1,663 research outputs found
Hybridization in human evolution: Insights from other organisms
During the late Pleistocene, isolated lineages of hominins exchanged genes thus influencing genomic variation in humans in both the past and present. However, the dynamics of this genetic exchange and associated phenotypic consequences through time remain poorly understood. Gene exchange across divergent lineages can result in myriad outcomes arising from these dynamics and the environmental conditions under which it occurs. Here we draw from our collective research across various organisms, illustrating some of the ways in which gene exchange can structure genomic/phenotypic diversity within/among species. We present a range of examples relevant to questions about the evolution of hominins. These examples are not meant to be exhaustive, but rather illustrative of the diverse evolutionary causes/consequences of hybridization, highlighting potential drivers of human evolution in the context of hybridization including: influences on adaptive evolution, climate change, developmental systems, sex-differences in behavior, Haldane’s rule and the large X-effect, and transgressive phenotypic variation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151330/1/evan21787.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151330/2/evan21787_am.pd
Lacrimal Gland Involvement in Blepharophimosis-Ptosis-Epicanthus Inversus Syndrome
PURPOSE:
To describe the involvement of the lacrimal gland (LG) in blepharophimosis-ptosis-epicanthus inversus syndrome (BPES).
DESIGN:
Observational, cross-sectional study.
PARTICIPANTS:
Twenty-one patients with BPES (10 female, 11 male) aged on average 15 years (range, 2-39 years), from 3 Brazilian medical centers and 1 Portuguese medical center.
METHODS:
Patients had their ocular surface evaluated with slit-lamp biomicroscopy, and tear production quantified with the Schirmer test I. The LG volumes were measured on computed tomography (CT) scans in the BPES sample and in a group of age-matched subjects imaged for nonorbital diseases. Sixteen patients were screened for mutations in the FOXL2 gene.
MAIN OUTCOME MEASURES:
Lacrimal meniscus height, Schirmer test I, presence of superficial punctate keratopathy (SPK), LG volume, and molecular analysis of the FOXL2 gene.
RESULTS:
Absence of LG was detected bilaterally in 9 patients (42.8%) and unilaterally in 2 patients (9.5%). When considering only patients with measurable LG, the median volume was 0.22 cm3 in the right eye (range, 0.06-0.36 cm3) and 0.24 cm3 in the left eye (range, 0.08-0.34 cm3). These values were significantly lower than those for the age-matched controls (median = 0.54 right eye and 0.53 left eye; P < 0.05). There was a significant association between deficiency of tear production and LG volume reduction and agenesis. Molecular analysis of the FOXL2 gene revealed the presence of 8 distinct mutations, 4 of them novel ones. A significant reduction of LG size or agenesis was associated with mutations affecting protein size (due to underlying changes in the stop codon location) or the DNA-binding forkhead domain (Fisher exact test, P = 0.021). In 3 probands, the underlying genetic defect was not found.
CONCLUSIONS:
This is the first study reporting LG volumes in BPES, describing a significant number of patients with LG agenesis. The association between alacrima and BPES is not incidental, and a thorough evaluation of tear production is recommended especially if ptosis surgery is planned.info:eu-repo/semantics/acceptedVersio
Echocardiographic and hemodynamic determinants of right coronary artery flow reserve and phasic flow pattern in advanced non-ischemic cardiomyopathy
<p>Abstract</p> <p>Background</p> <p>In patients with advanced non-ischemic cardiomyopathy (NIC), right-sided cardiac disturbances has prognostic implications. Right coronary artery (RCA) flow pattern and flow reserve (CFR) are not well known in this setting. The purpose of this study was to assess, in human advanced NIC, the RCA phasic flow pattern and CFR, also under right-sided cardiac disturbances, and compare with left coronary circulation. As well as to investigate any correlation between the cardiac structural, mechanical and hemodynamic parameters with RCA phasic flow pattern or CFR.