Immune-Mediated Liver Effects Associated With Administration of a Human Anti-IL-21 Receptor Antibody (ATR-107) in Rats.

The toxicity of ATR-107, a human anti-interleukin-21 receptor (IL-21R) monoclonal antibody (mAb), was evaluated in CD-1 mice and cynomolgus monkeys after single-dose intravenous (IV) administration, and in Sprague-Dawley (SD) rats and cynomolgus monkeys after weekly IV and subcutaneous (SC) administration in 13-week toxicity studies that included recovery. Adverse liver necrosis, diffuse bridging fibrosis, and higher liver enzymes occurred in rats in the low-dose IV group (10 mg/kg), but not at 50 or 250 mg/kg IV, and not following SC administration despite overlapping systemic ATR-107 exposures. Similar findings were not seen in mice or cynomolgus monkeys. A series of investigative rat toxicity studies showed liver findings only occurred after administration of at least 3 weekly doses, only occurred in rats that developed anti-drug antibodies (ADAs), and the incidence was associated with higher ADAs titers. However, the presence of ADAs did not always result in liver injury. Liver findings did not occur in nude rats, which had high ATR-107 exposures and no ADAs. These findings suggest an adaptive immune response with formation of ADAs was necessary for development of ATR-107-related liver findings, and that liver injury can occur in rats secondary to development of ADAs following repeated administration of a human therapeutic mAb.

The pyrrolizidine alkaloid senecionine induces CYP-dependent destruction of sinusoidal endothelial cells and cholestasis in mice.

Pyrrolizidine alkaloids (PAs) are widely occurring phytotoxins which can induce severe liver damage in humans and other mammalian species by mechanisms that are not fully understood. Therefore, we investigated the development of PA hepatotoxicity in vivo, using an acutely toxic dose of the PA senecionine in mice, in combination with intravital two-photon microscopy, histology, clinical chemistry, and in vitro experiments with primary mouse hepatocytes and liver sinusoidal endothelial cells (LSECs). We observed pericentral LSEC necrosis together with elevated sinusoidal marker proteins in the serum of senecionine-treated mice and increased sinusoidal platelet aggregation in the damaged tissue regions. In vitro experiments showed no cytotoxicity to freshly isolated LSECs up to 500 µM senecionine. However, metabolic activation of senecionine by preincubation with primary mouse hepatocytes increased the cytotoxicity to cultivated LSECs with an EC50 of approximately 22 µM. The cytochrome P450 (CYP)-dependency of senecionine bioactivation was confirmed in CYP reductase-deficient mice where no PA-induced hepatotoxicity was observed. Therefore, toxic metabolites of senecionine are generated by hepatic CYPs, and may be partially released from hepatocytes leading to destruction of LSECs in the pericentral region of the liver lobules. Analysis of hepatic bile salt transport by intravital two-photon imaging revealed a delayed uptake of a fluorescent bile salt analogue from the hepatic sinusoids into hepatocytes and delayed elimination. This was accompanied by transcriptional deregulation of hepatic bile salt transporters like Abcb11 or Abcc1. In conclusion, senecionine destroys LSECs although the toxic metabolite is formed in a CYP-dependent manner in the adjacent pericentral hepatocytes.

Pathophysiological Mechanism of Extravasation via Umbilical Venous Catheters.

A rare complication of umbilical venous catheter (UVC) insertion is the extravasation of the infusate into the peritoneal cavity. We report 3 cases of abdominal extravasation of parenteral nutrition (PN) fluid via UVCs. Two of these cases presented as "acute abdomen" which were assumed to be necrotizing enterocolitis clinically; however, during postmortem, PN ascites and liver necrosis were found. A further case is described in an infant with congenital diaphragmatic hernia. While we were unable to ascertain direct vessel perforation by the catheter in any of these cases, based on pathological and histological examination, the proposed mechanism of PN fluid extravasation is leakage through microinjuries of liver vessel walls and necrotic parenchyma. PN extravasation should be considered as a differential diagnosis of acute abdomen when PN is infused via an UVC presumably as PN may have a direct irritant effect on the peritoneum.

IL-33 signalling in liver immune cells enhances drug-induced liver injury and inflammation.

