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141.
142.
Left internal mammary artery (LIMA)-to-pulmonary artery fistulae rarely develop after coronary artery bypass grafting. Fewer than 30 cases of these fistulae have been reported since 1947. Nevertheless, this entity should be considered as a cause of recurrent angina after bypass surgery, in the absence of other causes. We present the case of a 67-year-old man with cardiac symptoms in whom multiple LIMA-to-pulmonary artery fistulae were found, 15 years after he had undergone coronary artery bypass grafting. The diagnosis was confirmed by means of coronary angiography with selective catheterization of the LIMA and by computed tomographic angiography of the heart. The patient underwent reoperative 2-vessel coronary artery bypass grafting and ligation of multiple fistulae; 16 months postoperatively, he was asymptomatic and doing well. In addition to reporting this case, we discuss relevant diagnostic and treatment considerations.Key words: Arteriovenous malformations/physiopathology, coronary artery bypass/adverse effects, fistula/etiology, internal mammary-coronary artery anastomosis/adverse effects, mammary arteries/surgery, myocardial ischemia/etiology, pulmonary artery/surgery, vascular fistula/complications/etiology/surgeryAs a bypass-graft conduit to the left anterior descending coronary artery (LAD), the left internal mammary artery (LIMA) is the vessel of choice because of its proven longevity and long-term patency. The formation of a LIMA-to-pulmonary artery (PA) fistula after coronary artery bypass grafting (CABG) is a rare complication: fewer than 30 reports have appeared in the medical literature.1 We report a case of multiple LIMA-to-PA fistulae that we found 15 years after a patient had undergone CABG.  相似文献   
143.
Epigenetic information is available from contemporary organisms, but is difficult to track back in evolutionary time. Here, we show that genome-wide epigenetic information can be gathered directly from next-generation sequence reads of DNA isolated from ancient remains. Using the genome sequence data generated from hair shafts of a 4000-yr-old Paleo-Eskimo belonging to the Saqqaq culture, we generate the first ancient nucleosome map coupled with a genome-wide survey of cytosine methylation levels. The validity of both nucleosome map and methylation levels were confirmed by the recovery of the expected signals at promoter regions, exon/intron boundaries, and CTCF sites. The top-scoring nucleosome calls revealed distinct DNA positioning biases, attesting to nucleotide-level accuracy. The ancient methylation levels exhibited high conservation over time, clustering closely with modern hair tissues. Using ancient methylation information, we estimated the age at death of the Saqqaq individual and illustrate how epigenetic information can be used to infer ancient gene expression. Similar epigenetic signatures were found in other fossil material, such as 110,000- to 130,000-yr-old bones, supporting the contention that ancient epigenomic information can be reconstructed from a deep past. Our findings lay the foundation for extracting epigenomic information from ancient samples, allowing shifts in epialleles to be tracked through evolutionary time, as well as providing an original window into modern epigenomics.Ancient DNA research started in the mid-1980s with the successful cloning and sequencing of a short mitochondrial DNA fragment from the quagga zebra, a species that became extinct in the early 20th century (Higuchi et al. 1984). Soon after, the invention of PCR unlocked access to this fragmented and degraded DNA material (Pääbo 1989), making it possible to amplify short gene markers of interest and compare their sequence to that from extant organisms. This illuminated a range of topics ranging from the reconstruction of the evolutionary origins of several now-extinct iconic mammals (Orlando et al. 2003; Krause et al. 2006), the evaluation of the possible role played by major past climatic changes in driving mega-fauna extinctions (Shapiro et al. 2004; Campos et al. 2010; Lorenzen et al. 2011), to the identification of the pathogens responsible for massive historical outbreaks (Taubenberger et al. 1997).However, before the advent of next-generation sequencing (NGS) platforms, the amount of ancient sequence information one had access to was limited to several tens of thousands of nucleotides at best (Noonan et al. 2005, 2006), and until very recently, sequencing whole ancient mitochondrial genomes was considered a major achievement (Cooper et al. 2001; Krause et al. 2006). Parallel sequencing of millions to billions of short DNA fragments has revolutionized ancient DNA research, and today a series of ancient genomes has been reconstructed from humans (Rasmussen et al. 2010, 2011; Keller et al. 2012; Raghavan et al. 2013), archaic hominins (Green et al. 2010; Reich et al. 2010; Meyer et al. 2012), the woolly mammoth (Miller et al. 2008), and several microbial pathogens (Bos et al. 2011; Martin et al. 2013; Schuenemann et al. 2013; Yoshida et al. 2013). Those mainly date back to recent historical periods or the Late Pleistocene, but most recently, the characterization of a 560,000- to 780,000-yr-old horse draft genome revealed that genomic information could be retrieved over much longer evolutionary time scales, probably up until the last million years (Orlando et al. 2013).Ancient genomes have provided important new insights into human evolution and dispersals (Rasmussen et al. 2010, 2011; Keller et al. 2012; Raghavan et al. 2013), revealing an admixture between contemporary human ancestors and archaic hominins (Green et al. 2010; Reich et al. 2010; Meyer et al. 2012) and multiple early human expansions into both Asia and North America (Rasmussen et al. 2010, 2011). The information gained from these samples has largely been limited to nucleotide polymorphisms. Unlike mutations, epigenetic modifications do not alter the underlying DNA sequence, but can be inherited across cell divisions and from parents to offspring and can control gene expression by reshaping cytosine methylation landscapes, nucleosome organization, and histone modification patterns. The range of biological processes that depend on some level of epigenetic regulation is diverse and includes imprinting (Bird 2002), transposition (Hollister and Gaut 2009), cell differentiation (Meissner et al. 2008), and cancer (Teschendorff et al. 2011). In this study, we use the Saqqaq genome that was retrieved from an ∼4000-yr-old tuft of hair of a Paleo-Eskimo from Greenland and sequenced to an average depth of 20× (Rasmussen et al. 2010). We demonstrate that NGS data can be used in the absence of bisulfite or further experimental treatment to directly infer genome-wide nucleosome organization and regional methylation levels, thereby providing the first survey of an ancient epigenome.  相似文献   
144.

