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61.
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
62.
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
63.
E D'Alessandro V Santiemma M L Lo Re C Ligas G Del Porto 《American journal of medical genetics》1992,44(2):220-222
A woman with a history of recurrent abortions, idiopathic hypoprolactinemia, and an apparent 6p partial deletion mosaicism is described. The breakpoint in the short arm of chromosome 6 was in the p23 region. This deletion could have been caused by a fragile site in 6p23. 相似文献
64.
Lack of CD 29 (beta1 integrin) and CD 54 (ICAM-1) adhesion molecules in intravascular lymphomatosis 总被引:9,自引:0,他引:9
Ponzoni M Arrigoni G Gould VE Del Curto B Maggioni M Scapinello A Paolino S Cassisa A Patriarca C 《Human pathology》2000,31(2):220-226
Intravascular Lymphomatosis (IL) is a rare and usually aggressive form of non-Hodgkin's lymphoma characterized by the growth of neoplastic cells within vascular lumina that usually presents with skin or central nervous system (CNS) involvement. The mechanism(s) for the selective intravascular growth of this neoplasm remain(s) unexplained. We now report clinical and immunohistologic data on surgical material from 6 cases of IL; in 4 of 6 cases, autopsies were performed. Our IL cases shared the following features: (1) B-cell lineage; (2) lack of skin involvement at presentation; (3) aggressive behavior; and (4) lack of extravascular lymphomatous masses; in addition, 1 case had an associated gastric low-grade MALT lymphoma. We studied by immunohistochemistry formalin-fixed, paraffin-embedded sections with monoclonal antibodies to molecules known to be involved in lymphocyte and endothelial adhesion phenomena, that is, CD29 (beta1 integrin subunit), CD43 (leukosialin), CD44 (H-CAM), CD54 (ICAM-1), embryonal N-CAM (e-NCAM), and EMA (episialin). In all cases, the surfaces of IL aggregates reacted for CD44 but were consistently negative for CD29; also absent was CD54. Conversely, the integrity of the endothelial cells was underscored by their even reactivity for CD29, CD44, and CD54. Given that CD29 is currently regarded as critical for lymphocyte trafficking in general and for transvascular migration in particular, and CD54 is also involved in transvascular lymphocyte migration, we conclude that their consistent absence in IL may contribute to its intravascular and disseminated distribution pattern. The rather frequent association of IL with various conventional lymphomas is known; yet, one of our cases appears to be the first report of IL associated with a low-grade MALT lymphoma. 相似文献
65.
66.
Angiomyolipoma is a lesion usually observed in the kidney of patients with tuberous sclerosis. Extrarenal sites are very unusual with sporadic cases in internal organ, soft tissue and skin (fifteen cases have been described in this site). Herein we describe an adding case located on the ear in 58-year-old man reviewing the pertinent literature. The main diagnostic differential criteria are also discussed. 相似文献
67.
A. Canessa V. Del Bono P. De Leo N. Piersantelli A. Terragna 《European journal of clinical microbiology & infectious diseases》1992,11(2):125-130
Twenty-four consecutive HIV-positive patients affected byToxoplasma gondii encephalitis received trimethoprim-sulfamethoxazole (cotrimoxazole) as acute-phase treatment. Two dosage regimens of cotrimoxazole were used: 40 mg/kg/day (12 patients) or 120 mg/kg/day (12 patients) of total compound (trimethoprim plus sulfamethoxazole). Clinical and radiological responses to treatment were evaluated, and the product-limit method for survival data analysis was used. Eighteen of 24 patients showed both a clinical and radiological response (75 % response rate). There were no differences in response rates between patients receiving the two dosage regimens of cotrimoxazole. Adverse reaction consisted of leukopenia (two cases) and skin rash (three cases) which led to the discontinuation of the drug in one case. These results suggest that a randomized, controlled clinical trial should be carried out comparing cotrimoxazole versus sulfadiazine-pyrimethamine in AIDS patients withToxoplasma gondii encephalitis.Deceased. 相似文献
68.
