Perfusion Solution Research Articles

Indocyanine green for leakage control in isolated limb perfusion

Abstract Objective Sarcomas are characterized by a high metastatic potential and aggressive growth. Despite surgery, chemotherapy plays an important role in the treatment of these tumors. Optimal anti-cancer therapy with maximized local efficacy and minimized systemic side effects has been the object of many studies for a long time. To improve the local efficacy of anti-tumor therapy, isolated limb perfusion with high-dose cytostatic agents has been introduced in surgical oncology. In order to control the local distribution of substances, radiolabeled cytostatic drugs or perfusion solutions have been applied but often require the presence of specialized personnel and result in a certain exposure to radiation. In this study, we present a novel strategy using indocyanine green to track tumor perfusion with high-dose cytostatic therapy. Methods In a rat cadaver model, the femoral vessels were cannulated and connected to a peristaltic pump to provide circulation within the selected limb. The perfusion solution contained indocyanine green and high-dose doxorubicin. An infrared camera enabled the visualization of indocyanine green during limb perfusion, and subsequent leakage control was successfully performed. Results Histologic analysis of sections derived proximally from the injection site excluded systemic drug dispersion. Conclusion In this study, the application of indocyanine green was proven to be a safe and cost- and time-efficient method for precise leakage control in isolated limb perfusion with a high-dose cytostatic agent.

Epileptiform Events and Kainate Receptor Activity Changes Considerably during Entorhinal Cortex Development: An ex vivo Study

Epilepsy is a commonly diagnosed neurological disease, which often develops already in childhood. The prominent feature of this dysfunction is the strong, unprovoked hypersynchronous neuronal activity of the brain, especially in the cortex, which appears in recurrent seizures. Previous studies indicated a potential modulatory role of kainate types of glutamate receptors in this mechanism. In our experiments, we used combined hippocampal-entorhinal rat brain slices of different ages. Developing (2-, 3-, and 4-week-old), adolescent (6-week-old), and adult (3-month-old) groups were investigated. During the experiments, first, we provoked convulsions with magnesium-free perfusion solution; then, to investigate the role of kainate receptors, seizure-like events (SLEs) were suppressed by applying a specific GluK1/2 antagonist (UBP-296). Neuronal network activity was recorded by a multi-electrode array chip, and temporal features of field potentials and single-cell activity were analyzed in the different age-groups. The frequency, duration of spontaneous events, the overall seizure characteristics, and spike activities were compared. Spontaneous events were categorized into interictal epileptiform discharges (IEDs) and SLEs on the basis of the temporal structure of activities. In 3- and 4-week-old animals, IEDs were observable, which entirely disappeared after the 4th week. The structure and the length of SLEs varied in the younger animals (3- and 4-week-old animals); however, after the 6th week, these events became more stabilized. In most groups, the count of detected spikes was significantly higher in layer II/III than in layer V. The neuronal networks started to behave like adult ones at 4 weeks of age. The length of events decreased in adult animals due to the maturation of the network, and the inhibition becomes stronger. The IEDs disappeared completely, and the SLEs became stable and stereotypic in 6-week-old animals. UBP-296 administration reduced the number of IEDs; however, this had no substantial effect on the SLEs.

Synergistic effects of trans-p-coumaric acid isolated from the ethanol extract of Gynura procumbens in promoting intestinal absorption of chlorogenic acid and reversing alcoholic fatty liver disease