OBJECTIVE AND DESIGN: The aim of this study was to investigate the contribution of IL-33/ST2 axis in the onset and progression of acute liver injury using a mice model of drug-induced liver injury (DILI). MATERIAL AND TREATMENTS: DILI was induced by overdose administration of acetaminophen (APAP) by oral gavage in wild-type BALB/c, ST2-deficient mice and in different bone marrow chimeras. Neutrophils were depleted by anti-Ly6G and macrophages with clodronate liposomes (CLL). METHODS: Blood and liver were collected for biochemical, immunologic and genetic analyses. Mice were imaged by confocal intravital microscopy and liver non-parenchymal cells and hepatocytes were isolated for flow cytometry, genetic and immunofluorescence studies. RESULTS: Acetaminophen overdose caused a massive necrosis and accumulation of immune cells within the liver, concomitantly with IL-33 and chemokine release. Liver non-parenchymal cells were the major sensors for IL-33, and amongst them, neutrophils were the major players in amplification of the inflammatory response triggered by IL-33/ST2 signalling pathway. CONCLUSION: Blockage of IL-33/ST2 axis reduces APAP-mediated organ injury by dampening liver chemokine release and activation of resident and infiltrating liver non-parenchymal cells.

Temporary liver and stomach necrosis after lateral approach for interbody fusion and deformity correction of lumbar spine: report of two cases and review of the literature.

INTRODUCTION: Corrections of spinal deformities have been associated with a potential of postoperative vessel-originating complications. Reports of occlusions of celiac artery seem though to be very rare. CASE REPORTS: We present two cases that developed acute arterial supply impairment and subsequent liver and gastric necrosis due to an occlusion of celiac artery, after a spine deformity correction. In both patients a lateral surgical approach to the superior lumbar spine, lateral placement of cages and then a subsequent posterior fixation were performed. REVIEW: The literature search reveals the report of three similar cases, with potentially different pathogenetic mechanisms and with a different prognosis. This complication is assumed to occur due to a Medial Arcuate Ligament syndrome (MALS) developed postoperatively that leaded to compression of the celiac artery against the Medial Arcuate Ligament. The pathogenesis though remains unclear and two theories are assumed to explain the acute appearance of the syndrome; the alteration of the anatomic relationship between the vessels and the surrounding tissues due to the spine deformity correction and an intraoperative direct or indirect traction injury of the celiac trunk that caused or increased its pressure against the medial arcuate ligament. CONCLUSION: The spine surgeon should be aware of the possibility of postoperative ischemia of the liver and stomach by occlusion of the celiac artery or its supplying branches. Specifically when a large correction of a kyphotic/kyphoscoliotic spine is planed, the surgeon should be alert for an appearance of a MALS.

Plasma osteopontin in acute liver failure.

BACKGROUND: Osteopontin (OPN) is a novel phosphoglycoprotein expressed in Kupffer cells that plays a pivotal role in activating natural killer cells, neutrophils and macrophages. Measuring plasma OPN levels in patients with acute liver failure (ALF) might provide insights into OPN function in the setting of massive hepatocyte injury. METHODS: OPN levels were measured using a Quantikine® ELISA assay on plasma from 105 consecutive ALF patients enrolled by the US Acute Liver Failure Study Group, as well as controls including 40 with rheumatoid arthritis (RA) and 35 healthy subjects both before, and 1 and 3 days after undergoing spine fusion (SF) surgery as a model for acute inflammation. RESULTS: Median plasma OPN levels across all etiologies of ALF patients were elevated 10- to 30-fold: overall median 1055ng/mL; range: 33-19,127), when compared to healthy controls (median in pre-SF patients: 41ng/mL; range 2.6-86.4). RA and SF post op patients had elevated OPN levels (37ng/mL and 198ng/mL respectively), well below those of the ALF patients. Median OPN levels were highest in acetaminophen (3603ng/mL) and ischemia-related ALF (4102ng/mL) as opposed to viral hepatitis (706ng/mL), drug-induced liver injury (353ng/mL) or autoimmune hepatitis (436ng/mL), correlating with the degree of hepatocellular damage, as reflected by aminotransferase values (R value: 0.47 for AST, p<0.001). CONCLUSIONS: OPN levels appeared to correlate with degree of liver necrosis in ALF. Very high levels were associated with hyperacute injury and good outcomes. Whether OPN exerts a protective effect in limiting disease progression in this setting remains uncertain.

