The Effect of Neutrophil-Derived Products on the Function of Leukocytes Obtained after Titanium Implantation in the Ovine Model

Titanium (Ti) is currently the most common biomaterial used for orthopedic implants; however, these implants may cause deleterious immune response. To investigate the possible mechanisms involved in excessive inflammation, we assessed the activity of neutrophils and monocyte-derived macrophages (MDMs) during the insertion of the Ti implant in a sheep model. The study was conducted on 12 sheep, 4 of which were control animals and 8 were in the experimental group with inserted Ti implant. Neutrophil secretory response was estimated at two time points T0 before surgery and T1 1 h after implantation and was based on the release of enzymes from neutrophil granules and reactive oxygen and nitrogen species (RONS) generation. MDM function was evaluated 5 months after implantation, on the basis of RONS generation arginase activity and morphological changes. Moreover, the influence of some autologous neutrophil derived products, namely, antimicrobial neutrophil extract (ANE) and neutrophil degranulation products (DGP) on leukocytes was estimated. Our study revealed that Ti implant insertion did not cause any adverse effects up to 5 months after surgical procedure. Stimulation of neutrophil cultures with ANE decreased the enzyme release as well as superoxide generation. Treatment of MDM with ANE diminished superoxide and NO generation and increased arginase activity. On the other hand, MDM stimulated with DGP showed elevated superoxide and NO generation as well as decreased arginase activity. To summarize, ANE exerted an anti-inflammatory and pro-resolving effect on studied leukocytes, whereas DGP acted as pro-inflammatory.

Preservation of Mitochondrial Coupling and Renal Function by Controlled Oxygenated Rewarming of Porcine Kidney Grafts

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.

Predictors of Mortality and Long-Term Outcome in Patients with Anterior STEMI: Results from a Single Center Study

Anterior ST segment elevation myocardial infarction (A-STEMI) has the worst prognosis among all infarct sites due to larger infarct size and the higher cardiac enzyme release. We retrospectively analyzed 584 A-STEMI undergoing urgent coronary angiography from October 2008 to April 2019. The median follow-up time was 1774 days with a minimum of a 1-year follow-up for 498 patients. In-hospital mortality was 8.6%, while long-term, all-cause mortality and 1-year mortality were 18.8% and 6.8%, respectively. The main predictors for in-hospital mortality were ejection fraction (LV-EF), baseline estimated glomerular filtration rate (eGFR), female gender and cardiogenic shock (CS) at admission, while long-term predictors of mortality were age, coronary artery disease (CAD) extension and LV-EF. Patients presenting with CS (6.5%) showed a higher mortality rate (in-hospital 68.4%, long term 41.7%). Among 245 patients (42%) with multivessel disease (MVD), complete revascularization (CR) during the index procedure was performed in 42.8% of patients and more often in patients with CS at admission (19.1% vs. 6.1%, p = 0.008). Short- and long-term mortality were not significantly influenced by the revascularization strategy (CR/culprit only). Our study confirmed the extreme fragility of A-STEMI patients, especially in case of CS at admission. LV-EF is a powerful predictor of a poor outcome. In MVD, CR during p-PCI did not show any advantage for either long- or short-term mortality compared to the culprit-only strategy.

Microbial cellulases immobilized in biopolymer/silica matrices used as enzyme release systems

Trichoderma viride CMGB 1 cellulases were immobilized by entrapment in silica gels (by sol-gel method), alginate biopolymers and hybrid alginate/silica materials. Tetramethoxysilane (TMOS), tetraethoxysilane (TEOS) and tetrakis (2-hydroxyethyl) orthosilicate (THEOS) were used as organoalkoxysilane precursors and ethanol or ethylene glycol as cosolvents in a two step sol-gel synthesis. Combined alginate/silica matrices resulted by mixing silica sol with sodium alginate or by coating alginate beads with a silica shell. The partial confinement of ethylene glycol in the matrix with consequences on biocatalytic activity was investigated using SEM-EDAX, thermal analysis and FT-IR spectroscopy. The efficiency of the enzyme-matrix biomaterials was tested in controlled enzyme release experiments. The sol-gel method developed using EG as a co-solvent allowed cellulase immobilization yields 1.5-4.5 times higher compared to classical sol-gel methods that use EtOH. The characterization of the gels by microscopic and spectrophotometric analyzes showed that there are similarities between the structure of the gels based on THEOS and those developed by us from TEOS, TMOS and EG as co-solvent. The new developed gels showed good cellulase release properties at acidic pH, comparable to those based on THEOS and alginate. The microbial cellulases immobilized in the matrices obtained and characterized in this work can operate as efficient systems for releasing enzymes, in acidic pH conditions, as feed additives.

