[Prevalence of Echinococcus infections in wild carnivores based on copro - DNA tests in Serthar County of Sichuan Province]

OBJECTIVE

To investigate the prevalence of Echinococcus infections in wild carnivores in Serthar County, Sichuan Province, so as to provide insights into echinococcosis control in local areas.

METHODS

Stool samples were collected from wild carnivores in Serthar County, Sichuan Province in May 2021, and the host sources of stool samples and Echinococcus infections were identified using PCR assays. The prevalence of E. multilocularis, E. granulosus and E. shiquicus infections was estimated in different hosts.

RESULTS

A total of 583 stool samples were collected from wild carnivores, including 147 stool samples from fox, 154 from wolf, 227 from wild dogs and 11 from lynx. The overall prevalence of E. multilocularis, E. granulosus and E. shiquicus infections was 5.68%, 0.19% and 14.20% in canine stool samples, and no E. granulosus infection was detected in fox stool samples, while the prevalence of E. multilocularis and E. shiquicus infections was 0.68% and 47.62% in fox stool samples (χ2 = 88.41, P < 0.001). No E. granulosus or E. shiquicus infection was detected in wolf stool samples, and the prevalence of E. multilocularis infection was 10.39% in wolf stool samples. The prevalence of E. multilocularis, E. granulosus and E. shiquicus infections was 5.73%, 0.44% and 2.20% in canine stool samples (χ2 = 12.13, P < 0.01). In addition, the prevalence of E. multilocularis infections was significantly higher in wolf stool samples than in canine and fox stool samples (χ2 = 13.23, P < 0.01), and the prevalence of E. shiquicus infections was significantly higher in fox stool samples than in canine and wolf stool samples (χ2 = 187.01, P < 0.001). No Echinococcus infection was identified in 11 lynx stool samples.

CONCLUSIONS

The prevalence of Echinococcus infections is high in wild canines in Serthar County, Sichuan Province. Wolf, wild dog and fox all participate in the wild life cycle of E. multilocularis in Serthar County, and wolf and wild dogs may play a more important role.

A suite of engineered mice for interrogating psychedelic drug actions

Psychedelic drugs like lysergic acid diethylamide (LSD) and psilocybin have emerged as potentially transformative therapeutics for many neuropsychiatric diseases, including depression, anxiety, post-traumatic stress disorder, migraine, and cluster headaches. LSD and psilocybin exert their psychedelic effects via activation of the 5-hydroxytryptamine 2A receptor (HTR2A). Here we provide a suite of engineered mice useful for clarifying the role of HTR2A and HTR2A-expressing neurons in psychedelic drug actions. We first generated Htr2a-EGFP-CT-IRES-CreERT2 mice (CT:C-terminus) to independently identify both HTR2A-EGFP-CT receptors and HTR2A-containing cells thereby providing a detailed anatomical map of HTR2A and identifying cell types that express HTR2A. We also generated a humanized Htr2a mouse line and an additional constitutive Htr2A-Cre mouse line. Psychedelics induced a variety of known behavioral changes in our mice validating their utility for behavioral studies. Finally, electrophysiology studies revealed that extracellular 5-HT elicited a HTR2A-mediated robust increase in firing of genetically-identified pyramidal neurons--consistent with a plasma membrane localization and mode of action. These mouse lines represent invaluable tools for elucidating the molecular, cellular, pharmacological, physiological, behavioral, and other actions of psychedelic drugs in vivo.

[Predictive value of the triglyceride-glucose index on atrial fibrillation recurrence after valvular surgery with concurrent Cox-maze Ⅳ ablation]

