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To achieve multifunctional properties using nanocomposites, selectively locating nanofillers in specific areas by tailoring a mixture of two immiscible polymers has been widely investigated. Forming a phase-separated structure from entirely miscible molecules is rarely reported, and the related mechanisms to govern the formation of assemblies from molecules have not been fully resolved. In this work, a novel method and the underlying mechanism to fabricate self-assembling, bicontinuous, biphasic structures with localized domains made up of amine-functionalized graphene nanoplatelets are presented, involving the tailoring of compositions in a liquid processable multicomponent epoxy blend. Kinetics studies were carried out to investigate the differences in reactivity of various epoxy-hardener pairs. Molecular dynamics simulations and in situ optical photothermal infrared spectroscopy measurements revealed the trajectories of different components during the early stages of polymerization, supporting the migration (phase behavior) of each component during the curing process. Confirmed by the phase structure and the correlated chemical maps down to the submicrometer level, it is believed that the bicontinuous phase separation is driven by the change of the miscibility between various building blocks forming during polymerization, leading to the formation of nanofiller domains. The proposed morphology evolution mechanism is based on combining solubility parameter calculations with kinetics studies, and preliminary experiments are performed to validate the applicability of the mechanism of selectively locating nanofillers in the phase-separated structure. This provides a simple yet sophisticated engineering model and a roadmap to a mechanism for fabricating phase-separated structures with nanofiller domains in nanocomposite films.
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Our knowledge of the severity and reoffending is limited for mentally disordered offenders, and studies generally evaluate without separation between different diagnostic groups. It was aimed to determine the general profile of mentally disordered offenders who are inpatients in a high secure psychiatry unit from Turkiye and to evaluate the factors associated with violence profiles among different diagnostic groups. According to the results the schizophrenia patients committed the most severe crimes, and intellectual disability patients had some different features from schizophrenia and bipolar disorder patients. History of substance misuse in the intellectual disability group (p = 0,045) and comorbid antisocial personality disorder in the bipolar disorder group (p = 0,015) were associated with increased crime severity. Substance misuse history, history of substance use during the crime, and the existence of comorbid antisocial personality disorder were associated with increased offenses in each of the three diagnosis groups. Living alone (p = 0,004) and having a suicide history (p= 0,052) were associated with the high number of offenses in the schizophrenia group. This study is the first study that compares three diagnostic groups to involve a large patient group. We believe that clinicians must evaluate these parameters for the violence risk assessment of patients.
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Violência , Humanos , Masculino , Adulto , Violência/psicologia , Transtornos Mentais/psicologia , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Criminosos/psicologia , Esquizofrenia , Transtorno da Personalidade Antissocial/psicologia , Transtorno da Personalidade Antissocial/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto Jovem , Transtorno Bipolar/psicologia , Deficiência Intelectual/psicologia , ComorbidadeRESUMO
BACKGROUND: In patients undergoing liver transplantation for metabolic diseases, removing the patient's liver for transplantation to another recipient is called "domino liver transplantation." The extracted liver can be divided and transplanted into 2 recipients, which is called domino split-liver transplantation in the literature. However, in our study, the domino liver was obtained from a pediatric patient. METHODS: A patient with maple syrup urine disease (MSUD) underwent a living donor liver transplant, and the explanted liver was divided in situ into right and left lobes and transplanted to 2 separate patients. Demographic data, surgical techniques, postoperative period, and patient follow-ups were evaluated. RESULTS: The father's left lobe liver graft was transplanted into a 12-year-old boy with MSUD. The removed liver was divided in situ into right and left lobes. The left lobe was transplanted to a 14-year-old male patient, whereas the right lobe was transplanted to a 67-year-old male patient. The donor and the first recipient were discharged on postoperative days 5 and 22. The second pediatric patient who underwent domino split-left lobe transplantation was discharged on postoperative day 23. The adult patient who underwent domino split-right lobe transplantation died on postoperative day 12 owing to massive esophageal variceal bleeding. CONCLUSION: Patients who underwent liver transplantation due to MSUD are among the best donor choices for domino liver transplantation. If the extracted liver has a sufficient volume and anatomic features for a split, it can be used in "selected cases."
