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1.
The pattern of ovarian cancer metastasis is markedly different from that of most other epithelial tumors, because it rarely spreads hematogenously. Instead, ovarian cancer cells exfoliated from the primary tumor are carried by peritoneal fluid to metastatic sites within the peritoneal cavity. These sites, most notably the abdominal peritoneum and omentum, are organs covered by a mesothelium-lined surface. To investigate the processes of ovarian cancer dissemination, we assembled a complex three-dimensional culture system that reconstructs the lining of the peritoneal cavity in vitro. Primary human fibroblasts and mesothelial cells were isolated from human omentum. The fibroblasts were then mixed with extracellular matrix and covered with a layer of the primary human mesothelial cells to mimic the peritoneal and omental surfaces encountered by metastasizing ovarian cancer cells. The resulting organotypic model is, as shown, used to examine the early steps of ovarian cancer dissemination, including cancer cell adhesion, invasion, and proliferation. This model has been used in a number of studies to investigate the role of the microenvironment (cellular and acellular) in early ovarian cancer dissemination. It has also been successfully adapted to high throughput screening and used to identify and test inhibitors of ovarian cancer metastasis.  相似文献   

2.
In the silkmoth, Bombyx mori, mating accelerates egg laying. Sterilized males did not induce females to oviposit, whereas artificial insemination was enough to accelerate oviposition. These findings showed that mechanical stimulation of the outer reproductive organs and the bursa copulatrix (BC) had no effect on oviposition. Factors included in seminal fluids also did not stimulate oviposition because neither implantation of female internal reproductive organs nor injection of the spermatophore extract into virgin females activated oviposition. Preventing sperm precedence by experimental removal of the BC or spermatheca inhibited activation of egg laying. More precise surgeries on the spermatheca showed that the main factor for eliciting oviposition was the presence of matured and fertile eupyrene spermatozoa in the vestibulum. Sperm were not effective unless they reached the vestibulum. Nerve transection and electrophysiological studies revealed that nerve 4 of the terminal abdominal ganglion was the pathway by which the mating signal was transmitted toward the higher central nervous system.  相似文献   

3.
The present histochemical study was carried out to analyze the distribution and topography of acetylcholinepositive nerve fibers in the thymus and bursa of Fabricius of quails. The AChE-positive nerve fibers were demonstrated by direct thiocholine histochemical method. Nerve fibers present in the thymuses form periarterial nerve plexuses located mostly in the interlobular septa and on the cortico-medullary junction. Vessels-independent nerve fibers occur also in the parenchyma of thymic medulla, but rarely in parenchyma of the cortex. Within the connective tissue between the bursa of Fabricius and the wall of proctodeum we observed conspicuous AChE-positive ganglia, often in close relationship to greater arteries. Within the wall of bursa of Fabricius, AChE-positive nerve fibers create nerve plexuses around arteries. We observed a close relationship between lymphoid follicules in bursal submucosa and mucosa and AChE-positive nerve fibers. Nerve fibers create a ring around lymphoid follicles, but do not penetrate into the germinal center of the follicle. Arteries inside quail thymuses and bursae of Fabricius contain rich AChE-positive nerve plexuses, when compared to the veins, which have a very poor presence of AChE-positive nerves. According to lesser presence and decreased density of AChE-positive nerve fibers in older animals, we described age-dependent changes in both quail primary lymphoid organs.  相似文献   

4.
Extremely elongated intromittent organs are found in a wide range of taxa, especially among insects. This phenomenon is generally thought to result from sexual selection, but it is predicted that limited storage space in the body cavity and the difficulty of using the elongated organs should have constrained the evolution of extreme elongation, neutralizing any selective advantage. Therefore, in groups with long intromittent organs, features that overcome these constraints may have evolved or coevolved together with intromittent organ elongation. Using a comparative morphological approach and outgroup comparisons, we identified potential constraints and key novelties that may neutralize such constraints in the leaf beetle subfamily Criocerinae. Observations of the internal sac structure throughout Criocerinae were performed. Comparing the results with preceding studies from outgroups, a ground plan of the criocerine internal sac was constructed. Our analysis also identified specific features that are always correlated with extreme elongation: the rotation of whole internal‐sac sclerites and the possession of a pocket in which to store the elongated flagellum. The pocket is thought to be formed by the rotation of the sclerites, markedly altering internal sac shape from the criocerine ground plan. Onlythe clades that have acquired this derived state contain species with an elongated flagellum that distinctly exceeds the median lobe length. It is presumed that these character correlations evolved independently three times. The detected character correlations corroborate the hypothesis that there are latent adaptive constraints for the evolution of extremely elongated intromittent organs. The constraints may have been neutralized by the alteration from the criocerine ground plan resulting in the formation of a storage pocket. In conclusion, deviation from the criocerine ground plan isconsidered to be the evolutionary innovation that neutralized the latent adaptive constraints of flagellum elongation in the subfamily Criocerinae. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