Objective: To investigate the predictive value of preoperative triglyceride-glucose (TyG) index on atrial fibrillation recurrence after valvular surgery with concurrent Cox-maze Ⅳ ablation. Methods: The data of the patients who underwent valvular surgery with concurrent Cox-maze Ⅳ ablation from June 2017 to May 2022 in the Department of Cardiac Surgery, Beijing Anzhen Hospital were retrospectively collected, and the patients were divided into the recurrence group and non-recurrence group. Baseline clinical data and results of laboratory tests were collected and TyG index was calculated. The univariate and multivariate Cox proportional regression analysis were used to explore the risk factors of atrial fibrillation recurrence after Cox-maze Ⅳ ablation. The value of TyG index in predicting atrial fibrillation recurrence was obtained by plotting receiver operating characteristic (ROC) curve. Results: A total of 424 patients were in the final analysis, including 300 males and 124 females, with an average age of (58.2±13.4) years. The median follow-up time was 32.7 months (17.3-49.6 months). There were 117 and 307 patients in the recurrence and non-recurrence groups, respectively. Compared with the non-recurrence group, the TyG index in the recurrence group was higher (9.21±0.38 vs 8.34±0.72, P=0.011). The multivariate Cox regression analysis showed that TyG index (HR=2.021, 95%CI: 1.374-3.245, P<0.001), C-reactive protein level (HR=1.127, 95%CI: 1.007-1.535, P=0.026) and mitral stenosis (HR=1.038, 95%CI: 1.004-1.483, P<0.001) were risk factors for atrial fibrillation recurrence after Cox-maze Ⅳ ablation. In addition, TyG index was a predictor of atrial fibrillation recurrence according to ROC curve analysis [area under the curve (AUC)=0.847, 95%CI: 0.796-0.871, P<0.001]. Conclusion: The TyG index is an effective indicator to predict the recurrence of atrial fibrillation after valvular surgery with concurrent Cox-maze Ⅳ ablation.

Relationship between in feed drugs, antibiotics and organic enrichment in marine sediments at Canadian Atlantic salmon aquaculture sites

The presence of in-feed anti-sea lice drugs and their relationship with organic enrichment is poorly understood in sediment surrounding salmon farms. Using data from an aquaculture monitoring program (2018-2020), we describe this relationship at ten sites in four Canadian provinces. Three anti-sea lice pesticides (lufenuron, teflubenzuron, emamectin benzoate and metabolite desmethyl emamectin benzoate), and one antibiotic (oxytetracycline) were detected. Concentrations were often below limits of quantification. Values are also lower than those reported in other aquaculture salmon-producing countries. Highest concentrations, along with organic enrichment, were observed ~200 m of cages with lower concentrations detected up to 1.5 km away. Most samples had at least two drugs present: 75.2 % (British Columbia), 91.4 % (Newfoundland), and 54.8 % (New Brunswick/Nova Scotia) highlighting the potential for cumulative effects. Emamectin benzoate and oxytetracycline were detected four and three years respectively after last known treatments, demonstrating the need for research on overall persistence of compounds.

Standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery for sacrocolpopexy

We describe the standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for sacrocolpopexy in women with uterine prolapse. In this video, we demonstrate the key techniques: identifying the right hypogastric nerve (rHN) before opening the pelvic peritoneum; removing the fat and loose connective tissue along the rHN to expose the presacral fascia; incising the presacral fascia to reach the presacral space to expose the middle sacral vasculature and the anterior longitudinal ligament (ALL) of the first sacral vertebra (S1) below the promontory; attaching the mesh to the ALL to avoid vessel injury; and completing the peritonealisation.

[Short-term effect of thoracoscopy-assisted mitral valvuloplasty in patients with mitral valve prolapse]

The data of 56 patients with mitral valve prolapse undergoing thoracoscopy-assisted mitral valvuloplasty in the Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University from May 2019 to December 2020 were retrospectively analyzed. Among them, 31 cases were male and 25 cases were female, with a mean age of (45±14) years. There was no death during perioperative period. No patient was converted to median sternotomy. The duration of cardiopulmonary bypass (CPB), aortic cross-clamp and operation was (207±58) min, (134±59) min, and (374±90) min, respectively. The intraoperative blood loss was (690±268) ml, and 5 (8.9%) patients required blood transfusion. Postoperative mechanical ventilation duration was (19±9) h, and 24-hour pleural fluid drainage volume was (460±247) ml. The length of intensive care unit (ICU) and hospital stay was (25±6) h and (13±4) d, respectively. Therefore, thoracoscopy-assisted mitral valvuloplasty has the advantages of reliable curative effect, less trauma, less complications, fast recovery and satisfactory perioperative outcomes.

