首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Hemangiomas are considered tumors originating in blood vessels and are classified as ectatic and hyperplastic. Controversy regarding active therapy occurs in the case of strawberry hemangiomas which are hyperplastic capillary hemangiomas. Although they may clear up spontaneously, on rare occasions they may predispose to grave sequelae. Port-wine stain hemangiomas should never be treated with x-ray or radium.  相似文献   

2.
Infantile hemangiomas are common vascular tumours which exhibit a rapid proliferating phase followed by spontaneously involuting for a long time. The formation and development mechanisms are not clear yet. Recent studies show that hemangioma-derived stem cells have multipotential differentiation abilities, including endothelial and mesenchymal differentiation. In addition, mesenchymal stem cell has the capability of inducing endothelial cell apoptosis, differentiating into adipocytes and triggering the involution of hemangiomas. Thus we hypothesize that mesenchymal stem cell may be the source of spontaneously regression of hemangiomas. Further investigations may be needed to develop potential therapeutic implications of mesenchymal stem cell in treating hemangiomas.  相似文献   

3.
Hemangiomas are benign endothelial tumors. Often referred to as hemangiomas of infancy (HOI), these tumors are the most common tumor of infancy. Most of these lesions proliferate rapidly in the first months of life, and subsequently slowly involute during early childhood without significant complications. However, they often develop on the head or neck, and may pose a significant cosmetic concern for families. In addition, a fraction of these tumors can grow explosively and ulcerate, bleed, or obstruct vision or airway structures. Current treatments for these tumors are associated with significant side effects, and our knowledge of the biology of hemangiomas is limited. The natural evolution of these lesions creates a unique opportunity to study the changes in gene expression that occur as the endothelium of these tumors proliferates and then subsequently regresses. Such information may also increase our understanding of the basic principals of angiogenesis in normal and abnormal tissue. We have performed large-scale genomic analysis of hemangioma gene expression using DNA microarrays. We recently identified insulin-like growth factor 2 as a potentially important regulator of hemangioma growth using this approach. However, little is known about the mechanisms involved in hemangioma involution. Here we explore the idea that hemangioma involution might be an immune-mediated process and present data to support this concept. We also demonstrate that proliferating hemangiomas express indoleamine 2,3 dioxygenase (IDO) and discuss a possible mechanism that accounts for the often slow regression of these lesions.  相似文献   

4.
Hemangiomas are the most common benign tumor of infancy. Although most hemangiomas remain asymptomatic, certain hemangiomas can cause significant morbidity and require treatment. Periocular hemangiomas require close observation and early therapy for those lesions with potential for visual impairment. Hemangiomas typically cause visual morbidity by induction of amblyopia, strabismus, significant refractive error or optic nerve compromise. Diagnosis is typically straightforward but occasionally other entities may cause diagnostic confusion and radiologic evaluation can be helpful. This is particularly important if the hemangioma is one component of the PHACES syndrome. Therapeutic options which may be useful include steroids (oral, intralesional or topical), interferon alpha (usually reserved for life- or sight-threatening lesions due to serious potential side effects), laser, embolization and surgery. Ophthalmic treatment using patching, atropine, glasses and stabismus surgery may be necessary.  相似文献   

5.
Prospective investigation has been undertaken with the aim to study the frequency, location and age and sex distribution of various histological types of benign gastric epithelial polyps. Histological type--adenomatous, hyperplastic and fundic gland polyps--was diagnosed on the basis of at least three histological samples taken from the polyp. Biopsy samples were also taken from the antrum and the body of the stomach so that gastritis could be graded and classified, and the presence of H. pylori could be determined by histology. All 6,700 patients, who had undergone upper gastrointestinal endoscopy in a one-year period, participated in this study. Among them 42 benign gastric epithelial polyp were found in 31 patients: adenomatous gastric polyps in 7 patients, hyperplastic gastric polyp in 21 and fundic gland polyp in 3 patients. All patients with hyperplastic polyps had chronic active superficial gastritis, whereas most of the patients with adenomatous polyps had a chronic atrophic gastritis with high prevalence of intestinal metaplasia. Among 21 patients with hyperplastic gastric polyps, 16 (76%) patients were positive for H. pylori infection in contrast to only 2 patients (29%) with adenomatous gastric polyps and 1 patient (33%) with fundic gland polyp. Presented data indicates that hyperplastic gastric polyps are the most common and they are associated with the presence of chronic active superficial gastritis and concomitant H. pylori infection. Adenomatous polyps are rarer and they tend to be associated with chronic atrophic gastritis and intestinal metaplasia. Fundic gland polyp is the rarest type of gastric polyps.  相似文献   