Safety of deferasirox: a retrospective cohort study on the risks of gastrointestinal, liver and renal events.

BACKGROUND: Deferasirox (DFX) is an effective and well-tolerated oral iron chelator elevating the adherence to iron chelating therapy among patients with iron overload. However, the US Food and Drug Administration issued a warning about the potential adverse events associated with DFX in 2010. METHODS: To examine the risks of gastrointestinal (GI) bleeding, acute liver necrosis, and acute renal failure among DFX users compared with desferrioxamine (DFO) users in a real-world setting, first-time users of DFX or DFO between 2005 and 2008 in Taiwan's National Health Insurance database were observed in this population-based retrospective cohort study. The risks of different adverse events were individually analyzed by Cox proportional hazards models and adjusted by age, sex, concomitant medications, and prior medical conditions. RESULTS: Deferasirox users had the highest incidence rates of GI bleeding (2.03 per 10 000 patient-days), acute liver necrosis (0.26 per 10 000 patient-days) and acute renal failure (1.45 per 10 000 patient-days) compared with other iron chelator users. Compared with DFO users, DFX users were not associated with the risk of GI bleeding (adjusted HR 1.03, 95% CI 0.61-1.74, p = 0.90) and the risk of acute liver necrosis (adjusted HR 2.13, 95% CI 0.49-9.33, p = 0.32). The association between DFX use and acute renal failure was found to be statistically significant (HR 2.18, 95% CI 1.18-4.02, p = 0.01; adjusted HR 2.41, 95% CI 1.27-4.58, p = 0.01). CONCLUSION: In this study, we found statistically significant higher risk of acute renal failure and non-statistically significant higher risk of GI bleeding and acute liver necrosis associated with DFX use. More researches are warranted to evaluate the association between DFX use and potential adverse events.

Hepatic damage caused by flaviviruses: A systematic review.

Flaviviruses infect arthropods and mammals and their pathologies are a considerable global health problem, affecting about 400 million people per year. The symptoms of these flaviviruses range from mild manifestations such as nausea, vomiting, and headache to more serious cases such as hemorrhage, meningitis, microcephaly, kidney, and liver failure. This review aims to compile the morphological changes that occur due to infections caused by dengue, yellow fever, and Zika viruses, as well as to describe possible mechanisms of action of such flaviviruses in the liver. PRISMA guidelines were used to search for studies associating flavivirus with liver disorders. Two independent reviewers selected the studies on PubMed/Medline, Web of Science, and Scopus search platforms. The SYRCLE software was used for the evaluation of the study's quality. Eighteen experimental articles were included. The experimental animals often used in experiments were monkeys (5 %), hamsters (10 %), chicken embryos (10 %), and mice (75 %). It is evident that there is a strong hepatic interaction with flaviviruses, and the main hepatic alterations found were steatosis, apoptosis, necrosis, hemorrhage, elevation of ALT and AST levels, and total bilirubin. Flavivirus infection, in general, trigger an upregulation of pro-inflammatory cytokines, leading to structural changes in mitochondria that activate cascades of cellular death and promote insulin resistance. The majority of the studies primarily focus on dengue and yellow fever viruses, while the findings related to Zika virus exposure are still relatively limited and require further investigation.

Molecular mechanisms in thioacetamide-induced acute and chronic liver injury models.

Thioacetamide (TAA) undergoes bioactivation in the liver by the CYP450 2E1 enzyme, resulting in the formation of TAA-S-oxide and TAA-S-dioxide. TAA-S-dioxide induces oxidative stress via lipid peroxidation of the hepatocellular membrane. A single TAA dose (50-300 mg/kg) administration initiates hepatocellular necrosis around the pericentral region after its covalent binding to macromolecules in the liver. Intermittent TAA administration (150-300 mg/kg, weekly thrice, for 11-16 weeks) activates transforming growth factor (TGF)-ß/smad3 downstream signaling in injured hepatocytes, causing hepatic stellate cells (HSCs) to acquire myofibroblast like phenotype. The activated HSCs synthesize a variety of extracellular matrix, leading to liver fibrosis, cirrhosis, and portal hypertension. The TAA induced liver injury varies depending on the animal model, dosage, frequency, and routes of administration. However, TAA induces hepatotoxicity in a reproducible manner, and it is an ideal model to evaluate the antioxidant, cytoprotective, and antifibrotic compounds in experimental animals.

