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151.
OBJECTIVE: To determine the efficacy, immunogenicity and safety of the heptavalent CRM197 pneumococcal conjugate vaccine (PCV) in low birth weight (LBW) and preterm (PT) infants against invasive pneumococcal disease caused by vaccine types. METHODS: In a randomized double blind trial of 37,868 infants given either PCV or meningococcal type C conjugate vaccine (MCV), 1756 infants <750 g <2500 g (LBW) and 4340 infants from 32 to <38 weeks old (PT) were identified. Risk of invasive pneumococcal disease in LBW and PT infants was compared with risk in normal birth weight (NBW) and full term (FT) infants. Local and systemic events observed within 48 h of recent vaccine were assessed by telephone interviews and similar comparisons made. Premature infant Emergency Department visits and hospitalization were also identified and compared with FT and NBW infants. RESULTS: Initiation of immunization and intervals between doses were similar for all groups. The risk ratio for invasive pneumococcal diseases for LBW infants compared with NBW infants was 2.6 (P = 0.03), and for PT compared with FT infants the risk ratio was 1.6 (P = 0.06). Vaccine efficacy for both groups was 100%. PCV was as immunogenic in LBW and PT as in NBW and FT infants. Fever and local events after PCV vaccination were similar when adjusted for clustering among multiple doses per child. When stratified for individual doses there was more redness and swelling for LBW infants and more swelling for PT infants after Dose 3. Isolated local and systemic reactions were more commonly seen with PCV than with MCV, a pattern similar to that in NBW and FT infants. Hospitalization rates were similar for PCV and MCV recipients. CONCLUSION: These data support the use of PCV in LBW infants and PT infants.  相似文献   
152.
Health impacts due to fungi in indoor air can only be estimated reliably, if both fungal propagules and fungal secondary metabolites are qualified and quantified. In the present study, the fungal species composition in a compost facility is compared to the spectrum of microbial metabolites in the air with regard to the physiological properties of different fungal species. A number of relevant fungi was tested for the production of both volatile and non-volatile metabolites on different substrata. The profiles of mycotoxins and microbial volatile organic compounds (MVOC) turned out to be specific for certain species in pure culture. Consequently, the fungi may have different toxicological health impacts, though information on the relevance of microbial volatiles is still limited.  相似文献   
153.

Purpose

Treatment of vascular malformations requires the placement of a needle within vessels which may be as small as 1 mm, with the current state of the art relying exclusively on two-dimensional fluoroscopy images for guidance. We hypothesize that the combination of stereotactic image guidance with existing targeting methods will result in faster and more reproducible needle placements, as well as reduced radiationexposure, when compared to standard methods based on fluoroscopy alone.

Methods

The proposed navigation approach was evaluated in a phantom experiment designed to allow direct comparison with the conventional method. An anatomical phantom of the left forearm was constructed, including an independent control mechanism to indicate the attainment of the target position. Three interventionalists (one inexperienced, two of them frequently practice the conventional fluoroscopic technique) performed 45 targeting attempts utilizing the combined and 45 targeting attempts utilizing the standard approaches.

Results

In all 45 attempts, the users were able to reach the target when utilizing the combined approach. In two cases, targeting was stopped after 15 min without reaching the target when utilizing only the C-arm. The inexperienced user was faster when utilizing the combined approach and applied significantly less radiation than when utilizing the conventional approach. Conversely, both experienced users were faster when using the conventional approach, in one case significantly so, with no significant difference in radiation dose when compared to the combined approach.

