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Annika?E?StenbergEmail author Lisskulla?Sylvén Carl?GM?Magnusson Malou?Hultcrantz 《Journal of negative results in biomedicine》2004,3(1):6
Disturbances in the immune system has been described in Turner syndrome, with an association to low levels of IgG and IgM
and decreased levels of T- and B-lymphocytes. Also different autoimmune diseases have been connected to Turner syndrome (45,
X), thyroiditis being the most common. 相似文献
13.
A point mutation in the 5' splice site of the dystrophin gene first intron responsible for X-linked dilated cardiomyopathy 总被引:3,自引:4,他引:3
Milasin J; Muntoni F; Severini GM; Bartoloni L; Vatta M; Krajinovic M; Mateddu A; Angelini C; Camerini F; Falaschi A; Mestroni L; Giacca M 《Human molecular genetics》1996,5(1):73-79
X-linked dilated cardiomyopathy (XLDC) is a familial heart disease
presenting in young males as a rapidly progressive congestive heart
failure, without clinical signs of skeletal myopathy. This condition has
recently been linked to the dystrophin gene in some families and deletions
encompassing the genomic region coding for the first muscle exon have been
detected. In order to identify the defect responsible for this disease at
the molecular level and to understand the reasons for the selective heart
involvement, a family with a severe form of XLDC was studied. In the
affected members, no deletions of the dystrophin gene were observed.
Analysis of the muscle promoter, first exon and intron regions revealed the
presence of a single point mutation at the first exon-intron boundary,
inactivating the universally conserved 5' splice site consensus sequence of
the first intron. This mutation introduced a new restriction site for MseI,
which cosegregates with the disease in the analyzed family. Expression of
the major dystrophin mRNA isoforms (from the muscle-, brain- and Purkinje
cell-promoters) was completely abolished in the myocardium, while the
brain- and Purkinje cell- (but not the muscle-) isoforms were detectable in
the skeletal muscle. Immunocytochemical studies with anti- dystrophin
antibodies showed that the protein was reduced in quantity but normally
distributed in the skeletal muscle, while it was undetectable in the
cardiac muscle. These findings indicate that expression of the muscle
dystrophin isoform is critical for myocardial function and suggest that
selective heart involvement in dystrophin- linked dilated cardiomyopathy is
related to the absence, in the heart, of a compensatory expression of
dystrophin from alternative promoters.
相似文献
14.
We have examined the specificity of binding of A/NWS/33 hemagglutinin (HA), exploring the effects of fucosylation, changing the Gal-GlcNAc linkage between the second and third sugars, and binding affinity for alpha2,8-linked sialic acid. The HA of A/NWS/33(HA)-Tokyo/67(NA) (NWS-Tok, H1N2) virus binds to 3'-linked sialyllactose with 10-fold higher affinity than 3' sialyllactosamine and 3-fold higher affinity than 6' sialyllactosamine. The P227H mutation in A/NWS/33(P227H)(HA)-A/Memphis/31/98(NA) (NWS-Mem/98, H1N2) results in sevenfold lower affinity for 3' sialyllactose, but binding to 6' sialyllactosamine is unchanged. The apparent switch from 3' to 6' specificity is solely due to a loss of Siaalpha2,3 binding. Fucosylation of the third sugar and changing the linkage between second and third sugars had little effect on binding by NWS-Tok, but marked effects on A/NWS/33(P227H)(HA)-tern/Australia/G70c/75(NA) (NWS-G70c, H1N9) and NWS-Mem/98. NWS-Tok, NWS-G70c, and NWS-Mem/98 bind to alpha2,8-bisialic acid with high affinity. NWS-Mem/98 can also bind to alpha2,8-trisialic acid, but with lower affinity. Together, these data show that alpha2,8-linked sialic acid, fucosylation of the third sugar, and linkage between the second and third sugars could play important roles in allowing efficient virus binding to its host cell. The finding that influenza viruses have the potential to bind to alpha2,8-linked sialic acid is a new influenza virus-receptor interaction pathway. 相似文献
15.