Ribociclib-induced liver injury: a case report.

Background: Idiosyncratic drug-induced liver injury (DILI) is a rare, unpredictable hepatic adverse event and the most common cause of acute liver failure in Europe and the US. Ribociclib is a potent Cyclin-dependent kinase 4 and 6 (CDK4/6)-inhibitor administered for advanced hormone-receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Previous reports have shown hepatotoxicity without liver necrosis related to ribociclib. Case presentation: A 41-year-old female patient with primary metastatic HR-positive, HER2-negative breast cancer developed liver enzyme elevation under treatment with ribociclib. Ribociclib was withdrawn 8 weeks after initiation due to liver enzyme elevation. A liver biopsy, performed due to further enzyme increase (peak ALT 2836 U/l), onset of jaundice (peak bilirubin 353 µmol/l) and coagulopathy (INR 1.8) two weeks later, revealed acute hepatitis with 30% parenchymal necrosis. Roussel Uclaf Causality Assessment Method (RUCAM) score was 7 points (probable). Under treatment with prednisone (60mg), initiated 2 weeks after drug withdrawal, and subsequently N-acetylcysteine (Prescott regimen) liver enzymes normalized within 8 weeks along with prednisone tapering. Conclusion: This case illustrates the development of a severe idiosyncratic hepatocellular pattern DILI grade 3 (International DILI Expert Working Group) induced by ribociclib. Routine liver enzyme testing during therapy, immediate hepatologic work-up and treatment interruption in case of liver enzyme elevation are highly recommended. Corticosteroid treatment should be considered in cases of severe necroinflammation.

The novel cyclophilin inhibitor C105SR reduces hepatic ischaemia-reperfusion injury via mitoprotection.

Background & Aims: Mitochondrial permeability transition pore (mPTP) opening is critical for mediating cell death during hepatic ischaemia-reperfusion injury (IRI). Blocking mPTP opening by inhibiting cyclophilin D (CypD) is a promising pharmacological approach for the treatment of IRI. Here, we show that diastereoisomers of a new class of small-molecule cyclophilin inhibitors (SMCypIs) have properties that make them attractive candidates for the development of therapeutic agents against liver IRI. Methods: Derivatives of the parent SMCypI were synthesised and evaluated for their ability to inhibit CypD peptidyl-prolyl cis-trans isomerase (PPIase) activity and for their mitoprotective properties, evaluated by measuring mitochondrial swelling and calcium retention capacity in liver mitochondria. The ability of the selected compounds to inhibit mPTP opening was evaluated in cells subjected to hypoxia/reoxygenation using a calcein/cobalt assay. Their ability to inhibit cell death was evaluated in cells subjected to hypoxia/reoxygenation by measuring lactate dehydrogenase (LDH) release, propidium iodide staining, and cell viability. The compound performing best in vitro was selected for in vivo efficacy evaluation in a mouse model of hepatic IRI. Results: The two compounds that showed the strongest inhibition of CypD PPIase activity and mPTP opening, C105 and C110, were selected. Their SR diastereoisomers carried the activity of the racemic mixture and exhibited mitoprotective properties superior to those of the known macrocyclic cyclophilin inhibitors cyclosporin A and alisporivir. C105SR was more potent than C110SR in inhibiting mPTP opening and prevented cell death in a model of hypoxia/reoxygenation. Finally, C105SR substantially protected against hepatic IRI in vivo by reducing hepatocyte necrosis and apoptosis. Conclusions: We identified a novel cyclophilin inhibitor with strong mitoprotective properties both in vitro and in vivo that represents a promising candidate for cellular protection in hepatic IRI. Impact and Implications: Hepatic ischaemia-reperfusion injury (IRI) is one of the main causes of morbidity and mortality during or after liver surgery. However, no effective therapies are available to prevent or treat this devastating syndrome. An attractive strategy to prevent hepatic IRI aims at reducing cell death by targeting mitochondrial permeability transition pore opening, a phenomenon regulated by cyclophilin D. Here, we identified a new small-molecule cyclophilin inhibitor, and demonstrated the enhanced mitoprotective and hepatoprotective properties of one of its diastereoisomers both in vitro and in vivo, making it an attractive lead compound for subsequent clinical development.

