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51.
Current seasonal influenza vaccines have reduced immunogenicity and are of suboptimal efficacy in older adults. We have previously shown that the novel candidate vaccine MVA-NP+M1 is able to boost memory T cell responses in adults aged 50–85 years. Preclinical studies have demonstrated that viral vectored vaccines can act as adjuvants when coadministered with protein-based vaccines. We have conducted a phase I clinical trial to compare the coadministration of seasonal influenza vaccine and MVA-NP+M1 with seasonal influenza vaccine alone in adults aged 50 years and above. This combination of vaccines was safe and well tolerated. T cell responses to internal influenza proteins were boosted to significantly higher levels in the group receiving MVA-NP+M1 compared with the group receiving seasonal influenza vaccine alone. Rates of seroprotection and seroconversion against the three vaccine strains were similar in both groups; however, there was a significant increase in the geometric mean titer ratio for the H3N2 component of seasonal influenza vaccine in the coadministration group. While some vaccine combinations result in immune interference, the coadministration of MVA-NP+M1 alongside seasonal influenza vaccine is shown here to increase some influenza strain-specific antibody responses and boost memory T cells capable of recognizing a range of influenza A subtypes.  相似文献   
52.
53.
BACKGROUND: Previous studies of transfusions of newly formed red cells (neocytes) demonstrated modest extensions of transfusion interval in patients with homozygous beta-thalassemia. STUDY DESIGN AND METHODS: The clinical benefits of a new system of neocyte preparation (Neocel, Cutter Biological, Berkeley, CA), reported to combine ease of preparation with reduction in the transfusion requirements of thalassemia patients, were evaluated. Sixteen thalassemic patients who had undergone splenectomy received eight consecutive, standard, automated, washed red cell transfusions (standard transfusions), followed by eight transfusions with the neocyte preparation (neocyte transfusions). In each arm of the study, mean pretransfusion hemoglobin and mean red cell mass transfused were carefully controlled and were similar. RESULTS: A significant (p < 0.0001) extension of transfusion interval was observed in patients receiving neocyte transfusions (mean +/− SD; 38.7 +/− 34 days; range, 35.0-44.5), over that in those receiving standard transfusions (32.9 +/− 2.5 days; range, 29.6-38.5). The mean prolongation of transfusion interval by neocyte transfusion corresponded to a mean reduction of 25 mL in packed red cells transfused per kg of body weight per patient per year and a mean reduction in transfused iron of 15 percent per year per patient. During neocyte transfusions, blood preparation costs were considerably increased and donor exposure was significantly (p < 0.0005) higher than during the standard transfusion period. CONCLUSION: These data demonstrate that extension of the transfusion interval, and reduction in transfused iron, may be achieved in thalassemic patients by use of the Neocel system. These benefits are achieved, however, with substantial increases in donor exposure and in component preparation costs.  相似文献   
54.
ObjectiveTo investigate the presence of statistically significant geographical clusters of tuberculosis (TB) using Geographical Information System and spatial scan statistics in Dehradun, India.MethodsThe spatial scan statistic implemented with a software program, SaTScan v6.1, was used to test the presence of statistically significant spatial clusters of TB and to identify their approximate locations (P< 0.05 for primary clusters and P<0.1 for secondary clusters). Geographical Information System was used for geographical analysis.ResultsSignificant high rate spatial clusters were identified in seven wards of the Dehradun Municipal area.ConclusionsThere is sufficient evidence about the existence of statistically significant TB clusters in seven wards of Dehradun, India. The purely spatial scan statistics methodology used in this study has a potential use in surveillance of TB for detecting the true clusters of the disease.  相似文献   
55.

Background

Hypofractionation has become standard of care after Breast Conserving Therapy (BCT) in many European and few others western countries. Though still debatable, tumor cavity boost is routinely practised in our centre. Hypofractionation is not yet the current standard of practice in Asian countries. Employing hypofractionation and simultaneous integrated boost to lumpectomy cavity with conformal technique is not the current practice in this region. Hence the study was performed to see whether accelerated hypofractionation and simultaneous boost can be combined using volumetric modulated arc therapy (VMAT) in treating early breast cancer (EBC) patients.

Patients and methods

Female patients with EBC treated by whole breast radiation and boost were treated simultaneously to a dose of 40.5 Gy and 48 Gy in fifteen fractions over three weeks to entire breast and tumor cavity respectively with VMAT. Dosimetry including target coverage, OAR (organ at risk) sparing and acute radiation toxicity were evaluated.

Results

Ten consecutive patients were treated. Planning target volume (PTV) coverage and OAR sparing were mostly satisfactory. Mean volume of PTVWB and PTVBoost were 786.18 cm3 and 228.9 cm3 respectively. Mean Dmean to PTVWB and PTVBOOST were 41.9 Gy and 49.1 Gy respectively. Dmax to PTVWB and PTVBOOST were 127.56% and 110.67% respectively. Ipsilateral lung mean dose and V20 were 13.92 Gy and 21.53% respectively. V40 and V25 of heart were 0.17% and 2.25% respectively. All patients are disease free after a median follow up of two years. Most acute toxicities were Grade1. Only two patients out of ten developed Grade 2 skin reaction during radiation. Early cosmesis using Harvard cosmesis scale is good to excellent.

