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81.
82.
Nimmakayalu M Major H Sheffield V Solomon DH Smith RJ Patil SR Shchelochkov OA 《American journal of medical genetics. Part A》2011,155(2):418-423
Microdeletions of the long arm of chromosome 17 are being reported with increasing frequency. Deletions of 17q22q23.2 may represent a genetically recognizable phenotype although its spectrum of genomic abnormalities, clinical manifestations, and critical regions are not fully delineated. Isolated reports and small case series suggest that deletions of 17q22q23.2 result in haploinsufficiency of dosage sensitive genes NOG, TBX2, and TBX4, which may be responsible for many aspects of the phenotype. Shared clinical features in this group of patients include microcephaly, prenatal onset growth restriction, heart defects, tracheoesophageal fistula, and esophageal atresia (TEF/EA), skeletal anomalies, and moderate to severe global developmental delay. We describe a female patient who presented with severe congenital microcephaly, thyroglossal duct cyst, sensorineural hearing loss, mild tracheomalacia, abnormal auricles, pulmonary hypertension, developmental delay, and postnatal onset growth delay. She had no TEF/EA or heart defects. Using a high density oligonucleotide microarray, we identified a microdeletion at 17q22q23.2, resulting in the heterozygous loss of several genes, including TBX2 and TBX4 but not NOG. The breakpoints did not lie within known segmental duplications. This case helps to further delineate the critical region for TEF/EA, which is likely confined to the chromosomal region proximal to 17q23.1, and suggests that genes in 17q23.1q23.2 may be associated with thyroglossal duct cysts. The role of TBX2 and TBX4 in pulmonary hypertension warrants investigation. 相似文献
83.
Denis A. Mogilenko Oleg Shpynov Prabhakar Sairam Andhey Laura Arthur Amanda Swain Ekaterina Esaulova Simone Brioschi Irina Shchukina Martina Kerndl Monika Bambouskova Zhangting Yao Anwesha Laha Konstantin Zaitsev Samantha Burdess Susan Gillfilan Sheila A. Stewart Marco Colonna Maxim N. Artyomov 《Immunity》2021,54(1):99-115.e12
84.
Oleg Y. Lyakin Konstantin P. Bryliakov Valentina N. Panchenko Nina V. Semikolenova Vladimir A. Zakharov Evgenii P. Talsi 《Macromolecular chemistry and physics.》2007,208(11):1168-1175
Reactions of 1 and 2 with MAO and MMAO were monitored by EPR. It was found that MMAO is a stronger reducing agent than MAO. 1 is more prone to reduction than 2 . The reduction of ZrIV to ZrIII seems to be the essential pathway of some zirconocene catalysts' deactivation. ZrIII species with the following proposed structures can be identified in the 1 /MMAO system: (2-PhInd)2ZrIII(iBu), (2-PhInd)2ZrIII(µ-Cl)2AliBu2, (2-PhInd)2ZrIII(µ-Cl)(iBu)AliBu2, and [(2-PhInd)2ZrIII]+[Me-MAO]−. The degree of reduction of ZrIV species determined by EPR in the catalytic system 2 /MMAO can be masked by the formation of diamagnetic ZrIII/ZrIII dimers. Addition of monomers to the 2 /MAO system promotes reduction ot the zirconium species.
85.
Distal Proctocolitis and n-3 Polyunsaturated Fatty Acids (n-3 PUFAs): The Mucosal Effect In Situ 总被引:1,自引:0,他引:1
Almallah YZ Ewen SW El-Tahir A Mowat NA Brunt PW Sinclair TS Heys SD Eremin O 《Journal of clinical immunology》2000,20(1):68-76
It has been postulated that patients with ulcerative colitis (UC) have altered reactivity of gut-associated lymphoid tissue. In such cases there is intense infiltration of the mucosa with immune competent cells and associated tissue damage. We have shown previously that the dietary supplementation with the n-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) results in significant systemic immune suppression. The aim of this study, therefore, was to evaluate the in situ effect of n-3 PUFAs on distal proctocolitis. Each patient received either fish oil extract (EPA 3.2 g, DHA 2.4 g) (n = 9) or sunflower oil (n = 9) daily in a double blind manner for six months. Monthly assessment included: (1) disease activity using clinical, sigmoidoscopic, and histological scores and (2) immunohistochemical analysis (immunoglobulins, CD profiles) of rectal biopsy specimens (before and after six months supplementation) using monoclonal antibodies and quantitative computer-assisted video image analysis. Prior to receiving supplementation, patients with proctocolitis (n = 18) showed significantly higher numbers of cells expressing CD3 (pan T cells) and HLA-DR and IgM containing cells compared with non-colitic controls (n = 8). Six months supplementation with n-3 PUFAs resulted in significant reduction in the number of cells expressing CD3 and HLA and the percentage of cells containing IgM. There was no significant change in the CD20 nor the percentage of IgG or IgA containing cells in either group of patients with procto-colitis. In patients receiving n-3 PUFA supplementation, there was improvement in the disease activity and histological scores, compared with pretreatment evaluation. This study has demonstrated both evidence of suppression of in situ immune reactivity and concurrent reduction in disease activity in patients with proctocolitis receiving n-3 PUFA supplementation. This may have important implication for therapy in patients with ulcerative colitis. 相似文献
86.