Ethnopharmacological relevanceOur previous studies found that the ethanol extract of Gynura procumbens (EEGS) reduced hepatic steatosis in alcoholic fatty liver disease (AFLD). Aim of the studyTo explore the active ingredients from EEGS and their relevant mechanism of action in alleviating alcoholic liver injuries. Aim of the studyTo explore the active ingredients from EEGS and their intestinal absorption characteristics as an approach for understanding mechanism of action in alleviating alcoholic liver injuries. Materials and methodsMonitored by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC), chemical constituents from the prepared EEGS were isolated by means of solvent extraction, repeated column chromatography, preparative HPLC and other methods, and their structures were identified based on spectroscopic methods. The in vivo intestinal absorption rate of chlorogenic acid (CA), the active component of the EEGS, both in a single form and in the EEGS were monitored by the single-pass intestinal perfusion (SPIP) method in rats. The protective effect of EEGS and its active components on alcoholic liver injuries was evaluated in the alcoholic liver injury model of C57BL/6J male mice induced by Lieber-DeCarli alcohol liquid feed. ResultsThree noncaffeoyl quinic acid components were isolated and identified from the EEGS, namely, 3-trans-p-coumaroyl quinic acid (0.9%), 3-cis-p-coumaroyl quinic acid (2.7%), and trans-p-coumaric acid (0.6%). In vivo intestinal absorption of CA decreased with the increase of pH value of perfusion solution in the range of 5.5–7.8. The maximum absorption percentage of CA alone was 6.7 ± 2.4%, while the maximum absorption percentage of CA in the EEGS was 16.0 ± 2.2%, which was 2.4 times higher than that of CA alone. The results of animal experiments showed that the degree of fatty liver of mice treated with EEGS was significantly lower than that of the CA, trans-p-coumaric acid, and the combination group of CA and trans-p-coumaric acid alone. ConclusionThe above results indicated that trans-p-coumaric acid isolated from the dried stems of Gynura procumbens assisted CA being absorbed into the body and worked together with CA to improve the function of liver lipid metabolism, reduce hepatic lipid accumulation in a mouse model of AFLD and effectively counteract alcohol-induced fatty liver disease.

Endovascular Aneurysm Repair With Superior Mesenteric Artery Chimney and Renal Artery In Situ Laser Fenestration

Urgent and emergency situations require creative off-the-shelf solutions for complex aortic aneurysm repair. In situ laser fenestrated repair has been described to fill this need; however, there is a period of ischemia to the visceral vessels during endograft placement, laser fenestration, and bridging stent placement. This video shows a simplified approach that obviates the need for target vessel prestenting to demonstrate the origins for laser fenestration and facilitating renal protection with cold perfusion solution through the visceral sheaths during endograft coverage.

Determination of phenolic acids in Rehmannia glutinosa rhizosphere using a new method of microdialysis-HPLC

Microdialysis is an important technology in the field of medicine, and with the popularization and development of microdialysis technology, it has been gradually applied to the field of ecology. In this study, microdialysis-HPLC as a new and environmentally friendly in situ technique was developed and applied for the first time to detect phenolic acid allelochemicals in Rehmannia glutinosa rhizosphere. A response surface analysis (RSM) was used to optimize the microdialysis in situ based on the Box–Behnken design (BBD) experiment. The optimum dialysis conditions were obtained as follows: the perfusion solution was a NaCl solution of 200 mmol/L with pH 4, and the dialysis temperature was 37 °C. Under these conditions, the content of phenolic acids in the rhizosphere 10, 20 and 30 cm away from the root was analyzed using high-performance liquid chromatography (HPLC) detection combined with the standard curve of phenolic acid addition. Compared to traditional methods, microdialysis-HPLC is a simple and environmentally friendly method for the in situ detection of phenolic acids in rhizosphere.

Inhibition by acetazolamide of reactivated carbonic anhydrase activity in a receptor protein tyrosine phosphatase γ (RPTPγ) mutant