6.
The pathogenesis of hemangiomas still remains poorly understood. Dysregulation of angiogenesis has been proposed to play a central role in hemangioma pathogenesis. The aim of our study was to determine the peripheral and local serum levels of VEGF in patients with hemangiomas and vascular malformations. Material and methods: The study group consisted of 52 children with infantile hemangioma (33 with proliferative lesions, 19 with involuting lesions), 14 children with vascular malformations and 36 healthy children. VEGF serum levels were analyzed by an ELISA assay and the values between the groups were compared. Results: The serum peripheral VEGF concentrations in children with proliferative hemangiomas were significantly higher than in patients with involuting hemangiomas, vascular malformations and controls. There was no correlation between the measured cytokine level, hemangioma size, and the age of the patients. The local serum VEGF levels in 29 children with hemangiomas were distinctly lower than in the peripheral blood, both in 20 proliferating hemangiomas (p < 0.0001) and 9 involuting ones (p = 0.007); and the difference between females and males was non-significant (NS p = 0.06). Conclusions: (1) VEGF serum levels vary in the different phases of hemangioma growth and may help to distinguish hemangiomas from vascular malformations; (2) obtained local results may support the intrinsic theory of endothelial cell proliferation in hemangiomas.  相似文献   

7.
Fifty-two patients with cavernous hemangiomas were therapeutically coagulated by use of percutaneous copper needles. Of the 52 patients, 32 had cavernous hemangiomas of the face and neck and 20 had cavernous hemangiomas of the trunk and extremities. All have gained effective treatment. Through in vitro tests, animal experiments, and clinical studies, I have confirmed that copper needles produce coagulation and destruction of cavernous hemangiomas. The mechanism, indications, technique, prevention and treatment of complications, and an analysis of copper concentrations in the patients' blood are discussed. My conclusion is that this is a simple, safe, and effective treatment for cavernous hemangiomas.  相似文献   

8.
Hemangiomas are benign neoplasms of the vasculature frequently encountered in children. Several studies have shown that these tumors are characterized by excessive angiogenesis. Although benign, the lesions can present with complications, and may thus require treatment. There are multiple therapeutic options available for patients with problematic or life threatening hemangiomas, some of which have serious side effects. Randomized clinical trials and evidence-based studies on the efficacy of these treatments is still lacking. The recognition that excessive angiogenesis underlies hemangiogenesis offers an opportunity for the development of safer therapeutic strategies that are based on the inhibition of angiogenesis. We review medical therapies currently employed in the management of hemangiomas and the role of angiogenesis inhibition in hemangioma therapy.  相似文献   

9.
Carbonic anhydrase (CA) IX and XII are transmembrane isoenzymes which are expressed in several epithelia and overexpressed in some carcinomas. They have recently been linked to von Hippel-Lindau gene-mediated carcinogenesis in that both isoenzymes are downregulated by the product of the wild-type von Hippel-Lindau tumour suppressor gene. This paper describes the localisation of CA IX and XII in the normal human pancreas and pancreatic tumours. Both isoenzymes showed positive reaction in the basolateral plasma membrane of the normal acinar and ductal epithelia. The hyperplastic ductal epithelium in tumour specimens generally showed an increased staining for CA IX. Of 29 malignant tumours of exocrine pancreas, 10 showed moderate or strong immunoreaction for CA IX. The signal for CA XII remained weak in most malignant lesions. The present results show that both CA IX and XII are unevenly expressed in the ductal and acinar compartments of the human pancreas. The expression of these isoenzymes in a relatively low number of malignant tumour specimens suggests that they have a limited value in diagnostic evaluation of pancreatic carcinoma. However, the increased expression of CA IX in hyperplastic ductal epithelium may contribute to the pancreatic tumourigenesis.  相似文献   

10.
Electron microscopy of sugarbeet leaves infected with the beet curly top virus confirmed earlier findings by light microscopy that the hyperplastic phloem consists mainly of sieve elements that are more or less abnormal in structure. Some parenchyma cells and occasional companion cells may be present. The hyperplastic phloem develops in the place of normal phloem and sometimes in the adjacent ground tissue and the xylem. The sieve elements vary in shape and may be haphazardly arranged. The protoplasts of the sieve elements have the usual characteristics of this type of cell. The sieve element plastids develop from chloroplasts if the hyperplasia occurs in chloroplast-containing parenchyma cells. The cell walls have sieve areas that often are less well differentiated than those of normal sieve elements. The hyperplastic growth in the phloem of curly top diseased plants is discussed with reference to plant tumors induced by certain other plant viruses.  相似文献   

