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21.
We conducted a longitudinal evaluation of a patient with systemic lupus erythematosus who constitutively exhibited elevated levels of circulating α-interferon (α-IFN). This study demonstrated that the serum levels of an activity that renders the endogenous α-IFN acid labile are positively correlated with disease activity. This IFN acid lability-inducing activity can also be found in the sera of systemic lupus erythematosus patients who have active disease but who do not have circulating α-IFN.  相似文献   
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Bogdanova NV, Antonenkova NN, Rogov YI, Karstens JH, Hillemanns P, Dörk T. High frequency and allele‐specific differences of BRCA1 founder mutations in breast cancer and ovarian cancer patients from Belarus. Breast cancer and ovarian cancer are common malignancies in Belarus accounting for about 3500 and 800 new cases per year, respectively. For breast cancer, the rates and age of onset appear to vary significantly in regions differentially affected by the Chernobyl accident. We assessed the frequency and distribution of three BRCA1 founder mutations 5382insC, 4153delA and Cys61Gly in two hospital‐based series of 1945 unselected breast cancer patients and of 201 unselected ovarian cancer patients from Belarus as well as in 1019 healthy control females from the same population. Any of these mutations were identified in 4.4% of the breast cancer patients, 26.4% of the ovarian cancer patients and 0.5% of the controls. In the breast cancer patients, BRCA1 mutations were strongly associated with earlier age at diagnosis, with oestrogen receptor (ER) negative tumours and with a first‐degree family history of breast cancer, although only 35% of the identified BRCA1 mutation carriers had such a family history. There were no marked differences in the regional distribution of BRCA1 mutations, so that the significant differences in age at diagnosis and family history of breast cancer patients from areas afflicted by the Chernobyl accident could not be explained by BRCA1. We next observed a higher impact and a shifted mutational spectrum of BRCA1 in the series of Byelorussian ovarian cancer patients where the three founder mutations accounted for 26.4% (53/201). While the Cys61Gly mutation appeared underrepresented in ovarian cancer as compared with breast cancer cases from the same population (p = 0.01), the 4153delA mutation made a higher contribution to ovarian cancer than to breast cancer (p < 0.01). BRCA1 mutations were significantly enriched among ovarian cancer cases with a first‐degree family history of breast or ovarian cancer, whereas the median age at ovarian cancer diagnosis was not different between mutation carriers and non‐carriers. Taken together, these results identify three BRCA1 founder mutations as key components of inherited breast and ovarian cancer susceptibility in Belarus and might have implications for cancer prevention, treatment and genetic counselling in this population.  相似文献   
25.
We studied the pathogenesis and transmissibility of a novel avian-origin H7N9 influenza virus in pigs. When pigs were infected with H7N9 influenza virus, they did not show any clear clinical signs (such as sneezing, fever and loss of body weight), and they shed viruses through their noses for 2 days after infection. No transmission occurred between infected and naïve pigs. Pigs suffered from mild pneumonia, which was accompanied by the induction of inflammatory cytokines and chemokines such as IL-8 and CCL1. Taken together, our results suggest that pigs may not play an active role in transmitting H7N9 influenza virus to mammals.  相似文献   
26.

Background

The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression.

Objectives

To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and micro-vascular endothelial cells (dMVECs).

Methods

Increasing concentrations of selective B1R and B2R agonists were added to cultured cells. Cell proliferation and migration were assessed using the 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and modified Boyden Chamber assays, respectively. Where significant stimulation was found, the influence of an antagonist was also investigated.

Results

Neither growth nor motility of endothelial cells was affected by either agonist. In DU145 cells, while the B2R agonist was without any significant effect, the B1R agonist stimulated proliferation and migration at concentrations of 10nM and 50nM respectively. Further, this effect was abrogated when cells were pre-incubated with a B1R antagonist.