HCO3− reabsorption (JHCO3) by the renal proximal tubule (PT) is acutely regulated by basolateral [CO2]BL or [HCO3−]BL, but not by pHBL. RPTPγ is a transmembrane signaling protein expressed in the PT basal membrane and in many other sites throughout the body. Knocking out RPTPγ in mice renders JHCO3in isolated PTs insensitive to changes in [CO2]BL or [HCO3−]BL. Furthermore, RPTPγ knockout mice exhibit defective defense against a whole‐body metabolic acidosis. We therefore hypothesize that RPTPγ is a major CO2/HCO3− sensor in the tissues in which it is expressed. The extracellular ligand‐binding domain of RPTPγ shares 30% sequence identity to α‐type carbonic anhydrases (CAs). However, RPTPγ lacks (1) His residues at positions E149 and Q175 that participate in Zn2+ coordination in CAIV (CAIV equivalent residues, H115 and H140), and (2) the H+‐accepting His from the proton‐shuttle at the RPTPγ K122 position (CAIV residue H88). We measure extracellular surface pH (pHS) on Xenopus oocytes expressing wild‐type (WT) CAIV, RPTPg‐WT, and H2O‐injected controls. Upon switching the extracellular perfusing solution from a nominally CO2‐free ND96 solution to a 5% CO2/33mM HCO3− solution, the resulting CO2 influx causes pHS to rise, reflecting the consumption of H+ and HCO3− during the replenishment of CO2 at the cell surface. CO2 removal from the basolateral solution (“bath”) elicits the opposite effect on pHS. Consistent with prior work (Musa‐Aziz, Occhipinti & Boron. Am J Physiol, Cell Physiol 307: C814‐840, 2014), we find that CAIV increases pHS transient peak amplitude (ΔpHS) during the introduction of CO2/HCO3−. However, the ΔpHS of oocytes expressing RPTPγ‐WT is not significantly different from that measured from H2O‐injected control oocytes (n = 8 to 11; t‐test, p=0.517). We generated a mutant, in which we reconstituted 7 residues important for the catalysis (CO2 + H2O ⇌ H+ + HCO3−) by CAIV into the RPTPγ carbonic anhydrase‐like domain (CALD): T120N/K122H/A125N/E149H/Q175H/F177V/F178H (“CALD‐H”). Upon switching from ND96 (pH 7.5) to 5% CO2/33mM HCO3− (pH 7.5), the ΔpHS of oocytes expressing RPTPγ‐CALD‐H (0.330 ± 0.029; n = 12) is significantly increased vs RPTPγ‐WT (t‐test; p=3.1 × 10–7) and H2O control oocytes (t‐test; p=6.0 × 10–8). Moreover, when we add 100 mM acetazolamide (ACZ; an α‐type CA inhibitor) to the bath, the increased ΔpHS response (vs controls) of oocytes expressing either RPTPγ‐CALD‐H (0.062 ± 0.014; n = 12) or CAIV (0.077 ± 0.022; n = 7) is completely abolished (ANOVA; RPTPγ‐CALD‐H vs H2O: p=0.395; CAIV vs H2O: p=0.335). In conclusion, replacing 7 residues in RPTPγ‐CALD with their counterparts in CAIV is sufficient to re‐create CA activity. Moreover, ACZ blocks the re‐created CA activity of RPTPγ‐CALD‐H. This observation is of potential importance for the hypothesized role for WT‐RPTPγ in sensing [CO2] and [HCO3−], because it raises the possibility that sulfonamide drugs (prescribed for treating glaucoma or used as diuretics) could have the side effect inhibiting CO2/HCO3−sensing in the proximal tubule or other tissues.

Recent Methods of Kidney Storage and Therapeutic Possibilities of Transplant Kidney.

Kidney transplantation is the standard procedure for the treatment of end-stage renal disease (ESRD). During kidney storage and before implantation, the organ is exposed to damaging factors which affect the decline in condition. The arrest of blood circulation results in oxygen and nutrient deficiency that lead to changes in the cell metabolism from aerobic to anaerobic, damaging organelles and cell structures. Currently, most kidney grafts are kept in a cold preservation solution to preserve low metabolism. However, there are numerous reports that machine perfusion is a better solution for organ preservation before surgery. The superiority of machine perfusion was proved in the case of marginal donor grafts, such as extended criteria donors (ECD) and donation after circulatory death (DCD). Different variant of kidney machine perfusions are evaluated. Investigators look for optimal conditions to protect kidneys from ischemia-reperfusion damage consequences by examining the best temperature conditions and comparing systems with constant or pulsatile flow. Moreover, machine perfusion brings additional advantages in clinical practice. Unlike cold static storage, machine perfusion allows the monitoring of the parameters of organ function, which gives a real possibility to make a decision prior to transplantation concerning whether the kidney is suitable for implantation. Moreover, new pharmacological therapies are sought to minimize organ damage. New components or cellular therapies can be applied, since perfusion solution flows through the organ. This review outlines the pros and cons of each machine perfusion technique and summarizes the latest achievements in the context of kidney transplantation using machine perfusion systems.