11.
Hemangiomas of infancy are very common tumors, but they are heterogeneous in their behavior. A small, but significant, subset causes medical complications or permanent disfigurement, but due to their heterogeneity, there is no appropriate "one size fits all" approach to management. In addition, the rapid evolution of this tumor over the first weeks-to-months of infancy renders even more difficult the task of predicting which infants will have medical complications or permanent disfigurement. This article outlines the clinical characteristics that help to stratify hemangiomas into those which are high risk, and likely to require either active treatment or closer scrutiny, and those which are low risk, and likely to behave in an innocuous manner. Five major factors are emphasized: the age of the child, the location of the hemangioma(s), the total number of hemangiomas present, the hemangioma subtype, and the presence and nature of dermal involvement.  相似文献   

12.
We studied the distribution of the four human apomucins MUC1, MUC2, MUC4, and MUC5AC in hyperplastic polyps, serrated adenomas, and traditional adenomas of the colorectum using immunohistochemical techniques, with the aim of comparing and contrasting their patterns of expression. A series of 12 hyperplastic polyps, 27 serrated adenomas, and 20 traditional adenomas was studied. No significant change in apomucin expression was observed in traditional adenomas compared with normal colorectal epithelium, except for MUC5AC, which was present in 12 of the adenomas (60%) and only 20% of the normal samples. In both hyperplastic polyps and serrated adenomas, MUC2 and MUC5AC mucin expression was consistently and markedly increased. In 50% of the hyperplastic polyps, MUC4 was reduced but in the remaining cases was similar to normal. Loss of MUC4 expression was observed in all serrated adenomas. MUC1 was not increased in the hyperplastic polyps but increased expression was seen in 17 of the serrated adenomas (63%). Similar altered distribution patterns of MUC2, MUC4, and MUC5AC were seen in hyperplastic polyps and serrated adenomas, whereas traditional adenomas showed little change from normal patterns of expression. Although hyperplastic polyps are commonly defined as benign lesions without neoplastic potential, the similar phenotypes of hyperplastic and serrated adenomas and the existence of mixed polyps suggest that these lesions may represent a histogenetic continuum.  相似文献   

13.
BACKGROUND: Placental hemangioma (chorioangioma) and congenital hemangioma are relatively common tumors, which on rare occasions may occur together. Very little is known about the pathogenetic mechanisms underlying these lesions. CASE: Herein we describe a rare case of a stillborn infant with chorioangioma, placental mesenchymal dysplasia, and liver cavernous hemangioma. In addition, we present the findings of the karyotype analysis of these lesions, which was done with the bacterial artificial chromosome arrays using the comparative genomic hybridization method. The chromosomal abnormalities that we found were deletions at 2q13 and 7p21.1 and were common to both placental and liver lesions. CONCLUSIONS: None of the identified chromosomal aberrations have been previously associated with chorioangiomas or hemangiomas. Important genes that lie in these DNA regions may be implicated in the pathogenesis of congenital hemangiomas and mesenchymal dysplasia.  相似文献   

14.
Although the majority of hemangiomas of infancy undergo an uncomplicated, predictable course of proliferation followed by involution, a subset of patients sustain a more fastidious course. These include hemangiomas that, at least during part of their life cycle, have a high flow (arterial) component. Hemangiomas with high flow are most frequently located in the liver. These lesions can lead to significant morbidity, with high output cardiac failure. We have identified nonhepatic hemangiomas that have an apparent propensity to develop a high flow element--the parotid, upper arm, scalp, and rarely the upper lip--and present our experience in this report. These lesions appear to behave as transiently "arterialized" hemangiomas.  相似文献   

15.
A combined use of radiation methods in the diagnosis of liver hemangiomas is considered. Twenty-two hemangiomas were detected in 18 patients using ultrasound investigation (USI), computerized tomography (CT) and angiography. The most characteristic signs of hemangiomas were identified. USI and CT were shown quite reliable in the detection of hemangiomas. They can be used for solving diagnostic problems depending on a situation. A diagnostic algorithm envisaging the most optimum use of USI, CT and angiography in liver hemangiomas, was developed.  相似文献   

16.
Nevi are the most common tumors of childhood. Pigmented nevi are classified into blue nevi, intraepidermal nevi, junction nevi, intradermal nevi (or common mole) and combination types. Cutaneous malignant disease in children is rare. Malignant melanoma is rare before puberty. Wholesale removal of benign pigmented nevi in children should be condemned. However, junction nevi located on the palms, soles, genitalia or waistline-that is, in areas subject to frequent trauma-should be excised. Hemangiomas in infants are the most common tumors for which advice is sought. Not all hemangiomas regress spontaneously, and on occasion the persistence or progression of such a lesion may bring about life-long unsightly deformities. Therapy for this type of tumor is simple when given early in life. Hemangiomas involving the ears, nose, lips or eyelids should be treated at once, preferably within a month of the time they appear.  相似文献   