Conclusions

Unlike the physiologically-active B2R, the pathologically-inducible B1R may be implicated in prostate tumourigenic events. The involvement of the KKS in malignant prostate pathology supports on-going exploration of bradykinin receptor antagonists as target candidates in the development of alternate approaches to cancer therapy.  相似文献   
27.
Sarcomas are a diverse group of malignant mesenchymal tumours arising from bone and soft tissues. The identification of critical cellular signalling pathways in sarcomas is an important issue for the development of new targeted therapies. This review highlights the experimental and clinical evidence supporting the role of the insulin‐like growth factor (IGF) signalling system in the cellular transformation and progression of several types of sarcoma, including rhabdomyosarcoma, synovial sarcoma, leiomyosarcoma, Ewing's sarcoma and osteosarcoma. Preclinical data suggest that the IGF system could be a promising target for therapy in these sarcomas. Currently, therapies interrupting IGF signalling have been or are being developed. In recent phase 1 clinical studies with humanized monoclonal antibodies directed against IGF receptor type 1 (IGF‐1R), objective tumour responses were observed in several patients with Ewing's sarcoma, encouraging further clinical testing in Ewing's sarcoma and other sarcoma (sub)types. Moreover, the occasional occurrence of paraneoplastic hypoglycaemia as a result of the secretion of incompletely processed forms of pro‐IGF‐II by sarcomas is discussed. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
28.
BackgroundAtopic dermatitis (AD) is a heterogeneous disease with different age of onset, disease course, clinical symptoms, severity, and risk of comorbidity. The characteristics of children with AD also vary by age or country. However, little is known about the clinical characteristics of AD in Korean school-aged children and adolescents. Furthermore, there are few studies on phenotypic differences according to onset age. This study aimed to explore the clinical characteristics and phenotypes according to onset age and severity of AD in children and adolescents in Korea.MethodsAD patients aged 6–18 years who presented to 18 hospitals nationwide were surveyed. The patients were examined for disease severity by pediatric allergy specialists, and data on history of other allergic diseases, familial allergy history, onset age, trigger factors, lesion sites, treatment history and quality of life were collected. The results of the patient’s allergy test were also analyzed. The patients were classified into infancy-onset (< 2 years of age), preschool-onset (2–5 years of age), and childhood-onset (≥ 6 years of age) groups. Study population was analyzed for clinical features according to onset-age groups and severity groups.ResultsA total of 258 patients with a mean age of 10.62 ± 3.18 years were included in the study. Infancy-onset group accounted for about 60% of all patients and presented significantly more other allergic diseases, such as allergic rhinitis and asthma (P = 0.002 and P = 0.001, respectively). Food allergy symptoms and diagnoses were highly relevant to both earlier onset and more severe group. Inhalant allergen sensitization was significantly associated with both infancy-onset group and severe group (P = 0.012 and P = 0.024, respectively). A family history of food allergies was significantly associated with infancy-onset group (P = 0.036). Severe group was significantly associated with a family history of AD, especially a paternal history of AD (P = 0.048 and P = 0.004, respectively). Facial (periorbital, ear, and cheek) lesions, periauricular fissures, hand/foot eczema, and xerosis were associated with infancy-onset group. The earlier the onset of AD, the poorer the quality of life (P = 0.038). Systemic immunosuppressants were used in only 9.6% of the patients in the severe group.ConclusionThis study analyzed the clinical features of AD in Korean children and adolescents through a multicenter nationwide study and demonstrated the phenotypic differences according to onset age and severity. Considering the findings that the early-onset group is more severe and accompanied by more systemic allergic diseases, early management should be emphasized in young children and infants.  相似文献   
29.
Lefevre JH, Colas C, Coulet F, Baert‐Desurmont S, Mongin C, Tiret E, Frebourg T, Soubrier F, Parc Y. Frequent mutation in North African patients with MUTYH‐associated polyposis. MUTYH‐associated polyposis (MAP) has been characterized as an autosomal recessive disease predisposing to a variable number of colorectal adenomas with a high risk of cancer. Numerous studies have indicated that two missense mutations (Y179C and G396D) account for about 80% of MUTYH allelic variants in Europeans. Ethnic and geographic differences in the mutation spectrum have been observed. The aim of this study was to report mutations in patients from North Africa, determine the incidence of the c.1227_1228dup mutation in our cohort of MUTYH patients and to evaluate the existence of a founder effect. Within a group of 36 families with MAP, 11 were shown to have a homozygous c.1227_1228dup mutation. These families came from Algeria (n = 5), Tunisia (n = 4), Morocco (n = 1) and Portugal (n = 1). Probands belonging to families of North African origin showed a significantly higher frequency of c.1227_1228dup (78.6% vs 4.5%, p < 0.0001). Haplotype analyses were performed using 10 microsatellite markers surrounding the MUTYH gene spanning a region of 4.4 cM. We identified a common haplotype of at least 1.3 cM in all families suggesting a founder effect for this mutation.  相似文献   
30.
A semicrystalline low‐bandgap polymer (PDTPBT) based on alternating dithienopyrrole and benzothiadiazole moieties as a pair of the indene‐C60 bisadduct (ICBA) for polymeric solar cells is reported. The lowest unoccupied molecular orbital (LUMO) level of PDTPBT is measured to be ?3.47 eV, ensuring sufficient energy offset for photoinduced charge transfer to ICBA. Photovoltaic cells are fabricated with ICBA and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) as an acceptor. By replacing PC71BM with ICBA, the open‐circuit voltage is increased by 0.23 V and the resulting power conversion efficiency is improved from 1.17% to 1.71%. To optimize the ICBA‐based devices, crystalline low‐bandgap structures should be designed carefully as a pair of ICBA by considering the energy‐level offset for charge separation and crystalline interchain ordering, for minimizing the intercalated ICBAs inside the polymer domain.

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