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101.
Kirsi Nuolivirta Petri Koponen Merja Helminen Matti Korppi 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(1):38-42
Aim: Low birth weight, high birth weight and excessive weight gain after birth may be risk factors for asthma in childhood, but their associations with wheezing in early childhood are poorly studied. The aim of the study was to evaluate birth weight, weight gain in early infancy and overweight in infancy assessed by weight for length (WFL) as risk factors for wheezing after hospitalization for bronchiolitis in early infancy. Methods: In all, 127 full‐term infants hospitalized for bronchiolitis at age <6 months have been followed up until the mean age of 1.5 years. The weights and lengths of the infants were measured on admission to hospital and at the control visit. Birth weights were obtained from the hospital records. Results: Both occurrence and recurrence of post‐bronchiolitis wheezing were associated with birth weight >4000 g and the recurrence of post‐bronchiolitis wheezing with WFL >110% at age 1.5 years. The associations were robust to adjustments with gender and allergy. Higher weight gain from birth to hospitalization at age <6 months was associated with wheezing in the subgroup of children with birth weight >4000 g. Conclusion: High birth weight and the development of overweight may be associated with post‐bronchiolitis wheezing in infancy. 相似文献
102.
High-efficiency gene transfer to primary T lymphocytes by recombinant adenovirus vectors 总被引:3,自引:0,他引:3
Zhi Chen Matti Ahonen Heli Hmlinen Jeffrey M. Bergelson Veli-Matti Khri Riitta Lahesmaa 《Journal of immunological methods》2002,260(1-2):79-89
Recombinant, replication-deficient adenoviruses are efficient vectors for gene transfer to a wide range of cell types, with the exception of T lymphocytes. Here, we show that primary T lymphocytes from peripheral blood, cord blood, and the Jurkat T cell line are efficiently transduced by recombinant adenovirus. Nearly 100% infection efficiency of primary T cells is obtained with high multiplicity of infection (MOI) (5000) of recombinant adenovirus coding for lacZ. Similar infection efficiency by adenovirus-mediated gene transfer was obtained at lower MOI (3000) by activating primary T cells with PHA and PMA. Addition of cationic liposomes together with RAdlacZ markedly enhanced the infection efficiency at lower MOI (1000) resulting in over 90% infection efficiency. Primary T cells express low levels of coxsackievirus and adenovirus receptor (CAR), a cell surface receptor for adenovirus fiber attachment, as well as vβ3 and vβ5 integrins, cellular receptors for adenovirus internalization. This suggests that adenovirus entry to T cells at high MOI is mediated by other mechanisms. In conclusion, these results demonstrate that genes can be efficiently transferred to primary lymphocytes by adenovirus vectors at high MOI or in combination with cationic liposomes. 相似文献
103.
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105.
Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae) 下载免费PDF全文
Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
106.
Hannula A Venhola M Perhomaa M Pokka T Renko M Uhari M 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(12):e253-e259
Aim: To evaluate whether ultrasonography (US) alone is sufficient in imaging the urinary tract in 1185 children with urinary tract infection (UTI). Methods: The reports on US and voiding cystourethrography (VCUG) were reviewed. Results: Initial US was normal in 861/1185 patients (73%). VCUG revealed abnormal findings in 285/861 (33%), of which grade III–V vesicoureteral reflux (VUR) comprised 97 cases (11%). During follow‐up, VUR had resolved in 88/97 (91%) patients: in 50/57 (88%) patients without active treatment for VUR, in 27/29 (93%) with endoscopic and in 11/11 (100%) with open surgery for VUR. During follow‐up, 11/97 patients (11%) had developed new renal scarring detectable in US, but no renal impairment occurred. Except for VUR, VCUG showed nonobstructive urethral valves in two infant boys with normal initial US. Thus, in 861 children with normal initial US, 40 patients with grade III–V VUR and two patients with significant nonreflux pathology may have benefited from surgical treatment, giving the total number of possibly missed pathological finding in 42/861 (4.9%) cases if VCUG had not been performed. Conclusion: We suggest that children with UTI could be examined using US alone and to use VCUG only after additional indications. 相似文献
107.
108.
