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Acute graft-versus-host disease (aGVHD) remains a barrier to the success of allogeneic hematopoietic stem cell transplantation. In mice, studies have demonstrated that donor conventional T cells traffic into host secondary lymphoid tissues early after transplant, and that this process is critical for the development of disease. As a result, the measurement of cellular proliferation within lymphoid sites early after transplant might be a useful approach for predicting aGVHD in humans. 18F-3′-deoxy-3′-fluorothymidine (FLT) positron emission tomography (PET) imaging has recently emerged as a functional imaging modality in oncology patients. FLT, a thymidine analog, is incorporated into replicating DNA and is thus an indirect marker of cellular proliferation. Here we report that FLT PET imaging can differentiate mice receiving alloreactive T cells and destined to develop lethal aGVHD from control mice. Mice receiving allogeneic T cells demonstrated a stronger FLT signal within the peripheral lymph nodes compared with control mice at all time points after transplant. In addition, allogeneic T cell recipients transiently demonstrated stronger FLT uptake within the spleen. Importantly, these differences were apparent before the development of clinical disease. In contrast, the FLT signal within the host bowel, an important aGVHD target organ, was more variable after transplant and was not consistently different between aGVHD mice and control mice. Collectively, these findings suggest that the imaging of patient lymphoid sites using existing FLT PET technology might be useful for predicting aGVHD in the clinical setting.  相似文献   
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Epstein‐Barr virus detection using nasopharyngeal swabs has been suggested as a potential screening test that could improve the specificity of current EBV‐based serological assays. However, application requires insertion of the swab deep into the nasopharynx, a procedure not amenable to non‐clinic screening. We reasoned that swabbing the more easily accessible nasal cavity might provide an appealing alternative for NPC detection. Patients > 18 years of age diagnosed with histologically confirmed NPC were recruited from the Otolaryngology Department at the National Taiwan University Hospital. ENT clinicians collected both nasal and nasopharyngeal swabs. EBV DNA and cellular beta‐globulin DNA were quantified using quantitative PCR targeting a highly‐conserved region of the BKRF1 gene. EBV DNA was detectable (non‐zero) in all 34 nasopharyngeal swabs and above the positivity threshold of 1666 EBV copies in 30 (88.2%) patients. EBV DNA was detectable in 50% of 34 nasal swabs and above the positivity threshold in four (11.8%) patients. Average EBV DNA levels were >3‐fold higher (P < 0.001) in nasopharyngeal compared to nasal swabs. Among the 17 NPC patients with detectable EBV DNA in both swab types, we observed correlation (P < 0.01) between EBV DNA measurements. Our data represent the first evaluation of EBV DNA collected from nasal swabs. Given current EBV DNA amplification techniques, nasopharyngeal swabs remain more sensitive than nasal swabs for NPC detection.  相似文献   
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The ubiquitous nature of plastics has raised concerns pertaining to continuous exposure to plastic polymers and human health risks. Of particular concern is the use of endocrine-disrupting chemicals in plastic production, including di(2-ethylhexyl)phthalate (DEHP) and bisphenol A (BPA). Widespread and continuous exposure to DEHP and BPA occurs through dietary intake, inhalation, dermal and intravenous exposure via consumer products and medical devices. This article reviews the literature examining the relationship between DEHP and BPA exposure and cardiac toxicity. In vitro and in vivo experimental reports are outlined, as well as epidemiological studies which examine the association between these chemicals and cardiovascular outcomes. Gaps in our current knowledge are also discussed, along with future investigative endeavors that may help resolve whether DEHP and/or BPA exposure has a negative impact on cardiovascular physiology.  相似文献   
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This article demonstrates how an action learning approach was used to implement and develop a practice learning team in a clinical setting. The team linked a higher education institution and a practice setting to improve the placement experience for nursing students and practice mentors. The practice learning team has developed initiatives to improve mentoring for nursing students.  相似文献   
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Background

One of the proposed advantages of laparoscopic inguinal hernia repair is complimentary inspection of the contralateral side and possible detection of occult hernias. Incidence of occult contralateral hernias is as high as 50 %. The natural course of such occult defects is unknown and therefore operative rationale is lacking. This study was designed to analyze the incidence of occult contralateral inguinal hernias and its natural course.