Assessing trace-elements as indicators of marine finfish aquaculture across three distinct Canadian coastal regions

Several trace-elements have been identified as indicators of finfish aquaculture organic enrichment. In this study, sediment sampling at finfish farms was completed as part of an Aquaculture Monitoring Program in three distinct Canadian regions. Despite diverse datasets, multivariate analyses show a consistent clustering of known direct (Cu and Zn) and indirect (Cd, Mo and U) tracers of aquaculture activities with sediment organic matter (OM) and/or total dissolved sulfides concentrations. OM content was also a predictor of Cu, Zn, Mo and U concentrations according to decision tree analyses. Distance from cages did not emerge as a strong driver of differences among sampling points; however, a tendency towards negative associations is clear especially for Zn. Enriched stations as determined after geochemical normalization were mostly localized within 150 m of net-pens. Selected trace-elements (in particular Zn) can be useful indicators of aquaculture organic enrichment in different ecosystems and valuable tools for monitoring programs.

[Short-term and long-term outcomes of tricuspid valve replacement in patients with left ventricular dysfunction]

Objective: To examine the short-term and long-term outcomes of tricuspid valve replacement (TVR) in patients with left ventricular dysfunction. Methods: The clinical data of 24 patients with left ventricular dysfunction who received TVR at Department of Cardiovascular Surgery, Beijing Anzhen Hospital, Capital Medical University from November 1993 to August 2018 were consecutively enrolled. There were 14 males and 10 females,aged (41.9±13.2) years old (range: 19 to 66 years old). The preoperative ejection fraction was (42.9±6.4)% (range: 21% to 49%), while less than 35% in 3 patients. The scores of Charlson comorbidity index were as follows: 5 patients for 0, 6 patients for 1, 7 patients for 2, 1 patient for 3 and 5 patients for 4. The European system for cardiac operative risk evaluation (EuroSCORE) Ⅰ was 3.6±2.1 (range: 1 to 9). The EuroSCORE Ⅱ was (4.91±2.40)% (range: 1.58% to 11.60%). The model for end-staged liver disease score was 1.8±1.2 (range: 0.2 to 7.1). The simplified model for end-staged liver disease score was 5.6±2.5 (range: 1.5 to 13.4). Follow-up was conducted by clinic. The long-term survival rate was calculated by Kaplan-Meier survival curve. Results: In-hospital mortality was 16.7% (4/24), including 1 patient for multiple organ failure and 3 patients for low cardiac output syndrome (LCOS). One patient needed continuous renal replacement therapy and 6 patients suffered from LCOS. The follow-up time was 1 to 19 years, with a median of 8 years. During the follow-up period, 4 patients died, including 2 deaths for cardiogenic cause, 1 death for anticoagulant complications, and 1 death for lung cancer. The 1, 5 and 10-year survival rates were 76.2%, 71.4% and 64.9%, respectively. Conclusion: The short-term and long-term clinical outcomes of TVR in patients with left ventricular dysfunction are acceptable, but the mortality and morbidity are still high.

[Impacts of incomplete revascularization following off-pump coronary artery bypass grafting on perioperative outcomes in octogenarians]

Objective: To assess the impacts of incomplete revascularization following off-pump coronary artery bypass grafting (OPCABG) on perioperative outcomes in octogenarians. Methods: A retrospective analysis of 242 octogenarian patients with coronary artery disease (CAD) hospitalized in Beijing Anzhen Hospital from June 2008 to July 2016 was performed. These patients were divided into the complete revascularization group (n=181) and the incomplete revascularization group (n=61) depending on whether they underwent complete revascularization. The impacts of incomplete revascularization following OPCABG on perioperative outcomes were summarized and compared between the two groups. Results: Among the 242 patients over 80 years who received OPCABG, there were 198 males (81.8%). Compared to the complete revascularization group, those in the incomplete revascularization group were older [(83.2±1.5) vs (81.5±1.1) years old, P=0.03], with more carotid stenosis (44.3% vs 25.4%, P=0.01), more involved in the diagonal and circumflex branch of coronary artery (49.2% vs 17.1%, P=0.01; 83.6% vs 70.2%, P=0.03), shorter operative time [(4.1±1.7) h vs (4.7±1.2) h, P=0.03), longer preoperative [(7.1±2.3) d vs (5.2±2.0) d, P=0.01] and total hospitalization time [(16.3±6.8) d vs (12.5±4.2) d, P=0.01], however, the differences of the in-hospital mortality and incidence of other perioperative complications were not statistically significant between the two groups (all P>0.05). Conclusion: Compared with complete revascularization, incomplete revascularization following OPCABG in CAD patients over 80 years old does not increase the perioperative mortality and the incidence of other complications, and it reduces the operative time. However, it increases the time of preoperative and total hospital stay.