The hemagglutinin (HA) of influenza viruses initiates infection by binding to sialic acid on the cell surface via alpha2,6 (human) or alpha2,3 (avian) linkage. The influenza neuraminidase (NA) can cleave both alpha2,3- and alpha2,6-linked sialic acids, but all influenza NAs have a marked preference for the non-human alpha2,3 linkage. Recent H3N2 influenza viruses have lost the ability to agglutinate chicken red blood cells. To determine if changes in HA specificity or affinity correlate with NA specificity or activity, we examined red cell binding and elution of a series of H3N2 viruses. We found that the NA activity of many influenza viruses does not release binding by their HA. In some egg-adapted strains, lack of elution correlates with low levels of viral NA activity, and these elute rapidly when bacterial NA is added. However, a Fujian-like virus, A/Oklahoma/323/03, does not elute by its own NA or with Vibrio cholerae sialidase, and it binds to red cells pre-treated with V. cholerae sialidase. It elutes after addition of the broad specificity Micromonospora viridifaciens sialidase. Human glycophorin inhibits A/Oklahoma/323/03 hemagglutination 6-fold better than fetuin. We conclude that specific forms of sialic acid are used as receptor by recent human H3N2 influenza viruses, perhaps involving branched alpha2,6 sialic acid or alpha2,8 sialic acid structures on O-linked carbohydrates. The virus itself has no O-linked glycans, so even though the NA is not able to cleave receptors on cells, the viruses will not self-aggregate. It will be important to monitor efficacy of neuraminidase inhibitors in case there are NA-resistant receptors in the human respiratory tract that allow the viruses to be less dependent on NA activity. 相似文献
16.
犬21只,经左冠脉内注射麦角新硷诱发冠脉痉挛后随机静滴生理盐水(对照组)或等量盐水溶的巯甲丙脯酸(治疗组),观察1小时。心电图显示治疗组的异常ST段下降和严重室性心律失常明显少于对照组;冠脉造影显示治疗组痉挛血管支数及狭窄程度均少于和轻于对照组;左室造影和超声心电图显示治疗组的左室收缩末和舒张末容积小于对照组,EF值或△D大于对照组,AA/EA小于对照组;血流动力学参数表明治疗组左室收缩压,平均肺 相似文献
17.
18.
Eva M. Hoefnagels Lucas Weerheijm Angelique GM Witteveen Jan-Willem K Louwerens Noel Keijsers 《Foot and Ankle Surgery》2021,27(5):543-549
BackgroundThe aetiology of chronic therapy resistant plantar fasciitis (CTRPF) is multifactorial with more focus in recent times on the gastroc-soleus complex. This study evaluates the effect of lengthening the gastrocnemius muscle in CTRPF.MethodsAll patients with CRTPF complaints for at least one year underwent the same standard conservative treatment prior to surgery. 32 patients failed this treatment and underwent gastrocnemius recession. Silfverskiöld test, questionnaires and plantar pressure measurements were obtained at 5 visits.ResultsOne year follow up showed a significantly increase in dorsiflexion of the ankle (16 degrees), a decrease in VAS; 78 (SD: 19) to 20 (SD: 24) and significant improved functional scores. Plantar pressure measurements showed an increase of pressure under the medial proximal part of the midfoot and the 1 st metatarsal and a decrease under the hallux.ConclusionsA gastrocnemius recession results in a significant gain in dorsiflexion, altered loading of the foot and good clinical outcome in patients with CTRPF.Level of EvidenceLevel 2 相似文献
19.
飞行员不成熟防御机制与心理健康、
个性、生活事件、社会支持的相关性研究 总被引:5,自引:0,他引:5
【Abstract】Objective 《中国行为医学科学》1999,8(4):0
目的 探讨飞行员心理防御机制与心理社会因素的相关性。方法 对312 例飞行员进行防御方式问卷,卡特尔16 种个性因素问卷,症状自评量表,紧张性生活事件量表,社会支持评定量表测评。结果 揭示飞行员不成熟防御机制与心理健康水平,生活事件,社会支持显著相关,个性因素明显的影响不成熟防御机制;患病飞行员采用不成熟防御机制明显的多。结论 在飞行员心理卫生保健工作中,揭示并修正飞行员不成熟防御机制是十分必要的。 相似文献
20.
将40只体重20~24g昆明种小鼠随机分为4组,在建立急性低压缺氧导致小鼠学习记忆障碍模型基础上,采用跳台和避暗两种实验方法观察了苯妥英钠(DPH)对小鼠学习记忆障碍的影响.结果表明,急性低压缺氧(8km,停留30min)可导致小鼠学习记忆障碍;灌服DPH(40mg/kg)有一定的防治作用. 相似文献