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121.
Herein we report the clinicopathological features of four cases of pulmonary artery sarcoma that appeared at our institution during a period of 30 years. The patients, 2 males and 2 females, were 50–62 years old. Tumour was found in the pulmonary trunk and right pulmonary artery in all cases, in the pulmonary valve and left pulmonary artery in three of the four cases, and in the right ventricular outflow tract in one case. There was direct extension or metastases to the lungs in two cases, the heart in one case, mediastinum or lymph nodes in two cases and the pleura in one case. Ultrastructural examination in one case revealed cells with features of smooth muscle cells and myofibroblasts. Immunohistochemical examination of three cases gave the following results: vimentin and smooth muscle specific actin was positive in all three cases, desmin in one case and cytokeratin in one case. No positivity was found for Factor VIII. This and other studies indicate that histologically most pulmonary artery sarcomas are leiomyosarcomas or undifferentiated spindle cell sarcomas. Immunohistochemical and ultrastructural examinations favour an origin from myofibroblasts, probably derived from multipotent (undifferentiated) cells in the wall of the vessel. Most lesions show extensive intrathoracic growth although they rarely metastasize outside the thoracic cavity. They have a poor prognosis although some cases are currently being diagnosed during life. 相似文献
122.
123.
Reddy MV Johansson M Sturfelt G Jönsen A Gunnarsson I Svenungsson E Rantapää-Dahlqvist S Alarcón-Riquelme ME 《Genes and immunity》2005,6(8):658-662
The gene PTPN22 is located on chromosome 1p13 and encodes a protein tyrosine phosphatase called the lymphoid-specific phosphatase (Lyp). Lyp is expressed in lymphocytes, where it physically associates through its proline-rich motif (called P1) with the SH3 domain of the protein tyrosine kinase Csk, an important suppressor of the Src family of kinases Lck and Fyn, which mediate TCR signaling. Therefore, it is said that interaction between Lyp and Csk enables these effectors to inhibit T-cell activation synergistically. It was reported that a missense single nucleotide polymorphism , R620W (rs2476601), 1858C->T encodes an amino-acid change in the P1 proline-rich motif of the gene PTPN22 and is associated with SLE in North American white individuals. PTPN22 gene polymorphisms were genotyped in 571 Swedish SLE patients and 1042 healthy controls using TaqMan SNP Genotyping Assay. Differences were observed between cases and control subjects at both the allele (chi(2)=11.2895;P=0.0007,1df) and genotype (chi(2)=10.2243;P=0.0013, 1df) levels. We also found evidence of a genetic association between PTPN22 and renal disorder (chi(2)=9.5660;P=0.0019). We then analyzed if in patients with renal disorder associations with PDCD1 and PTPN22 were independent. Our data suggest that this appears to be the case although we observed some degree of interaction. 相似文献
124.
Macefield VG Johansson RS 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,152(2):143-149
Electrical stimulation of the digital nerves can cause short- and long-latency increases in electromyographic activity (EMG) of the hand muscles, but mechanical stimulation of primarily tactile afferents in the digits generally evokes only a long-latency increase in EMG. To examine whether such stimuli can elicit short-latency reflex responses, we recorded EMG over the first dorsal interosseous muscle when subjects (n=13) used the tip of the right index finger to restrain a horizontally oriented plate from moving when very brisk tangential forces were applied in the distal direction. The plate was subjected to ramp-and-hold pulling loads at two intensities (a 1-N load applied at 32 N/s or a 2-N load applied at 64 N/s) at times unpredictable to the subjects (mean interval 2 s; trial duration 500 ms). The contact surface of the manipulandum was covered with rayon—a slippery material. For each load, EMG was averaged for 128 consecutive trials with reference to the ramp onset. In all subjects, an automatic increase in grip force was triggered by the loads applied at 32 N/s; the mean onset latency of the EMG response was 59.8±0.9 (mean ± SE) ms. In seven subjects (54%) this long-latency response was preceded by a weak short-latency excitation at 34.6±2.9 ms. With the loads applied at 64 N/s, the long-latency response occurred slightly earlier (58.9±1.7 ms) and, with one exception, all subjects generated a short-latency EMG response (34.9±1.3 ms). Despite the higher background grip force that subjects adopted during the stronger loads (4.9±0.3 N vs 2.5±0.2 N), the incidence of slips was higher—the manipulandum escaped from the grasp in 37±5% of trials with the 64 N/s ramps, but in only 18±4% with the 32-N/s ramps. The deformation of the fingertip caused by the tangential load, rather than incipient or overt slips, triggered the short-latency responses because such responses occurred even when the finger pad was fixed to the manipulandum with double-sided adhesive tape so that no slips occurred. 相似文献
125.