[Perioperative outcomes in off-pump coronary artery bypass grafting patients older than 80 years with left ventricular dysfunction or left ventricular normal: a comparative study based on propensity score matching]

Objective: To examine the outcome of off-pump coronary artery bypass (OPCAB) in elderly patients with left ventricular dysfunction. Methods: From June 2008 to July 2016, 252 patients aged over 80 years underwent isolated OPCAB at Department of Cardiovascular Surgery, Beijing Anzhen Hospital, Capital Medical University, these patients' data were collected. The left ventricular dysfunction group (ejection fraction (EF): 35% to 50%) was comprised of 31 patients aged (82.0±2.1) years (range: 80 to 88 years), including 25 males and 6 females. Through matching one-to-one on propensity scores, 31 patients (EF>50%) were included into the left ventricular normal group. Among them, there were 25 males and 6 females, aged (81.9±1.9) years (range: 80 to 89 years). Postoperative mortality and complications between the matched groups were compared using the t test, Wilcoxon rank-sum test, χ(2) test or Fisher exact test. Results: Between the dysfunction group and normal group, the preoperative serum creatinine was 144.6(66.0) μmol/L vs. 94.9(43.2) μmol/L (M(Q(R)), Z=3.177, P=0.033), respectively, while the pre-discharge serum creatinine was 147.0(59.0) μmol/L vs. 92.0(24.0) μmol/L (Z=-2.685, P=0.007), respectively. In dysfunction group, the perioperative intra-aortic balloon counterpulsation (IABP) utilization rate was higher (25.8%(8/31) vs. 3.2%(1/31), P=0.026), the total hospitalization day was longer (17(15) days vs. 14(8)days, Z=2.054, P=0.012), the preoperative hospitalization day was longer too (7(7) days vs. 5(4) days, Z=-2.457, P=0.014). However, there was no significant difference in the incidence of postoperative mortality (9.7%(3/31) vs. 3.2%(1/31), P=0.612) and other prognostic indicators between the two groups. Conclusions: The elderly patients, with light and moderate left ventricular insufficiency, are characterized by the abnormal increase in renal function and the rise of IABP utilization due to hemodynamic disorder in OPCAB perioperative period. Preoperative treatment for cardiac insufficiency may be the cause of prolonged preoperative and total hospital stay. However, there is no significant difference in the postoperative mortality and other complications compared with the patients of normal left ventricular function.

[A comparative analysis of quality of life between surgical and interventional treatment in patients with complex coronary heart disease]

Objective: To compare the improvement of quality of life in the patients with left main coronary artery disease and multi-vessel disease between off-pump coronary artery bypass grafting (OPCABG) and percutaneous coronary intervention (PCI) within one year after revascularization. Methods: This study was a prospective study. Between January and July 2018, 840 patients with complex coronary heart disease accepted revascularization therapy, 420 of whom underwent OPCABG and 420 for PCI, with a mean age of 61 years and a male rate of 74% (622/840). European Quality of Life-5 Dimensions (EQ-5D) and Seattle Angina Questionnaire (SAQ) were employed to assess the quality of life and health status of patients. Inverse probability weighting (IPW) was used to adjust treatment selection bias. Results: All-cause mortality (3.6% vs 1.3%, P=0.045), major adverse cardiac and cerebrovascular events (MACCE) (11.3% vs 4.1%, P<0.001) and target lesion revascularization (8.3% vs 1.2%, P<0.001) were higher in PCI group than those in OPCABG group. EQ-5D scores in PCI group were significantly higher than those in OPCABG group at 1 month after operation (P<0.001), but there was no significant difference between the two groups at 12 months after operation (P=0.210). In SAQ scale, the frequency score of angina pectoris in OPCABG group was higher than that in PCI group in 1 month, 6 months and 12 months after operation (all P<0.05). The physical activity limitation score in PCI group was significantly higher than that in OPCABG group at one month after operation (P<0.01). There was no significant difference between OPCABG group and PCI group in terms of stable state of angina pectoris, satisfaction of treatment and the knowledge of disease. Conclusions: In the short term, the quality of life of patients with left main coronary artery disease and multi-vessel disease treated with OPCABG is better than PCI. However, the improvement of quality of life in the medium and long term still needs to be identified in future follow-up study.