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Varizes Esofágicas e Gástricas , Transplante de Fígado , Doença da Urina de Xarope de Bordo , Masculino , Adulto , Humanos , Criança , Adolescente , Idoso , Transplante de Fígado/métodos , Doadores Vivos , Hemorragia Gastrointestinal , Doença da Urina de Xarope de Bordo/cirurgiaRESUMO
OBJECTIVES: Chylothorax without chylous ascites after liver transplant is rare. We present 2 cases of isolated chylothorax after liver transplant and a literature review. MATERIALS AND METHODS: We compiled a literature review of chylothorax cases after abdominal surgery and analyzed the cases related to liver transplant. The demographic information, follow-up results, and treatment details of our 2 cases of chylothorax after living-donor pediatric livertransplant were discussed. RESULTS: An 8-month-old child and a 15-month-old child with cholestatic liver disease and urea cycle defect, respectively, underwent living-donor left lateral segment liver transplant. Patients who presented with chylothorax after discharge were treated conservatively. CONCLUSIONS: Isolated chylothorax is rare complication after abdominal surgery, which is mostly possible to treat with conservative methods. Interventional procedures and a surgical approach should only be performed in resistant cases when conservative treatment has failed.
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Quilotórax , Ascite Quilosa , Transplante de Fígado , Humanos , Criança , Lactente , Quilotórax/diagnóstico por imagem , Quilotórax/etiologia , Quilotórax/terapia , Transplante de Fígado/efeitos adversos , Doadores Vivos , Ascite Quilosa/etiologiaRESUMO
The irreversibility of anion intercalation-deintercalation is a fundamental issue in determining the cycling stability of a dual-ion battery (DIB). In this work, we demonstrate that using a partially fluorinated carbonate solvent can drive a beneficial fluorinated secondary interphase layer formation. Such layer facilitates reversible anion (de-)intercalation processes by impeding solvent molecule co-intercalation and the associated graphite exfoliation. The enhanced reversibility of anion transport contributes to the overall cycling stability for a Zn-graphite DIB-a high Coulombic efficiency of 98.5 % after 800â cycles, with an attractive discharge capacity of 156â mAh g-1 and a mid-point discharge voltage of ≈1.7â V (at 0.1â A g-1 ). In addition, the formed fluorinated secondary interphase suppresses the self-discharge behavior, preserving 29â times of the capacity retention rate compared to the battery with a commonly used carbonate solvent, after standing for 24â hours. This work provides a simple and effective strategy for addressing the critical challenges in graphite-based DIBs and contributes to fundamental understanding to help accelerate their practical application.
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Ensuring optimal arterial flow in solid organ transplantation is very important. Insufficient flow causes important problems such as bile duct problems, intrahepatic abscess formation, and organ loss. Arterial intimal dissection is an important factor that negatively affects organ blood flow. In this study, hepatic artery dissections that we detected in patients who underwent living donor liver transplantation in our clinic were defined, and the microvascular intima-adventitial fixation technique, which can be considered a new approach, was described.
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Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Artéria Hepática/cirurgia , Doadores Vivos , Espessura Intima-Media Carotídea , FígadoRESUMO
The safety concern arising from flammable liquid electrolytes used in batteries and supercapacitors drives technological advances in solid polymer electrolytes (SPEs) in which flammable organic solvents are absent. However, there is always a trade-off between the ionic conductivity and mechanical properties of SPEs due to the lack of interaction between the ionic liquid and polymer resin. The inadequate understanding of SPEs also limits their future exploitation and applications. Herein, we provide a complete approach to develop a new SPE, consisting of a cation (monomer), anion and hardener from ions-monomers using molecular dynamics (MD) simulations. The results show that the strong solid-liquid interactions between the SPE and graphene electrode lead to a very small gap of â¼5.5 Å between the components of SPE and electrode, resulting in a structured solid-to-liquid interface, which can potentially improve energy storage performance. The results also indicated the critical role of the mobility of free-standing anions in the SPE network to achieve high ionic conductivity for applications requiring fast charge/discharge. In addition, the formations of hardener-depleted regions and cation-anion-poor/rich regions near the uncharged/charged electrode surfaces were observed at the molecular level, providing insights for rationally designing the SPEs to overcome the boundaries for further breakthroughs in energy storage technology.
