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1.
Methodichlorophen was given to 26 patients with terminal malignant disease. Eight patients received adequate doses, and five of them showed objective evidence of tumour regression while three failed to respond. Those who responded included four out of five patients with lung cancer (three with squamous-cell carcinoma and one with oat-cell carcinoma) and a patient with hypernephroma. Two patients with testicular teratomas and one with acute myeloid leukemia failed to respond. The drug may be given safely by mouth to outpatients if certain precautions are taken.  相似文献   

2.
By virtue of meiotic cell division, primordial germ cells with heterozygous alleles develop into postmeiotic germ cells with homozygous alleles. Female and male germ cells may develop tumors - so-called teratomas - with a unique co-existence of a variety of histological elements from all three embryonic germ layers. In particular, mature teratomas consist exclusively of developmentally mature tissues whereas immature teratomas contain variable amounts of mature and immature tissues. In this study, we report genetic analysis of individual tissue components from mature and immature teratomas. The majority of mature teratomas showed consistent and concordant homozygous alleles in all selectively procured tissue components. In a small subset of mature teratomas, we observed discordant homozygous alleles. In contrast, immature teratomatous tissue revealed a heterozygous genotype. Remarkably, mature tissue components within immature teratoma revealed homozygosity. The findings suggest that immature teratomas and at least a subset of mature teratomas may originate from premeiotic cells, and implicate that meiosis may be required for differentiation into mature tissues.  相似文献   

3.
Tobacco shooty or rooty teratomas and hairy roots were induced by Agrobacterium tumefaciens (pGV 3845), A. tumefaciens (pGV 3304) and A. rhizogenes (pRi 8196), respectively. The tobacco alkaloids, nicotine, nornicotine and anatabine, were produced in hairy roots and in rooty teratomas but not in shooty teratomas. However, the shooty teratomas have the ability to accumulate the alkaloids and to biotransform nicotine to nornicotine. These were established by co-culture experiments incubating hairy roots and shooty teratomas in a same dish and by biotransformation experiments with shooty teratomas.  相似文献   

4.
Origin of teratomas and twins   总被引:10,自引:0,他引:10  
Summary Probabilities are given for three modes of origins of teratomas and for five possible modes of origins of twins. Besides testing for monoluteal dispermic twins, these probabilities enable centromere mapping. Trisomy and triploidy arising through nondisjunction give the same information.  相似文献   

5.
The cell of origin of the five subtypes (I-V) of germ cell tumors (GCTs) are assumed to be germ cells from different maturation stages. This is (potentially) reflected in their methylation status as fetal maturing primordial germ cells are globally demethylated during migration from the yolk sac to the gonad. Imprinted regions are erased in the gonad and later become uniparentally imprinted according to fetal sex. Here, 91 GCTs (type I-IV) and four cell lines were profiled (Illumina’s HumanMethylation450BeadChip). Data was pre-processed controlling for cross hybridization, SNPs, detection rate, probe-type bias and batch effects. The annotation was extended, covering snRNAs/microRNAs, repeat elements and imprinted regions. A Hidden Markov Model-based genome segmentation was devised to identify differentially methylated genomic regions. Methylation profiles allowed for separation of clusters of non-seminomas (type II), seminomas/dysgerminomas (type II), spermatocytic seminomas (type III) and teratomas/dermoid cysts (type I/IV). The seminomas, dysgerminomas and spermatocytic seminomas were globally hypomethylated, in line with previous reports and their demethylated precursor. Differential methylation and imprinting status between subtypes reflected their presumed cell of origin. Ovarian type I teratomas and dermoid cysts showed (partial) sex specific uniparental maternal imprinting. The spermatocytic seminomas showed uniparental paternal imprinting while testicular teratomas exhibited partial imprinting erasure. Somatic imprinting in type II GCTs might indicate a cell of origin after global demethylation but before imprinting erasure. This is earlier than previously described, but agrees with the totipotent/embryonic stem cell like potential of type II GCTs and their rare extra-gonadal localization. The results support the common origin of the type I teratomas and show strong similarity between ovarian type I teratomas and dermoid cysts. In conclusion, we identified specific and global methylation differences between GCT subtypes, providing insight into their developmental timing and underlying developmental biology. Data and extended annotation are deposited at GEO (GSE58538 and GPL18809).  相似文献   

6.
Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of β1 integrin during teratoma formation, we compared teratomas induced by normal and β1-null ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, β1-null ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of β1-null teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in β1-null teratomas. Basement membranes were present but with irregular shape and detached from the cell surface.

Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell–derived endothelial cells. In contrast, β1-null teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although β1- deficient endothelial cells were absent in teratomas, β1-null ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in β1-null embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in β1-null embryoid bodies.

  相似文献   

7.
One hundred and two benign, mature ovarian teratomas and two immature, malignant teratomas were karyotyped and scored for centromeric heteromorphisms as part of an ongoing project to determine the chromosomal karyotype and the genetic origin of ovarian teratomas and to assess their utility for gene-centromere mapping. Karyotypic analysis of the benign cases revealed 95 46,XX teratomas and 7 chromosomally abnormal teratomas (47,XXX, 47,XX,+8 [two cases], 47,XX,+15, 48,XX,+7,+12 91,XXXX,-13 [mosaic], 47,XX,-15,+21,+mar). Our study reports on the first cases of tetraploidy and structural rearrangement in benign ovarian teratomas. The two immature cases had modal chromosome numbers of 78 and 49. Centromeric heteromorphisms that were heterozygous in the host were homozygous in 65.2% (n = 58) of the benign teratomas and heterozygous in the remaining 34.8% (n = 31). Chromosome 13 heteromorphisms were the most informative, with 72.7% heterozygosity in hosts. The cytogenetic data indicate that 65% of teratomas are derived from a single germ cell after meiosis I and failure of meiosis II (type II) or endoreduplication of a mature ovum (type III); 35% arise by failure of meiosis I (type I) or mitotic division of premeiotic germ cells (type IV).  相似文献   

8.
Atypical teratomas of the pineal were studied pathologically and clinically, and five illustrative cases are described. The results of three postmortem examinations are available, while two of the patients are living, one leading a normal life. Pathological verification revealed that two had suprasellar “ectopic” pinealomas. One neoplasm was located in the pineal (collicular) region. The histology of the tumours was identical, consisting of small cells resembling lymphocytes and large cells with prominent nucleoli and mitoses. This feature plus the midline location led to adoption of the term “atypical teratoma”. Patients with collicular pinealomas presented with headache, vomiting, papilledema, Parinaud''s syndrome and, rarely, nystagmus retractorius. Diabetes insipidus, visual difficulty and hypopituitarism were characteristic features in those with suprasellar neoplasms. Treatment of collicular pinealoma has consisted of the use of a palliative shunt followed by a course of radiation. Chiasmal decompression and radiation have produced favourable results in patients with suprasellar pinealoma.  相似文献   

9.
Chromosomal heteromorphisms and DNA polymorphisms have been utilized to identify the mechanisms that lead to formation of human ovarian teratomas and to construct a gene-centromere map of chromosome 1 by using those teratomas that arise by meiotic nondisjunction. Of 61 genetically informative ovarian teratomas, 21.3% arose by nondisjunction at meiosis I, and 39.3% arose by meiosis II nondisjunction. Eight polymorphic marker loci on chromosome 1p and one marker on 1q were used to estimate a gene-centromere map. The results show clear linkage of the most proximal 1p marker (NRAS) and the most proximal 1q marker (D1S61) to the centromere at a distance of 14 cM and 20 cM, respectively. Estimated gene-centromere distances suggest that, while recombination occurs normally in ovarian teratomas arising by meiosis II errors, ovarian teratomas arising by meiosis I nondisjunction have altered patterns of recombination. Furthermore, the estimated map demonstrates clear evidence of chiasma interference. Our results suggest that ovarian teratomas can provide a rapid method for mapping genes relative to the centromere.  相似文献   