Lung Function and Inflammatory Profiling of Damaged Rat Donor Lungs Following EVLP Heat Stress with Different Temperatures

<h3>Purpose</h3> Ex-vivo lung perfusion (EVLP) is a validated technique allowing evaluation and reconditioning of damaged donor lungs to make them suitable for lung transplantation. Moderate hyperthermia is known to exert cytoprotective effect, via induction and accumulation of specific proteins, known as heat shock proteins (HSPs). We hypothesized that thermal preconditioning (TP) with a well-calibrated heat stress applied during EVLP could improve lung graft by reduction of oxidative stress, cell death and inflammation. <h3>Methods</h3> Male rats were randomly assigned into 5 groups: controls (Ctrl, n=5) and four heat stress groups (HS of 41.5°C; 42.0°C; 42.5°C or 43.5°C, n=5). In all groups, lungs were kept <i>in situ</i> for 1h at room temperature, then flushed with cold Perfadex. Heart-lung block was harvested and kept at 4°C for 1h, then mounted on the EVLP system for 3h. In Ctrl group, the temperature perfusion solution was kept at 37°C the all-time. In the HS groups, a heat shock was done for 30 minutes after 1h of EVLP by heating the perfusion solution at different temperature. At the end of EVLP, lungs were snap-frozen and kept at -80°C for further tissue analysis. <h3>Results</h3> Static pulmonary compliance SPC ratio (180 min to 60 min of EVLP) was significantly increased in the 41.5°C group compared to Ctrl group, while it was significantly reduced in 43.5°C group. The weight gain was significantly reduced in 41.5°C, whereas increased in 43.5°C group. In all HS groups, except in 43.5°C, protein levels of inducible HSP72 and Heme oxygenase-1 (HO-1) were significantly increased compared to Ctrl. Reduction of caspase 3 activation (apoptosis marker) was seen in all groups but reached significant level only in 41.5°C and 43.5°C groups. In all HS groups, we could see a reduction of inflammatory mediators such as, IL-1α, IL-1β, and TNF-α, a reduction of the release of CC16 (a marker of lung epithelial injury), as well as a reduction of IL-1β in Steen solution. <h3>Conclusion</h3> Thermal preconditioning during EVLP can decrease apoptotic cell death and inflammation of damaged lungs. These findings demonstrate that EVLP in association with well calibrated thermal preconditioning (41.5°C) could be a promising therapeutic platform improving lung quality of damaged donor lungs.

Lung Function and Inflammatory Profiling of Damaged Rat Donor Lungs Following EVLP Thermal Preconditioning

<h3>Purpose</h3> Ex-vivo lung perfusion (EVLP) is a validated technique allowing evaluation and reconditioning of damaged donor lungs to make them suitable for transplantation. Moderate hyperthermia is known to exert cytoprotective effect, via induction and accumulation of specific proteins, known as heat shock proteins (HSPs). We hypothesized that thermal preconditioning (TP) with a well-calibrated heat stress applied during EVLP could improve lung graft by reduction of oxidative stress, cell death and inflammation. <h3>Methods</h3> Male rats were randomly assigned into 2 groups: controls (Ctrl, n=5) or TP (n=5). In both groups, lungs were kept <i>in situ</i> for 1h at room temperature, then flushed with cold Perfadex. Heart-lung block was harvested and kept at 4°C for 1h, then mounted on the EVLP system for 3h. In Ctrl group, the temperature perfusion solution was kept at 37°C the all-time. In the TP group, a heat shock was done for 30 minutes after 1h of EVLP by heating the perfusion solution at 41.5°C. At the end of EVLP, lungs were snap-frozen and kept at -80°C for further tissue analysis. <h3>Results</h3> Static pulmonary compliance, peak inspiratory pressure, and oxygenation capacity were similar in both groups. We were able to induce HSPs in the TP group (<i>Hspa1a</i> and <i>Hmox-1</i>). In the TP group, we observed a reduction of oxidative stress (carbonyls and MDA), a decrease of apoptosis (Caspase 3 and 7) and a decrease of pro-inflammatory NF-κB transcription factor as well as the expression of inflammation mediators such as TNF-α, IL-1α, IL-1β, CXCL-1 and CCL-2. <h3>Conclusion</h3> Thermal preconditioning during EVLP decreased oxidative stress, apoptotic cell death, and inflammation of damaged lungs. These findings demonstrate that EVLP in association with thermal preconditioning could be a promising therapeutic platform improving lung quality of damaged donor lungs.

Cold or Not So Cold?-Static Organ Preservation at 10 °C May Prolong Organ Preservation and Facilitate Transplant Logistics.

Cold or Not So Cold?-Static Organ Preservation at 10 °C May Prolong Organ Preservation and Facilitate Transplant Logistics.

Assessment of machine perfusion conditions for the donation after circulatory death heart preservation.

