人胚胎发育中胰腺细胞的增殖变化

目的：探索人胚胎发育过程中胰腺细胞增殖水平。方法：应用免疫组织化学EnVision法，检测30例人胚胎胰腺组织PCNA的表达。结果：各胎龄段胰腺外分泌细胞PCNA的阳性表达均显著高于内分泌细胞，胚胎发育早期阶段(9-14w)外分泌细胞PCNA的阳性表达明显高于其它胎龄，胚胎发育晚期阶段(29-37w)内分泌部PCNA阳性率高于其它胎龄组。结论：在胚胎发育过程中胰腺外分泌部细胞增殖水平高于内分泌部，随着胎龄的变化，胰腺内、外分泌细胞的增殖水平也发生了变化。     

亮氨酸-脑啡肽样成分在人胎儿和新生儿脊髓的分布及在发育过程中的变化——免疫组织化学研究

用PAP和ABC法,观察了亮氨酸-脑啡肽(L-ENK)样免疫反应成分在52例胎龄为8-39周的人胎儿和2例新生儿脊髓的分布状况,并通过显微分光光度计对分布密度进行了量的变化的分析。L-ENK样阳性细胞在后角浅层始现于第16周胎儿,以后细胞数量随胎龄增长而逐渐增多,至第6个月达到高峰,此后却随胎龄增长而渐减,至降生前后已降至很少,即在胚胎发育过程中显示着“少—多—少”的变化规律。Ⅳ-Ⅶ层L-ENK样细胞出现略早(第14周),但数量很少且变化甚微,至第7个月以后,仅偶见散在的L-ENK样阳性细胞。L-ENK样阳性纤维和终末在后角浅层也始见于第16周胎儿,随胎龄增长而持续增多,至降生前后达到密和极密的程度。Ⅵ层内侧部(骶髓为后连合核)、Ⅶ层、网状核及其桕邻的侧索白质,L-ENK样纤维和终末从第14周开始出现,直至降生前后一直保持中等至密布的分布状态。     

P物质样、亮氨酸-脑啡肽样及5-羟色胺样免疫反应成分在人胎儿及新生儿Gudden被盖背核的分布及在发育过程中的变化——免疫组织化学技术研究

应用免疫组织化学方法,研究了P物质(SP样)、亮氨酸-脑啡肽(L-Enk)样及5-羟色胺(5-HT)样免疫反应成分在人胎儿(胎龄11.5周至35周)及新生儿(生后2天)脑干Gudden被盖背核的分布及发育过程中的变化。结果发现,SP样、L-Enk样及5-HT样免疫反应成分在Gudden被盖背核内最早出现的时间不同,SP样成分出现最早,SP样免疫反应纤维及终末分布非常密集,且主要分布在核中段的中心部;L-Enk样免疫反应胞体、纤维及终末主要分布在核的周围部,纤维及终末的密度中等,L-Enk样免疫反应细胞量较少;5-HT样免疫反应细胞主要分布在核周围部的内侧区,细胞数量中等。随胎龄的增长,SP样、L-Enk样及5-HT样免疫反应成分在Gudden被盖背核内的分布显示出不同的变化规律。     

Bcl-2在人胎肠系膜淋巴结发育中的表达

目的探讨Bcl-2免疫反应阳性细胞在肠系膜淋巴结组织发生过程中的分布及表达情况。方法收集因故终止妊娠人胎回肠33例,采用免疫组织化学SABC法染色显示Bcl-2免疫反应阳性细胞,用BioMiaspro图像分析软件对免疫反应阳性细胞进行计数,有关数据做统计学分析。结果9周胎龄人胎肠系膜淋巴结原基内开始出现极少的免疫反应阳性细胞,随胎龄的增长Bcl-2免疫反应阳性细胞数量随淋巴细胞数量增加而增加,尤以21~28周数量最多（P〈0.05）。Bcl-2阳性细胞早期散在分布,21周以后逐渐在淋巴小结聚集成团,在副皮质区呈集落样分布。随胎龄增长,Bcl-2免疫反应阳性强度略增加,13~20周Bcl-2免疫反应阳性强度最强（P〈0.05）。结论Bcl-2在人胎肠系膜淋巴结的组织发生过程中起重要的调节作用。     

CD20阳性反应细胞在人胎回肠的发育

目的探讨CD20免疫反应阳性细胞在人胎回肠的分布、定位及发育。方法收集因故终止妊娠人胎回肠30例,采用形态学及免疫组织化学S-P法染色显示CD20免疫反应阳性B细胞,用BioMias29图像分析系统对免疫反应阳性细胞进行计数,有关数据作统计学分析。结果12周胎龄,回肠壁问充质内出现CD20阳性反应细胞,单个散在分布,数量少。14周胎龄,可见CD20阳性反应细胞染色深,反应增强。16周胎龄,CD20阳性细胞散在或成群分布于绒毛中轴或深部结缔组织内。18周胎龄,CD20阳性反应细胞聚集形成淋巴小结。24周后,CD20阳性反应细胞数量明显增多,大量细胞参与构成集合淋巴小结。结论人胎回肠B淋巴细胞发育过程中,12周开始表达CD20分子。随胎龄增加,CD20阳性反应细胞数量逐渐增多,参与构成淋巴小结。     