Neutrophil accumulation within tissues: A damage x healing dichotomy.

The abundance of neutrophils in human circulation, their fast mobilization from blood to tissues, along with their alleged short life-span led to the image of neutrophils as a homogeneous cell type designed to fight infections and die in the process. Additionally, their granule content and capacity to produce molecules with considerable cytotoxic potential, lead to the general belief that neutrophil activation inexorably results in side effect of extensive tissue injury. Neutrophil activation in fact causes tissue injury as an adverse effect, but it seems that this is restricted to particular pathological situations and more of an "exception to the rule". Here we review evidences arising especially from intravital microscopy studies that demonstrate neutrophils as cells endowed with sophisticated mechanisms and able to engage in complex interactions as to minimize damage and optimize their effector functions. Moreover, neutrophil infiltration may even contribute to tissue healing and repair which may altogether demand a reexamination of current anti-inflammatory therapies that have neutrophil migration and activation as a target.

Selenoproteins Protect Against Avian Liver Necrosis by Metabolizing Peroxides and Regulating Receptor Interacting Serine Threonine Kinase 1/Receptor Interacting Serine Threonine Kinase 3/Mixed Lineage Kinase Domain-Like and Mitogen-Activated Protein Kinase Signaling.

Liver necroptosis of chicks is induced by selenium (Se)/vitamin E (VE) deficiencies and may be associated with oxidative cell damage. To reveal the underlying mechanisms of liver necrosis, a pool of the corn-soy basal diet (10 µg Se/kg; no VE added), a basal diet plus all-rac-α-tocopheryl acetate (50 mg/kg), Se (sodium selenite at 0.3 mg/kg), or both of these nutrients were provided to day-old broiler chicks (n = 40/group) for 6 weeks. High incidences of liver necrosis (30%) of chicks were induced by -SE-VE, starting at day 16. The Se concentration in liver and glutathione peroxidase (GPX) activity were decreased (P < 0.05) by dietary Se deficiency. Meanwhile, Se deficiency elevated malondialdehyde content and decreased superoxide dismutase (SOD) activity in the liver at weeks 2 and 4. Chicks fed with the two Se-deficient diets showed lower (P < 0.05) hepatic mRNA expression of Gpx1, Gpx3, Gpx4, Selenof, Selenoh, Selenok, Selenom, Selenon, Selenoo, Selenop, Selenot, Selenou, Selenow, and Dio1 than those fed with the two Se-supplemented diets. Dietary Se deficiency had elevated (P < 0.05) the expression of SELENOP, but decreased the downregulation (P < 0.05) of GPX1, GPX4, SELENON, and SELENOW in the liver of chicks at two time points. Meanwhile, dietary Se deficiency upregulated (P < 0.05) the abundance of hepatic proteins of p38 mitogen-activated protein kinase, phospho-p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, phospho-c-Jun N-terminal kinase, extracellular signal-regulated kinase, phospho-mitogen-activated protein kinase, receptor-interacting serine-threonine kinase 1 (RIPK1), receptor-interacting serine-threonine kinase 3 (RIPK3), and mixed lineage kinase domain-like (MLKL) at two time points. In conclusion, our data confirmed the differential regulation of dietary Se deficiency on several key selenoproteins, the RIPK1/RIPK3/MLKL, and mitogen-activated protein kinase signaling pathway in chicks and identified new molecular clues for understanding the etiology of nutritional liver necrosis.

The Effect of Different Doses of Mesobuthus eupeus (Scorpionida: Buthidae) Scorpion Venom on the Production of Liver Necrosis in Nmri Mice.

