Search Results (16)

Background and Objectives: Effective myocardial protection is essential for successful cardiac surgery outcomes, especially in complex and prolonged procedures. To this end, Del Nido (DN) and histidine-tryptophan-ketoglutarate (HTK) cardioplegia solutions are widely used; however, their comparative efficacy in adult surgeries with prolonged aortic cross-clamp (ACC) times remains unclear. This study aimed to compare the efficacy and safety of DN and HTK for myocardial protection during prolonged ACC times in adult cardiac surgery and to define clinically relevant thresholds. Materials and Methods: This retrospective study included a total of 320 adult patients who underwent cardiac surgery under cardiopulmonary bypass (CPB) with an aortic cross-clamp time ≥ 90 min. Data were collected from the medical records of elective adult cardiac surgery cases performed at a single center between 2019 and 2025. Patients were categorized into two groups based on the type of cardioplegia received: Del Nido (n = 160) and HTK (n = 160). The groups were compared using 1:1 propensity score matching. Clinical and biochemical outcomes—including troponin I (TnI), CK-MB, lactate levels, incidence of low cardiac output syndrome (LCOS), and need for mechanical circulatory support—were analyzed between the two cardioplegia groups. Subgroup analyses were performed according to ACC duration (90–120, 120–150, 150–180 and >180 min). The predictive threshold of ACC duration for each complication was determined by ROC analysis, followed by the analysis of independent predictors of each endpoint by multivariate logistic regression. Results: Intraoperative cardioplegia volume and transfusion requirements were lower in the DN group (p < 0.05). HTK was associated with lower TnI levels and less intra-aortic balloon pump (IABP) requirement at ACC times exceeding 180 min. Markers of myocardial injury were lower in patients with an ACC duration of 120–150 min in favor of HTK. The propensity for ventricular fibrillation after ACC was significantly lower in the DN group. Significantly lower postoperative sodium levels were observed in the HTK group. Prolonged ACC duration was an independent risk factor for LCOS (odds ratio [OR]: 1.023, p < 0.001), VIS > 15 (OR, 1.015; p < 0.001), IABP requirement (OR: 1.020, p = 0.002), and early mortality (OR: 1.016, p = 0.048). Postoperative ejection fraction (EF), troponin I, and CK-MB levels were associated with the development of LCOS and a VIS > 15. Furthermore, according to ROC analysis, HTK cardioplegia was able to tolerate ACC for up to a longer duration in terms of certain complications, suggesting a higher physiological tolerance to ischemia. Conclusions: ACC duration is a strong predictor of major adverse outcomes in adult cardiac surgeries. Although DN cardioplegia is effective and economically advantageous for shorter procedures, HTK may provide superior myocardial protection in operations with long ACC duration. This study supports the need to individualize cardioplegia choice according to ACC duration. Further prospective studies are needed to establish standard dosing protocols and to optimize cardioplegia selection according to surgical duration and complexity. Full article

Background: Disadvantaged children often enter kindergarten with delays in fundamental motor skill (FMS) competence, which is critical for future physical activity engagement. The Summer Success—Successful Kinesthetic Instruction for Preschoolers (SS-SKIP) program was designed to address these developmental gaps, with a short, intensive intervention. This pilot study evaluated the impact of a 4-week SS-SKIP program on FMS, perceived motor competence (PMC), and executive function (EF). Methods: Twenty-one preschool children (mean age = 62.62 ± 4.61 months) from disadvantaged communities participated in an intensive, month-long (240 min) program. FMS were assessed using the Test of Gross Motor Development-2 (TGMD-2), PMC was evaluated using the Pictorial Scale for Perceived Competence, and EF was measured via the Head–Toes–Knees–Shoulders (HTKS), Go/No-Go, and Sorting cards tests. Standing long jump was measured in meters. A pretest–post-test design assessed program impact using 2 Gender X 2 Session MANOVAs/ANOVAs on dependent variables. Results: Analysis of differences in baseline measures of FMS competence and EF by Gender and Session revealed no significant main effects of Gender, Session, or their interaction across measures (all p > 0.05). Repeated measures ANOVAs by Gender revealed a significant main effect for Time for locomotor standard scores (p < 0.001), object control standard scores (p < 0.001), and HTKS scores (p < 0.001), indicating improvement from pretest to post-test. By contrast, jump distance, PMC, Go/No-Go and Card Sorting scores were non-significant (p > 0.05). Conclusions: A short, intense SS-SKIP FMS intervention significantly enhanced FMS and improved HTKS performance. This pilot study was limited by the lack of a control group and small N. These findings underscore the potential of short, targeted interventions in addressing early motor delays in disadvantaged preschoolers, warranting further investigation into their long-term impacts. Full article

