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91.
Kuate S  Cinatl J  Doerr HW  Uberla K 《Virology》2007,362(1):26-37
Infection with the SARS-associated coronavirus (SARS-CoV) induces an atypical pulmonary disease with a high lethality rate. Although the initial SARS epidemic was contained, sporadic outbreaks of the disease still occur, suggesting a continuous need for a vaccine against this virus. We therefore explored exosome-based vaccines containing the spike S proteins of SARS-CoV. S-containing exosomes were obtained by replacing the transmembrane and cytoplasmic domains of the S protein by those of VSV-G. The immunogenicity and efficacy of the S-containing exosomes were tested in mice and compared to an adenoviral vector vaccine expressing the S protein. Both, S-containing exosomes and the adenoviral vector vaccine induced neutralizing antibody titers. After priming with the SARS-S exosomal vaccine and boosting with the adenoviral vector the neutralizing antibody titers exceeded those observed in the convalescent serum of a SARS patient. Both approaches were effective in a SARS-S-expressing tumor challenge model and thus warrant further investigation.  相似文献   
92.
Although classical influenza is a clinically typical illness ("unchanging disease due to a changing agent"), laboratory investigations are essential at the beginning of each influenza epidemic. They should confirm suspected influenza cases and exclude "flu-like illnesses" which may be caused by numerous other viral and bacterial agents. Different virological as well as serological methods are available. For early diagnosis of acute influenza virus infections, virus detection using rapid procedures for virus isolation or antigen staining and molecular biological techniques have been developed. The determination of specific antibodies (IgG, IgM) has traditionally been widely used diagnostically. Conventional serological diagnosis is possible by means of the complement fixation and hemagglutination inhibition tests and allows the detection of type- and subtype-specific antibodies, respectively. As part of an automated serology, immunofluorescence test and enzyme-linked immunosorbent assay are the mostly widely available methods. In comparison, virus detection is clearly superior to antibody determination for diagnosis of influenza virus infections. However, antibody testing may be useful as a complementary tool to confirm the diagnosis retrospectively.  相似文献   
93.

Background

Heterozygous gain‐of‐function mutations in various genes encoding proteins of the Ras‐MAPK signalling cascade have been identified as the genetic basis of Noonan syndrome (NS) and cardio‐facio‐cutaneous syndrome (CFCS). Mutations of SOS1, the gene encoding a guanine nucleotide exchange factor for Ras, have been the most recent discoveries in patients with NS, but this gene has not been studied in patients with CFCS.

Methods and results

We investigated SOS1 in a large cohort of patients with disorders of the NS–CFCS spectrum, who had previously tested negative for mutations in PTPN11, KRAS, BRAF, MEK1 and MEK2. Missense mutations of SOS1 were discovered in 28% of patients with NS. In contrast, none of the patients classified as having CFCS was found to carry a pathogenic sequence change in this gene.