BACKGROUND: Scorpion venom has a variety of different components considerably. Some of these compounds are proteins such as Phospholipase A2 which is one of the most important. Use of scorpion venom for the treatment of any disease requires an initial study to determine the therapeutic dose or safe dose. Therefore, due to the necessity of studying scorpion venom, it is of special importance to study the effects of its dose response in animal tissues. METHODS: To determine the inflammatory effects of scorpion's venom (Mesobuthus eupeus), 50 Nmri mice with an average weight of 24±7g were selected for investigation in two experiments. In first-round 25 of them were divided into 5 groups and were exposed to different doses of venom injection paralleling the control group. Single-injection of various doses on 25 mice was performed and results were compared. RESULTS: There was a significant differences between the test and control groups (in most groups). Liver necrosis was one of the important symptoms in this study, the severity of which was measured and statistically analyzed. CONCLUSION: It was determined that 0.05ppm is a safe dose and sub-lethal doses can use for the investigation of therapeutic effects of venom on cancer, diabetes, dermatitis, and so on.

Acute liver failure and HELLP syndrome: A clinical case and literature review.

BACKGROUND: HELLP syndrome is a pregnancy-related liver disease associated with increased maternal and foetal mortality. In rare cases, it can lead to the development of a subcapsular hepatic haematoma as well as its rupture. This rupture is life-threatening if not urgently treated. METHOD: We describe a clinical case of HELLP syndrome involving a ruptured subcapsular liver haematoma and contextualise this with a literature overview. CLINICAL CASE: A 39-year-old woman of 40 weeks' gestation presented to her local Emergency Department with symptoms and serology classically associated with HELLP syndrome. However, she clinically deteriorated and developed a ruptured subcapsular haematoma. She underwent an emergency Caesarean section at her initial hospital. Upon clinical stabilisation, she was transferred to our transplant unit for an urgent liver transplant. CONCLUSION: LT is a life-saving procedure for patients with acute liver failure secondary to HELLP syndrome. These patients should be immediately referred to a high-volume transplant centre.

Exposure to Maternal Immune Activation Causes Congenital Unfolded Protein Response Defects and Increases the Susceptibility to Postnatal Inflammatory Stimulation in Offspring.

BACKGROUND: A number of childhood diseases have been identified, such as severe infection or autoinflammatory disease, in which immune overreaction against inflammation is a possible underlying mechanism. Previous reports have demonstrated that fetal cells exposed to maternal immune activation (MIA) induced by polyriboinosinic-polyribocytidylic acid [poly(I:C)] exhibited hypersensitivity to inflammation in vitro. However, the details of this mechanism remain unclear. Therefore, this study aimed to reveal the reaction to inflammation in offspring exposed to MIA in the prenatal period, as well as its molecular mechanism, using a viral infection mouse model. MATERIALS AND METHODS: Pregnant mice at 12.5, 14.5, and 16.5 days post coitum were injected intraperitoneally with poly(I:C) 20 mg/kg body weight (BW) or saline. Offspring aged 3-4 weeks received the second injection of 20 mg/kg BW or 4 mg/kg BW poly(I:C) or saline. Serum and tissues were collected at 2, 24, 48, and 72 h after the postnatal injection. The cytokine profile, histopathology of organs, and unfolded protein response (UPR) in offspring were examined. RESULTS: The serum levels of interleukin (IL)-6, IL-17, and interferon-γ were significantly higher in the MIA group, and acute liver necrosis was detected. Moreover, failure in UPR was observed in the MIA group compared with that in the control group. CONCLUSION: Overall, MIA exposure in utero caused failure in UPR as well as immune overreaction to the second attack of inflammation in offspring. Our results suggested that prenatal exposure to MIA might contribute to the congenital inflammatory constitution after birth.

Photodynamic and Sonodynamic Therapy with Protoporphyrin IX: In Vitro and In Vivo Studies.

Sono-photodynamic therapy is a promising anticancer technique based on the combination of sonodynamic and photodynamic therapy to improve the cancer treatment effectiveness. This study was aimed at analyzing the effects of the sono-photodynamic (SPD) activity on protoporphyrin IX (PpIX) solution and PpIX-loaded rat liver. In vitro, PpIX 5 µM solutions were irradiated with light (635 nm, 30-50 mW/cm2), ultrasound (1 MHz, 1-2 W/cm2) and both. The PpIX absorption spectra recorded over exposure time revealed that the PpIX decay rate induced by SPD activity (combined irradiation) was approximately the sum of those induced by photodynamic and sonodynamic activity. In vivo, rats were intraperitoneally injected with 5-aminolevulinic acid at the dose of 500 mg/kg weight. After 3 h of injection, the PpIX-loaded livers were irradiated with light (635 nm, 180 ± 9 J/cm2), ultrasound (1.0 MHz, 770 ± 40 J/cm2) and both using a single probe capable of illuminating and sonicating the liver simultaneously. After 30 h, the liver damage induced by each protocol was analyzed histologically. It was found that a greater necrosis depth was induced by the SPD activity. These results suggest that the SPD activity could improve the PpIX decay rate and have greater scope than photodynamic or sonodynamic activity. Further studies should be performed to gain a better understanding of this protocol.