microRNA-146a-5p association with the cardiometabolic disease risk factor TMAO

Trimethylamine-N-oxide (TMAO), a microbial choline metabolism byproduct that is processed in the liver and excreted into circulation, is associated with increased atherosclerotic lesion formation and cardiovascular disease risk. Genetic regulators of TMAO levels are largely unknown. In the present study, we used 288 mice from a genetically heterogeneous mouse population [Diversity Outbred (DO)] to determine hepatic microRNA associations with TMAO in the context of an atherogenic diet. We also validated findings in two additional animal models of atherosclerosis: liver-specific insulin receptor knockout mice fed a chow diet (LIRKO) and African green monkeys fed high-fat/high-cholesterol diet. Small RNA-sequencing analysis in DO mice, LIRKO mice, and African green monkeys identified only one hepatic microRNA (miR-146a-5p) that is aberrantly expressed across all three models. Moreover, miR-146a-5p levels are associated with circulating TMAO after atherogenic diet in each of these models. We also performed high-resolution genetic mapping and identified a novel quantitative trait locus on Chromosome 12 for TMAO levels. This interval includes two genes, Numb and Dlst, which are inversely correlated with both miR-146a and TMAO and are predicted targets of miR-146a. Both of these genes have been validated as direct targets of miR-146a, though in other cellular contexts. This is the first report to our knowledge of a link between miR-146 and TMAO. Our findings suggest that miR-146-5p, as well as one or more genes at the Chromosome 12 QTL (possibly Numb or Dlst), is strongly linked to TMAO levels and likely involved in the control of atherosclerosis.

Modified Model of Whole Ovary Transplantation in Rats

OBJECTIVE

A rat model of right whole ovary transplantation is difficult to establish because of an unfit location or absence of the right ovarian artery. The purpose of this study is to develop a rat model of left whole ovary transplantation.

METHODS

Two methods of whole ovary transplantation were performed. In Group A (n = 40), the rats underwent right whole ovary grafting via conventional orthotopic allotransplant, with donor abdominal aorta and inferior vena cava end-to-side anastomoses to the recipient abdominal aorta and inferior vena cava. In Group B (n = 40), the rats underwent left whole ovary graft via orthotopic allotransplant, with donor abdominal aorta and left renal vein end-to-side anastomoses to the recipient abdominal aorta and inferior vena cava. Bilateral native ovariectomy in the recipient was performed immediately in both groups. The operative times, recipient survival rates, and transplanted ovarian function were measured.

RESULTS

There was no significant difference in the success rates of transplant between the 2 groups, with 92.5% and 90% success, respectively. All the living recipients recovered ovarian function. However, the operative time for the donor, the vein anastomosis time, and the cold ischemia time decreased significantly in Group B (P < .05).

CONCLUSION

The modified method of left whole ovary transplantation is reliable and easy to perform, which could significantly shorten the times of graft harvest and cold ischemia. The method is a good supplement and improvement of the conventional model of rat whole ovary transplantation.

CC002/Unc females are mouse models of exercise-induced paradoxical fat response

Exercise results in beneficial health outcomes and protects against a variety of chronic diseases. However, U.S. exercise guidelines recommend identical exercise programs for everyone, despite individual variation in responses to these programs, including paradoxical fat gain. Experimental models of exercise-induced paradoxical outcomes may enable the dissection of underlying physiological mechanisms as well as the evaluation of potential interventions. Whereas several studies have identified individual mice exhibiting paradoxical fat gain following exercise, no systematic effort has been conducted to identify and characterize models of paradoxical response. Strains from the Collaborative Cross (CC) genetic reference population were used due to its high levels of genetic variation, its reproducible nature, and the observation that the CC is a rich source of novel disease models, to assess the impact genetic background has on exercise responses. We identified the strain CC002/Unc as an exercise-induced paradoxical fat response model in a controlled voluntary exercise study across multiple ages in female mice. We also found sex and genetic differences were consistent with this pattern in a study of forced exercise programs. These results provide a novel model for studies to determine the mechanisms behind paradoxical metabolic responses to exercise, and enable development of more rational personalized exercise recommendations based on factors such as age, sex, and genetic background.