Multiple pathways of cell invasion are regulated by multiple families of serine proteases 总被引:5,自引:0,他引:5
Del Rosso M Fibbi G Pucci M D'Alessio S Del Rosso A Magnelli L Chiarugi V 《Clinical & experimental metastasis》2002,19(3):193-207
The complex process of tumor invasion requires the coordinated expression and activity of cell-substratum adhesive interactions
and of cell-associated protease systems, which destroy the extracellular matrix (ECM), in order to enable the invading cells
to simultaneously grip and destroy the anatomical barriers that control cell spreading. A number of data indicate that such
a `grip and go' process may be performed by an enlarging series of cell membrane-associated serine proteases and serine protease
receptors, which provide the invasive cells with a functional unit (the protease and its receptor), able to mediate cell-substratum
adhesion through specific receptor domains, to proteolytically degrade ECM and to deliver into the cell signals that up-regulate
the expression either of the protease/receptor complex, or of other adhesion molecules, such as integrins. There is evidence
that some proteases and protease receptor expression are under the control of tumor hypoxia, which is the result of an imbalance
in oxygen supply and demand. The urokinase-type plasminogen activator (u-PA) receptor (u-PAR) is under hypoxic control and
cooperates with other serine proteases of the blood coagulation pathways that may extravasate in the tumor milieu as a result
of hypoxia-simulated increase of vessel permeability. Other serine proteases and their receptors cooperate with the cell-associated
fibrinolytic system to promote cell invasion. Among these, tissue factor and its ligand coagulation factor VII, thrombin and
its protease-activated receptors, and type II trans-membrane serine proteases seem to play a crucial role. This Review takes
into consideration the complex scenario of the single serine proteases and related receptors that are involved in cell invasion,
as well as the protease receptor/adhesion molecule interplay which is necessary to focus the cell surface-driven proteolysis
where adhesion provides a grip to the invading cell.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
69.
Macrolide efflux genes mef(A) and mef(E) are carried by different genetic elements in Streptococcus pneumoniae 总被引:8,自引:0,他引:8 下载免费PDF全文
Del Grosso M Iannelli F Messina C Santagati M Petrosillo N Stefani S Pozzi G Pantosti A 《Journal of clinical microbiology》2002,40(3):774-778
Susceptibilities to macrolides were evaluated in 267 Streptococcus pneumoniae isolates, of which 182 were from patients with invasive diseases and 85 were from healthy carriers. Of the 98 resistant isolates, 20 strains showed an M phenotype and carried mef. Strains that carried both mef(A) and mef(E) were found: 17 strains carried mef(A) and 3 carried mef(E). The characteristics of the strains carrying the mef genes and the properties of the mef-containing elements were studied. Strains carrying mef(A) belonged to serotype 14, were susceptible to all the antibiotics tested except erythromycin, and appeared to be clonally related by pulsed-field gel electrophoresis (PFGE). The three mef(E) strains belonged to different serotypes, showed different susceptibility profiles, and did not appear to be related by PFGE. The sequences of a fragment of the mef-containing element, which encompassed mef and the msr(A) homolog, were identical among the three mef(E)-positive strains and among the three mef(A)-positive strains, although there were differences between the sequences for the two variants at 168 positions. In all mef(A)-positive strains, the mef element was inserted in celB, which led to impairment of the competence of the strains. In line with insertion of the mef(E) element at a different site, the competence of the mef(E)-positive strains was maintained. Transfer of erythromycin resistance by conjugation was obtained from two of three mef(A) strains but from none of three mef(E) strains. Due to the important different characteristics of the strains carrying mef(A) or mef(E), we suggest that the distinction between the two genes be maintained. 相似文献
70.
Taylor GP Bodéus M Courtois F Pauli G Del Mistro A Machuca A Padua E Andersson S Goubau P Chieco-Bianchi L Soriano V Coste J Ades AE Weber JN 《Journal of acquired immune deficiency syndromes (1999)》2005,38(1):104-109
BACKGROUND: Up to 20 million persons are infected with the human retroviruses human T-lymphotropic virus (HTLV)-I and HTLV-II globally. Most data on the seroprevalence of HTLV-I and HTLV-II in Europe are from studies of low-risk blood donors or high-risk injection drug users (IDUs). Little is known about the general population. METHODS: A prospective anonymous study of HTLV-I and HTLV-II seroprevalence among 234,078 pregnant women in Belgium, France, Germany, Italy, Portugal, Spain, and the United Kingdom was conducted. Maternal antibody status was determined by standard methods using sera obtained for routine antenatal infection screens or eluted from infant heel prick dried blood spots obtained for routine neonatal metabolic screens. RESULTS: Anti-HTLV-I/II antibodies were detected and confirmed in 96 pregnant women (4.4 per 10,000, 95% confidence interval [CI]: 3.5-5.2). Of these, 73 were anti-HTLV-I, 17 were anti-HTLV-II, and 6 were specifically anti-HTLV but untyped. The seroprevalence ranged from 0.7 per 10,000 in Germany to 11.5 per 10,000 in France. CONCLUSIONS: Pregnant women better reflect the general population than blood donors or IDUs. The seroprevalence of HTLV-I and HTLV-II in Western Europe is 6-fold higher among pregnant women (4.4 per 10,000) than among blood donors (0.07 per 10,000). These data provide a robust baseline against which changes in HTLV-I and HTLV-II seroprevalence in Europe can be measured. 相似文献