Liver abscess with necrosis in post COVID-19: A case report.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is an acute respiratory tract infection caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2). Recent evidences mentioned the possibility of COVID-19 as a systemic infectious and inflammatory disease. Signs and symptoms of liver and gastrointestinal system are often found in post-acute COVID-19 patients. However, there are only few data found about liver abscess and necrosis in post COVID-19 patients. CASE PRESENTATION: A 49-year-old man admitted to the hospital with dyspnea, nausea, loss of appetite and epigastric pain, post confirmed SARS CoV-2 severe pneumonia 1 month ago in ICU with noninvasive ventilator (NIV), enoxaparin, tocilizumab, azithromycin, levofloxacin, hydroxychloroquine, and no preexisting liver condition. Swab PCR result was negative. The result of abdominal computed tomography (CT) scan with contrast was liver abscess formation with hemorrhages measuring about 16 × 12 × 11 cm & 10 × 9x9 cm occupying most of the right lobe liver. The patient underwent exploratory laparotomy, there were multiple liver abscesses in segment 8 with parenchymal liver necrosis and abscesses in segment 7 of liver. Necrosectomy and liver abscess drainage was performed. CLINICAL DISCUSSION: Pathophysiology of liver damage in post COVID-19 are direct cytotoxicity of SARS-CoV2, immune-mediated due to severe systemic inflammatory response syndrome (SIRS) in COVID-19, hypoxemia, vascular changes due to coagulopathy, endothelitis or congestion from right heart failure, and drug-induced liver injury (DILI). CONCLUSION: The possible pathophysiology of liver abscess and necrosis in post COVID-19 should be considered in monitoring and management for both COVID-19 patients and post COVID-19 patients.

Liver necrosis following cholecystectomy in sickle cell disease.

Postoperative vaso-occlusive disease may be a life-threatening condition in patients affected by sickle cell disease, necessitating sometimes liver transplantation. After laparoscopic cholecystectomy, liver necrosis is usually secondary to intraoperative vascular injury. In this patient, the vaso-occlusive crisis mimicked a vascular injury with segmental postoperative necrosis.

Prolonged neutrophil survival at necrotic sites is a fundamental feature for tissue recovery and resolution of hepatic inflammation.

Neutrophils were classically described as powerful effectors of acute inflammation, and their main purpose was assumed to be restricted to pathogen killing through production of oxidants. As consequence, neutrophils also may lead to significant collateral damage to the healthy tissues, and after performing these tasks, these leukocytes are supposed to die within tissues. However, there is a growing body of evidence showing that neutrophils also play a pivotal role in the resolution phases of inflammation, because they can modulate tissue environment due to secretion of different kind of cytokines. Drug-induced liver injury (DILI) is a worldwide concern being one of the most prevalent causes of liver transplantation, and is well established that there is an intense neutrophil recruitment into necrotic liver during DILI. However, information if such abundant granulocyte infiltration is also linked to the tissue repairing phase of hepatic injury is still largely elusive. Here, we investigated the dynamics of neutrophil trafficking within blood, bone marrow, and liver during hepatic inflammation, and how changes in their gene expression profile could drive the resolution events during acetaminophen (APAP)-induced liver injury. We found that neutrophils remained viable during longer periods following liver damage, because they avidly patrolled necrotic areas and up-regulated pro-resolutive genes, including Tgfb, Il1r2, and Fpr2. Adoptive transference of "resolutive neutrophils" harvested from livers at 72 h after injury to mice at the initial phases of injury (6 h after APAP) significantly rescued organ injury. Thus, we provide novel insights on the role of neutrophils not only in the injury amplification, but also in the resolution phases of inflammation.