different developmental stages.The fetuses from 20 to 36 weeks (gestational age) were dissected and the thyroid gland removed. The glandwas then embedded in paraffin, cut in frontal plans portions and stained with Hematoxylin and Eosin (H&E).We observed that the maturation process of the thyroid follicles was directly correlated with the gestationalage, where human fetus with 23 weeks of age did not show any sign of follicles or colloid and the one with35 weeks of age presented follicles with colloid. The conclusion of this study was that maturation process ofthe thyroid follicles tissue is a linear process with the fetal development.

Estudo estrutural do pênis de fetos humanos normais e anencéfalos no segundo trimestre de gestação / Structural study of the penis of normal and anencephalic human fetuses in the second trimester of pregnancy

A anecencefalia é o Defeito do Tubo Neural (DTN) mais severo em fetos humanos. Há uma demanda crescente para reposição tissular em doenças crônicas e cirurgias reconstrutoras. Tecidos fetais têm sido utilizados como substitutos para órgãos sólidos. Comparar a estrutura e morfologia do corpo cavernoso e corpo esponjoso de pênis de fetos humanos anencéfalos e de controle a fim de propor um novo modelo para estudos biológicos e transplantes teciduais. Foram estudados 11 pênis de fetos de controle de 14 a 23 Semanas Pós Concepção (SPC), e cinco pênis de fetos anencéfalos de 18 a 22 SPC. Os órgãos foram removidos e processados pelas técnicas histo e imunohistoquímicas rotineiras. A análise do tecido conjuntivo, células musculares lisas e fibras elásticas foram realizadas em lâminas dos espécimes. Os dados foram expressos em Densidade de àrea (Da) utilizando-se um software de processamento digital. As médias foram comparadas utilizando-se o Teste - T não pareado e quando aplicável, a regressão linear simples foi utilizada. Foi considerada significância estatística se p<0,05. O septo intercavernoso encontrava-se presente em todas as amostras. Não foram observadas diferenças da Da do tecido colágeno e musculatura lisa dos pênis de fetos anencéfalos quando comparados aos normais. A regressão linear simples sugere que durante o desenvolvimento humano há um aumen2to gradual do tecido colágeno (R2=0,45) e uma diminuição da musculatura lisa (R =0,62) no corpo cavernoso de ambos os grupos. A elastina encontrava-se presente apenas em fetos a partir da 20ª SPC. Não houve diferença na estrutura da genitália entre fetos normais e enencéfalos. Apresença da elastina em fetos a partir da 20ª SPC é um dado objetivo da manutenção da capacidade de ereção nestes grupos. A histo e imunohistoquímica sugerem que o desenvolvimento do pênis destes fetos encontra-se inalterado. Futuros estudos deverão ser realizados com o objetivo de avaliar fetos anencéfalos como um potencial ...

Anencephaly is the most severe neural tube defect (NTD) in human fetuses. There is an increasing need for tissue replacement in chronic diseases and reconstructive surgeries. Fetal tissues have been used as a substitute for native organs. Compare the structure and morphology of the corpora cavernosa and spongiosum of penises from anencephalic and normal human fetuses to propose a new model for biological studies and tissue transplantation. We studied 11 penises from normal human fetuses, aged 14 to 23 weeks post-conception (WPC), and 5 penises from anencephalic fetuses, aged 18 to 22 WPC. The organs were removed and processed by routine histological and immunolabeling techniques. Analysis of connective tissue (Cot), smooth muscle (SMC) and elastic fibers (EF) were performed in sections. Data were expressed as area density (Ad) using digital processing and software. Means were statistically compared using the unpaired t test and linear regression was performed. Statistical significance was considered if p < 0.05. The Intracavernosal septum was present in all samples. We did not observe differences in the Ad of Cot and SMC in the penises of anencephalic fetuses when compared to normal ones. The simple linear regression suggested that during human development there is a gradual increase in Cot (R2= +0.45) and a decrease of SMC (R2=- 0.62) in the corpora cavernosa in both groups studied. Elastin was observed only in fetuses from 20th WPC. There was no difference in the structure of the corpora cavernosa and corpus spongiosum of anencephalic fetuses compared to normal ones. Elastin was documented from 20th WPC, which suggests the maintenance of erectile function. Histochemistry and immunolabeling suggested that penile shaft development is maintained and unaltered in anencephalic fetuses. Further studies should be performed to analyze anencephalic fetuses as a potential tissue donating group and a model for biological studies