5.
The peritoneum, especially the omentum, is a common site for gastric cancer (GC) metastasis. Our aim was to expound the role and mechanisms of Piezo1 on GC omentum metastasis. A series of functional assays were performed to examine cell proliferation, clone formation, apoptosis, Ca2+ influx, mitochondrial membrane potential (MMP) and migration after overexpression or knockdown of Piezo1. A GC peritoneal implantation and metastasis model was conducted. After infection by si-Piezo1, the number and growth of tumours were observed in abdominal cavity. Fibre and angiogenesis were tested in metastatic tumour tissues. Piezo1 had higher expression in GC tissues with omentum metastasis and metastatic lymph node tissues than in GC tissues among 110 patients. High Piezo1 expression was associated with lymph metastasis, TNM and distant metastasis. Overexpressed Piezo1 facilitated cell proliferation and suppressed cell apoptosis in GC cells. Moreover, Ca2+ influx was elevated after up-regulation of Piezo1. Piezo1 promoted cell migration and Calpain1/2 expression via up-regulation of HIF-1α in GC cells. In vivo, Piezo1 knockdown significantly inhibited peritoneal metastasis of GC cells and blocked EMT process and angiogenesis. Our findings suggested that Piezo1 is a key component during GC omentum metastasis, which could be related to up-regulation of HIF-1α.  相似文献   

6.
Septic peritonitis occurs relatively commonly in dogs. Secondary septic peritonitis is usually associated with perforation of intestines or infected viscera, such as the uterus in pyometra cases. The aim of this study was to evaluate the bacterial flora in the ovarian bursae of intact bitches as a potential source of contamination. One hundred forty dogs, clinically suspected of pyometra, were prospectively enrolled. The control group consisted of 26 dogs that underwent elective ovariohysterectomies and 18 dogs with mammary gland tumors that were neutered at the time of mastectomy. Bacteriology samples were taken aseptically at the time of surgery from the bursae and the uterus in all dogs. Twenty-two dogs that were clinically suspected of pyometra had sterile uterine content (“mucometra” cases); the remaining 118 had positive uterine cultures (“pyometra” cases) and septic peritoneal fluid was present in 10% of these cases. Of the 118 pyometra cases, 9 had unilateral and 15 had bilateral bacterial colonization of their ovarian bursae. However, the bacteria from the ovarian bursa were similar to those recovered from the uterine pus in only half of the cases. Furthermore, positive bursae were also seen in one mucometra dog (unilateral) and in four control dogs (two unilateral and two bilateral). The data illustrate that the canine ovarian bursa can harbor bacteria. The biological importance of these isolations remains unclear.  相似文献   

7.
粉尘螨生殖系统形态学研究   总被引:1,自引:1,他引:0  
吴桂华  刘志刚  孙新 《昆虫学报》2008,51(8):810-816
粉尘螨Dermatophagoides farinae是一种重要的医学螨类。本文用光镜和扫描电镜研究了粉尘螨雌雄生殖系统的形态和结构。结果表明:雄性生殖系统由睾丸、输精管、 附腺、射精管、阳茎及附属交配器官组成。睾丸位于血腔末端,不成对,精原细胞、精母细胞和精子依照精子发育的顺序有规则地分布在其内部。雌性生殖系统包括交配孔、囊导管、储精囊、囊导管、卵巢、输卵管、子宫、产卵管及产卵孔,其中卵巢由一个中央营养细胞和围绕其周围的卵母细胞组成。  相似文献   

8.
The formation of both the anterior most and posterior most segments in higher dipteran embryos involves complex movements of primordia which can be best visualized with the scanning electron microscope. During head formation, the gnathocephalic segments partially involute through the stomodeum. The labial segment forms the floor of the mouth, and the fused maxillary and mandibular segments form the lateral sides of the mouth. The involuted clypeolabrum forms the roof of the mouth. Invaginations of cells for segmentally derived sense organs can be found prior to involution on all the gnathocephalic and thoracic segments as well as on the labrum. The antennal sense organ derives from the lateral surface of the procephalic lobe. Following involution of the mouth parts, the dorsal ridge, which arises just anterior to the first thoracic segment, is drawn over the dorsal procephalic lobe producing the deep dorsal sac. The optic lobes of the brain invaginate anterior to the dorsal ridge just prior to the covering over of the head. The formation of the anal segment is similarly complex. Two rudimentary segments are found posterior to the eighth abdominal segment. During shortening of the germ band, the posterior most segment is drawn around the posterior tip of the embryo to lie ventrally. Two large anal pads form lateral to the anus from this segment. The next segment, following dorsal closure, produces a pair of anal sense organs and a central tuft of setae. Finally, the eighth abdominal segment gives rise to the posterior spiracles. Following dorsal closure these three segments fuse to produce the terminal (anal) segment of the larva.  相似文献   