de França Juliane Santos de Sales-Neto José Marreiro Carvalho Deyse Cristina Madruga de Almeida Lima Éssia Olegário Tayná Rodrigues Mendes Rhuan Karlos Santos Lima-Junior Claudio Gabriel de Almeida Vasconcellos Mário Luiz Araújo Rodrigues-Mascarenhas Sandra 《Inflammation》2021,44(3):899-907
Inflammation - Morita-Baylis-Hillman adducts (MBHA) are synthetic molecules with several biological actions already described in the literature. It has been previously described that adduct... 相似文献
87.
Soltysinska E Thiele S Olesen SP Osadchii OE 《Pflügers Archiv : European journal of physiology》2011,462(4):529-543
It is uncertain if downregulation of β-adrenoceptor signaling pathway is promoted by an enhanced adrenergic tone at an early
stage of cardiac disease, or it develops secondary to detrimental local myocardial changes in advanced heart failure. We examined
the integrity of β-adrenoceptor signaling pathway upon chronic infusion of isoproterenol, a β-adrenoceptor agonist, at a dose
producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400 μg kg−1 h−1 over 16 days) to guinea pigs using osmotic minipumps produced no change in cardiac weights, LV internal dimensions, myocyte
cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations
from isoproterenol-treated guinea pigs exhibited attenuated responsiveness to acute β-adrenoceptor stimulation, as evidenced
by reduced LV developed pressure increase, less shortening of LV epicardial monophasic action potential and effective refractory
period, and less myocardial cyclic adenosine monophosphate elevation, in response to isoproterenol exposure, when compared
to saline-treated controls. Pharmacological responses to forskolin, an activator of the adenylate cyclase catalytic subunit,
were well preserved in isoproterenol-treated hearts. Downregulation of β-adrenoceptor-mediated effects upon chronic isoproterenol
infusion was associated with markedly reduced stimulatory G-protein α-subunit (Gsα) myocardial expression levels. No change in expression levels of β-adrenoceptors, G-protein-coupled receptor kinase 2, inhibitory
G-protein α-subunit (Giα2), and Cav1.2 and Kv7.1 ion channels was determined in isoproterenol-treated hearts. We therefore conclude that sustained adrenergic overstimulation
may promote downregulation of myocardial β-adrenoceptor-mediated effects independently of structural LV remodeling and systolic
failure, an effect attributed to β-adrenoceptor uncoupling from adenylate cyclase due to reduced Gsα-protein expression. 相似文献
88.
89.
Arvi Hakanen Teemu Siiskonen Roy P?ll?nen Antti Kosunen Asko Turunen Oleg Belyakov 《Applied radiation and isotopes》2006,64(8):864-867
Design, spectrum measurements and simulations for an alpha-particle irradiator for bystander effect and genomic instability experiments are presented. Measured alpha-particle energy spectra were used to confirm the characteristics of the source of the irradiator specified by the manufacturer of the source. The spectra were measured in vacuum with a high-resolution spectrometer and simulated with an AASI Monte Carlo code. As a next step, we simulated alpha-particle energy spectra at the target plane of the irradiator for three different source-to-target distances. In these simulations, helium was used as the medium between the source and the exit window of the irradiator; its pressure and temperature corresponded to those of the ambient air. Mean energies and full-widths at half-maximum (FWHM) were calculated for the three different helium gas tracks. 相似文献
90.
A 69-year-old man presented with gross hematuria and irritative urinary symptoms. He underwent transurethral resection of his prostate. The prostate chips revealed 70% poorly differentiated carcinoma with neuroendocrine features, initially read as small cell carcinoma, later as basal cell carcinoma. PSA at this time was 0.3. He received 4 cycles of etoposide and cisplatin. After which, rebiopsy of the prostate showed tumor consistent with poorly differentiated basal cell carcinoma. Given progression on chemotherapy, decision was made to proceed with radical prostatectomy. Metastatic workup was negative. Gross extraprostatic invasion was noted but lymph nodes were free of metastatic disease. 相似文献