Ultrastructural Study on the Development of Ciliary Body in Human Fetuses

Morphological development of the ciliary body was studied by electron microscope in human fetuses from 50 to 260 mm crown-rump length(11-30 weeks of gestational age). At a 50 mm(11 weeks) fetus, the anlage of ciliary body was not appeared. At a 70 mm(13 weeks) fetus, the anlage of ciliary epithelium was appeared as the folds were formed by invaginating vessels in the basal surface of pigmented epithelium at the rim of optic cup. At the time, the anlage of ciliary muscle was formed as the mesenchymal cells, which located between the rim of optic cup and the scleral condensation, different-iate into the myoblasts, and the unmyelinated nerve fibers and the axon terminals were found in the interstitial tissue of mesenchyme. At 100-260 mm(15-30 weeks) fetuses, the myoblasts of ciliary body continued to develop into typical smooth muscle cells. At 200-260 mm(20-30 weeks) fetuses, the well-developed infoldings in the basal lamina and the well-developed interdigitations in the lateral sur-face were observed at both pigmented and nonpigmented epithelia. At the time, ganglion cells, Schwan cells and axon terminals were observed in the interstitial tissue of ciliary muscle.

Immunohistochemical and Electron Microscopic Study on the Esohageal Epithelium of the Human Fetus / 체질인류학회지

To clarify the developmental characteristics of fetal esophageal epithelium especially ciliated cell, expressions of epidermal growth factor receptor (EGFR) and cytokeratin (CK) in fetal esophageal mucosa (16-24 weeks of gestation) were studied immunohistochemically, and ultrastructure of the ciliated cells was also observed. The expressions of EGFR and CK were identified in labelled streptoavidine biotin immunohistochemical method. Primary antibodies used were EGFR (Ab-4) which is affinity-purified from hyperimmune rabbit sera (Oncogene Science) and monoclonal mouse anti-human cytokeratin (DAK0-CK, MNFl16). The esophageal lumen was lined with stratified ciliated columnar epithelium between 16 and 24 weeks of gestation. The pattern of expression Of EGFR was different with gestational age and epithelial layer. The ciliated cell exhibited variable staining intensity for EGFR at 16 weeks. Some were stained intensively, and others were stained faintly. Number of ciliated cells stained intensively were gradually increased, and most of them were strongly stained at 24 weeks. The superficial non-ciliated cells, however, showed relatively constant staining property of moderate to intense between 16 and 24 weeks. EGFR immunoreactivity was minimal in the basal and intermediate cells at 16 weeks, but became more intense at 24 weeks. CK immunoreactivity in the ciliated cells between 16 and 24 weeks was similar to that of EGFR immunoreactivity. On the other hand, superficial non-ciliated cells were intense for CK staining at 16 weeks, but were very weak to negative at 24 weeks. CK immunoreactivity was intense in basal and intermediate cells between 16 and 24 weeks, but it was almost negative in the some cells of intermediate layer, especially beneath negatively stained non-ciliated cells, at 24 weeks. In electron microscopy, ciliated cells had well organized cilia and dense granules close to Golgi apparatus between 16 and 24 weeks. The cells apparently active in ciliogenesis were also observed. These cells had short microvilli, many centrioles, and dense granules close to Golgi apparatus. The non-ciliated cells contained numerous clear vesicles adluminally clustered at 16 weeks, while they had many dense vesicles of about same size of clear vesicles at 24 weeks. These results demonstrate the expressions of EGFR and CK in esophageal epithelium of human fetus between 16 and 24 weeks of gestational ages, and suggest that the ciliated cells are still proliferative at 24 weeks.

Glycosaminoglycans in human fetal liver in relation to water and electrolytes.

The acidic mucopolysaccharides secreted into the extracellular space are thought to play many important functions amongst which are binding of water and electrolytes on the polyanionic glycosaminoglycans. Characteristically these components undergo continuous changes during growth and development of the fetuses. Relationships of the concentrations of glycosaminoglycans to the water and principal electrolytes at different periods of gestation were studied in human fetuses. It was found that during growth of the human fetuses there was a progressive decrease in water, thiocyanate space, total sodium content and glycosaminoglycans. However the decrease of glycosaminoglycans was greater than the rate of decrease of the other constituents. Hence mucopolysaccharides were thought to play more important roles than just binding of water and cations.

ULTRASTRUCTURAL STUDY OF THE PERITONEAL STOMATA IN HUMAN FETUSES / 解剖学报

In fifteen human fetuses spcimens the peritoneal stomata were studied with SEM and TEM, and measured by image processing system. In order to prove that the peritoneal stomata are the passageway of absorbed matter from the peritoneal cavity, animal experiments were made. There are two types of the mesothelial cells on diaphragmatic peritoneum, i. e. the cuboidal cells and the flattened cells. The peritoneal stomata, which arranged in clusters or strips, were only found between the cuboidal cells. The shape and size of the stomata were often irregular. The average area of the stoma on the muscular portion is 10.43?1.61?m~2, while on the tendinous portion is 7.93?1.67?m~2. The connective tissue underlies below the stomata, under which no basement membrane was found. Many lymphatic capillaries were observed in the connective tissue, which may promote absorption of matter from the peritoneal cavity. In animal experiments, some particles of trypan blue were absorbed through the stomata of rabbit diaphragmatic peritoneum. The authors consider that the stomata, are first observed in human, are important pathway for draining matter from the peritoneal cavity.