Conclusions

Accelerated hypofractionated RT using SIB-VMAT is a clinically feasible technique with acceptable initial result. Initial results are encouraging.

Mini abstract

Simultaneous integrated boost with accelerated hypofractionated whole breast radiotherapy using Volumetric Modulated Arc Therapy is a novel approach. Patient selection and technical considerations are of paramount importance. The present study describes successful implementation of this approach.  相似文献   
56.
Breast cancer is the second leading cause of death in women. It occurs when cells in the breast start to grow out of proportion and invade neighboring tissues or spread throughout the body. Mammography is one of the most effective and popular modalities presently used for breast cancer screening and detection. Efforts have been made to improve the accuracy of breast cancer diagnosis using different imaging modalities. Ultrasound and magnetic resonance imaging have been used to detect breast cancers in high risk patients. Recently, electrical impedance imaging and nuclear medicine techniques are also being widely used for breast cancer screening and diagnosis. In this paper, we discuss the capabilities of various breast imaging modalities.  相似文献   
57.
The effects of Cr(III) and Cr(VI) on the survival, behavior, and morphology of the earthworm, Eisenia fetida, in water at pH 6, 7, and 8 and their toxicity in 10 different soils and an organic substrate have been assessed. A decrease in the pH of water resulted in increased toxicity of Cr to the earthworm. In water, both Cr species produced behavioral changes and morphological symptoms. The 48-h LC(50) values of Cr(III) at pH 6, 7, and 8 were 1.93, 2.55, and 2.78 mg/L, and those of Cr(VI) were 0.47, 0.61, and 0.63 mg/L, respectively. The 14-day median lethal concentrations (LC(50)) of Cr(III) and Cr(VI) for earthworm range from 1656 to 1902 mg/kg for Cr(III) and from 222 to 257 mg/kg for Cr(VI) in soil. In the organic substrate, the LC(50) values of Cr(III) and Cr(VI) were 1635 and 219 mg/kg, respectively. Stepwise multiple regression analysis predicted that clay content of soils accounted for 92% and 88% of the variation in the LC(50) values of Cr(III) and Cr(VI), respectively.  相似文献   
58.
Background: Proliferative vitreo-retinopathy (PVR) is the most common cause of failed repair of a primary rhegmatogenous retinal detachment (RRD). The success rates for the surgery of complicated RRD has doubled with improved vitreous techniques from 35-40% to approximately 65-75% at six months. However, despite these advances, recurrent vitreo-retinal traction leads to re-detachment in more than one-fourths of the initially successful cases. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. One focus has been on the use of intra-vitreal antimetabolites to prevent the occurrence of PVR.  相似文献   
59.

Background  

Since the 1980s the Majengo Observational Cohort Study (MOCS) has examined sexually transmitted infections, in particular HIV/AIDS, in a cohort of sex workers in Majengo, an impoverished urban village in Nairobi, Kenya. The MOCS investigators have faced criticism since the women have remained in the sex trade for the duration of their participation in the study, prompting concerns about exploitation. Yet despite these concerns, the cohort has survived for almost 30 years.  相似文献   
60.

Background

The incidence of pseudoaneurysm has increased due to the large number of vascular procedures performed and the widespread use of anticoagulation therapy during procedures. Non-invasive methods for management of pseudoaneurysms comprise of ultrasound guided compression (USGC), thrombin therapy, arterial embolisation and endovascular stent graft insertion. We discuss our experience in the management of fourteen cases of pseudoaneurysms using non surgical techniques.

Methods

During a two year period, fourteen patients presenting with pseudoaneurysms of different regions were treated.

Result

Of the fourteen patients, eleven were iatrogenic and three were attributable to trauma. There were six cases of pseudoaneurysms of the femoral artery following coronary angiography studies. One patient developed pseudoaneurysm of right popliteal artery after external fixation of fracture right tibia and fibula. Three cases of renal artery pseudoaneurysms occurred following percutaneous nephrolithotomy (PCNL). The cases were evaluated using a varying combination of color doppler, multidetector computerised tomography (CT) and angiography. These cases were treated with ultrasound guided compression (USGC), stent graft and coil embolisation. The selection of method was based on the location and size of pseudoaneurysms besides the efficacy of the technique. USGC was performed in seven, of which six were in the femoral artery and one supraorbital. The technique was unsuccessful in three of the seven, wherein stent graft was deployed in the femoral artery. Coil embolisation was utilised in three cases of renal artery pseudoaneurysms following PCNL.

Conclusion

Follow up with color doppler and CT angiography within a week, 6 and 12 months period showed successful regression of pseudoaneurysms in all cases.Key Words: Pseudoaneurysm, Arterial trauma, Ultrasound guided compression, Coil embolisation, Endovascular stent graft  相似文献   
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