</p> <p>Methods</p> <p>Twenty four patients with dilated severe NIC were evaluated non-invasively, even by echocardiography, and also by cardiac catheterization, inclusive with Swan-Ganz catheter. Intracoronary Doppler (Flowire) data was obtained in RCA and left anterior descendent coronary artery (LAD) before and after adenosine. Resting RCA phasic pattern (diastolic/systolic) was compared between subgroups with and without pulmonary hypertension, and with and without right ventricular (RV) dysfunction; and also with LAD. RCA-CFR was compared with LAD, as well as in those subgroups. Pearson's correlation analysis was accomplished among echocardiographic (including LV fractional shortening, mass index, end systolic wall stress) more hemodynamic parameters with RCA phasic flow pattern or RCA-CFR.</p> <p>Results</p> <p>LV fractional shortening and end diastolic diameter were 15.3 ± 3.5 % and 69.4 ± 12.2 mm. Resting RCA phasic pattern had no difference comparing subgroups with vs. without pulmonary hypertension (1.45 vs. 1.29, p = NS) either with vs. without RV dysfunction (1.47 vs. 1.23, p = NS); RCA vs. LAD was 1.35 vs. 2.85 (p < 0.001). It had no significant correlation among any cardiac mechanical or hemodynamic parameter with RCA-CFR or RCA flow pattern. RCA-CFR had no difference compared with LAD (3.38 vs. 3.34, p = NS), as well as in pulmonary hypertension (3.09 vs. 3.10, p = NS) either in RV dysfunction (3.06 vs. 3.22, p = NS) subgroups. </p> <p>Conclusion</p> <p>In patients with chronic advanced NIC, RCA phasic flow pattern has a mild diastolic predominance, less marked than in LAD, with no effects from pulmonary artery hypertension or RV dysfunction. There is no significant correlation between any cardiac mechanical-structural or hemodynamic parameter with RCA-CFR or RCA phasic flow pattern. RCA flow reserve is still similar to LAD, independently of those right-sided cardiac disturbances.</p
Influence of diabetes mellitus on the mineralization ability of two endodontic materials
Evaluation of MCM-2 Expression in TMA Cervical Specimens
Background:Minichromosome maintenance proteins (MCM) are highly expressed in actively replicating cells. The need for
biological markers for cervical carcinoma and its precursor lesions is emerging. Our main aim was to determine the
immunohistochemical expression of MCM-2 in HIV-positive and -negative dysplastic cervical specimens.
Methods:Immunohistochemical analysis of MCM-2 was performed in a total of 352 cervical TMA specimens of normal
control, low-grade CIN, high-grade CIN and invasive tumor. 38 specimens were from HIV-positive women. A receiver
operating characteristic (ROC) curve was constructed to determine the best cutoff to diagnose high-grade CIN and invasive
cervical cancer.
Results:In the progression from normal epithelium to high-grade CIN and invasive tumor we found significant differences
in the MCM-2 expression (p,0.05). Based on the ROC curve of 80% with an area under the curve (AUC) of 0.78, expression of
MCM-2 to diagnose high-grade CIN and invasive tumor resulted in sensitivity of 81%, specificity of 66%, a positive predictive
value (PPV) of 86% and a negative predictive value (NPV) of 57%. HIV-positive cervices revealed a decreasing expression of
MCM-2 in both LGCIN and HGCIN compared with HIV-negative specimens (p,0.0001).
Conclusions:The present study suggests that immunohistochemical MCM-2 may not be a promising biomarker for
diagnosing high-grade CIN and invasive cance
Double-chambered right ventricle in an adult patient diagnosed by transthoracic echocardiography
BACKGROUND: Double-chambered right ventricle is a rare congenital disease frequently misdiagnosed in the adult patient. An anomalous muscle band divides the right ventricle in two cavities causing variable degree of obstruction. Although echocardiography is considered a useful method for the diagnosis of this pathology in children, it has been recognized the transthoracic scanning limitation in adults. CASE PRESENTATION: A 29 year-old patient with double-chambered right ventricle presenting mild exercise intolerance referred for follow up of a known ventricular septal defect in whom a complete diagnosis was obtained based only on transthoracic two dimensional echocardiography without the needing of cardiac catheterization. CONCLUSION: Based on non invasive echocardiographic diagnosis, patient was referred to surgical correction, which was completely successful
Characterization of peri-infarct zone by CMR is a robust predictor of major adverse events and is strongly associated with systemic inflammatory response post-myocardial infarction
[No abstract available
Effect of different finishing and polishing techniques on the surface roughness of microfilled, hybrid and packable composite resins
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