9.
In view of the extensive operation required for repair of hiatus hernia by transthoracic or abdominal approach, herniotomy was done in three cases. Objectives were to (a) widen the esophageal hiatus, (b) remove the hernial sac, (c) cut the structures of the omentum and lesser curvature so that the stomach would lie flat in the chest, and (d) fix the stomach at the new level. After the operation, all three patients were free of the symptoms of indigestion of which they had previously complained.  相似文献   

10.
The topography and splanchnology of the reproductive organs of the African lioness were studied and described in situ and after removal. The kidneys were located far caudally in relation to the thirteenth ribs. The suspensory ligament was very well developed, originated in a fan‐like manner from the dorsolateral abdominal wall lateral to the kidney and extended up to a few centimetres cranial to the kidney. The proper ligament of the ovary as well as the round ligament was well developed. The round ligament inserted on the medial femoral fascia. The left ovary was bigger than the right. The ovarian bursa had a short mesosalpinx that did not cover any part of the ovary and the fimbriae extended along the entire length. The urethral tuberculum as well as the urethral crest were well developed. The left uterine horn was longer than the right. The uterine tube was found to open directly into the tip of the uterine horn and not onto a papilla. The reproductive organs of the lioness resembled those of the domestic cat and dog but with some major differences.  相似文献   

11.
Coelomic cavities are relatively isolated from the systemic circulation of blood cells. Resident cell populations have a proper phenotype and kinetics, maintaining their steady-state populations and their responsiveness to local inflammatory reactions, in which the number and quality of coelomic cells can be greatly increased and modified. We have addressed the question of whether the increase in cell infiltrate in the inflamed abdominal cavity is sustained by the proliferation of myeloid cells in the omentum, and if so what are the characteristics of the progenitor cells involved and how the omentum controls their proliferation and differentiation. In the omentum under normal conditions and with inflammation due to schistosomal infection we found that pluripotent early myeloid progenitors were capable of giving rise to all the myeloid lineages in clonogenic assays, but not to the totipotent blood stem cells. Besides the major haemopoietins (GM-CSF, M-CSF, G-CSF, IL-5), the omentum stroma constitutively expressed SDF-1 alpha, the chemokine which elicits homing of circulating early haemopoietic progenitors. While normal omentum stroma produced LIF, its expression was substituted by SCF in inflamed tissues. In the first situation a slow steady-state renewal of progenitors is potentially favoured, while their intense expansion may be predominant in the latter one. We propose that the increase in cells in the abdominal cavity in inflammatory reactions is due to the enhanced input and expansion of early myeloid progenitors sustaining the in situ production of abdominal cell populations, rather than to the input of systemic circulating inflammatory cells.  相似文献   

12.
In view of the extensive operation required for repair of hiatus hernia by transthoracic or abdominal approach, herniotomy was done in three cases. Objectives were to (a) widen the esophageal hiatus, (b) remove the hernial sac, (c) cut the structures of the omentum and lesser curvature so that the stomach would lie flat in the chest, and (d) fix the stomach at the new level.After the operation, all three patients were free of the symptoms of indigestion of which they had previously complained.  相似文献   

13.
豚鼠卵巢囊淋巴孔的发现及卵巢囊超微结构研究   总被引:6,自引:1,他引:5  
In order to explore its structure and speciality of species, the ovary bursa of guinea pig was studied by using dissecting microscopy and scanning electron microscopy. In this paper, the lymphatic stomata on both internal and external layer of the ovary bursa was frist reported in guinea pig. The results suggested that the stomata in bursa not only provided a pathway to connect the bursal cavity with the lymphatic vessels of bursa and the peritoneal cavity, but also may be involved in the reproduction and local immunity of the ovary. The stomata may play an important role in physiological function of the ovary. At the same time, the structural differences were identified in ovary bursa between guinea pig and golden hamster.  相似文献   