BackgroundDonation after circulatory death (DCD) hearts requires machine perfusion preservation, the conditions of which are not well defined.MethodsTo achieve this, rat hearts were procured following a DCD or control beating‐heart donation (CBD) model, and perfused for 60 min with one of three machine perfusion solutions—St. Thomas (ST), University of Wisconsin (UW), or Polyethylene Glycol‐20k (PEG)—at one of two temperatures, 4°C or 15°C. At 15‐min intervals, perfusion pressure was measured as a marker of vascular resistance. Colored microspheres were added to capture the distribution of perfusate into the metabolically active sub‐endocardium, and the eluate was collected for troponin assays. Analyses compared groups using Wilcoxon rank‐sum and ANOVA.ResultsPerfusion pressure was significantly higher for DCD than CBD hearts at 15°C regardless of solutions. The lowest rise in perfusion pressure over time was observed with PEG at 15°C. Except for PEG at 15°C, ST and UW solutions at 4 or 15°C had decreased sub‐endocardial perfusion in DCD hearts. Troponin release from DCD hearts with UW and PEG solutions was comparable to CBD hearts but was significantly higher with ST solution at 15°C.ConclusionsOptimal preservation conditions for DCD hearts were observed with PEG machine perfusion solution at 15°C.

24-hour Perfusion of Porcine Myocutaneous Flaps Mitigates Reperfusion Injury: A 7-day Follow-up Study.

Background:Static cold storage is the gold standard of preservation in vascularized composite allotransplantation and allows a preservation time of 4–6 hours. Machine preservation is a promising technique for prolonged preservation; however, studies on extended preservation that compare different preservatives are scarce. This study aims to assess the feasibility of 24-hour acellular perfusion and compares different preservation solutions in a porcine myocutaneous flap replantation model.Methods:Six harvested bilateral myocutaneous flaps of three Dutch Landrace pigs were perfused hypothermically for 24 hours with University of Wisconsin machine perfusion solution (UW-MPS; n = 2) or histidine-tryptophan-ketoglutarate solution (HTK; n = 2) or preserved on ice for 4 hours (n = 2) before orthotopic replantation. Animals were observed for 7 days after replantation. Skeletal muscle injury was assessed by biochemical markers during perfusion, and muscle biopsies were analyzed for ischemia reperfusion injury directly after preservation and at 1, 3, and 7 days after replantation.Results:Markers of muscle damage varied during perfusion, but decreased overall in both perfusion groups. Flap weight increased 60% and 97% in the HTK-perfused flaps, compared with -6% and -7% in the UW-MPS-perfused flaps after 24 hours. Histopathologic evaluation demonstrated decreased muscle damage in flaps perfused with HTK compared with the UW-MPS-perfused flaps at 1 week after replantation.Conclusions:Machine perfusion of myocutaneous flaps for 24 hours with subsequent replantation is feasible, but warrants further research. Perfusion with HTK solution seemed to result in better histological outcomes 7 days after reperfusion compared with UW-MPS.

Ex vivo enzymatic treatment converts blood type A donor lungs into universal blood type lungs.

Donor organ allocation is dependent on ABO matching, restricting the opportunity for some patients to receive a life-saving transplant. The enzymes FpGalNAc deacetylase and FpGalactosaminidase, used in combination, have been described to effectively convert group A (ABO-A) red blood cells (RBCs) to group O (ABO-O). Here, we study the safety and preclinical efficacy of using these enzymes to remove A antigen (A-Ag) from human donor lungs using ex vivo lung perfusion (EVLP). First, the ability of these enzymes to remove A-Ag in organ perfusate solutions was examined on five human ABO-A1 RBC samples and three human aortae after static incubation. The enzymes removed greater than 99 and 90% A-Ag from RBCs and aortae, respectively, at concentrations as low as 1 μg/ml. Eight ABO-A1 human lungs were then treated by EVLP. Baseline analyses of A-Ag in lungs revealed expression predominantly in the endothelial and epithelial cells. EVLP of lungs with enzyme-containing perfusate removed over 97% of endothelial A-Ag within 4 hours. No treatment-related acute lung toxicity was observed. An ABO-incompatible transplant was then simulated with an ex vivo model of antibody-mediated rejection using ABO-O plasma as the surrogate for the recipient circulation using three donor lungs. The treatment of donor lungs minimized antibody binding, complement deposition, and antibody-mediated injury as compared with control lungs. These results show that depletion of donor lung A-Ag can be achieved with EVLP treatment. This strategy has the potential to expand ABO-incompatible lung transplantation and lead to improvements in fairness of organ allocation.

