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11.
Genetic changes in neoplasms arising in congenital melanocytic nevi: differences between nodular proliferations and melanomas 总被引:3,自引:0,他引:3 下载免费PDF全文
Bastian BC Xiong J Frieden IJ Williams ML Chou P Busam K Pinkel D LeBoit PE 《The American journal of pathology》2002,161(4):1163-1169
Large congenital melanocytic nevi (CMN) are at an increased risk of developing melanoma. Several forms of secondary proliferations can arise in congenital nevi on rare occasions. Although some of these closely resemble melanoma both clinically and histologically, metastasis is rare. We used comparative genomic hybridization to analyze chromosomal aberrations in different types of proliferations arising in CMN and compared them to typical congenital nevi, clear-cut melanomas arising in congenital nevi, as well as primary cutaneous melanomas that were not associated with a CMN. Cases of CMN and CMN with secondary proliferations were assigned to six groups according to the predominant histological pattern: group I, bland congenital nevi (n = 6); group II, congenital nevi with foci of increased cellularity (n = 4); group III, CMN with a proliferation simulating superficial spreading melanoma in situ (n = 3); group IV, CMN with a proliferation simulating nodular melanoma (n = 9); group V, proliferating neurocristic hamartoma (n = 1); and group VI, melanoma arising in congenital nevus (n = 6). No aberrations were found in groups I to III, whereas seven of nine cases of group IV, and one of one case of group V, showed aberrations. In group IV six of seven cases with aberrations (86%) showed numerical aberrations of whole chromosomes exclusively. This pattern differed significantly from the findings in melanoma that arose within CMN (n = 6), group VI, or independent of CMN (n = 122) in which only 5% showed numerical changes only. The single case in group V showed aberrations similar to melanoma. The finding of frequent numerical chromosomal aberrations in atypical nodular proliferations arising in CMN identifies these as clonal neoplasms with a genomic instability consistent with a mitotic spindle checkpoint defect. This difference compared to the aberration pattern found in melanoma might explain their more benign clinical behavior and may be of diagnostic value in ambiguous cases. 相似文献
12.
The terminology describing congenital vascular birthmarks has been a source of confusion in the medical literature. Mulliken and Glowacki [1982: Plas. Recons. Surg. 69:412-422] published a biologic classification system which has become the most widely accepted framework for classifying vascular birthmarks and is accepted as the official classification schema by the International Society for the Study of Vascular Anomalies (ISSVA). In this study, we evaluate the current nosology of vascular birthmarks used in standard medical genetics reference texts compared with the accepted Mulliken ISSVA framework. In five sources examined, a variety of terms were used to describe congenital vascular anomalies. The degree of agreement with accepted ISSVA classification varied both within and among texts, with agreement as low as 22% and as high as 75%. In all texts, hemangioma was the most commonly used term, appearing 79 times. Use of the term "hemangioma" had the lowest rate of agreement with the ISSVA classification criteria, with agreement in 23% of citations. The terms "vascular malformation" and "port-wine stain" were used less frequently, but with a much higher degree of agreement with the ISSVA classification: 82% and 66%, respectively. These results establish that nosologic confusion is widespread even in standard genetic reference texts. In particular, the term "hemangioma" is used imprecisely. The ISSVA classification system provides an extremely useful framework for geneticists to classify vascular birthmarks in their evaluation of infants and children with vascular anomalies in order to provide more accurate evaluation, prognosis, and genetic counseling. 相似文献
13.
Antti Hervonen Ilona Linnoila Virginia M. Pickel Pauli Helén Markku Pelto-Huikko Hannu Alho Richard J. Miller 《Neuroscience》1981,6(3):323-330
Both [Leu5]- and [Met5]-enkephalin have been localized immunohistochemically in nerve fibres and in small, intensely fluorescent cells of adult human sympathetic ganglia. The nerve fibres showing enkephalin-like immunoreactivity formed a network varying in density around the sympathetic neurons, some being closely related to the perikarya. No labelled neuronal cell bodies were found. No structures within the ganglion were labelled after reaction with antibodies to vasoactive intestinal polypeptide, adrenocorticotrophin or substance P. No differences between the distributions of [Leu5]-and [Met5]-enkephalin-like immunoreactivities were found.The physiological roles of enkephalins are still unknown, but it is possible that they might act as neurotransmitters or neuromodulators in the human sympathetic nervous system. 相似文献
14.
This study investigated the relationship between theory of mind (ToM) deficits and visual perception in patients with schizophrenia (N=52; 17 remitted and unmedicated) compared with healthy controls (N=30). ToM was assessed with the Eyes Test, which asked participants to choose which of 4 words best described the mental state of a person whose eyes were depicted in a photograph. Visual perception was evaluated with form and motion coherence threshold measurements. Results revealed that patients with schizophrenia (both remitted and nonremitted) showed deficits on the Eyes Test and the motion coherence task. ToM dysfunctions were associated with higher motion coherence thresholds and more severe negative symptoms. This suggests that ToM deficits are related to motion perception dysfunctions, which indicates a possible role of motion-sensitive areas in the pathophysiology of schizophrenia. 相似文献
15.