Brain injury and cerebral inflammation are frequent complications following cardiopulmonary bypass (CPB) resulting in neurocognitive dysfunction, encephalopathy, or stroke. We compared cerebral inflammation induced by del Nido and histidine-tryptophan-α-ketoglutarate (HTK) cardioplegia in a porcine model. Pigs underwent 90 min cardiac arrest using HTK (n = 9) or Jonosteril^®-based del Nido cardioplegia (n = 9), followed by a 120 min reperfusion. Brain biopsies were collected and analyzed for the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and cytokines. HTK induced a decrease in blood sodium, chloride, and calcium concentration (cross-clamp aorta: p_sodium < 0.01, p_chloride < 0.01, p_calcium < 0.01; 90 min ischemia: p_sodium < 0.01, p_chloride < 0.01, p_calcium = 0.03) compared to the more stable physiological electrolyte concentrations during del Nido cardioplegia. Hyponatremia and hypochloremia persisted after a 120 min reperfusion in the HTK group (p_sodium < 0.01, p_chloride = 0.04). Compared to del Nido, a higher mRNA expression of the proinflammatory cytokine IL-1β was detected in the frontal cortex (HTK: ∆Ct 6.5 ± 1.7; del Nido: ∆Ct 8.8 ± 1.5, p = 0.01) and the brain stem (HTK: ∆Ct 5.7 ± 1.5; del Nido: ∆Ct 7.5 ± 1.6, p = 0.02) of the HTK group. In conclusion, we showed comparability of HTK and del Nido for cerebral inflammation except for IL-1β expression. Based on our study results, we conclude that del Nido cardioplegia is a suitable and safe alternative to the conventional HTK solution. Full article

Background: Machine perfusion (MP) offers extended preservation of vascularized complex allografts (VCA), but the diagnostic value of histology using hematoxylin and eosin (H&E) in detecting ischemia–reperfusion injury (IRI) in muscle cells remains unclear. This study aims to document the application of the Histology Injury Severity Score (HISS) and to assess whether additional staining for nicotinamide adenine dinucleotide (NADH) and membrane attack complex (MAC) improves IRI detection in a porcine limb replantation model. Methods: The forelimbs of 16 Dutch Landrace pigs were amputated and preserved for 24 h using hypothermic MP (n = 8) with Histidine-Tryptophan-Ketoglutarate (HTK) or for 4 h with SCS (n = 8) before heterotopic replantation and 7 days of follow-up. Muscle damage was assessed via biochemical markers and light microscopy using H&E, NADH, and MAC at baseline, post-intervention, and post-operative day (POD) 1, 3, and 7 timepoints, using the HISS and a self-developed NADH and MAC score. Results: H&E effectively identified damaged muscle fibers and contributed to IRI assessment in porcine limbs (p < 0.05). The highest HISS was measured on POD 3 between MP (4.9) and SCS (3.5) (p = 0.029). NADH scores of both preservation groups varied over the 7-day follow-up and were statistically insignificant compared with baseline measurements (p > 0.05). MAC revealed no to minimal necrotic tissue across the different timepoints. Conclusions: This study documents the application of the HISS with H&E to detect IRI in muscle fibers. NADH and MAC showed no significant added diagnostic utility. The 24 h MP showed similar muscle alterations using the HISS compared to that of the 4 h SCS after a 7-day follow up. Full article