17.
The vast majority of cyanophages isolated to date are cyanomyoviruses, a group related to bacteriophage T4. Comparative genome analysis of five cyanomyoviruses, including a newly sequenced cyanophage S-RSM4, revealed a 'core genome' of 64 genes, the majority of which are also found in other T4-like phages. Subsequent comparative genomic hybridization analysis using a pilot microarray showed that a number of 'host' genes are widespread in cyanomyovirus isolates. Furthermore, a hyperplastic region was identified between genes g15–g18 , within a highly conserved structural gene module, which contained a variable number of inserted genes that lacked conservation in gene order. Several of these inserted genes were host-like and included ptoX , gnd , zwf and petE encoding plastoquinol terminal oxidase, 6-phosphogluconate dehydrogenase, glucose 6-phosphate dehydrogenase and plastocyanin respectively. Phylogenetic analyses suggest that these genes were acquired independently of each other, even though they have become localized within the same genomic region. This hyperplastic region contains no detectable sequence features that might be mechanistically involved with the acquisition of host-like genes, but does appear to be a site specifically associated with the acquisition process and may represent a novel facet of the evolution of marine cyanomyoviruses.  相似文献   

18.
Soft-tissue vascular lesions in children can be classified as either hemangiomas or vascular malformations. The distinction between the two has important prognostic and therapeutic implications. Over the past 8 years, we have evaluated 64 vascular lesions with the technetium-labeled red blood cell (Tc-RBC) scan. Twenty-eight lesions imaged as hemangiomas with intense focal uniform uptake. This diagnosis was confirmed in 27 lesions, or 96 percent. Thirty-six lesions imaged as vascular malformations with abnormal vessels or diffusely increased activity. This diagnosis was confirmed in 35 lesions, or 97 percent. Overall, the Tc-RBC scan was 97 percent accurate in distinguishing hemangiomas from vascular malformations. It is particularly useful when the clinical diagnosis of the lesion may not be evident. Not only can biopsy be avoided, but parents can be reassured at an earlier age and given accurate information regarding prognosis.  相似文献   

19.
Infantile hemangiomas are localized lesions comprised primarily of aberrant endothelial cells. COSMC plays a crucial role in blood vessel formation and is characterized as a molecular chaperone of T-synthase which catalyzes the synthesis of T antigen (Galβ1,3GalNAc). T antigen expression is associated with tumor malignancy in many cancers. However, roles of COSMC in infantile hemangioma are still unclear. In this study, immunohistochemistry showed that COSMC was upregulated in proliferating hemangiomas compared with involuted hemangiomas. Higher levels of T antigen expression were also observed in the proliferating hemangioma. Overexpression of COSMC significantly enhanced cell growth and phosphorylation of AKT and ERK in human umbilical vein endothelial cells (HUVECs). Conversely, knockdown of COSMC with siRNA inhibited endothelial cell growth. Mechanistic investigation showed that O-glycans were present on VEGFR2 and these structures were modulated by COSMC. Furthermore, VEGFR2 degradation was delayed by COSMC overexpression and facilitated by COSMC knockdown. We also showed that COSMC was able to regulate VEGF-triggered phosphorylation of VEGFR2. Our results suggest that COSMC is a novel regulator for VEGFR2 signaling in endothelial cells and dysregulation of COSMC expression may contribute to the pathogenesis of hemangioma.  相似文献   

20.
It has previously been shown that expression of human papillomavirus type 16 (HPV) E7 in epidermis causes hyperplasia and chronic inflammation, characteristics of pre-malignant lesions. Importantly, E7-expressing epidermis is strongly immune suppressed and is not rejected when transplanted onto immune competent mice. Professional antigen presenting cells are considered essential for initiation of the adaptive immune response that results in graft rejection. Langerhans cells (LC) are the only antigen presenting cells located in normal epidermis and altered phenotype and function of these cells may contribute to the immune suppressive microenvironment. Here, we show that LC are atypically activated as a direct result of E7 expression in the epidermis, and independent of the presence of lymphocytes. The number of LC was significantly increased and the LC are functionally impaired, both in migration and in antigen uptake. However when the LC were extracted from K14E7 skin and matured in vitro they were functionally competent to present and cross-present antigen, and to activate T cells. The ability of the LC to present and cross-present antigen following maturation supports retention of full functional capacity when removed from the hyperplastic skin microenvironment. As such, opportunities are afforded for the development of therapies to restore normal LC function in hyperplastic skin.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号