HISTOLOGICAL OBSERVATION ON ENDOCRINE CELLS IN HUMAN FETAL LUNGS / 解剖学报

Endocrine cells have been observed from 13 cases of human fetal lungs through the using of Grimelius silver staining technique, fluorescence microscopy and ultrastructural examinations. They were found in great number in the small bronchi than in any other part of bronchial tree. Most of them were round or oval in shape, and usually rest on the basement membrane of epithelium. They were stained by Grimelius silver stain. After incubation with L-Dopa they emitted a green glyoxylic acid-induced fluorescence. Typical feature of these cells was the numerous electron dense neurosecretory-type granules, 168-312 nm in diameter, which can be seen throughout the cytoplasm.

HISTOGENESIS OF THE HUMAN APPENDIX / 解剖学报

In this article 108 human fetuses from 12 to 30 weeks of gestation, 3 neonates and a 1.5 years child were used for study of the histogenesis of the appendix.In 12 weeks old fetus, the appendix showed small lumen and thin wall. The mucosa presented intestinal villi and crypts. The endocrine and goblet cells could be found. The circular muscle and serous membrane had differentiated. In the specimens of 13 to 15 weeks, the lamina propria contained diffused lymphatic tissue and lymphatic follicles. On such sites, the intestinal villi were absent. The surface epithelium became attenuate and composed of cuboid or lower cuboid cells. The outer longitudinal muscle layer was evident. The scattered muscularis mucosa was found. At 16 weeks, the endocrine cells appeared and showed various forms. The open-type or closed-type endocrine cells could be distinguished easily. Under EM, based on the morphology of the basal granules, the endocrine cells might be divided into two types. The granules were cell enclosed in a limiting membrane. One type of the granules was round and various in size, and another type was irregular. In the surface epithelium covered on the lymphatic tissue, the microfold cells could be found. They showed irregular microvilli or mierofolds and numerous apical micropinocytotic vesicles. At 18.5 weeks, the villi tended to merge each other. At 20 weeks, the muscularis mucosa was formed and the 4 layers of appendix resembled those of the normal adult. We found endocrine cells aggregated into Segi's cap on the apex of the villi in 7 fetuses of 16-21 weeks. The T or B lymphocytes could be identified as early as 13.5 weeks by immunologic method. We found the percentage of the B lymphocytes decreased with the gestation age, and this fact suggested that the appendix might be a B lymphocyte pool during the fetal period.

HISTOCHEMICAL AND ELECTRON MICROSCOPICAL OBSERVATION ON THYMIC NURSE CELL OF HUMAN FETUSES / 解剖学报

This paper reports some histochemical,scanning and transmission electron mic-roscopical features of thymic nurse cell(TNC)of human fetuses.The results showedthat TNCs were all negative for ANAE,AcP,AlP,ATPase,5'-Nase and PAS.TNCcontained various numbers of lymphocytes.Some intracytoplasmic lymphocytes werepositive for ANAE,AcP,AlP and ATPase.Their ANAE positive percentage deter-mined were 26.8%.However,ANAE positive percentage of extracytoplasmic lym-phocytes of TNC were 51.3%.Our data demonstrated that there was significant dif-ference between these two ANAE positive percentages,P

THE DEVELOPMENT OF THE CYTOARCHITECTURE OF THE HUMAN FETAL VISUAL CORTEX (AREA 17) PRIOR TO THE APPEARANCE OF SIX LAMINAE OF BRODMANN——A SCANNING ELECTRON MICROSCOPIC (SEM) OBSERVATION / 解剖学报

Tissue was obtained from 14 aborted human fetuses, ranging from 13-32 weeks of gestation (wg). The crown-rump length (CR) ranged from 8.3-33 cm. Frontal sections of the specimens were prosessed for SEM and observation were focused on the areas adjacent to the middle part of the calcarine fissure.At 13 wg (CR 8.3 cm), the visual cortex (area 17) was composed of five zones: viz., the ventricular zone, the subventricular zone, the intermediate zone, the cortical plate and the marginal zone. These five zones showed a series of transformations with increasing age. 1) The ventricular zone became progressively thinner, mitotic activity of the ventrieular cells decreased progressively and finally the ventricular ceils differentiated into a single layer of ependymal cells. 2) The subventricular zone and the inter mediated zone were replaced by fiber bundles of white matter. 3) The cortical plate increased in width, exhibited the greatest growth rate, and became differentiated. At 21 wg (CR 20cm), the lower part of the cortical plate first gave rise to laminae VI and V. At 23 wg (CR 22cm), lamina Ⅳ was established in the middle part of cortical plate. At 26 wg (CR 25cm), laminae Ⅲ and Ⅱ could be identified in the upper part of cortical plate. 4) The marginal zone transformed into lamina Ⅰ at its original site.