突触体素、S—100蛋白和神经特异性烯醇化酶免疫反应神经纤维在人免疫器官的分布

目的：探讨人免疫器官突触体素、S－100蛋白和神经特异性烯醇化酶（NSE）免疫反应神经纤维的支配和免疫反应细胞的分布，为神经内分泌和免疫系统相互作用提供形态学资料。方法：应用免疫组织化学ABC法观察正常免疫器官包括胸腺、脾脏、淋巴结各30例。10％ 福尔马林固定，石蜡包埋。结果：胸腺，突触体素、S－100蛋白和NSE免疫反应神经众胸腺被膜随小叶间隔和血管胸腺皮质，再延伸到髓质形成神经纤维网，在胸腺组织散在分布突触体素、S－100蛋白和NSE免疫反应细胞。淋巴结，免疫反应神经纤维沿被膜和门部结缔组织小梁及血管进入皮质后主要分布于副皮质区环绕淋巴滤泡，进一步分支到达髓质。在髓质髓窦内有NSE免疫反应细胞。脾脏，免疫反应神经纤维沿着血管的各级分支进入脾实质，主要沿着脾动脉的分支而分布在白髓、红髓和边缘区，穿插于淋巴细胞之间。结论：在人免疫器官可能在神经内分泌免疫相互作用和调控。     

生长抑素样神经元及其纤维在人胎下丘脑的分布与发育研究

本文用免疫细胞化学技术观察了人胎下丘脑内含生长抑素样神经元及其纤维的分布与发育。胎龄14周,见浅染的生长抑素免疫反应阳性神经元散布于下丘脑前部、室周带、第三脑室壁室管膜上皮深面。15～16周胎龄,含生长抑素样神经元除见于上述部位外,还见于腹内侧基底部、室旁核、视上核和室管膜上皮内,阳性纤维散布于正中隆起,室管膜上皮。17—18周胎龄,含生长抑素样结构在上述部位变化明显,神经元更加密集,分布范围扩大,反应染色加深,阳性突起延长。21周胎龄至足月胎儿,含生长抑素神经元及其纤维在下丘脑的分布变化不明显。生长抑素样神经元以中、小型细胞为主,室旁核内见有少量大细胞。电镜观察21周和29周胎龄正中隆起发现:毛细血管为窗孔型,基底膜外有生长抑素样阳性终末靠近。在阳性终末及非阳性终末内可见分泌囊泡。本结果提示人下丘脑内生长抑素系统在出生前已经发育并可能参与内分泌活动的调节。     

人胎胃壁瘦素及瘦素受体的免疫组织化学

目的：对不同胎龄胎儿胃壁组织发育和胃壁内瘦素及瘦素受体进行定性和定位观察。方法：采用HE和免疫组织化学SABC染色方法。结果：胚胎13w，可见有胃小凹和胃腺。15w时，胃壁具有4层结构。随胎龄增长，胃壁和胃腺逐步发育完善。胚胎13w时，胎儿胃粘膜上皮和胃腺内壁细胞呈瘦素及瘦素受体免疫反应中等阳性，免疫反应产物分布于胞质，而胞核为阴性。随着胃腺的发育，呈免疫反应阳性的壁细胞数目增多。在胎儿整个发育过程中，各胎龄间胃腺瘦素及瘦素受体的免疫反应强度无明显变化。结论：人胚胎发育时期，在胃上皮和胃腺中有瘦素及瘦素受体的表达，推测它们对胎儿的生长发育起重要的调节作用。     

P物质样免疫反应成分在人胎儿和新生儿脑干内的分布及在发育过程中的变化——免疫组织化学研究

应用免疫组织化学方法较系统地研究了p物质样免疫反应成分(SP-LI)在人眙儿(胎龄11.5周至35周)及新生儿(生后2天)脑干内的分布及其在发育过程中的变化,结果发现:SP-LI成分在人胎儿脑干最早出现于孕第三个月到孕四个月之间(孕11.5到16周);分布非常广泛,到孕六个月分布基本定型;SP-LI纤维和终末的密度及SP-LI细胞数量都随发育过程而显示一定的变化规律。有明确意义的发现是,参与内脏活动及内脏感觉的结构比参与躯体感觉的结构内SP-LI成分的量多;SP-LI成分出现早且较密集的区域主要为菱脑峡区,随胎龄的增加,此区域内的SP-LI成分也增加。     