Protection of the coronary arteries during donor heart maintenance is pivotal to improve results and prevent the development of coronary allograft vasculopathy. The effect of hypothermic, oxygenated perfusion (HOP) with the traditional HTK and the novel HTK-N solution on the coronary microvasculature of donation-after-circulatory-death (DCD) hearts is known. However, the effect on the coronary macrovasculature is unknown. Thus, we maintained porcine DCD hearts by HOP with HTK or HTK-N for 4 h, followed by transplantation-equivalent reperfusion with blood for 2 h. Then, we removed the left anterior descending coronary artery (LAD) and compared the endothelial-dependent and -independent vasomotor function of both groups using bradykinin and sodium-nitroprusside (SNP). We also determined the transcriptome of LAD samples using microarrays. The endothelial-dependent relaxation was significantly better after HOP with HTK-N. The endothelial-independent relaxation was comparable between both groups. In total, 257 genes were expressed higher, and 668 genes were expressed lower in the HTK-N group. Upregulated genes/pathways were involved in endothelial and vascular smooth muscle cell preservation and heart development. Downregulated genes were related to ischemia/reperfusion injury, oxidative stress, mitochondrion organization, and immune reaction. The novel HTK-N solution preserves the endothelial function of DCD heart coronary arteries more effectively than traditional HTK. Full article

Donation after circulatory death (DCD) hearts are predominantly maintained by normothermic blood perfusion (NBP). Nevertheless, it was shown that hypothermic crystalloid perfusion (HCP) is superior to blood perfusion to recondition left ventricular (LV) contractility. However, transcriptomic changes in the myocardium and coronary artery in DCD hearts after HCP and NBP have not been investigated yet. In a pig model, DCD hearts were harvested and maintained for 4 h by NBP (DCD-BP group, N = 8) or HCP with oxygenated histidine–tryptophane–ketoglutarate (HTK) solution (DCD-HTK, N = 8) followed by reperfusion with fresh blood for 2 h. In the DCD group (N = 8), hearts underwent reperfusion immediately after procurement. In the control group (N = 7), no circulatory death was induced. We performed transcriptomics from LV myocardial and left anterior descending (LAD) samples using microarrays (25,470 genes). We applied the Boruta algorithm for variable selection to identify relevant genes. In the DCD-BP group, compared to DCD, six genes were regulated in the myocardium and 1915 genes were regulated in the LAD. In the DCD-HTK group, 259 genes were downregulated in the myocardium and 27 in the LAD; and 52 genes were upregulated in the myocardium and 765 in the LAD, compared to the DCD group. We identified seven genes of relevance for group identification: ITPRIP, G3BP1, ARRDC3, XPO6, NOP2, SPTSSA, and IL-6. NBP resulted in the upregulation of genes involved in mitochondrial calcium accumulation and ROS production, the reduction in microvascular endothelial sprouting, and inflammation. HCP resulted in the downregulation of genes involved in NF-κB-, STAT3-, and SASP-activation and inflammation. Full article

The impact of the machine perfusion of donation after circulatory death (DCD) hearts with the novel Custodiol-N solution on diastolic and coronary microvascular dysfunction is unknown. Porcine DCD-hearts were maintained four hours by perfusion with normothermic blood (DCD-B), hypothermic Custodiol (DCD-C), or Custodiol-N (DCD-CN), followed by one hour of reperfusion with fresh blood, including microvascular and contractile evaluation. In another group (DCD group), one hour of reperfusion, including microvascular and contractile evaluation, was performed without a previous maintenance period (all groups N = 5). We measured diastolic function with a balloon catheter and microvascular perfusion by Laser-Doppler-Technology, resulting in Laser-Doppler-Perfusion (LDP). We performed immunohistochemical staining and gene expression analysis. The developed pressure was improved in DCD-C and DCD-CN. The diastolic pressure decrement (DCD-C: −1093 ± 97 mmHg/s; DCD-CN: −1703 ± 329 mmHg/s; DCD-B: −690 ± 97 mmHg/s; p < 0.05) and relative LDP (DCD-CN: 1.42 ± 0.12; DCD-C: 1.11 ± 0.13; DCD-B: 1.22 ± 0.27) were improved only in DCD-CN. In DCD-CN, the expression of eNOS increased, and ICAM and VCAM decreased. Only in DCD-B compared to DCD, the pathways involved in complement and coagulation cascades, focal adhesion, fluid shear stress, and the IL-6 and IL-17 pathways were upregulated. In conclusion, machine perfusion with Custodiol-N improves diastolic and microvascular function and preserves the microvascular endothelium of porcine DCD-hearts. Full article