14.
We previously reported that B lymphocyte chemoattractant (BLC; CXCL13) was highly and ectopically expressed in aged (NZB x NZW)F1 (BWF1) mice developing lupus nephritis, and that B1 cells were preferentially chemoattracted toward BLC. We demonstrate in this study that B1 cells fail to home to the peritoneal cavity in aged BWF1 mice developing lupus nephritis, and that they are preferentially recruited to the target organs including the kidney, lung, and thymus when injected i.v. In contrast, B1 cells homed to the peritoneal cavity in aged BALB/c mice as effectively as in young mice. Accumulation of B1 cells to the omentum milky spots was also impaired in aged BWF1 mice compared with young mice. CD11bhighF4/80high cells with macrophage morphology were confirmed to be a major cell source for BLC in the peritoneal cavity both in young and aged BWF1 mice. However, the number of BLC-producing peritoneal macrophages was markedly decreased in aged BWF1 mice. These results suggest that the decreased number of BLC-producing peritoneal macrophages together with ectopic high expression of BLC in aged BWF1 mice result in abnormal B1 cell trafficking during the development of murine lupus.  相似文献   

15.
The humoral influence of cells of hemopoietic organs of chicken embryos of different terms on the development of the colony and cluster formation of mononuclears of the bone marrow of mice was studied in joint cultivation in two-compartment cylindrical diffuse microchambers. The process of formation of colonies and clusters is inhibited by cells of the yolk sac on the 2nd-4th day of the development, by cells of the liver on the 8th-12th day, of the spleen on the 13th-18th day and of the bone marrow--on the 15th day. The yolk sac cells were found to have most considerable inhibiting influence on proliferation and differentiation of cells on the 2nd day of the development of chicken embryo. The yolk sac cells on the 6th day stimulate the formation of colonies and clusters. The yolk sac, beginning from the 4th day of the development, and the liver release humoral factors promoting the formation of erythroid colonies. The erythroid colonies are formed but when cultivated on the vascular membrane of the chicken embryo; the erythroid colonies are not formed when cultivated in the abdominal cavity of mice. Local erythropoietinoid factors are not synthetized by the spleen and bone marrow cells. A supposition is put forward that a combination of the local inhibiting and erythropoietic effects promotes the erythroid differentiation of cells.  相似文献   

16.
The constitutive migration of B cells from the circulation into the peritoneal cavity and back is essential for peritoneal B cell homeostasis and function. However, the molecular machinery and the anatomical basis for these migratory processes have hardly been investigated. In this study, we analyze the role of integrins as well as the role of the omentum for B2 cell migration into and out of the peritoneal cavity of mice. We demonstrate that alpha(4)beta(7) integrin-mucosal addressin cell adhesion molecule 1 interaction enables B2 cell migration from the circulation into omental milky spots but not into the peritoneum. In contrast, alpha(4)beta(1) integrin mediates direct entry of B2 cells into the peritoneal cavity as well as their retention at that site, limiting B2 cell egress via the draining parathymic lymph nodes. Surgical removal of the omentum results in a 40% reduced immigration of B2 cells from the circulation into the peritoneum but does not impair B cell exit from this compartment. In conclusion, these data reveal the existence of alternative routes for B2 cell entry into the peritoneal cavity and identify integrins as key factors for peritoneal B2 cell homeostasis, mediating B2 cell migration into and out of the peritoneal cavity as well as their retention at this site.  相似文献   

17.
Vascular endothelial growth factor A (VEGFA) plays a pivotal role in the first steps of endothelial and haematopoietic development in the yolk sac, as well as in the establishment of the cardiovascular system of the embryo. At the onset of gastrulation, VEGFA is primarily expressed in the yolk sac visceral endoderm and in the yolk sac mesothelium. We report the generation and analysis of a Vegf hypomorphic allele, Vegf(lo). Animals heterozygous for the targeted mutation are viable. Homozygous embryos, however, die at 9.0 dpc because of severe abnormalities in the yolk sac vasculature and deficiencies in the development of the dorsal aortae. We find that providing 'Vegf wild-type' visceral endoderm to the hypomorphic embryos restores normal blood and endothelial differentiation in the yolk sac, but does not rescue the phenotype in the embryo proper. In the opposite situation, however, when Vegf hypomorphic visceral endoderm is provided to a wild-type embryo, the 'Vegf wild-type' yolk sac mesoderm is not sufficient to support proper vessel formation and haematopoietic differentiation in this extra-embryonic membrane. These findings demonstrate that VEGFA expression in the visceral endoderm is absolutely required for the normal expansion and organisation of both the endothelial and haematopoietic lineages in the early sites of vessel and blood formation. However, normal VEGFA expression in the yolk sac mesoderm alone is not sufficient for supporting the proper development of the early vascular and haematopoietic system.  相似文献   

