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Background

Vaccination of children with 13-valent pneumococcal conjugate vaccine (PCV13) led to declines in vaccine-type pneumococcal nasopharyngeal carriage among adults through indirect effects. In August 2014, PCV13 immunization of all U.S. adults ≥65?years of age was recommended. This study sought to define prevalence and serotype distribution of pneumococcal carriage among adults ≥65?years of age and to describe risk factors for colonization soon after introduction of PCV13 in adults.

Methods

A cross-sectional survey of non-institutionalized U.S. adults ≥65?years of age was conducted in four states in 2015–2016. Demographic information, risk factors for disease, PCV13 vaccination history, and nasopharyngeal (NP) and oropharyngeal (OP) swabs were collected. NP and OP swabs were processed separately and pneumococcal isolates were serotyped by Quellung reaction. Antimicrobial susceptibility of pneumococcal isolates was performed. NP swabs also underwent real-time PCR for pneumococcal detection and serotyping.

Results

Of 2989 participants, 45.3% (1354/2989) had been vaccinated with PCV13. Fifty-five (1.8%) carried pneumococcus (45 identified by culture and 10 by real-time PCR only) and PCV13 serotypes were found in eight (0.3%) participants. Almost half (22/45) of pneumococcal isolates were not susceptible to at least one of the antibiotics tested. Vaccine-type carriage among vaccinated and unvaccinated individuals was similar (0.2% vs. 0.1%, respectively). Respiratory symptoms were associated with higher odds of pneumococcal colonization (adjusted OR: 2.1; 95% CI?=?1.1–3.8).

Conclusions

Pneumococcal carriage among non-institutionalized adults ≥65?years of age was very low. Less than 0.5% of both vaccinated and unvaccinated individuals in our study carried vaccine-type serotypes. Over a decade of PCV vaccination of children likely led to indirect effects in adults. However, given the low vaccine-type carriage rates we observed in an already high PCV13 adult coverage setting, it is difficult to attribute our findings to the direct versus indirect effects of PCV13 on adult carriage.  相似文献   
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Background: Caregivers of stroke survivors often suffer depressive symptoms that interfere with their own health. Early recognition may lead to attenuation of symptoms and better health and well-being for caregivers.

Objective: We examined characteristics of caregivers and stroke survivors associated with caregivers’ depressive symptoms in the early poststroke period.

Methods: We conducted a prospective, longitudinal exploratory observational study with a convenience sample of 63 caregivers of older adult (≥ 65 years) stroke survivors recruited from urban acute-care settings. We enrolled caregivers by 2 weeks poststroke (T1) and revisited them 4 weeks later (T2). Depressive symptoms were measured using the Patient Health Questionnaire-9. A separate unadjusted linear mixed model was computed to explore significant associations between each caregiver or stroke-survivor characteristic and depressive symptoms.

Results: Caregivers, on average, reported mild depressive symptoms at T1 and T2. Each of the following characteristics was independently associated with caregiver depressive symptoms over the first 6 weeks poststroke: caregiver uncertainty (p < 0.001), perceived stress (p < 0.001) but not cortisol levels (p = 0.858 on waking, p = 0.231 evening), coping (p < 0.001), social support (p = 0.006), race (p = 0.022), income (p = 0.001), time spent on care (p = 0.039), and stroke-survivor race (p = 0.033) and functional status (p = 0.003). At T2, caregiver depressive symptoms were correlated with evening cortisol level (p = 0.001).

Conclusions: Caregiver and stroke-survivor characteristics may help identify caregivers at highest risk for early depressive symptoms and guide interventions aimed at their resolution.  相似文献   

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In this review, we explore how to assess potential harm related to neonatal transfusion practice. We consider different sources of information, including passive or active surveillance systems such as registries, observational studies, randomised trials and systematic reviews. Future research directions are discussed.  相似文献   
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Hemorrhage is recognized as a new independent predictor of adverse outcomes following acute myocardial infarction. However, the mechanisms of its effects are less understood. The aim of our study was to probe the downstream impact of hemorrhage towards chronic remodeling, including inflammation, vasodilator function and matrix alterations in an experimental model of hemorrhage. Myocardial hemorrhage was induced in the porcine heart by intracoronary injection of collagenase. Animals (N = 18) were subjected to coronary occlusion followed by reperfusion in three groups (six/group): 8 min ischemia with hemorrhage (+HEM), 45 min infarction with no hemorrhage (I ? HEM) and 45 min infarction with hemorrhage (I + HEM). MRI was performed up to 4 weeks after intervention. Cardiac function, edema (T2, T1), hemorrhage (T2*), vasodilator function (T2 BOLD), infarction and microvascular obstruction (MVO) and partition coefficient (pre‐ and post‐contrast T1) were computed. Hemorrhage was induced only in the +HEM and I + HEM groups on Day 1 (low T2* values). Infarct size was the greatest in the I + HEM group, while the +HEM group showed no observable infarct. MVO was seen only in the I + HEM group, with a 40% occurrence rate. Function was compromised and ventricular volume was enlarged only in the hemorrhage groups and not in the ischemia‐alone group. In the infarct zone, edema and matrix expansion were the greatest in the I + HEM group. In the remote myocardium, T2 elevation and matrix expansion associated with a transient vasodilator dysfunction were observed in the hemorrhage groups but not in the ischemia‐alone group. Our study demonstrates that the introduction of myocardial hemorrhage at reperfusion results in greater myocardial damage, upregulated inflammation, chronic adverse remodeling and remote myocardial alterations beyond the effects of the initial ischemic insult. A systematic understanding of the consequences of hemorrhage will potentially aid in the identification of novel therapeutics for high‐risk patients progressing towards heart failure.  相似文献   
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