Mitochondria are targets of cold ischemia-reperfusion (IR), the major cause of cell damage during static cold preservation of liver allografts. The bioactivity of methane (CH₄) has recently been recognized in various hypoxic and IR conditions as having influence on many aspects of mitochondrial biology. We therefore hypothesized that cold storage of liver grafts in CH₄-enriched preservation solution can provide an increased defence against organ dysfunction in a preclinical rat model of liver transplantation. Livers were preserved for 24 h in cold histidine–tryptophan–ketoglutarate (HTK) or CH₄-enriched HTK solution (HTK-CH₄) (n = 24 each); then, viability parameters were monitored for 60 min during normothermic isolated reperfusion and perfusate and liver tissue were collected. The oxidative phosphorylation capacity and extramitochondrial Ca²⁺ movement were measured by high resolution respirometry. Oxygen and glucose consumption increased significantly while hepatocellular damage was decreased in the HTK-CH₄ grafts compared to the HTK group. Mitochondrial oxidative phosphorylation capacity was more preserved (128.8 ± 31.5 pmol/s/mL vs 201.3 ± 54.8 pmol/s/mL) and a significantly higher Ca²⁺ flux was detected in HTK-CH₄ storage (2.9 ± 0.1 mV/s) compared to HTK (2.3 ± 0.09 mV/s). These results demonstrate the direct effect of CH₄ on hepatic mitochondrial function and extramitochondrial Ca²⁺ fluxes, which may have contributed to improved graft functions and a preserved histomorphology after cold IR. Full article

Tumor heterogeneity limits the efficacy and reliability of monospecific radiopharmaceuticals in prostate cancer diagnosis and therapy. To overcome this limitation and improve lesion detection sensitivity, we developed and evaluated three bispecific radiotracers that can target both prostate-specific membrane antigen (PSMA) and fibroblast activation protein (FAP), which are the two key proteins overexpressed in prostate cancer. Three FAP-targeting ligands with various linker lengths were synthesized through multistep organic synthesis, and then connected to the PSMA-targeting motif. IC₅₀(PSMA) and IC₅₀(FAP) values of Ga-complexed bispecific ligands, Ga-AV01017, Ga-AV01030, and Ga-AV01038 were 25.2–71.6 and 1.25–2.74 nM, respectively. The uptake values in PSMA-expressing LNCaP tumor xenografts were 4.38 ± 0.55, 5.17 ± 0.51, and 4.25 ± 0.86 %ID/g for [⁶⁸Ga]Ga-AV01017, [⁶⁸Ga]Ga-AV01030, and [⁶⁸Ga]Ga-AV01038, respectively, which were lower than the monospecific PSMA-targeting tracer [⁶⁸Ga]Ga-HTK03041 (23.1 ± 6.11 %ID/g). The uptake values in FAP-expressing HEK293T:hFAP tumor xenografts were 2.99 ± 0.37, 3.69 ± 0.81, 3.64 ± 0.83 %ID/g for [⁶⁸Ga]Ga-AV01017, [⁶⁸Ga]Ga-AV01030, and [⁶⁸Ga]Ga-AV01038, respectively, which were also lower than the monospecific FAP-targeting tracer, [⁶⁸Ga]Ga-FAPI-04 (12.5 ± 2.00 %ID/g). We observed that the bispecific tracers had prolonged blood retention, in which tracers with a longer linker tend to have a higher blood uptake and lower tumor uptake. Further investigations are needed to optimize the linker selection to generate promising bispecific PSMA/FAP-targeting tracers for prostate cancer imaging. Full article