18.
采用组织学方法比较研究细尾高原鳅和东方高原鳅组织器官的黑色素分布特征。结果显示: 两种高原鳅头部皮肤、背部皮肤、体侧皮肤、腹膜肾脏层、脊髓腔壁层、腹膜壁层、围心腔壁层、脑颅腔壁层和眼睛均分布有黑色素;腹部皮肤、肝脏浆膜、脾脏被膜和性腺被膜未发现黑色素。皮肤中黑色素分布在真皮层和皮下组织,其他组织器官中黑色素分布在内膜层或壁层。黑色素主要分布在背侧,体侧则分布稀疏,呈现对称分布。背部和体侧皮肤有斑块处较无斑块处黑色素数量多,分布密集;无斑块处仅是部分聚集,或形成间断分布的黑色素块。同一种高原鳅不同组织器官黑色素分布不同,分布面积百分比和黑色素层厚度有显著性差异,但两种高原鳅同一组织器官黑色素分布特征相似。两种高原鳅组织器官中黑色素的分布与其接受的紫外辐射强度有关,是对高原强紫外辐射环境的适应。  相似文献   

19.
An 10-y-old, intact male rhesus macaque (Macaca mulatta) presented for bilateral scrotal swelling and a distended abdomen. A soft mass in the left upper quadrant of the abdomen was palpated. A barium study did not reveal any gastrointestinal abnormalities. Exploratory laparotomy revealed a large (1.25 kg, 15.0 × 13.0 × 9.5 cm), red and tan, soft, circumscribed, spherical mass within the greater omentum and 10 to 20 smaller (diameter, 1 to 4 cm), soft to firm masses in the mesentery and greater omentum. The resected mass was a self-strangulating abdominal lipoma, a pedunculated neoplasm composed of white adipocytes arising from peritoneal adipose tissue undergoing secondary coagulation necrosis after strangulation of the blood supply due to twisting of the mass around the peduncle. The smaller masses were histologically consistent with simple or self-strangulating pedunculated abdominal lipomas. The macaque presented again 9 mo later with a firm, 5.0-cm mass in the midabdomen, with intestinal displacement visible on radiographs. Given this animal''s medical history and questionable prognosis, euthanasia was elected. Necropsy revealed numerous, multifocal to coalescing, 1.0- to 15.0-cm, pale tan to yellow, circumscribed, soft to firm, spherical to ellipsoid, pedunculated masses that were scattered throughout the mesentery, greater omentum, lesser omentum, and serosal surfaces of the gastrointestinal tract. All of the masses were pedunculated abdominal lipomas, and most demonstrated coagulation necrosis due to self-strangulation of the blood supply. To our knowledge, this report is the first to describe abdominal lipomatosis with secondary self-strangulation of masses in a rhesus macaque.Lipomas have been reported frequently in veterinary medicine as benign subcutaneous neoplasms in canines16 or as pedunculated peritoneal masses with the potential to cause intestinal strangulation in geriatric horses.6 Abdominal lipomatosis (multiple abdominal lipomas) in humans and dogs had been reported only rarely and have been accompanied by clinical signs of abdominal distention with or without secondary gastrointestinal complications.16 Lipomas of the skin of nonhuman primates have affected a patas monkey, an African green monkey, rhesus macaques, and chimpanzees. Lipomas within the peritoneal cavity have been diagnosed rarely in nonhuman primates. Reported cases include an omental lipoma in a mona monkey and an adrenal lipoma in a hamadryas baboon.14 Here we report the clinical signs, postmortem examination, and histopathologic features of abdominal lipomatosis in a rhesus macaque (Macaca mulatta).  相似文献   

20.
采用组织学方法比较研究细尾高原鳅和东方高原鳅组织器官的黑色素分布特征。结果显示: 两种高原鳅头部皮肤、背部皮肤、体侧皮肤、腹膜肾脏层、脊髓腔壁层、腹膜壁层、围心腔壁层、脑颅腔壁层和眼睛均分布有黑色素;腹部皮肤、肝脏浆膜、脾脏被膜和性腺被膜未发现黑色素。皮肤中黑色素分布在真皮层和皮下组织,其他组织器官中黑色素分布在内膜层或壁层。黑色素主要分布在背侧,体侧则分布稀疏,呈现对称分布。背部和体侧皮肤有斑块处较无斑块处黑色素数量多,分布密集;无斑块处仅是部分聚集,或形成间断分布的黑色素块。同一种高原鳅不同组织器官黑色素分布不同,分布面积百分比和黑色素层厚度有显著性差异,但两种高原鳅同一组织器官黑色素分布特征相似。两种高原鳅组织器官中黑色素的分布与其接受的紫外辐射强度有关,是对高原强紫外辐射环境的适应。  相似文献   

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