10.
OBJECTIVE: To quantify immunocompetent cell (IC) density for different testicular tumors and antibodies and to verify if the results of the comparisons depend on the antibody used. STUDY DESIGN: T-lymphocytes were studied with CD3 and UCHL1 antibodies and macrophages with MAC387 and CD68 in 43 patients with seminomas, mature teratomas, immature teratomas and embryonal carcinomas of the testis. Counts were expressed as number of IC per square millimeter. RESULTS: Use of different antibodies produced significant differences in the IC cell number; moreover, in the case of macrophages, the tumor type sequence by increasing cell number was different according to the antibody used. CONCLUSION: These results suggest the existence of a statistical interaction between the type of tumor and antibody.  相似文献   

11.
Most malignant testicular neoplasms are of germ cell origin. They are divided into five basic types: seminomas, embryonal carcinomas, teratocarcinomas, adult teratomas and choriocarcinomas. Clinically they may present as an enlarging testicular mass, or with symptoms resulting from metastases or hormonal secretions. The treatment of choice for patients with seminomas is orchiectomy, followed by radiation therapy. This combination results in an 80 to 100 percent five-year survival rate in patients with nonmetastatic or locally metastatic disease. The treatment of nonseminomatous germ cell tumors is more controversial. An aggressive approach, however, with retroperitoneal lymph node dissection and adjuvant chemotherapy has resulted in an overall 78 percent survival rate. Several placental and fetal proteins are secreted by these tumors. Two of these, human chorionic gonadotropin and alpha-fetoprotein, have been shown to be useful for the diagnosis of these neoplasms, for following the disease activity during therapy and for detection of recurrences.  相似文献   

12.
 The developmental potential of parthenogenetic embryonic stem (P-ES) cells was studied in teratomas and mouse chimaeras. Teratomas derived from P-ES cells contained a mixture of tissue types with variable proportions of specific tissues. Three of the eight P-ES cell lines analysed showed high proportions of striated muscle in teratomas, similar to teratomas from normal embryos or ES cell lines derived from fertilised embryos (F-ES cells). Our study also revealed that one P-ES cell line showed little lineage restriction in injection chimaeras. Descendants of the P-ES cells contributed to most tissues of chimaeric fetuses in patterns similar to F-ES cells. Normal colonisation of muscle, liver and pancreas was found in adult chimaeras. P-ES cells also showed similar haematopoietic differentiation and maturation as F-ES cells. However, extensive P-ES cell contribution was associated with a reduction in body size. These findings suggest that, while P-ES cells display more extensive developmental potential than the cells of parthenogenetic embryos from which they were derived, they only retained properties related to the presence of the maternal genome. To elucidate the molecular basis for the lack of lineage restriction during in vivo differentiation, the expression of four imprinted genes, H19, Igf2r, Igf2 and Snrpn was compared among five P-ES and two F-ES cell lines. Expression levels of these genes varied among the different ES cell lines, both in undifferentiated ES cells and in embryoid bodies.  相似文献   

13.
本文报道了致瘤农杆菌(Agrobacterium lume/aciens)的T(?)菌株对分属于五大类型的41个品种的栽培种花生致瘤实验结果。在41个品种中的6个品种上诱发了畸胎瘤。在无激素的MS培养基上诱发冠瘿瘤产生了愈伤组织。瘤组织、愈伤组织,畸胎瘤上幼苗的茎和叶均含有胭脂碱。  相似文献   