Background

Changes in resident duty hours in Europe and North America have had a major impact on the internal organizational dynamics of health care organizations. This paper examines, and assesses the impact of, organizational interventions that were a direct response to these duty hour reforms.

Methods

The academic literature was searched through the SCOPUS database using the search terms “resident duty hours” and “European Working Time Directive,” together with terms related to organizational factors. The search was limited to English-language literature published between January 2003 and January 2012. Studies were included if they reported an organizational intervention and measured an organizational outcome.

Results

Twenty-five articles were included from the United States (n = 18), the United Kingdom (n = 5), Hong Kong (n = 1), and Australia (n = 1). They all described single-site projects; the majority used post-intervention surveys (n = 15) and audit techniques (n = 4). The studies assessed organizational measures, including relationships among staff, work satisfaction, continuity of care, workflow, compliance, workload, and cost. Interventions included using new technologies to improve handovers and communications, changing staff mixes, and introducing new shift structures, all of which had varying effects on the organizational measures listed previously.

Conclusions

Little research has assessed the organizational impact of duty hour reforms; however, the literature reviewed demonstrates that many organizations are using new technologies, new personnel, and revised and innovative shift structures to compensate for reduced resident coverage and to decrease the risk of limited continuity of care. Future research in this area should focus on both micro (e.g., use of technology, shift changes, staff mix) and macro (e.g., culture, leadership support) organizational aspects to aid in our understanding of how best to respond to these duty hour reforms.
  相似文献   
145.
BRIEF REPORT The activity of natural killer (NK) cells is partially regulated by killer cell immunoglobulin-like receptors (KIRs) interacting with human leukocyte antigen C (HLA-C) ligands.1 The ligands of several inhibitory (2DL and 3DL) and activating (2DS and 3DS) KIR have been described.  相似文献   
146.

Background

Auditory neural myelination (ANM) as evaluated by auditory brainstem evoked response (ABR) during the neonatal period has been used as a surrogate outcome for long-term neurodevelopment. The validity of ANM as a surrogate outcome for long-term neurodevelopment has not been well studied.

Aim

Evaluate the association of ABR I–V interpeak latency (IPL), an index of ANM, at 35 week postmenstrual age (PMA) with language outcome at 3 years of age.

Design

Prospective study.

Subjects

24–33 week gestational age (GA) infants were eligible if they did not meet exclusion criteria: craniofacial malformation, chromosomal disorders, deafness, auditory dys-synchrony, TORCH infection, or non-English speaking parents. Infants with malignancy, head injury, encephalopathy, meningitis, blindness, or who died or relocated were also excluded.

Outcome measures

ABRs were performed at 35 week PMA using 80 dB nHL and I–V IPL (ms) measured. Auditory Comprehension (AC) and Expressive Communication (EC) were evaluated by a speech-language pathologist at 3 years of age using Preschool Language Scale.