Propofol Regulates the Expression of BecliN-1 through miR-30b and Protects against Lung Ischemia-Reperfusion Injury.

Pulmonary ischemia-reperfusion can cause severe dysfunction of alveolar epithelium and alveolar cells. Drugs such as propofol have a protective effect on lung ischemia-reperfusion, but this protective mechanism is not stable and requires other factors such as nucleosides. The purpose of this article is to study the protective mechanism of propofol on lung ischemia-reperfusion injury by regulating the expression of BecliN-1 by miR-30b. With 72 male rats as the research object, a rat lung ischemia-reperfusion model was established. Phenol agents were perfused as the perfusion solution to detect the expression levels of miR-30b and BecliN-1, statistical experimental data and analyze the regulatory mechanism of miR-30b on the expression of BecliN-1 and the effect of propofol on the protection of lung ischemia-reperfusion. Research results show that propofol can reduce inflammation, reduce oxidative stress, inhibit lung tissue apoptosis, improve lung function and pathological changes of lung tissue by inhibiting the activation of the JAK-STAT signaling pathway, and propofol can pass. The protection of miR-30b's regulation of BecliN-1 expression against lung ischemia-reperfusion injury is 30% higher than that of other protective mechanisms. At the same time, the apoptosis rate of inflammatory lung tissue cells is reduced by 13%.

Diclofenac in vitro microdialysis study comparing different experimental set-ups to improve quantitative recovery.

Several studies investigated diclofenac tissue concentrations using microdialysis (MD). However, thorough evaluations of the optimal MD set‐up for diclofenac are unavailable. Thus, this in vitro MD study aimed to compare different set‐ups to improve quantitative recovery of diclofenac. In forward and reverse in vitro MD experiments with diclofenac at two concentrations (1 and 100 ng/ml), the perfusion solutions physiological saline 0.9% (PS) and human albumin 1% (HSA) were compared using tissue probes (10‐mm membrane) and customized intravenous (iv) probes (30‐mm membrane). Using PS, the mean relative recovery of diclofenac at 1 ng/ml was 1.6% ± 0.04% and 3.12% ± 0.00% with the tissue probe and the iv probe, respectively. The respective mean relative recovery for diclofenac at 100 ng/ml was 0.02% ± 0.01% and 0.21% ± 0.11%. Using HSA, the mean relative recovery was 314% ± 25% (tissue probe) and 1064% ± 97% (iv probe) for diclofenac at 1 ng/ml and 444% ± 91% and 1415% ± 217% for diclofenac at 100 ng/ml. In reverse dialysis using PS, the mean relative loss of diclofenac was 99.2% ± 0.5% (tissue probe) and 95.8% ± 1.7% (iv probe). Using HSA, the mean relative loss was −4.4% ± 7.2% and 0.2% ± 7.5%, respectively. PS and HSA were not suitable perfusion solutions for quantification of absolute diclofenac concentrations. Despite methodological challenges, HSA may be used for comparative experiments or bioequivalence studies.

Полікомпонентні колоїдно-гіперосмолярні розчини як ефективний компонент інфузійної терапії у хворих на гострий панкреатит

Стаття присвячена одному з найбільш тяжких та прогностично несприятливих гострих захворювань органів черевної порожнини — гострому панкреатиту. Наведені дані дослідження клінічної ефективності та ролі перфузійних розчинів у комплексному хірургічному лікуванні хворих із гострим панкреатитом на ранньому етапі лікування. Отримані результати дозволили зробити висновок, що включення перфузійних розчинів гідроксіетилкрохмалю у схему корекції гіповолемічних порушень сприяє стабілізації стану пацієнтів, чинить мікроциркулярний ефект та забезпечує раннє відновлення перистальтики.

Shifting Paradigms for Suppressing Fibrosis in Kidney Transplants: Supplementing Perfusion Solutions With Anti-fibrotic Drugs.

