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91.
Wire-guided localization (WGL) is the standard of care in the surgical treatment of nonpalpable breast tumors. In this study, we compare the use of a new magnetic marker localization (MaMaLoc) technique to WGL in the treatment of early-stage breast cancer patients. Open-label, single-center, randomized controlled trial comparing MaMaLoc (intervention) to WGL (control) in women with early-stage breast cancer. Primary outcome was surgical usability measured using the System Usability Scale (SUS, 0–100 score). Secondary outcomes were patient reported, clinical, and pathological outcomes such as retrieval rate, operative time, resected specimen weight, margin status, and reoperation rate. Thirty-two patients were analyzed in the MaMaLoc group and 35 in the WGL group. Patient and tumor characteristics were comparable between groups. No in situ complications occurred. Retrieval rate was 100% in both groups. Surgical usability was higher for MaMaLoc: 70.2 ± 8.9 vs. 58.1 ± 9.1, < 0.001. Patients reported higher overall satisfaction with MaMaLoc (median score 5/5) versus WGL (score 4/5), < 0.001. The use of magnetic marker localization (MaMaLoc) for early-stage breast cancer is effective and has higher surgical usability than standard WGL.  相似文献   
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Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.  相似文献   
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BackgroundBacillus Calmette–Guérin (BCG) vaccine provides partial protection against Buruli ulcer caused by Mycobacterium ulcerans in epidemiological studies. This study aimed to quantify M. ulcerans-specific immune responses induced by BCG immunisation.MethodsIntracellular cytokine analysis of in-vitro experiments done 10 weeks after BCG immunisation in 130 Australian infants randomised to one of three BCG vaccine strains given either at birth (BCG-Denmark, BCG-Japan, or BCG-Russia) or at two months of age (BCG-Denmark).ResultsProportions of polyfunctional CD4+ T-cells were higher in M. ulcerans-stimulated compared to unstimulated control samples. These proportions were not influenced by the vaccine strain or timing of the immunisation. The M. ulcerans-specific immune responses showed similar patterns to those observed in M. tuberculosis-stimulated samples, although they were of lower magnitude.ConclusionsOur data show that BCG immunisation induces M. ulcerans-specific immune responses in infants, likely explaining the cross-protective effect observed in epidemiological studies. (ACTRN12608000227392)  相似文献   
96.
《Vaccine》2021,39(18):2537-2544
BackgroundAlthough the efficacy of hepatitis B vaccines among hemodialysis patients has been documented, the long-term persistence of immunogenicity in this population remains largely unknown. We explored the long-term persistence of immunogenicity induced by different hepatitis B vaccine regimens in hemodialysis patients.MethodsIn initial study, we conducted a randomized, multicenter, double-blind, parallel-controlled trial among hemodialysis patients in 13 hospitals in Shanxi Province, China. A total of 352 hemodialysis patients were allocated to receive 3-dose 20 μg (IM20 group) and 3-dose 60 μg (IM60 group) recombinant hepatitis B vaccine at months 0, 1, and 6. Vaccine-induced immune responses were measured at month 7. In this study, the responders (anti-HBs ≥ 10 mIU/mL) were followed up at months 18, 24, 30, 36 and 42, respectively. We used the generalized log-rank test and generalized estimating equations (GEE) to analyze the long-term durability of responses and the kinetics of anti-HBs levels, respectively.ResultsA total of 284 patients were involved in the extended follow-up period. The duration of vaccine-induced response with 75% of patients maintained protective antibody were 12 months and 18 months in the IM20 group and IM60 group, respectively (P = 0.291). The long-term persistent immunogenicity induced by 3-dose 60 μg was more satisfactory than that by 3-dose 20 μg hepatitis B vaccine in patients with hemodialysis duration ≥ five years (P = 0.023). The peak anti-HBs levels in 100–1000 mIU/mL or ≥ 1000 mIU/mL were more likely to maintain long-term protective antibody compared to anti-HBs levels in 10–100 mIU/mL (P < 0.05). The kinetic profile was similar between the two groups (P = 0.334).ConclusionHigh-dose 60 μg hepatitis B vaccine could lead a satisfactory long-term durability of immunogenicity among patients with hemodialysis duration of five years or more. Peak anti-HBs level after vaccination was associated with the long-term persistence of immunogenicity.  相似文献   
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When a new treatment regimen is expected to have comparable or slightly worse efficacy to that of the control regimen but has benefits in other domains such as safety and tolerability, a noninferiority (NI) trial may be appropriate but is fraught with difficulty in justifying an acceptable NI margin that is based on both clinical and statistical input. To overcome this, we propose to utilize composite risk‐benefit outcomes that combine elements from domains of importance (eg, efficacy, safety, and tolerability). The composite outcome itself may be analyzed using a superiority framework, or it can be used as a tool at the design stage of a NI trial for selecting an NI margin for efficacy that balances changes in risks and benefits. In the latter case, the choice of NI margin may be based on a novel quantity called the maximum allowable decrease in efficacy (MADE), defined as the marginal difference in efficacy between arms that would yield a null treatment effect for the composite outcome given an assumed distribution for the composite outcome. We observe that MADE: (1) is larger when the safety improvement for the experimental arm is larger, (2) depends on the association between the efficacy and safety outcomes, and (3) depends on the control arm efficacy rate. We use a numerical example for power comparisons between a superiority test for the composite outcome vs a noninferiority test for efficacy using the MADE as the NI margin, and apply the methods to a TB treatment trial.  相似文献   
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Summary There is very suggestive evidence for a role of serotonin release from platelets in the mechanisms for platelet aggregation, arterial thrombosis, and arterial spasm. These effects are mediated via the 5HT2 receptor and are specifically antagonized by ketanserin. The recently published PACK study was a randomized controlled trial of the effects of ketanserin in patients with intermittent claudication. The purpose of the trial was to discover whether ketanserin treatment would reduce the incidence of atherosclerotic complications such as myocardial infarction or stroke. An unexpected adverse interaction between ketanserin and potassium-losing diuretics was observed, causing an excess of deaths in the group taking this combination of drugs. The intention-to-treat analysis showed no overall difference between ketanserin and placebo in terms of cardiovascular complications. Withdrawal of patients taking potassium-losing diuretics left insufficient numbers of patients in the study to answer the original question. However, the on-treatment analysis excluding those taking the combination suggested strongly, although did not prove, that ketanserin reduced thrombotic episodes by about 25%. It is concluded that the risks of interactions between many drugs and potassium-losing diuretics make the use of the latter undesirable. Further studies on ketanserin, possibly combined with thromboxane A2 inhibitors, seem highly desirable.  相似文献   
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