Results

Eighty infants were studied. The mean GA and birth weight of infants were 29.2 weeks and 1336 g, respectively. There was association of worse ear I–V IPL and better ear I–V IPL with AC (Coefficient − 5.4, 95% CI: − 9.8 to − 0.9 and Coefficient − 5.5, 95% CI: − 10  to−0.9, respectively) and EC (Coefficient − 5.6, 95% CI: − 9.5  to−1.8 and Coefficient − 6.7, 95% CI: − 10.6  to−2.7, respectively) after controlling for confounders.

Conclusion

The neonatal I–V IPL is a predictor of language development at 3 years of age in preterms.  相似文献   
147.

Introduction

Radiographic images may lead to misinterpretations of lesions of endodontic and nonendodontic origin. This report describes a case of a 10-year follow-up of a calcifying odontogenic cyst (COC) in the periapical region of a vital maxillary central incisor in a 9-year-old boy.

Methods

The patient revealed a history of a swelling in the periapical area of tooth #9. The patient denied any dental trauma or history of pain. Clinical examination revealed no mobility, but there was discrete discomfort when horizontal pressure was applied. Pulp vitality was present in all maxillary anterior teeth. Radiographs revealed an oval radiolucent lesion in the periapical region of maxillary central incisor. The therapeutic option was enucleation of the periapical lesion and histologic examination of the specimen. Microscopic findings suggested the diagnosis of a COC.

Results

At a follow-up visit 10 years after surgery, panoramic and periapical radiographs showed new bone formation; the patient did not have any pain, and pulp vitality was maintained in all teeth in this area.

Conclusions

A COC should be part of the differential diagnosis of other jaw lesions, such as apical periodontitis. The definitive diagnosis of a COC can only be made after microscopic evaluation of the specimen. The follow-up is a helpful reference because it confirms the survival of pulp tissue and no recurrence of the COC.  相似文献   
148.
149.
In recent years, implantology has made significant progress, as it has now become a safe and predictable practice. The development of new geometries, primary and secondary, of new surfaces and alloys, has made this possible. The purpose of this review is to analyze the different alloys present on the market, such as that in zirconia, and evaluate their clinical differences with those most commonly used, such as those in grade IV titanium. The review, conducted on major scientific databases such as Scopus, PubMed, Web of Science and MDPI yielded a startling number of 305 results. After the application of the filters and the evaluation of the results in the review, only 10 Randomized Clinical Trials (RCTs) were included. Multiple outcomes were considered, such as Marginal Bone Level (MBL), Bleeding on Probing (BoP), Survival Rate, Success Rate and parameters related to aesthetic and prosthetic factors. There are currently no statistically significant differences between the use of zirconia implants and titanium implants, neither for fixed prosthetic restorations nor for overdenture restorations. Only the cases reported complain about the rigidity and, therefore, the possibility of fracture of the zirconium. Certainly the continuous improvement in these materials will ensure that they could be used safely while maintaining their high aesthetic performance.  相似文献   
150.
BackgroundEpicardial adipose tissue (EAT) is increased in comorbidities common in heart failure (HF). In this sense, EAT could potentially mediate effects that lead to an impaired cardiac function.ObjectivesThis meta-analysis aims to investigate if the amount of EAT in all-types of HF and each HF phenotype is significantly different from control patients.MethodsThis meta-analysis followed the Meta-analysis Of Observational Studies in Epidemiology guidelines. The search was performed in the MEDLINE, Embase, and Lilacs databases until November 2020. Two authors performed screening, data extraction, and quality assessment. A p-value <0.05 was defined as statistically significant.ResultsEight observational studies were included, comprehending 1,248 patients in total, from which 574 were controls, 415 had HF with reduced ejection fraction (HFrEF) and 259 had HF with mid-range or preserved ejection fraction (HFmrEF or HFpEF). The amount of EAT was not different between all types of HF and the control group (SMD = -0.66, 95% CI: -1.54 to 0.23, p =0.14). Analyzing each HF phenotype separately, patients with HFrEF had a reduced EAT when compared to the controls (SMD= -1.27, 95% CI: - 1.87 to -0.67, p <0.0001), while patients with HFmrEF or HFpEF showed an increased EAT when compared to controls (SMD= 1.24, 95% CI: 0.99 to 1.50, p <0.0001).ConclusionThe amount of EAT was not significantly different between all types of HF and the control group. In patients with HFrEF, the EAT volume was reduced, whereas in HFpEF and HFmrEF, the amount of EAT was significantly increased. PROSPERO registration number: CRD42019134441.  相似文献   
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