Great efforts have been made toward addressing the demand for donor kidneys. One of the most promising approaches is to use kidneys from donation after circulatory death donors. These kidneys, however, suffer from more severe ischemia and reperfusion injury than those obtained via donation after brain death and are thus more prone to develop interstitial fibrosis and tubular atrophy. Even though machine perfusion is increasingly used to reduce ischemia and reperfusion injury, there are no effective treatments available to ameliorate interstitial fibrosis and tubular atrophy, forcing patients to resume dialysis, undergo re-transplantation, or suffer from premature death. Safe and effective anti-fibrotic therapies are therefore greatly desired. We propose a new therapeutic approach in which machine perfusion solutions are supplemented with anti-fibrotic compounds. This allows the use of higher concentrations than those used in humans whilst eliminating side effects in other organs. To the authors' knowledge, no one has reviewed whether such an approach could reduce interstitial fibrosis and tubular atrophy; we therefore set out to explore its merit. In this review, we first provide background information on ischemia and reperfusion injury as well as interstitial fibrosis and tubular atrophy, after which we describe currently available approaches for preserving donor kidneys. We then present an evaluation of selected compounds. To identify promising compounds, we analyzed publications describing the effects of anti-fibrotic molecules in precision-cut kidneys slices, which are viable explants that can be cultured ex vivo for up to a few days whilst retaining functional and structural features. LY2109761, galunisertib, imatinib, nintedanib, and butaprost were shown to exert anti-fibrotic effects in slices within a relatively short timeframe (<48 h) and are therefore considered to be excellent candidates for follow-up ex vivo machine perfusion studies.

Preparation and intestinal absorption of Panax notoginseng saponins chitosan nanoparticles

In this experiment, Panax notoginseng saponins chitosan nanoparticles(PNS-NPs) were prepared by self-assembly and their appearance, particle size, encapsulation efficiency, drug loading, polydispersity index(PDI), Zeta potential, and microstructure were characterized. The prepared PNS-NPs were intact in structure, with an average particle size of(209±0.258) nm, encapsulation efficiency of 42.34%±0.28%, a drug loading of 37.63%±0.85%, and a Zeta potential of(39.8±3.122) mV. The intestinal absorption of PNS-NPs in rats was further studied. The established HPLC method of PNS was employed to investigate the effects of pH, perfusion rate, and different drugs(PNS raw materials, Xuesaitong Capsules, and PNS-NPs). The absorption rate constant(K_a) and apparent permeability coefficient(P_(app)) in the duodenum, jejunum, ileum, and colon were calculated and analyzed. As illustrated by the results, the intestinal absorption of PNS-NPs was increased in the perfusion solution at pH 6.8(P&lt;0.05), and perfusion rate had no significant effect on the K_a and P_(app) of PNS-NPs. The intestinal absorption of PNS-NPs was significantly different from that of PNS raw materials and Xuesaitong Capsules(P&lt;0.05), and the intestinal absorption of PNS-NPs was significantly improved.

Non-heat-stressed Method to Isolate Hepatic Stellate Cells From Highly Steatotic Tumor-bearing Liver Using CD49a.

Non-heat-stressed Method to Isolate Hepatic Stellate Cells From Highly Steatotic Tumor-bearing Liver Using CD49a.

IGL-2 as a Unique Solution for Cold Static Preservation and Machine Perfusion in Liver and Mitochondrial Protection

Hypothermic static cold storage and machine perfusion strategies remain the clinical standard of care for liver graft preservation. Recently, the protection of the mitochondrial function and the energetic levels derived from it has emerged as one of the key points for organ preservation. However, the complex interactions between liver mitochondrial protection and its relation with the use of solutions/perfusates has been poorly investigated. The use of an alternative IGL-2 solution to Belzer MPS one for hypothermic oxygenated perfusion (HOPE), as well as in static cold storage, introduce a new kind of perfusate to be used for liver grafts subjected to HOPE strategies, either alone or in combination with hypothermic static preservation strategies. IGL-2 not only protected mitochondrial integrity, but also avoided the mixture of different solutions/perfusates reducing. Thus, the operational logistics and times prior to transplantation, a critical factor when suboptimal organs such as donation after circulatory death or steatotic ones, are used for transplantation. The future challenges in graft preservation will go through (1) the improvement of the mitochondrial status and its energetic status during the ischemia and (2) the development of strategies to reduce ischemic times at low temperatures, which should translate in a better transplantation outcome.