[Short-term clinical safety and efficacy of No-touch great saphenous vein harvesting technique for off-pump coronary artery bypass grafting]

Objective: To evaluated early clinical outcomes of saphenous vein grafts harvested with a No-touch technique in off-pump coronary artery bypass graft (OPCABG) surgery. Methods: A total of 124 patients with three-vessel disease undergoing OPCABG by No-touch technique between June and November 2017 in Beijing An Zhen Hospital were respectively reviewed. Results: The average age of patients was (60.7±10.3) years, and 80 cases (64.5%) were male, with the average body mass index (BMI)of (25.4±2.5) kg/m(2,) the mean preoperative left ventricular ejection fraction (LVEF) of (58.0±7.0%). The operative time was (4.0±0.4) hours, and 16 cases (12.9%) were harvested for whole vein grafts. The number of vein grafts and venous anastomoses was 144 and 284, respectively. There were 16 cases of single bridge NTSVG-LAD, 4 cases of single bridge NTSVG-D, 99 cases of sequential bridge NTSVG-OM-PDA, 5 cases of sequential bridge NTSVG-OM-PLV, 4 cases of sequential bridge NTSVG-OM-RCA, 16 cases of sequential bridge NTSVG-D-OM-PDA. The mean flow volume of No-touch vein grafts was (51.9±2.4) ml/min. There was no death case in hospital. Postoperative re-exploration for hemorrhage of anastomosis happened in 1 case (0.8%), which was caused by pericardial tamponade due to insufficiency of hemostasis in internal mammary bed. There were 1 case of bad wound healing of lower extremity incision (0.8%). A total of 124 cases were followed up after operation, and the follow-up rate was 100%. There was one all-cause death (0.8%) 27 days after the operation. Conclusion: The short-term clinical observation of the application of No-touch great saphenous vein harvesting technique for OPCABG is safe and effective.

Developmental constraint through negative pleiotropy in the zygomatic arch

BACKGROUND

Previous analysis suggested that the relative contribution of individual bones to regional skull lengths differ between inbred mouse strains. If the negative correlation of adjacent bone lengths is associated with genetic variation in a heterogeneous population, it would be an example of negative pleiotropy, which occurs when a genetic factor leads to opposite effects in two phenotypes. Confirming negative pleiotropy and determining its basis may reveal important information about the maintenance of overall skull integration and developmental constraint on skull morphology.

RESULTS

We identified negative correlations between the lengths of the frontal and parietal bones in the midline cranial vault as well as the zygomatic bone and zygomatic process of the maxilla, which contribute to the zygomatic arch. Through gene association mapping of a large heterogeneous population of Diversity Outbred (DO) mice, we identified a quantitative trait locus on chromosome 17 driving the antagonistic contribution of these two zygomatic arch bones to total zygomatic arch length. Candidate genes in this region were identified and real-time PCR of the maxillary processes of DO founder strain embryos indicated differences in the RNA expression levels for two of the candidate genes, Camkmt and Six2.

CONCLUSIONS

A genomic region underlying negative pleiotropy of two zygomatic arch bones was identified, which provides a mechanism for antagonism in component bone lengths while constraining overall zygomatic arch length. This type of mechanism may have led to variation in the contribution of individual bones to the zygomatic arch noted across mammals. Given that similar genetic and developmental mechanisms may underlie negative correlations in other parts of the skull, these results provide an important step toward understanding the developmental basis of evolutionary variation and constraint in skull morphology.

Quantitative trait mapping in Diversity Outbred mice identifies two genomic regions associated with heart size

Heart size is an important factor in cardiac health and disease. In particular, increased heart weight is predictive of adverse cardiovascular outcomes in multiple large community-based studies. We use two cohorts of Diversity Outbred (DO) mice to investigate the role of genetics, sex, age, and diet on heart size. DO mice (n = 289) of both sexes from generation 10 were fed a standard chow diet, and analyzed at 12-15 weeks of age. Another cohort of female DO mice (n = 258) from generation 11 were fed either a high-fat, cholesterol-containing (HFC) diet or a low-fat, high-protein diet, and analyzed at 24-25 weeks. We did not observe an effect of diet on body or heart weight in generation 11 mice, although we previously reported an effect on other cardiovascular risk factors, including cholesterol, triglycerides, and insulin. We do observe a significant genetic effect on heart weight in this population. We identified two quantitative trait loci for heart weight, one (Hwtf1) at a genome-wide significance level of p ≤ 0.05 on MMU15 and one (Hwtf2) at a genome-wide suggestive level of p ≤ 0.1 on MMU10, that together explain 13.3% of the phenotypic variance. Hwtf1 contained collagen type XXII alpha 1 chain (Col22a1), and the NZO/HlLtJ and WSB/EiJ haplotypes were associated with larger hearts. This is consistent with heart tissue Col22a1 expression in DO founders and SNP patterns within Hwtf1 for Col22a1. Col22a1 has been previously associated with cardiac fibrosis in mice, suggesting that Col22a1 may be involved in pathological cardiac hypertrophy.