14.
Ovarian teratomas are tumors that arise from female germ cells and are often a mixture of immature embryonal carcinoma cells and mature embryonic cells. Tissues derived from all three primary embryonic lineages (ectoderm, mesoderm, and endoderm) are typically found in the mature elements of a teratoma. In the case of the transgenic mouse line TG.KD, created with an imprinted transgene construct, malignant ovarian teratomas of a mixed germ cell tumor morphology occur in 15–20% of hemizygous female carriers of the transgene. The tumors frequently metastasize and can result in death of the mouse. Genetic analysis indicates that the tumors are associated with the transgene's integration site. Inbred FVB/N and female mice of other transgenic lines, also created in the inbred FVB/N strain with the same DNA construct as TG.KD, do not develop teratomas. In addition to teratomas, the integration of the transgene on Chromosome (Chr) 8 is associated with a perinatal lethality in homozygous transgenic carriers. The hemizygous genotypes of the teratomas suggest that they arise from early germ cells, prior to the completion of meiosis I. Received: 31 August 1995 / Accepted: 3 November 1995  相似文献   

15.
The potential for the formation of teratomas or other neoplasms is a major safety roadblock to clinical application of pluripotent stem cell therapies. Preclinical assessment of the risk of tumor formation in this context poses considerable scientific and regulatory challenges, especially because animal xenograft models may not properly reflect the long-term tumorigenic potential of human cells. A better understanding of the biology of spontaneously occurring teratomas and related tumors in humans can help to guide efforts to assess and minimize the potential hazards of embryonic stem cell or induced pluripotent stem cell therapeutics. Here we review the features of teratomas derived experimentally from human pluripotent stem cells and argue that they most closely resemble spontaneous benign teratomas that occur early in both mouse and human life. The natural history and pathology of these spontaneously occurring teratomas provide important clues for preclinical safety assessment and patient monitoring in trials of stem cell therapies.  相似文献   

16.
Many mutations of the murine genome are recessive embryonic lethals precluding phenotype analysis at subsequent stages of development. This is true for embryos genetically lacking either N-cadherin or N- and P-cadherin. To circumvent this, we have generated pluripotent embryonal stem (ES) cells of the same genotype in vitro and differentiated them in vivo in the form of teratomas. All of the ES cells isolated in this study had a normal ES cell morphology in vitro and were able to generate teratomas. Histological analysis revealed that some differentiation and histogenesis had occurred within the teratomas. Epithelial formation was, for example, unaffected in all cadherin null cells. Surprisingly, however, the differentiation of cells lacking both N- and P-cadherin was, in general, even more pronounced both quantitatively and qualitatively. Tumours lacking either N- cadherin or N- and P-cadherin contained more striated muscle (apparently cardiac muscle) than heterozygote controls, and this was most strikingly conspicuous in teratomas from N- and P-cadherin null cells. This more pronounced differentiation was not seen for all tissues, however, as structures with a simple neural tube-like morphology were never found in teratomas lacking both N- and P-cadherin and organoid-like structures were rare in Ncad-/-tissue.  相似文献   

17.
Here, we present evidence that the tumor-like growth of mouse embryonic stem cells (mESCs) is suppressed by short-term serum-free culture, which is reversed by pharmacological inhibition of Gsk3β. Mouse ESCs maintained under standard conditions using fetal bovine serum (FBS) were cultured in a uniquely formulated chemically-defined serum-free (CDSF) medium, namely ESF7, for three passages before being subcutaneously transplanted into immunocompromised mice. Surprisingly, the mESCs failed to produce teratomas for up to six months, whereas mESCs maintained under standard conditions generated well-developed teratomas in five weeks. Mouse ESCs cultured under CDSF conditions maintained the expression of Oct3/4, Nanog, Sox2 and SSEA1, and differentiated into germ cells in vivo. In addition, when mESCs were cultured under CDSF conditions supplemented with FBS, or when the cells were cultured under CDSF conditions followed by standard culture conditions, they consistently developed into teratomas. Thus, these results validate that the pluripotency of mESCs was not compromised by CDSF conditions. Mouse ESCs cultured under CDSF conditions proliferated significantly more slowly than mESCs cultured under standard conditions, and were reminiscent of Eras-null mESCs. In fact, their slower proliferation was accompanied by the downregulation of Eras and c-Myc, which regulate the tumor-like growth of mESCs. Remarkably, when mESCs were cultured under CDSF conditions supplemented with a pharmacological inhibitor of Gsk3β, they efficiently proliferated and developed into teratomas without upregulation of Eras and c-Myc, whereas mESCs cultured under standard conditions expressed Eras and c-Myc. Although the role of Gsk3β in the self-renewal of ESCs has been established, it is suggested with these data that Gsk3β governs the tumor-like growth of mESCs by means of a mechanism different from the one to support the pluripotency of ESCs.  相似文献   