人胎胰腺GnRH免疫反应细胞

目的：探讨促性腺激素释的激素(GnRH)免疫反应细胞在人胎胰腺的存在部位和数量变化。方法：用免疫组织化学SABC法，对37例第10-32w人胎胰腺内的GnRH-IR细胞进行观察，并用体视方法分析其数量变化。结果：人胎胰腺GnRH-IR细胞出现于第13w，其数密度随胎龄增加而增大；分布于胰岛及外分泌部的腺泡上皮、导管上皮细胞间。位于胰岛的GnRH-IR细胞呈圆形、卵圆形或多边形。位于腺泡上皮细胞间的GnRH-IR细胞多为锥体形，外分泌部的GnRH-IR细胞均为开放型细胞。结论：胰腺GnRH-IR细胞于胚胎第13w出现，广泛存在于内、外分泌部，其数量随胎龄增加而增加。     

Spatial and temporal dynamics of innervation during the development of fetal human pancreas

The delineation of pancreatic nerve innervation during fetal life may contribute to our understanding of pancreatic pain modalities after birth. The aim of this study was to characterize the spatial and temporal distribution of nerve structures in the human pancreas throughout gestation. Computer-based image morphometry with piecewise polynomial interpolation analysis was performed to quantify nervous structures in the head, body and tail of the pancreas. Nerve structures were detected by automatic immunostaining techniques using a polyclonal antibody against two S-100 proteins that reacts strongly with human S100A and B that are detected in Schwann cells. Immunoreactivity was found in the parenchyma of head, body and tail of the pancreas with the relative density being head>body>tail. In addition to this extensive set of nerve fibers terminating in the pancreas there were large bundles of en passant nerve fibers in the dorsal region of the pancreas that were 3D reconstructed and were associated with the superior mesenteric plexus. If at first glance, the perimeter and the width of the nerve fibers seem to increase at a continuous rate up to term in all three regions of the pancreas, spatial and temporal co-analysis identified that the head of the pancreas shows a two-peak growth increase at 14 and 22 weeks of gestation with regard to the area, perimeter and width of the nerve structures, while the body and tail regions show a unique peak at 20 weeks. A developmental deceleration was found between the 22nd and the 36th week of gestation for the head region only. This is the first systematic study of nerve innervation of the human pancreas throughout gestation. The developmental dynamics of the pancreas nerve innervation corresponds approximately to the remodeling of the intrahepatic biliary system. Understanding the factors and disease states that may alter the distribution of nerve structures can be of significance for the development of therapies in pancreatic disorders of child- and adulthood.     

Localization of acetylcholinesterase positive neurons and substance P and enkephalin positive fibers by histochemistry and immunohistochemistry in the sympathetic intermediate zone of the developing human spinal cord.

Localization of acetylcholinesterase positive neurons and substance P and enkephalin fibers were studied by histochemistry and immunohistochemistry in the intermediate sympathetic zone of the spinal cords of 39 human embryos/fetuses from gestation ages five to 40 weeks. Acetylcholinesterase positive neurons were observed in the nucleus intermediolateralis pars principalis as early as the fifth week of gestation. By the ninth to 13th weeks of gestation, positive neurons were also seen in the nuclei intermedialis pars funicularis, intercalatus spinalis and intercalatus pars paraependymalis. Increase in amount of these positive acetylcholinesterase neurons was demonstrated till term. Substance P and enkephalin fibers were initially observed by the eighth gestation week in the intermediolaterlis pars principalis nucleus and positive fibers were then detected in the nucleus intermedialis pars funicularis as well as the nucleus intercalatus spinalis by the 14th week of gestation. By the 26th week of gestation, all the major nuclei intermediolateralis par principalis, intermedialis pars funicularis, intercalatus spinalis and intercalatus pars paraependymalis has substance P and enkephalin fibers. Initial demonstration of acetylcholinesterase positive neurons appeared to be at an earlier stage than that of our substance P and enkephalin positive fibers.     

Fetal antigen 1 (FA1) in the human pancreas: cell type expression, topological and quantitative variations during development

Monospecific rabbit anti-human fetal antigen 1 (FA1), was used to examine the distribution of FA1 during the development of the human fetal pancreas and liver using an indirect immunoperoxidase technique. FA1 was expressed by 94% of the glandular epithelial cells of the branching ducts in the pancreatic anlage at week 7 of gestation. This pattern changed during the development of the human pancreas, 64% of the glandular cells being FA1 positive at week 17 of gestation, decreasing to 11% in the infant (4 months after birth). In the infant and adults the FA1 expression was restricted to a subpopulation of -cells within the islets of Langerhans. Insulin immunoreactive cells were scattered throughout the epithelium of primitive branching pancreatic ducts at week 7 of gestation, well before the formation of islets. From the 7th through to the 17th week of gestation, FA1 was found in the cytoplasm of fetal hepatocytes, whereas no staining was observed in the liver from a 4-month-old infant. No FA1 expression was found in the epithelium of the developing gut. The present findings indicate that the glandular epithelial cells in the developing pancreas may serve as stem cells, which, if appropriately induced, may differentiate into endocrine cells. Fetal antigen 1 (FA1) may take part in or be a result of this differentiation.     