Aerobic exercise prevents rarefaction of pial collaterals and increased stroke severity that occur with aging

Variation in extent of the brain's collateral circulation is an important determinant of variation in the severity of stroke and efficacy of revascularization therapies. However, the number and diameter of pial collateral "arterioles" decrease with aging in associated with reduced eNOS and increased oxidative stress. We tested whether exercise reduces this aging-induced rarefaction. Twelve-month-old mice were randomized to sedentary or voluntary wheel-running. At 26 months' age, permanent MCA occlusion was followed 72 h later by determination of infarct volume and vascular casting after maximal dilation. The decline in collateral number and diameter and 2.4-fold increase in infarct volume evident in 26-versus 3-month-old sedentary mice were prevented by exercise-training. In contrast, number and diameter of the posterior communicating collateral "arteries" were unaffected by aging or exercise. Interestingly, diameter of the primary intracranial arteries increased with aging. Mechanistically, genetic overexpression of eNOS inhibited age-induced collateral rarefaction, and exercise increased eNOS and SOD2 and decreased the inflammatory marker NFkB assessed in hindlimb arteries. In conclusion, exercise prevented age-induced rarefaction of pial collaterals and reduced infarct volume. Aging also promoted outward remodeling of intracranial arteries. These effects were associated with increased eNOS and reduced markers of inflammation and aging in the vascular wall.

Systems genetics identifies a co-regulated module of liver microRNAs associated with plasma LDL cholesterol in murine diet-induced dyslipidemia

Chronically altered levels of circulating lipids, termed dyslipidemia, is a significant risk factor for a number of metabolic and cardiovascular morbidities. MicroRNAs (miRNAs) have emerged as important regulators of lipid balance, have been implicated in dyslipidemia, and have been proposed as candidate therapeutic targets in lipid-related disorders including atherosclerosis. A major limitation of most murine studies of miRNAs in lipid metabolic disorders is that they have been performed in just one (or very few) inbred strains, such as C57BL/6. Moreover, although individual miRNAs have been associated with lipid phenotypes, it is well understood that miRNAs likely work together in functional modules. To address these limitations, we implemented a systems genetics strategy using the Diversity Outbred (DO) mouse population. Specifically, we performed gene and miRNA expression profiling in the livers from ~300 genetically distinct DO mice after 18 wk on either a high-fat/high-cholesterol diet or a high-protein diet. Large-scale correlative analysis of these data with a wide range of cardio-metabolic end points revealed a co-regulated module of miRNAs significantly associated with circulating low-density lipoprotein cholesterol (LDL-C) levels. The hubs of this module were identified as miR-199a, miR-181b, miR-27a, miR-21_-_1, and miR-24. In sum, we demonstrate that a high-fat/high-cholesterol diet robustly rewires the miRNA regulatory network, and we identify a small group of co-regulated miRNAs that may exert coordinated effects to control circulating LDL-C.

[Short-term clinical outcomes and risk factors associated with in-hospital mortality in patients undergoing off-pump coronary artery bypass grafting]

Objective: To explore short-term clinical outcomes and risk factors associated with in-hospital mortality in patients undergoing off-pump coronary artery bypass grafting (OPCABG) and establish a prediction model for in-hospital mortality. Methods: The clinical data of patients undergoing OPCABG in Beijing Anzhen Hospital between January 2014 and January 2016 was retrospectively studied. Univariate analysis and logistic regression were applied to determine the potential risk factors, and then a prediction model for mortality was confirmed. The calibration and discrimination of the prediction model was finally tested. Results: A total of 2 546 patients who underwent OPCABG were recruited. In-hospital mortality of OPCABG was 0.7% (17 cases). Seven variables: female, age, left main disease >50%, low left ventricular ejection fraction (LVEF), acute myocardial infarction before surgery, operative status (selective or emergent), moderate concomitant mitral valve regurgitation were independently correlated with OPCABG mortality (all P<0.05). The result of Hosmer-Lemeshow test was χ(2)=5.912, P=0.676. The area under receiver-operating characteristic curve (ROC) was 0.881. Conclusions: OPCABG is safe and effective for myocardial revascularization in a short term. The following risk factors are associated with an increased operative mortality of OPCABG: male, age, left main disease >50%, low LVEF, acute myocardial infarction before surgery, operative status (selective or emergent), moderate concomitant mitral valve regurgitation. The prediction model established by above-mentioned potential risk factors was proven to perform well by statistical tests.

