COVID-19 Pandemic Effects on the Activity Levels of Yucatan Mini-Swine (Sus scrofa domesticus).

During the COVID-19 pandemic, unexpected activity patterns emerged among Yucatan mini-swine models for heart failure and atrial fibrillation. As part of our laboratory research, we tracked activity data by FitBark™ collars that the Yucatan mini-swine wore. Previously, staff engaged with the swine daily, such as applying lotion and conducting 6-min treadmill runs. However, pandemic restrictions reduced interaction to 1 or 2 times a week, often for less than 10 min each session. Contrary to expectations, there was a significant increase in the swine's activity levels during these minimal interaction periods. After cleaning, moisturizing, weighing, and FitBark data collection, staff engaged with the swine through feeding and play. Three time frames were analyzed: prepandemic, pandemic, and reentry. Prepandemic and reentry periods involved daily 15-min interactions with 2 staff members per swine to maintain cleanliness and health. During the pandemic, interaction was reduced to 1 or 2 times weekly. The hours between 1000 and 1400 were designated as 'passive activity', representing the swines' isolated behavior, unaffected by staff interaction. The chronic heart failure swine (n = 3) had an average passive activity area under the curve prepandemic value of 47.23 ± 2.52 compared with pandemic 57.09 ± 2.90, pandemic 57.09 ± 2.90 compared with reentry 50.44 ± 1.61, and prepandemic compared with reentry. The atrial fibrillation swine (n = 3) had an average passive activity area under the curve minimal interaction (mimicking pandemic) value of 59.27 ± 6.67 compared with interaction (mimicking prepandemic or reentry) 37.63 ± 1.74. The heightened activity levels during minimal interaction suggest physiologic and psychologic changes in the animals due to reduced socialization. This highlights the importance of enrichment and interaction in research animals and underscores the broader impact of the COVID-19 pandemic on research outcomes. These findings could also shed light on the effects of the pandemic on human behavior.

Surgical treatment for heart failure: cell-based therapy with engineered tissue.

This review will outline cell-based therapy for heart failure focusing on tissue engineering to deliver cells to the damaged heart. We will present an overview of the central approaches focusing on pluripotent stem cell-derived cells, mechanisms of action, autologous vs. allogeneic cell approaches, immunologic modulation, and safety considerations. We will outline the progress that has been made to-date and define the areas that still need to be investigated in order to advance the field.

Human Induced Pluripotent Stem Cell-Derived Cardiomyocyte Patch in Rats With Heart Failure.

BACKGROUND: To treat chronic heart failure (CHF), we developed a robust, easy to handle bioabsorbable tissue-engineered patch embedded with human neonatal fibroblasts and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). This patch was implanted on the epicardial surface of the heart covering the previously infarcted tissue. METHODS: Sprague-Dawley rats (6-8 weeks old) underwent sham surgery (n = 12) or left coronary artery ligation (n = 45). CHF rats were randomized 3 weeks after ligation to CHF control with sham thoracotomy (n = 21), or a fibroblasts/hiPSC-CMs patch (n = 24) was implanted. All sham surgery rats also underwent a sham thoracotomy. At 3 weeks after randomization, hemodynamics, echocardiography, electrophysiologic, and cell survival studies were performed. RESULTS: Patch-treated rats had decreased (P < .05) left ventricular-end diastolic pressure and the time constant of left ventricular relaxation (Tau), increased anterior wall thickness in diastole, and improved echocardiography-derived indices of diastolic function (E/e' [ratio of early peak flow velocity to early peak LV velocity] and e'/a' [ratio of early to late peak left ventricular velocity]). All rats remained in normal sinus rhythm, with no dysrhythmias. Rats treated with the patch showed improved electrical activity. Transplanted hiPSC-CMs were present at 7 days but not detected at 21 days after implantation. The patch increased (P < .05) gene expression of vascular endothelial growth factor, angiopoietin 1, gap junction α-1 protein (connexin 43), ß-myosin heavy 7, and insulin growth factor-1 expression in the infarcted heart. CONCLUSIONS: Epicardial implantation of a fibroblasts/hiPSC-CMs patch electrically enhanced conduction, lowered left ventricular end-diastolic pressure, and improved diastolic function in rats with CHF. These changes were associated with increases in cytokine expression.

Factors in the Selection and Management of Chest Tubes After Pulmonary Lobectomy: Results of a National Survey of Thoracic Surgeons.

BACKGROUND: This study determined patterns of chest tube (CT) selection and management after open lobectomy and minimally invasive lobectomy by thoracic surgeons. METHODS: Surveys were sent electronically to 5,175 thoracic surgeons, and 475 were completed. Responses, blinded so individuals could not be identified, were analyzed and compared according to surgeon characteristics (academic/private practice, years in practice, lobectomy volume, and geographic region). All indicated differences were statistically significant (p < 0.05 by χ(2) tests). RESULTS: CT selection: Most surgeons prefer rigid tubes, and the size most commonly used was 28F. Most place 2 CTs after open lobectomy and 1 CT after minimally invasive lobectomy. Academic surgeons are more likely than private surgeons to use 1 tube after open lobectomy, but both prefer 1 tube after minimally invasive lobectomy. Younger surgeons and high-volume surgeons are more likely to use 1 CT than senior surgeons and low-volume surgeons after both open lobectomy and minimally invasive lobectomy. CT management: Academic and younger surgeons remove the CT sooner after open lobectomy. Younger and high-volume surgeons remove the CT with greater drainage amounts. All groups remove CTs sooner after minimally invasive lobectomy than after open lobectomy. Approximately half of surgeons get a daily chest roentgenogram. Younger and low-volume surgeons are most likely to discharge patients with Heimlich valves, although overall use was in less than 5% (49 of 475) of respondents. Most surgeons believe clinical experience rather than training or the literature determined their CT strategy. CONCLUSIONS: This survey determined the difference in CT management among various groups of surgeons. Clinical experience was the most important factor in determining their CT strategy.