Long-term cold storage preservation does not affect fatty livers from rats fed with a methionine and choline deficient diet

Background Waiting lists that continue to grow and the lack of organs available for transplantation necessitate the use of marginal livers, such as fatty livers. Since steatotic livers are more susceptible to damage from ischemia and reperfusion, it was investigated whether fatty livers with different lipidomic profiles show a different outcome when subjected to long-term cold storage preservation. Methods Eight-week-old male Wistar rats fed for 2 weeks by a methionine-choline-deficient (MCD) diet or control diet were employed in this study. Livers were preserved in a University of Wisconsin (UW) solution at 4 °C for 6, 12 or 24 h and, after washout, reperfused for 2 h with a Krebs-Henseleit buffer at 37 °C. Hepatic enzyme release, bile production, O2-uptake, and portal venous pressure (PVP) were evaluated. The liver fatty acid profile was evaluated by a gas chromatography-mass spectrometry (GC/MS). Results MCD rats showed higher LDH and AST levels with respect to the control group. When comparing MCD livers preserved for 6, 12 or 24 h, no differences in enzyme release were found during both the washout or the reperfusion period. The same trend occurred for O2-uptake, PVP, and bile flow. A general decrease in SFA and MUFA, except for oleic acid, and a decrease in PUFA, except for arachidonic, eicosadienoic, and docosahexanaeoic acids, were found in MCD rats when compared with control rats. Moreover, the ratio between SFA and the various types of unsaturated fatty acids (UFA) was significantly lower in MCD rats. Conclusions Although prolonged cold ischemia negatively affects the graft outcome, our data suggest that the quality of lipid constituents could influence liver injury during cold storage: the lack of an increased hepatic injury in MCD may be justified by low SFA, which likely reduces the deleterious tendency toward lipid crystallization occurring under cold ischemia.

Management of Takotsubo cardiomyopathy before non-cardiac surgery: A case report

Takotsubo cardiomyopathy (left ventricular apical balloon syndrome) is characterized by transient apical ballooning, leading to apical systolic dysfunction. This syndrome typically mimics acute coronary syndrome in terms of electrocardiographic changes and cardiac enzyme release. Although its exact pathophysiology is still unclear, it is thought to be due to stress related to the catecholaminergic discharge. It is usually seen on postmenopausal women. Herein, we report a 78-year-old female patient with Takotsubo cardiomyopathy admitted to the orthopedic surgery clinic due to a femoral fracture and had no complication after surgery.

Estrogen-Related Receptor γ Agonist DY131 Ameliorates Lipopolysaccharide-Induced Acute Liver Injury

Sepsis-associated liver dysfunction remains a challenge in clinical practice with high mortality and limited specific therapies. DY131 is a pharmacological agonist of the orphan receptor estrogen-related receptor (ERR) γ which plays a crucial role in regulating energy generation, oxidative metabolism, cell apoptosis, inflammatory responses, etc. However, its role in acute liver injury is unknown. In this study, we evaluated the effect of DY131 on lipopolysaccharide (LPS)-induced liver injury. Mice were pretreated with DY131 through intraperitoneal injection at a dose of 5 mg/kg/day for 3 days prior to LPS challenge (10 mg/kg). 24 h later, they were anesthetized and sacrificed. Blood and liver tissues were collected for further studies. In a separate experiment, mice were treated with saline (vehicle) or DY131 for 3 days to evaluate the toxicity of DY131. We found that ERRγ was downregulated in the liver tissues from LPS-treated mice. Pretreatment with DY131 ameliorated LPS-induced liver injury as demonstrated by reduced liver enzyme release (ALT, AST, and LDH), improved liver morphological damage, and attenuated oxidative stress, inflammation and apoptosis. Meanwhile, DY131 had no significant side effects on hepatic and renal functions in mice. Finally, transcriptomics analysis revealed that the dysregulated pathways associated with inflammation and metabolism were significantly reversed by DY131 in LPS-treated mice, providing more evidence in favor of the protective effect of DY131 against LPS-induced liver injury. Altogether, these findings highlighted the protective effect of DY131 on LPS-induced hepatotoxicity possibly via suppressing oxidative stress, inflammation, and apoptosis.

Influence of Supplementation of Lactoferrin, Melittin and Cecropin A to Rat Diet on Changes in Faecal Ammonia Concentrations, Short-Chain Fatty Acid Concentrations and Activities of Bacterial Enzymes

We hypothesised that the dietary addition of the bioactive antimicrobial protein lactoferrin (LF) and peptides melittin (MT) or cecropin A (CR) at a dosage of 100 mg/kg to the diet of Wistar rats would result in strong modulatory effects on faecal microbial enzymatic activity, short-chain fatty acid and ammonia concentrations. To date, the changes in bacterial extracellular and intracellular enzymatic activities upon addition of dietary AMPs have not yet been studied. This experiment lasted 15 days; during the first 5 day period, the rats were fed the control diet (S) and diets supplemented with LF, MT or CR. On days 6–15, all rats were fed the control S diet. The faecal fermentation processes were substantially stopped after two days of treatment, on average, in all rats receiving LF and two AMPs. The deepest suppression effect was observed on the last day of treatment (day 5) and persisted through days 5–8. The highest decreases in faecal bacterial β-glucosidase and β-glucuronidase activities as well as in SCFA and ammonia concentrations were observed in the rats fed the CR diet. Only in the CR animals did the mechanism of suppressed microbial fermentation involve diminished enzyme release from bacterial cells to the digesta.

Cardioplegia strategies

There are many cardioplegic strategies for coronary surgery. The goal is a dry operative field while maximizing myocardial recovery. Prospective randomized clinical trials have historically been difficult to achieve because of confounding variables such as solution used, route of administration, temperature, and so forth. This chapter describes an ‘integrated method’ of cardioplegia, so named because it combines many of the salient feature of various methods. It is designed to provide the maximum metabolic support of the myocardium during each phase of the operation. A vast literature from the laboratory to the bedside supports its use. Perhaps most importantly, integrated cardioplegia provides excellent protection of the septum and avoids paradoxical septal motion that may be a form of myocardial injury which is common with other methods of myocardial protection. Any future evaluation of cardioplegia methods should include not only survival but enzyme release and echocardiographic measurements of septal function.