Prevention of tumorigenesis in mice by exercise is dependent on strain background and timing relative to carcinogen exposure

Among cancer diagnoses, colorectal cancer (CRC) is prevalent, with a lifetime risk of developing CRC being approximately 5%. Population variation surrounding the mean risk of developing CRCs has been associated with both inter-individual differences in genomic architecture and environmental exposures. Decreased risk of CRC has been associated with physical activity, but protective responses are variable. Here, we utilized a series of experiments to examine the effects of genetic background (strain), voluntary exercise (wheel running), and their interaction on azoxymethane (AOM)-induced intestinal tumor number and size in mice. Additionally, we investigated how the timing of exercise relative to AOM exposure, and amount of exercise, affected tumor number and size. Our results indicated that voluntary exercise significantly reduced tumor number in a strain dependent manner. Additionally, among strains where exercise reduced tumor number (A/J, CC0001/Unc) the timing of voluntary exercise relative to AOM exposure was crucial. Voluntary exercise prior to or during AOM treatment resulted in a significant reduction in tumor number, but exercise following AOM exposure had no effect. The results indicate that voluntary exercise should be used as a preventative measure to reduce risk for environmentally induced CRC with the realization that the extent of protection may depend on genetic background.

Long-term exercise in mice has sex-dependent benefits on body composition and metabolism during aging

Aging is associated with declining exercise and unhealthy changes in body composition. Exercise ameliorates certain adverse age‐related physiological changes and protects against many chronic diseases. Despite these benefits, willingness to exercise and physiological responses to exercise vary widely, and long‐term exercise and its benefits are difficult and costly to measure in humans. Furthermore, physiological effects of aging in humans are confounded with changes in lifestyle and environment. We used C57BL/6J mice to examine long‐term patterns of exercise during aging and its physiological effects in a well‐controlled environment. One‐year‐old male (n = 30) and female (n = 30) mice were divided into equal size cohorts and aged for an additional year. One cohort was given access to voluntary running wheels while another was denied exercise other than home cage movement. Body mass, composition, and metabolic traits were measured before, throughout, and after 1 year of treatment. Long‐term exercise significantly prevented gains in body mass and body fat, while preventing loss of lean mass. We observed sex‐dependent differences in body mass and composition trajectories during aging. Wheel running (distance, speed, duration) was greater in females than males and declined with age. We conclude that long‐term exercise may serve as a preventive measure against age‐related weight gain and body composition changes, and that mouse inbred strains can be used to characterize effects of long‐term exercise and factors (e.g. sex, age) modulating these effects. These findings will facilitate studies on relationships between exercise and health in aging populations, including genetic predisposition and genotype‐by‐environment interactions.

Molecular Pathogenesis of Pancreatic Cancer

Pancreatic cancers arise predominantly from ductal epithelial cells of the exocrine pancreas and are of the ductal adenocarcinoma histological subtype (PDAC). PDAC is an aggressive disease associated with a poor clinical prognosis, weakly effective therapeutic options, and a lack of early detection methods. Furthermore, the genetic and phenotypic heterogeneity of PDAC complicates efforts to identify universally efficacious therapies. PDACs commonly harbor activating mutations in the KRAS oncogene, which is a potent driver of tumor initiation and maintenance. Inactivating mutations in tumor suppressor genes such as CDKN2A/p16, TP53, and SMAD4 cooperate with KRAS mutations to cause aggressive PDAC tumor growth. PDAC can be classified into 3-4 molecular subtypes by global gene expression profiling. These subtypes can be distinguished by distinct molecular and phenotypic characteristics. This chapter will provide an overview of the current knowledge of PDAC pathogenesis at the genetic and molecular level as well as novel therapeutic opportunities to treat this highly aggressive disease.