Oct-4和人端粒酶逆转录酶在不同胎龄人胚原始生殖细胞的表达变化

目的 检测不同胎龄人胚原始生殖细胞中Oct-4、人端粒酶逆转录酶(hTERT)的表达变化.方法 取人胚胎生殖嵴,通过RT-PCR检测5～13周龄人胚生殖嵴中Oct-4、hTERT的表达变化;同时,取人胚胎生殖嵴,经石蜡切片,HE染色、免疫组织化学染色等技术,观察不同胎龄人胚原始生殖细胞的形态,检测Oct-4、hTERT的表达情况.结果 胎龄6～7周时,生殖嵴中可见少量原始生殖细胞,且表达Oct-4及hTERT;胎龄8～12周时,生殖嵴中原始生殖细胞数量增多,Oct-4及hTERT表达增强(P<0.05);胎龄13周以后,生殖嵴中Oct-4阳性的原始生殖细胞数量逐渐减少,Oct-4表达减弱,但hTERT仍然高表达.结论 不同胎龄人胚原始生殖细胞中Oct-4的表达呈动态变化,胎龄8～12周时表达较强,但hTERT的表达量始终维持在较高水平,没有明显变化.     

The urokinase plasminogen activator (u-PA) and its inhibitor (PAI-1) in embryo-fetal bone formation in the human: an immunohistochemical study

The role of urokinase plasminogen activator and plasminogen activator inhibitor-1 in human embryofetal bone formation between the 9th and the 20th week of gestation has been studied immunohistochemically. While mature osteocytes of the secondary spongiosa and resting chondrocytes of the bone epiphyses were negative for both antigens in each developmental stage, metabolically active parts of the osseocartilaginous system showed a strong immunoreactivity. Until the end of the 10th week of gestation urokinase plasminogen activator and plasminogen activator inhibitor-1 could not be demonstrated in the shaft of the preexisting cartilaginous models of bones, which correlates with the morphological developmental stage of the embryos. Later, osteoblasts and chondrocytes in the areas of enchondral ossification, and the perivascular chondrocytes of the epiphyseal secondary ossification centres, showed similarly high concentrations of urokinase plasminogen activator and plasminogen activator inhibitor-1. Moreover, the individual ossification stages of the different bones in embryo-fetal development could be demonstrated immunohistochemically. While humeri and femora showed diaphyseal immunoreactivities at an early stage, positive reactions in the phalanges were found only much later. Thus, the enzymes of the fibrinolytic system studied are clearly involved in the desmal and enchondral ossification process in the osseocartilaginous compartment.     

Supra-neuroectodermal cells and fibers on the primary nasal cavity and in the fourth ventricle of mouse and human embryos: scanning and transmission electron microscopic studies.

Neuroectoderm-derived epithelia of the primary nasal cavity and the fourth ventricular floor and roof were observed by scanning (SEM) and transmission electron microscopy (TEM) and SEM-TEM correlative views in mouse embryos of 9th to 13th days of gestation, and in 38 externally normal human embryos ranging at Carnegie stages from 13 to 18 (about 5 to 7 weeks of gestation). Smooth-surfaced spindle-shaped cells with one or more cytoplasmic processes and cord-like cytoplasmic structures were observed by SEM on the wall of the primary nasal cavity of both species. They had morphological features similar to those of neuronal type 1 supraependymal (SE) cells and SE fibers on the floor and roof of the fourth ventricle in both species. Type 1 SE cells, SE fibers, and corresponding structures in the primary nasal cavity were localized in relation to the underlying developing nerve and vascular systems. Furthermore, their processes and fibers ran roughly parallel to these underlying structures and they penetrated the epithelial layer at the ends, suggesting a connection with underlying structures. From TEM and SEM-TEM correlative observations, SE fibers in the fourth ventricle and cord-like structures in the primary nasal cavity, both with a larger diameter, were deduced as single axon-like processes or bundles of processes. Those fibers and cord-like structures of smaller diameters were interpreted as elongated telophase bridges; both contained parallel packed microtubules and connected distant cells. Since these processes and fibers were generally longer and became fewer at later developmental stages, they appeared to be transient neuronal structures. They may play a development-related role in such morphogenetic cell movements as in the developing nerve and vascular systems in the epithelial and/or subepithelial layers, but not as direct rudiments of adult nerve tissues.