Johansson B Axelsson P Billström R Strömbeck B Arheden K Olofsson T Cervin A Adriansson M Tanke HJ Mitelman F Fioretos T 《Genes, chromosomes & cancer》2001,30(3):261-266
Three adult de novo acute myeloid leukemias (AML M1, M2, and M4) with an isochromosome 7p are presented. No additional abnormalities were detected by G-band and multicolor, using combined binary ratio labeling, fluorescence in situ hybridization (FISH) analyses, indicating that the i(7p) was the sole, i.e., the primary, chromosomal aberration. Although the patients were elderly--68, 72, and 78 years old--they all responded very well to chemotherapy, achieving complete remission lasting more than a year. Further FISH analyses, using painting, centromeric, as well as 7q11.2-specific YAC probes, revealed that the i(7p) contained two centromeres and that the breakpoints were located in 7q11.2. Thus, the abnormality should formally be designated idic(7)(q11.2). The detailed mapping disclosed a breakpoint heterogeneity, with the breaks in 7q11.2 varying among the cases, being at least 1,310 kb apart. Furthermore, the breakpoints also differed within one of the cases, being located on both the proximal and the distal side of the most centromeric probe used. Based on our three patients, as well as on a previously reported 82-year-old patient with AML M2 and idic(7)(q11) as the only chromosomal change, we suggest that this abnormality, as the sole anomaly, is associated with AML in elderly patients who display a good response to induction chemotherapy and, hence, have a favorable prognosis. Furthermore, the heterogeneous breakpoints in 7q11.2 suggest that the important functional outcome of the idic(7)(q11.2) is the genomic imbalance incurred, i.e., gain of 7p and loss of 7q material, rather than a rearrangement of a specific gene. 相似文献
126.
Storlazzi CT Fioretos T Paulsson K Strömbeck B Lassen C Ahlgren T Juliusson G Mitelman F Rocchi M Johansson B 《Human molecular genetics》2004,13(14):1479-1485
Double minutes (dmin), the cytogenetic hallmark of genomic amplification, are found in approximately 1% of karyotypically abnormal acute myeloid leukemias (AML) and myelodysplastic syndromes (MDS). The MYC gene at 8q24 has been reported to be amplified in the majority of the cases, and generally it has been assumed that MYC is the target gene. However, only a few studies have focused on the extent of the amplicon or on the expression patterns of the amplified genes. We have studied six cases (five AML and one MDS) with MYC-containing dmin. Detailed fluorescence in situ hybridization analyses identified a common 4.3 Mb amplicon, with clustered proximal and distal breakpoints, harboring eight known genes (C8FW, NSE2, POU5FLC20, MYC, PVT1, AK093424, MGC27434 and MLZE). The corresponding region was deleted in one of the chromosome 8 homologues in five of the six cases, suggesting that the dmin originated through extra replication (or loop-formation)--excision--amplification. Northern blot analysis revealed that MYC was not overexpressed. Instead, the C8FW gene, encoding a phosphoprotein regulated by mitogenic pathways, displayed increased expression. These results exclude MYC as the target gene and indicate that overexpression of C8FW may be the functionally important consequence of 8q24 amplicons in AML and MDS. 相似文献
127.
T Jalonen S Johansson I Holopainen S S Oja P Arhem 《Acta physiologica Scandinavica》1989,136(4):611-612
128.
Virgil Percec Gabriela Zipp Gary Johansson Uwe Beginn Martin Mller 《Macromolecular chemistry and physics.》1997,198(2):265-277
Synthesis and characterization of methacrylate-monofunctionalized crown ether compounds based on derivatives of 2-hydroxymethyl-1,4,7,10,13-pentaoxacyclopentadecane and 4′-hydroxymethyl-1,4,7,10,13-pentaoxabenzocyclopentadecane is described. By differential scanning calorimetry (DSC) and thermooptical analysis (TOA) it is shown that the synthesized compounds and their sodium triflate complexes exhibit columnar mesophases. 相似文献
129.
Group A Streptococci from carriage and disease in Portugal: evolution of antimicrobial resistance and T antigenic types during 2000-2002 总被引:2,自引:0,他引:2
Pires R Rolo D Gama-Norton L Morais A Lito L Salgado MJ Johansson C Möllerberg G Henriques-Normark B Gonçalo-Marques J Santos-Sanches I 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(4):360-370
In this study, we analyzed the antimicrobial resistance properties and T antigenic types of 511 isolates collected in Lisbon district, Portugal, from throat swabs of healthy subjects (n=341), during 2000-2002 and from diverse infection sites (n=170) of outpatients and inpatients, during 1999-2002. Erythromycin resistance was higher in tonsillitis/pharyngitis (27.4%) and skin infection isolates (21.1%), than in carriage and invasive isolates (相似文献
130.
F Mertens S Heim N Mandahl B Johansson A Rydholm A Bi?rklund J Wennerberg N Jonsson F Mitelman 《Cancer Genetics and Cytogenetics》1989,39(2):227-232
Clonal chromosome abnormalities were found in short-term cultures from two epithelial skin tumors, a basal cell papilloma and a keratoacanthoma. The three-way translocation t(2;6;11)(q21;q27;p13) was the sole clonal rearrangement in the basal cell papilloma. The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter----2p13::2p11----cen----2q37: :5q33----5qter),der(2) (:2p13----cen----2q37::6q23----6qter),der(5)t(2; 7;5)(q37;q11;q33),der(6) (6pter----cen----6q23::2p13----2pter),der(7)t(2; 7;5)(q37;q11;q33), del(13)(q11q14). In addition, several nonclonal structural changes were seen in both tumors. 相似文献