Uterus transplantation (UTx) is the only treatment method for women with absolute uterine infertility. Currently, the number of grafts retrieved from deceased donors is increasing; hence, prolonged cold ischemia time is inevitable. Thus, this study was designed to assess the effect of the novel relaxin (RLN)- or erythropoietin (EPO)-supplemented Custodiol-N (HTK-N) solutions in an experimental uterus static cold storage (SCS) model. A total of 15 Sprague Dawley rats were used. Uterus horns were randomly assigned into three groups (n = 10/group). SCS was performed by keeping samples at 4 °C in HTK-N solution without or with different additives: 10 IU/mL EPO or 20 nM RLN. Tissue samples were taken after 8 and 24 h of preservation. Uterine tissue histology, and biochemical and immunohistochemical markers were analyzed. No significant differences in SCS-induced tissue damage were observed between groups after 8 h of preservation. Uterine tissue histology, MDA, SOD levels and the TUNEL-positive cell number showed severe damage in HTK-N without additives after 24 h of preservation. This damage was significantly attenuated by adding RLN to the preservation solution. EPO showed no favorable effect. Our study shows that RLN as an additive to an HTK-N solution can serve as an effective uterine tissue preservative in the uterus SCS setting. Full article

Kochujang shows anti-obesity effects in cell and animal models. Kochujang is traditionally prepared via slow fermentation or commercially using Aspergillus oryzae. We analyze the anti-obesity effects of two types of Kochujang in overweight and obese adults. The analyses included the following groups: traditional Kochujang containing either a high-dose (HTK; n = 19), or a low-dose of beneficial microbes (LTK; n = 18), and commercial Kochujang (CK; n = 17). Waist circumference decreased significantly in the HTK and CK groups. Total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride levels decreased in the HTK and LTK groups. Visceral fat is significantly reduced in the HTK group. The population of beneficial microorganisms in stool samples increased in all groups. Consumption of Kochujang reduces visceral fat content and improves the lipid profile, which can be enhanced by enrichment with beneficial microbes. These results suggest that Kochujang has the potential for application in obesity prevention. Full article

Background: Warm reperfusion after previous cold storage has been shown to have a negative impact on mitochondrial function of organ grafts. Here, we wanted to investigate whether a more controlled warming up of the cold graft by ex vivo machine perfusion with gradually elevated temperature from cold to normothermia (including comparison of two warming up protocols) prior to implantation would be effective in preventing mitochondrial dysfunction upon reperfusion. Methods: All experiments were conducted on porcine kidneys retrieved 15 min after cardiac arrest. After 18 h of cold storage in HTK solution (CS, n = 6), kidneys (n = 6) were subjected to 2 h of reconditioning machine perfusion starting with a hypothermic period followed by a gradual increase in perfusion temperature up to 35 °C (controlled oxygenated rewarming—COR). For a second group (n = 6), the slow warming up was begun instantly after connecting the graft onto the machine (iCOR). Functional recovery of all grafts was then observed upon normothermic reperfusion in vitro. At the conclusion of the experiments, tissue specimens were taken for immediate isolation and analysis of renal mitochondria. Results: COR resulted in a significantly and more than 3-fold increased glomerular filtration rate upon reperfusion, along with a significant higher tubular sodium reabsorption and lesser loss of glucose in comparison to the controls. Enzyme release (AST) was also massively reduced during the reperfusion period. Specific analysis at the mitochondrial level revealed significantly better coupling efficiency and spare respiratory capacity in the COR group compared to the cold storage group. Interestingly, additional experiments revealed that the omission of a hypothermic perfusion period did not deteriorate any of the results after COR, provided that the instant temperature increase from 10 to 35 °C was effectuated in the same controlled manner. Conclusion: Controlled rewarming after extended cold preservation effectively improves mitochondrial recovery upon reperfusion and early functional outcome of kidney grafts. Full article