Ewa Ba?kowiec-Iskra Iwona Kurkowska-Jastrzebska Ilona Joniec Agnieszka Ciesielska Anna Cz?onkowska Andrzej Cz?onkowski 《Acta neurobiologiae experimentalis》2007,67(4):379-388
Many data suggest involvement of inflammation in neurodegeneration. However, the exact mechanisms of this cooperation are poorly understood. We have previously shown that induction of inflammatory reaction, both before and after injury of the striatum, affects regeneration of dopaminergic neurons. In the present research we studied the role of inflammatory reaction in non-injured striatum. We used myelin oligodendrocyte glycoprotein (MOG) 35-55 in complete Freund's adjuvant (CFA) to elicit experimental autoimmune encephalomyelitis (EAE) mice model. As determined by HPLC, striatal dopamine (DA) and serotonin levels in mice treated with either MOG 35-55 in CFA or CFA alone were significantly higher compared to vehicle-treated controls on 13th day after induction. The ratio of homovanilic acid/dopamine (HVA/DA) and 3, 4 dihydroxyphenylacetic acid/dopamine (DOPAC/DA) were significantly lower in the MOG and CFA groups on 13th day, indicating decreased DA metabolism. Noradrenaline (NA) concentration did not differ between groups. Moreover, the striatal mRNA IL-1beta and TNF-alpha levels were elevated during induction phase of EAE in both groups, as determined by RT-PCR. Our data indicate regulatory connection between dopaminergic and immune systems. 相似文献
16.
We have previously defined four murine CD4+ peripheral T cell subsets, fractions (Fr.) I – IV, based on expression of the 6C10 and 3G11 determinants (Hayakawa, K. and Hardy, R. R., J. Exp. Med. 1988. 168: 1825). These subsets also show distinctive levels of other cell surface markers: the two minor subsets, Fr. III and Fr. IV, are both CD45RBlow/-, L-selectin (Mel-14)? and CD44hi, characteristic of secondary T cells. The patterns and levels of cytokine production by individual cells in each subset were determined by bioassay for interleukin (IL)-2/IL-4 or IL-4/interferon (IFN)-γ production after anti-CD3 stimulation. Our data revealed that these four phenotypically defined subsets largely coincide with clusters of cells showing uniform distinctive cytokine profiles, i.e. IL-2+/IFN-γ?/IL-4? (Fr. I and Fr. II, L-selectin+), IL-2+/IFN-γ+/IL-4+ (Fr. III, L-selectin?), and IL-2?/IFN-γlow/-/IL-4+ (Fr. IV, L-selectin?). Besides these subsets, an L-selectin-negative cell subfraction within Fr. II appears to represent a transitional population between the IL-2+/IFN-γ?/IL-4? stage and the IL-2+/IFN-γ+/IL-4+ stage. Taken together, these results demonstrate the presence of two IL-4+ secondary T cell subsets with distinct cytokine production patterns, and show that the majority of IL-4+ cells found in healthy adult laboratory mice co-produce IFN-γ, and thus are not typical T helper type 2 cells. 相似文献
17.
Murielle Jacquet‐Smailovic Cyril Tarquinio Franois Alla Ilona Denis Amanda Kirche Camille Tarquinio Marie‐Jo Brennstuhl 《Journal of traumatic stress》2021,34(1):190-199
The objective of the present review is to provide an overview of existing research that has reported on the association between posttraumatic stress disorder (PTSD) and ischemic heart disease. Specific focus is given to the incidence of PTSD following myocardial infarction (MI). A systematic review using Preferred Reporting Items for Systematic reviews and Meta‐Analysis (PRISMA) guidelines was performed by searching four bibliographic databases: PubMed, PsychINFO, ScienceDirect, and ProQuest Dissertations and Theses. A total of 39 articles were included in this literature review. The results of these studies suggest that the occurrence of an acute cardiac event is likely to contribute to the development of PTSD. Not only is this type of psychiatric disorder associated with significant suffering and impaired quality of life, but it is also a predictor of an increased risk of recurrent adverse cardiovascular events and mortality. Screening, assessment, and treatment of PTSD and posttraumatic stress symptoms following a major cardiac event are critical for offsetting potential deleterious psychological and physical consequences. 相似文献
18.
19.
The carboxy-terminal domain of polymerase gene of Rous sarcoma virus was cloned into an expression vector under the control oflac regulatory elements, resulting in the plasmid pMF1413. Upon isopropyl--D-thiogalactopyranoside induction, viral integration (IN) protein was expressed in large quantity inEscherichia coli. The expressed recombinant protein was prepurified by successive washing of the bacterial pellet with 0.1 M NaCl and detergents. Further purification was performed in high yield by standard chromatography methods. The purified enzyme revealed selective DNA cleaving activity on supercoiled plasmid with the LTR-LTR junction fragment. The reaction was metal ion dependent, with a preference for Mn2+ over Mg2+, and showed substrate specificity at 1 mM MnCl2. 相似文献
20.
Ilona Kryspin S rensen Eva Kristiansen Alicja Mortensen Gert M. Nicolaisen Jolanda A. H. Wijnands Henk J. van Kranen Coen F. van Kreijl 《Cancer letters》1998,130(1-2):217-225
Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in ApcMin mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice. 相似文献