Alginate-based microencapsulation of retinal pigment epithelial cell line for cell therapy 总被引:2,自引:0,他引:2
Wikström J Elomaa M Syväjärvi H Kuokkanen J Yliperttula M Honkakoski P Urtti A 《Biomaterials》2008,29(7):869-876
The goals of this study were to evaluate human retinal pigment epithelial cell line (ARPE-19) for cell encapsulation and to optimize the alginate-based microencapsulation. We used immortalized ARPE-19 cells and the transfected sub-line that expresses secreted alkaline phosphatase (SEAP) reporter enzyme. Alginate was cross-linked with different divalent cations (Ca(2+), Ba(2+), Sr(2+) and combination of Ca(2+) and Ba(2+)), coated first with poly-l-lysine (PLL), and then with alginate. Microcapsules with different pore sizes and stability were generated. The pore size of the microcapsules was assessed by the release of encapsulated fluorescein isothiocyanate (FITC)-dextrans. The viability of the cells in the microcapsules was studied in vitro by assessing the secretion rates of SEAP and oxygen consumption by the cells. The best microcapsule morphology, durability and cellular viability were obtained with alginate microcapsules that were cross-linked with Ca(2+) and Ba(2+) ions and then coated with PLL and alginate. Based on FITC-dextran release these microcapsules have porous wall that enables the rapid contents release. The ARPE-19 cells maintained viability in the Ca(2+) and Ba(2+) cross-linked microcapsules for at least 110 days. The alginate microcapsules cross-linked with Ca(2+) and Ba(2+) have sufficiently large pore size for prolonged cell viability and for the release of secreted SEAP model protein (Mw 50 kDa; radius of gyration of 3 nm). ARPE-19 cells show long-term viability and protein secretion within alginate microcapsules cross-linked with Ca(2+) and Ba(2+). This combination may be useful in cell therapy. 相似文献
109.
Huang XH Loimaala A Nenonen A Mercuri M Vuori I Pasanen M Oja P Bond G Koivula T Hiltunen TP Nikkari T Lehtimäki T 《Journal of molecular medicine (Berlin, Germany)》1999,77(12):853-858
The insertion/deletion (I/D) polymorphism of the human angiotensin-converting enzyme (ACE) gene is a major determinant of circulating ACE levels. The D allele has been suggested to be a potent risk factor for coronary artery disease; however, the effect of the ACE gene on carotid atherosclerosis remains controversial. We therefore studied the relationship between the ACE gene I/D polymorphism and carotid artery intima-media thickness (IMT). A random sample of 300 men aged 50-59 years living in southern Finland were selected, and 233 agreed to participate (74%). Data were collected in 219 subjects. Quantitative B-mode ultrasonography was used to measure the maximum near and far wall IMT of right and left common, bifurcation, and internal carotid artery. The mean maximum IMT (overall mean) was calculated as the mean of 12 maximum IMTs at 12 standard sites. Patients with an IMT higher than 1.7 mm in at least one of 12 standard sites were assumed to have carotid atherosclerosis. The I/D polymorphism was determined by polymerase chain reaction. Overestimation of the frequency of the DD genotype was eliminated by insertion-specific primer and the inclusion of 5% dimethylsulfoxide. No significant differences were found in carotid wall thickness between the three genotypes; the overall mean IMT were 1.18 +/- 0.30, 1.22 +/- 0.24, and 1.08 +/- 0.40 mm in genotypes of II, ID, and DD, respectively. Similarly, the ACE genotypes and allele frequencies did not differ significantly between the subjects with and those without carotid atherosclerosis. There was no association in the subgroups among only nonsmoking subjects or subjects without chronic medication. The present data indicate that the I/D polymorphism of the ACE gene is not related to carotid IMT and is unlikely to play a major role in carotid atherosclerosis. 相似文献
110.
Population-based study of salivary carriage of periodontal pathogens in adults 总被引:1,自引:1,他引:1 下载免费PDF全文
Könönen E Paju S Pussinen PJ Hyvönen M Di Tella P Suominen-Taipale L Knuuttila M 《Journal of clinical microbiology》2007,45(8):2446-2451
Large, general population-based data on carriage rates of periodontal pathogens hardly exist in the current literature. The objectives of the present study were to examine the salivary detection of Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, Campylobacter rectus, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola in a representative sample of the adult population living in southern Finland and to clarify which determinants are associated with the presence of these pathogens in saliva. 16S rRNA-based PCR methods with species-specific primers were employed to determine the presence of the six target bacteria in stimulated saliva samples, which were available from 1,294 subjects aged > or =30 years. The age group, gender, level of education, marital status, smoking history, number of teeth, and number of teeth with deepened pockets were included in the statistical analysis. In general, the carriage of periodontal pathogens was common, since at least one of the examined pathogens was found in 88.2% of the subjects. In descending order, the total detection rates were 56.9%, 38.2%, 35.4%, 31.3%, 20.0%, and 13.9% for T. forsythensis, T. denticola, P. gingivalis, C. rectus, A. actinomycetemcomitans, and P. intermedia, respectively. Age per se was strongly associated with the carriage of P. gingivalis (P = 0.000), and the level of education with that of T. denticola (P = 0.000). There was an association between the number of teeth with deepened pockets and carriage of P. gingivalis (P = 0.000), P. intermedia (P = 0.000), T. denticola (P = 0.000), and A. actinomycetemcomitans (P = 0.004). The data suggest that distinct species have a different carriage profile, depending on variables such as age, educational level, and periodontal status. 相似文献