Cold storage remains the clinical standard for composite tissue preservation but is time-limited. A long ischemia time during surgery will adversely affect postoperative outcomes due to ischemia-reperfusion injury. Extracorporeal perfusion (ECP) seems to be a promising alternative for prolonged preservation, but more evidence is needed to support its use and to identify optimal perfusion fluids. This article assessed musculocutaneous flap vitality after prolonged ECP and compared outcomes after replantation to short static cold storage (SCS). Unilateral musculocutaneous rectus abdominis flaps were raised from 15 pigs and preserved by 4 h SCS (n = 5), 18 h mid-thermic ECP with Histidine–Tryptophan–Ketoglutarate (HTK, n = 5) or University of Wisconsin solution (UW, n = 5). Flaps were replanted and observed for 12 h. Skeletal muscle histology was assessed (score 0–12; high scores equal more damage), blood and perfusate samples were collected and weight was recorded as a marker for oedema. Mean histological scores were 4.0 after HTK preservation, 5.6 after UW perfusion and 5.0 after SCS (p = 0.366). Creatinine kinase (CK) was higher after ECP compared to SCS (p < 0.001). No weight increase was observed during UW perfusion, but increased 56% during HTK perfusion. Following 12 h reperfusion, mean weight gain reduced 39% in the HTK group and increased 24% in the UW group and 17% in the SCS group. To conclude, skeletal muscle seemed well preserved after 18 h ECP with HTK or UW perfusion, with comparable histological results to 4 h SCS upon short reperfusion. The high oedema rate during HTK perfusion remains a challenge that needs to be further addressed. Full article

Orthotopic liver transplantation (OLT) using allografts from donation after circulatory death (DCD) is potentially associated with compromised clinical outcomes due to ischemia-reperfusion injury (IRI)-induced organ damage and graft-related complications. The aim of this study was to provide in vivo data on the effects of adenosine A_2a receptor stimulation in a clinically relevant large animal model of DCD liver transplantation. Cardiac arrest was induced in German Landrace pigs (n = 10; 20–25 kg). After 30 min of warm ischemia, the donor liver was retrieved following a cold flush with 3 L of histidine-tryptophan-ketoglutarate-HTK solution. Animals of the treatment group (n = 5/group) received a standard dose of the selective adenosine receptor agonist CGS 21680 added to the cold flush. All grafts were stored for 4.5 h at 4 °C in HTK-solution before OLT. Hepatocellular injury, apoptosis, protein kinase A-PKA activity, graft microcirculation, liver function, and animal survival were assessed. Compared to untreated livers, adenosine A_2a receptor stimulation resulted in improved tissue microcirculation (103% ± 5% vs. 38% ± 4% compared to baseline; p < 0.05), accelerated functional recovery of the graft (indocyanine green-plasma disappearance rate (ICG-PDR) of 75% ± 18% vs. 40% ± 30% after 3 h), increased PKA activity ratio (56% ± 3% vs. 32% ± 3%; p < 0.001 after 1 h), and consequently reduced tissue necrosis and apoptosis. The potent protective effects were clinically manifested in significantly improved survival in the treatment group after 72 h (100% vs. 40%; p = 0.04). The ex vivo administration of adenosine A_2a receptor agonist during the back-table flush mitigates IRI-mediated tissue damage and improves functional graft recovery and survival in a large animal model of DCD liver transplantation. Full article

To ameliorate ischemia-induced graft injury, optimal organ preservation remains a critical hallmark event in solid organ transplantation. Although numerous preservation solutions are in use, they still have functional limitations. Here, we present a concise review of a modified Histidine-Tryptophan-Ketoglutarate (HTK) solution, named HTK-N. Its composition differs from standard HTK solution, carrying larger antioxidative capacity and providing inherent toxicity as well as improved tolerance to cold aiming to attenuate cold storage injury in organ transplantation. The amino acids glycine, alanine and arginine were supplemented, N-acetyl-histidine partially replaced histidine, and aspartate and lactobionate substituted chloride. Several in vitro studies confirmed the superiority of HTK-N in comparison to HTK, being tested in vivo in animal models for liver, kidney, pancreas, small bowel, heart and lung transplantation to adjust ingredients for required conditions, as well as to determine its innocuousness, applicability and potential advantages. HTK-N solution has proven to be advantageous especially in the preservation of liver and heart grafts in vivo and in vitro. Thus, ongoing clinical trials and further studies in large animal models and consequently in humans are inevitable to show its ability minimizing ischemia-induced graft injury in the sequel of organ transplantation. Full article