Sperm Morphology in Two House Mouse Subspecies: Do Wild-Derived Strains and Wild Mice Tell the Same Story?

<div><p>Being subject to intense post-copulatory selection, sperm size is a principal determining component of male fitness. Although previous studies have presented comparative sperm size data at higher taxonomic levels, information on the evolution of sperm size within species is generally lacking. Here, we studied two house mouse subspecies, <i>Mus musculus musculus</i> and <i>Mus musculus domesticus</i>, which undergo incipient speciation. We measured four sperm dimensions from cauda epididymis smears of 28 wild-caught mice of both subspecies. As inbred mouse strains are frequently used as proxies for exploring evolutionary processes, we further studied four wild-derived inbred strains from each subspecies. The subspecies differed significantly in terms of sperm head length and midpiece length, and these differences were consistent for wild mice and wild-derived strains pooled over genomes. When the inbred strains were analyzed individually, however, their strain-specific values were in some cases significantly shifted from subspecies-specific values derived from wild mice. We conclude that: (1) the size of sperm components differ in the two house mouse subspecies studied, and that (2) wild-derived strains reflect this natural polymorphism, serving as a potential tool to identify the genetic variation driving these evolutionary processes. Nevertheless, we suggest that more strains should be used in future experiments to account for natural variation and to avoid confounding results due to reduced variability and/or founder effect in the individual strains.</p></div

Schema of mouse sperm component measurements.

<p>Measures of sperm midpiece length and tail length are highlighted in yellow and red. Sperm head length and width measurements are represented by dashed lines.</p

Position and genotypes of wild house mice and two Mmd-derived strains: SCHEST and SIT.

<p>Subspecific affiliations of the six remaining WDS were known <i>a priori</i> (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115669#s2" target="_blank">Material and Method</a>).</p><p>Position and genotypes of wild house mice and two Mmd-derived strains: SCHEST and SIT.</p

Differences between Mmd and Mmm in sperm component size.

<p>Sperm head length (A), sperm head width (B), midpiece length (C), and tail length (D). Individual wild-derived strains are marked separately on the left side of the graphs while subspecies-specific strains are put together on the right side of the graphs. The same upper-case letters indicate similarity of sperm components between subspecies and strains in the Tukey <i>post hoc</i> test comparison. Error bars represent 95% confidence intervals.</p

Scatter-plot of sperm head length and midpiece length for all individual males analyzed.

<p>Mmd-specific mice are shown in blue and Mmm-specific mice in red.</p

Anticoagulation risk assessment for patients with non-valvular atrial fibrillation and venous thromboembolism: A clinical review.

Non-valvular atrial fibrillation and venous thromboembolism anticoagulation risk assessment tools have been increasingly utilized to guide implementation and duration of anticoagulant therapy. Anticoagulation significantly reduces stroke and recurrent venous thromboembolism risk, but comes at the cost of increased risk of major and clinically relevant non-major bleeding. The decision for anticoagulation in high-risk patients is complicated by the fact that many risk factors associated with increased thromboembolic risk are simultaneously associated with increased bleeding risk. Traditional risk assessment tools rely heavily on age, sex, and presence of cardiovascular comorbidities, with newer tools additionally taking into account changes in risk factors over time and novel biomarkers to facilitate more personalized risk assessment. These tools may help counsel and inform patients about the risks and benefits of starting or continuing anticoagulant therapy and can identify patients who may benefit from more careful management. Although the ability to predict anticoagulant-associated hemorrhagic risk is modest, ischemic and bleeding risk scores have been shown to add significant value to therapeutic management decisions. Ultimately, further work is needed to optimally implement accurate and actionable risk stratification into clinical practice

Discriminant analysis of sperm size components calculated separately for wild mice and both wild and inbred mice.

<p>Number of mice in lines was obtained via genetic analysis; mice in columns were assigned by discriminant analysis.</p><p>Discriminant analysis of sperm size components calculated separately for wild mice and both wild and inbred mice.</p

Mean values and respective standard errors (SE) of sperm component size for each subspecies and strain (scale in µm).