Methods

A total of 1,681 patients were diagnosed preoperatively with unilateral inguinal hernia. None of these patients had complaints of the contralateral side preoperatively. All patients underwent laparoscopic inguinal hernia transabdominal preperitoneal (TAPP) repair. Operative details were analyzed retrospectively. Patients with occult contralateral defects were identified and tracked. Patients with an evident occult hernia received immediate repair. Patients with a smaller beginning or incipient hernia were followed.

Results

In 218 (13 %) patients, an occult hernia was found at the contralateral side during preoperative exploration. In 129 (8 %) patients, an occult true hernia was found. In 89 (5 %) patients, an occult incipient hernia was found. An incipient hernia was defined as a beginning hernia. All patients with an incipient hernia were followed. The mean follow-up was 112 (range 16–218) months. Twenty-eight (32 %) patients were lost to follow-up. In the 61 remaining patients, 13 (21 %) occult incipient hernias became symptomatic requiring repair. The mean time between primary repair and development of a symptomatic hernia on the contralateral side was 88 (range 24–210) months.

Conclusions

This study shows that the incidence of occult contralateral hernias is 13 % during TAPP repair of unilateral diagnosed inguinal hernias. In 5 % of the cases, the occult hernia consisted of a beginning hernia. Eventually, one of five will become symptomatic and require repair. These outcomes support immediate repair of occult defects, no matter its size.  相似文献   
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Since 2012, H7N3 highly pathogenic avian influenza (HPAI) has produced negative economic and animal welfare impacts on poultry in central Mexico. In the present study, chickens were vaccinated with two different recombinant fowlpox virus vaccines (rFPV-H7/3002 with 2015 H7 hemagglutinin [HA] gene insert, and rFPV-H7/2155 with 2002 H7 HA gene insert), and were then challenged three weeks later with H7N3 HPAI virus (A/chicken/Jalisco/CPA-37905/2015). The rFPV-H7/3002 vaccine conferred 100% protection against mortality and morbidity, and significantly reduced virus shed titers from the respiratory and gastrointestinal tracts. In contrast, 100% of sham and rFPV-H7/2155 vaccinated birds shed virus at higher titers and died within 4?days. Pre- (15/20) and post- (20/20) challenge serum of birds vaccinated with rFPV-H7/3002 had antibodies detectable by hemagglutination inhibition (HI) assay using challenge virus antigen. However, only a few birds (3/20) in the rFPV-H7/2155 vaccinated group had antibodies that reacted against the challenge strain but all birds had antibodies that reacted against the homologous vaccine antigen (A/turkey/Virginia/SEP-66/2002) (20/20). One possible explanation for differences in vaccines efficacy is the antigenic drift between circulating viruses and vaccines. Molecular analysis demonstrated that the Mexican H7N3 strains have continued to rapidly evolve since 2012. In addition, we identified in silico three potential new N-glycosylation sites on the globular head of the H7 HA of A/chicken/Jalisco/CPA-37905/2015 challenge virus, which were absent in 2012 H7N3 outbreak virus. Our results suggested that mutations in the HA antigenic sites including increased glycosylation sites, accumulated in the new circulating Mexican H7 HPAIV strains, altered the recognition of neutralizing antibodies from the older vaccine strain rFPV-H7/2155. Therefore, the protective efficacy of novel rFPV-H7/3002 against recent outbreak Mexican H7N3 HPAIV confirms the importance of frequent updating of vaccines seed strains for long-term effective control of H7 HPAI virus.  相似文献   
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