18.
N. Gupta, A. Rajwanshi, L. K. Dhaliwal, N. Khandelwal, P. Dey, R. Srinivasan and R. Nijhawan
Fine needle aspiration cytology in ovarian lesions: an institutional experience of 584 cases Objective: To assess the diagnostic value of fine needle aspiration cytology (FNAC) in ovarian lesions. Methods: This was a retrospective study of ultrasound‐guided (US) FNAC of 584 ovarian lesions from January 1998 to July 2010. The lesions were categorized into non‐neoplastic lesions, neoplastic lesions and inadequate aspirates. The results were compared with the corresponding histopathology whenever available. Results: Of the 584 lesions, 180 (30.8%) were reported as non‐neoplastic (48 non‐specific inflammation, 11 tuberculosis, 63 functional cysts and 58 endometriotic cysts), 249 (42.6%) as neoplastic (81 benign lesions/tumours and 168 malignant) and 155 (26.5%) as inadequate. Based on the subsequent histopathology, which was available in 121 (20.7%), the cases were divided into those that were concordant and discordant. Concordant cases comprised 92/121 (76%), including 28 non‐neoplastic lesions (seven non‐specific inflammation, nine functional cysts and 12 endometriotic cysts), 42 surface epithelial tumours (13 benign and 29 malignant), 10 germ cell tumours (five mature cystic teratomas and five mixed germ cell tumours), seven sex‐cord stromal tumours (three granulosa cell tumours, one sclerosing stromal tumour, one strümal leutoma, one Sertoli Leydig cell tumour and one malignant Sertoli cell tumour) and five miscellaneous lesions (one plasma cell tumour, two leiomyosarcomas and two cases of necrosis). Discordant cases comprised 29/121 (24%) (21were inconclusive or inadequate on cytology), including four endometriotic cysts, 14 surface epithelial tumours (one cystadenofibroma, one borderline mucinous tumour and 12 carcinomas), five germ cell tumours (two immature teratomas and three mature cystic teratomas), two thecomas, one fibroma, one sclerosing stromal tumour, one fibrosarcoma and one myxoma. FNAC sensitivity for a diagnosis of malignancy was 85.7%, specificity 98.0%, positive predictive value 97.7%, negative predictive value 87.7% and accuracy 92.0%, if 21 inconclusive/inadequate FNACs were excluded; with the latter taken as false negatives, sensitivity was 73.7% and accuracy 76.0%. Conclusion: FNAC has a high specificity for diagnosis of ovarian/adnexal lesions but greater experience is required for the accurate subtyping of neoplasms and sensitivity is limited by inconclusive/inadequate results.  相似文献   

19.
In an attempt to verify the possibility that yolk sac-derived rat teratomas may be of germ cell origin, pregnant rats were treated with Busulphan. This drug, which is known to destroy the germ cells during their migratory phase, led to the complete absence of these cells in the gonads. However, Busulphan did not influence the number or the morphology of the yolk sacderived teratomas. Therefore it is concluded that these teratomas do not arise from germ cells.  相似文献   

20.
In this report we detail two congenital intracranial immature teratomas, noteworthy for their massive intracranial growth and extension through the skull with compromise of neck structures. Cytogenetic studies were done in both cases on the fetuses and their tumors and are the first in the literature. Few previously reported congenital intracranial teratomas have been described with neck extension. In both cases, polyhydramnios was detected by prenatal ultrasonography and was possibly caused by the laryngoesophageal and/or brainstem distortion by neoplasm. Possible reasons for such excessive, unchecked growth of teratomas in the fetal period are discussed.  相似文献   

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