Conclusion

We have confirmed SOS1 as the second major gene for NS. Patients carrying mutations in this gene have a distinctive phenotype with frequent ectodermal anomalies such as keratosis pilaris and curly hair. However, the clinical picture associated with SOS1 mutations is different from that of CFCS. These findings corroborate that, despite being caused by gain‐of‐function mutations in molecules belonging to the same pathway, NS and CFCS scarcely overlap genotypically.  相似文献   
94.
In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.   相似文献   
95.
Zusammenfassung Bei einer 37 j?hrigen, bisher gesunden Patientin entwickelte sich eine über 2 Monate progrediente Dyspnoe. Radiologisch und echokardiographisch zeigte sich eine massive Dilatation s?mtlicher Herzh?hlen mit biventrikul?ren Thromben und eine stark herabgesetzte Kontraktilit?t. Die Endomyokardbiopsien wurden von 2 Instituten als Myokarditis eingestuft. Im weiteren Verlauf entwickelten sich thrombembolische Komplikationen und ein therapierefrakt?res Pumpversagen, in dem die Patientin schlie?lich verstarb. Bei der Obduktion fand sich au?er einem dilatierten 600 g schweren Herzen mit biventrikul?ren Thromben ein klinisch bisher unbekanntes Ph?ochromozytom der linken Nebenniere. Die eingehende histologische und immunhistologische Aufarbeitung des Herzmuskelgewebes einschlie?lich Reevaluierung der Endomyokardbiopsien führte zur Revision der ursprünglichen Diagnose: Das Krankheitsbild der 37 j?hrigen Patientin war durch eine katecholamininduzierte dilatative Kardiomyopathie verursacht worden.   相似文献   
96.
Leaves of the tropical tree Moringa oleifera are widely promoted in areas of chronic malnutrition as nutritional supplements for weaning infants and nursing mothers. Adoption, in these circumstances may hinge upon taste, which can vary greatly amongst cultivars. It is widely assumed that this taste variation is primarily germplasm-dependent, and results from the breakdown of glucosinolates to isothiocyanates. Leaves of 30 accessions, grown at a single field plot, were sampled 3 times over the course of a year. Taste, assessed in a masked protocol, was not related to glucosinolate content of the leaves.  相似文献   
97.
During recent years increasing attention has been given to the quality of survival in critical care. Health-related quality of life (HRQOL) is an important issue both for patients and their families. Furthermore, admission to the intensive care unit can have adverse psychological effects in critically ill patients. Recent studies conducted in critically ill patients have measured HRQOL. However, usually absent from such reports are evaluations of conceptual issues, addressing factors such as why HRQOL should be measured in critically ill patients, how to define and standardize domains of HRQOL, whether proxies can provide useful information about HRQOL in critically ill patients, whether response shift occurs in critically ill patients, and whether post-traumatic stress disorder (PTSD) occurs in critically ill patients. Some studies reported moderate agreement between patients and their proxies, although lower levels of agreement may be reported for psychosocial or physical functioning. Response shift (adaptation and change in perception) appears to be an important phenomenon and likely to be present, but it is seldom measured when estimating HRQOL in critically ill patients. Furthermore, vigilance for symptoms of PTSD and early interventions to prevent PTSD are needed.  相似文献   
98.
99.
PURPOSE: Neuroblastomas frequently show expression of the epidermal growth factor receptor (EGFR) and may therefore be susceptible to EGFR-targeted therapies. Here, EGFR expression and functionality was investigated in parental chemosensitive neuroblastoma cell lines (UKF-NB-3, IMR-32, NLF, SH-SY5Y) and their cisplatin-resistant sublines (UKF-NB-3(r)CDDP(1000), IMR-32(r)CDDP(1000), NLF(r)CDDP(1000), and SH-SY5Y(r)CDDP(500)). Moreover, the EGFR antibody cetuximab, the EGFR tyrosine kinase inhibitor Tyrphostin B46, and recombinant EGFR-targeted toxins were investigated for their influence on the viability and growth of neuroblastoma cells. EXPERIMENTAL DESIGN: EGFR expression and function was measured by flow cytometry or Western blot. Cell viability was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptosis was examined by immunostaining for active caspase-3 or cleaved poly(ADP-ribose) polymerase. Cellular binding of FITC-labeled immunotoxins was studied by flow cytometry, and cellular uptake was studied by confocal laser scanning microscopy. RESULTS: The EGFR-targeted antibody and growth factor toxins scFv(14E1)- Pseudomonas exotoxin A (ETA) and TGF-alpha-ETA exerted anti-cancer effects in neuroblastoma cell lines that were insensitive to cetuximab or EGFR tyrosine kinase inhibitors. Furthermore, adaptation of chemosensitive neuroblastoma cells to cisplatin increased EGFR expression and sensitivity to both recombinant toxins. Treatment of chemosensitive neuroblastoma cells with cisplatin reversibly increased EGFR expression, whereas cisplatin-resistant cells showed enhanced EGFR expression independent of the presence of cisplatin. Combination treatment with scFv(14E1)-ETA or TGF-alpha-ETA and cisplatin exerted significantly improved anticancer effects compared with either single treatment in parental neuroblastoma cells, cisplatin-resistant sublines, and primary cultures. CONCLUSIONS: EGFR-targeted cytotoxic reagents such as scFv(14E1)-ETA and TGF-alpha-ETA represent promising candidates for further development as antineuroblastoma agents, especially in combination with cisplatin.  相似文献   
100.
We report the case of a patient with a single liver metastasis of a mucinous colonic carcinoma that mimics a haemangioma in T2‐weighted sequences. Although a very high T2 signal in non‐cystic lesions is highly specific for the diagnostic of haemangioma, the use of gadolinium‐enhancement MRI is recommended. In patients with a history of neoplasia, the diagnosis of benign liver nodules should be made with caution.  相似文献   
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