Conclusions

This work presents an initial evaluation of a combined navigation fluoroscopy targeting technique in a phantom study. The results suggest that, especially for inexperienced interventionalists, navigation may help to reduce the time and the radiation dose. Future work will focus on the improvement and clinical evaluation of the proposed method.
  相似文献   
154.
BACKGROUND: Loss of elastin is the initiating event in abdominal aortic aneurysm (AAA) formation, whereas loss of collagen is required for continued expansion. The elastolytic matrix metalloproteinases (MMPs) 2 and 9 are well described, but the source of excessive collagenolysis remains undefined. The aim of this study was to determine the expression of MMP-8, a potent type I collagenase, in normal aorta and AAA. METHODS: Infrarenal aortic biopsies were taken from 40 AAA and ten age-matched normal aortas. The concentrations of MMP-8 protein and its inhibitors, tissue inhibitor of metalloproteinase (TIMP) 1 and TIMP-2, were quantified by enzyme-linked immunosorbent assay. Immunohistochemistry was used to localize MMP-8 expression. RESULTS: MMP-8 concentrations were significantly raised in AAA compared with normal aorta (active MMP-8: 4.5 versus 0.5 ng per mg protein, P < 0.001; total MMP-8: 16.6 versus 2.8 ng per mg protein, P < 0.001). Levels of TIMP-1 and TIMP-2 were significantly lower in AAA than in normal aortic samples (TIMP-1: 142.2 versus 302.8 ng per mg protein; P = 0.010; TIMP-2: 9.2 versus 33.1 ng per mg protein, P < 0.001). Immunohistochemistry localized MMP-8 to mesenchymal cells within the adventitia of the aortic wall. CONCLUSION: The high concentration of MMP-8 in aortic aneurysms represents a potent pathway for collagen degradation, and hence aneurysm formation and expansion.  相似文献   
155.
BackgroundLess than 5% of medulloblastoma (MB) patients survive following failure of contemporary radiation-based therapies. Understanding the molecular drivers of medulloblastoma relapse (rMB) will be essential to improve outcomes. Initial genome-wide investigations have suggested significant genetic divergence of the relapsed disease.MethodsWe undertook large-scale integrated characterization of the molecular features of rMB—molecular subgroup, novel subtypes, copy number variation (CNV), and driver gene mutation. 119 rMBs were assessed in comparison with their paired diagnostic samples (n = 107), alongside an independent reference cohort sampled at diagnosis (n = 282). rMB events were investigated for association with outcome post-relapse in clinically annotated patients (n = 54).ResultsSignificant genetic evolution occurred over disease-course; 40% of putative rMB drivers emerged at relapse and differed significantly between molecular subgroups. Non-infant MBSHH displayed significantly more chromosomal CNVs at relapse (TP53 mutation-associated). Relapsed MBGroup4 demonstrated the greatest genetic divergence, enriched for targetable (eg, CDK amplifications) and novel (eg, USH2A mutations) events. Importantly, many hallmark features of MB were stable over time; novel subtypes (>90% of tumors) and established genetic drivers (eg, SHH/WNT/P53 mutations; 60% of rMB events) were maintained from diagnosis. Critically, acquired and maintained rMB events converged on targetable pathways which were significantly enriched at relapse (eg, DNA damage signaling) and specific events (eg, 3p loss) predicted survival post-relapse.ConclusionsrMB is characterised by the emergence of novel events and pathways, in concert with selective maintenance of established genetic drivers. Together, these define the actionable genetic landscape of rMB and provide a basis for improved clinical management and development of stratified therapeutics, across disease-course.  相似文献   
156.

Background  

Compliance represents a major determinant for the effectiveness of pharmacotherapy. Compliance reports summarising electronically compiled compliance data qualify healthcare needs and can be utilised as part of a compliance enhancing intervention. Nevertheless, evidence-based information on a sufficient level of compliance is scarce complicating the interpretation of compliance reports. The purpose of our pilot study was to determine the compliance of ambulatory Alzheimer patients to antidementia drugs under routine therapeutic use using electronic monitoring. In addition, the forgiveness of donepezil (i.e. its ability to sustain adequate pharmacological response despite suboptimal compliance) was characterised and evidence-based guidance for the interpretation of compliance reports was intended to be developed.  相似文献   
157.
Using a subtractive hybridization method, we have cloned 48 cDNAs which are expressed in human primary myoblasts but down-regulated in the embryonal-rhabdomyosarcoma (RMS) cell line RD. Twenty-nine sequences could be identified as coding for previously known gene products, while 19 encode unknown proteins. Twelve clones coding for known proteins that were highly down-regulated in the RD cells were chosen for further analysis on Northern blots containing additional normal and RMS cells. The expression pattern of TGF-β-induced gene product-3 (βigH3), inhibitory G-protein alpha sub-unit (Gαi2), osteoblast-specific factor-2 (OSF-2), 22-kDa smooth-muscle protein (SM22), clone A3351 (homologous to mouse talin), testican, thrombospondin-1 and thrombospondin-2 suggests involvement of these proteins in the genesis of the neoplastic phenotype. Among the clones with unknown sequence, several are identical or homologous to expressed sequence tags or known cDNAs, such as integrins or laminin. These results suggest that several isolated clones might have an important role in the determination or maintenance of the normal phenotype, and thus their loss is possibly involved in the progression of malignancy. © 1996 Wiley-Liss, Inc.  相似文献   
158.
OBJECTIVE: To determine if head-injured patients with premorbid nasal colonization with Staphylococcus aureus are at increased risk for S. aureus infection. DESIGN: Patients admitted over a 2-yr period were enrolled if they met the following criteria: Injury Severity Score > or = 9, intensive care unit (ICU) admission, hospitalization in another hospital < 24 hrs, no recent use of antibiotics. SETTING: Acute care trauma facility. PATIENTS: Any patient sustaining acute, blunt, or penetrating injury and meeting the enrollement criteria were eligible. INTERVENTIONS: Swab cultures of both internal nares were performed within 72 hrs of readmission and cultured for S. Aureus. Patients were prospectively monitored for S. Aureus infections until discharge. MEASUREMENTS AND MAIN RESULTS: Admission nasal cultures were positive (NC+) for S. aureus in 144 of the 776 patients cultured. Forty of the 144 NC+ patients had isolated head (37) or high cervical spine (3) injury, and 11 of that group (27.5%) developed S. aureus infections. The remaining 104 patients positive for S. aureus on admission had no head injury (74) or head combined with torso and extremity injuries (30). S. aureus infection was diagnosed in 11 of the 104 patients (10.6%). The difference in incidence of infections is significant (p <.01), as is the difference in incidence of pneumonia (20% vs. 3.8%, respectively [p <.01]). Organisms causing pneumonia were often the same organisms isolated from the nares on admission. CONCLUSIONS: Nasal colonization with S. aureus at the time of severe head injury increases the risk of S. aureus pneumonia during hospitalization. Prophylactic measures against S. aureus pneumonia may help reduce the length and cost of hospitalization.  相似文献   
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