<p>*In wild mice, age ranges are replaced by number of days spent in captivity.</p><p>Mean values and respective standard errors (SE) of sperm component size for each subspecies and strain (scale in µm).</p

Anomalous Origin of the Right Coronary Artery Causing Myocardial Ischemia: A Case for a Multimodality Imaging Approach

A 46-year-old man was admitted with non-ST elevation myocardial infarction and newly diagnosed acutely decompensated heart failure. Echocardiogram demonstrated left ventricular ejection fraction of 30% with basal inferior and inferolateral akinesis. Coronary angiography showed mild diffuse coronary artery disease and an anomalous right coronary artery arising from the left coronary cusp. Further imaging was consistent with ischemia in the right coronary distribution. Etiology of ischemia was thought to be the anomalous right coronary artery, and surgical unroofing of the right coronary ostium was performed. Here, we report a multimodality imaging approach, including cardiac magnetic resonance, cardiac computed tomographic angiography, and single-photon emission computed tomography, to support the diagnosis and management of a patient with anomalous right coronary artery arising from the left coronary cusp

Assessment of coronary artery calcium scoring to guide statin therapy allocation according to risk-enhancing factors: The multi-ethnic study of atherosclerosis

Importance: The 2018 American Heart Association/American College of Cardiology Guideline on the Management of Blood Cholesterol recommends the use of risk-enhancing factor assessment and the selective use of coronary artery calcium (CAC) scoring to guide the allocation of statin therapy among individuals with an intermediate risk of atherosclerotic cardiovascular disease (ASCVD).Objective: To examine the association between risk-enhancing factors and incident ASCVD by CAC burden among those at intermediate risk of ASCVD.Design, setting, and participants: The Multi-Ethnic Study of Atherosclerosis is a multicenter population-based prospective cross-sectional study conducted in the US. Baseline data for the present study were collected between July 15, 2000, and July 14, 2002, and follow-up for incident ASCVD events was ascertained through August 20, 2015. Participants were aged 45 to 75 years with no clinical ASCVD or diabetes at baseline, were at intermediate risk of ASCVD (≥7.5% to \u3c20.0%), and had a low-density lipoprotein cholesterol level of 70 to 189 mg/dL.Exposures: Family history of premature ASCVD, premature menopause, metabolic syndrome, chronic kidney disease, lipid and inflammatory biomarkers, and low ankle-brachial index.Main outcomes and measures: Incident ASCVD over a median follow-up of 12.0 years.Results: A total of 1688 participants (mean [SD] age, 65 [6] years; 976 men [57.8%]). Of those, 648 individuals (38.4%) were White, 562 (33.3%) were Black, 305 (18.1%) were Hispanic, and 173 (10.2%) were Chinese American. A total of 722 participants (42.8%) had a CAC score of 0. Among those with 1 to 2 risk-enhancing factors vs those with 3 or more risk-enhancing factors, the prevalence of a CAC score of 0 was 45.7% vs 40.3%, respectively. Over a median follow-up of 12.0 years (interquartile range [IQR], 11.5-12.6 years), the unadjusted incidence rate of ASCVD among those with a CAC score of 0 was less than 7.5 events per 1000 person-years for all individual risk-enhancing factors (with the exception of ankle-brachial index, for which the incidence rate was 10.4 events per 1000 person-years [95% CI, 1.5-73.5]) and combinations of risk-enhancing factors, including participants with 3 or more risk-enhancing factors. Although the individual and composite addition of risk-enhancing factors to the traditional risk factors was associated with improvement in the area under the receiver operating curve, the use of CAC scoring was associated with the greatest improvement in the C statistic (0.633 vs 0.678) for ASCVD events. For incident ASCVD, the net reclassification improvement for CAC was 0.067.Conclusions and relevance: In this cross-sectional study, among participants with CAC scores of 0, the presence of risk-enhancing factors was generally not associated with an overall ASCVD risk that was higher than the recommended treatment threshold for the initiation of statin therapy. The use of CAC scoring was associated with significant improvements in the reclassification and discrimination of incident ASCVD. The results of this study support the utility of CAC scoring as an adjunct to risk-enhancing factor assessment to more accurately classify individuals with an intermediate risk of ASCVD who might benefit from statin therapy