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Widely applicable, modified Green-Kubo expressions for the local diffusion coefficient (Dl) are obtained using linear response theory. In contrast to past definitions in use, these expressions are statistical mechanical results. Molecular simulations of systems with anisotropic diffusion and an inhomogeneous density profile confirm the validity of the results. Diffusion coefficients determined from different expressions in terms of currents and velocity correlations agree in the limit of large systems. Furthermore, they apply to arbitrarily small local regions, making them readily applicable to nanoscale and inhomogeneous systems where knowledge of Dl is important.
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Física , Anisotropia , DifusãoRESUMO
OBJECTIVE: Pulmonary complications are common in patients with liver cirrhosis. Devolopment of pulmonary hypertension (PH) is associated with a poor prognosis in these patients. Pulmonary arterial stiffness (PAS) is considered an early sign of pulmonary vascular remodeling. The aim of this study is to investigate PAS and compare it with right ventricular (RV) functions in patients with cirrhosis who are scheduled for liver transplantation. METHODS: The study included 52 cirrhosis patients (mean age 51.01 ± 12.18 years, male gender 76.9%) who were prepared for liver transplantation and 59 age and sex matched (mean age 51.28 ± 13.63 years, male gender 62.7%) healthy individuals. Patients with left ventricular ejection fraction (LVEF) less than 55%, ischemic heart disease, more than mild valvular heart disease, chronic pulmonary disease, congenital heart disease, rheumatic disease, moderate to high echocardiographic PH probability, rhythm or conduction disorders on electrocardiography were excluded from the study. In addition to conventional echocardiographic parameters, PAS value, pulmonary vascular resistance (PVR) and RV ejection efficiency was calculated by the related formulas with transthoracic echocardiography (TTE). RESULTS: Demographic characteristics and cardiovascular risk factors of the groups were similar. PAS, PVR, and sPAP values were found to be significantly higher in the patient group (20.52 ± 6.52 and 13.73 ± 2.05; 1.43 ± 0.15 and 1.27 ± 0.14; 27.69 ± 3.91 and 23.37 ± 3.81 p < 0.001, respectively). RV FAC and RV Ee were significantly lower and RV MPI was significantly higher in the patient group (45.31 ± 3.85 and 49.66 ± 3.62, p < 0.001; 1.69 ± 0.35 and 1.85 ± 0.23, p = 0.005; 0.39 ± 0.07 and 0.33 ± 0.09, p = 0.001, respectively). PAS was significantly correlated with RV FAC and MPI (r = -0.423, p < 0.001; r = 0.301, p = 0.001, respectively). CONCLUSIONS: Increased PAS in cirrhosis patients may be associated with early pulmonary vascular involvement. Evaluation of RV functions is important to determine the prognosis in these patients. FAC, MPI, and RV Ee measurements instead of TAPSE or RV S' may be more useful in demonstrating subclinical dysfunction. The correlation of PAS with RV FAC and MPI may indicate that RV subclinical dysfunction is associated with early pulmonary vascular remodeling in patients with liver cirrhosis.
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Hipertensão Pulmonar , Cirrose Hepática , Transplante de Fígado , Rigidez Vascular , Adulto , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/diagnóstico por imagem , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Remodelação Vascular , Disfunção Ventricular Direita/complicações , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Esquerda , Função Ventricular DireitaRESUMO
Poly(phosphazenes)(PZ) are versatile polymers due to their tunable properties that can be tailored for specific applications. Despite extensive experimental research, not all properties are tested, and the list of PZs studied via molecular simulations is limited. Further, a general procedure to generate and test PZ systems is lacking. We present an in situ polymerization procedure developed to make, test, and tune the thermo-mechanical properties of four PZs-poly(dichlorophosphazene)(PZ-DC), poly[bis(2,2,2-trifluoroethoxy)]phosphazene (PZ-TFE), poly(2,2,2-trifluoroethoxy-5,6-diazidohexanoxy) phosphazene (PZ-Azido), and poly(2,2,2-trifluoroethoxy-5,6-dinitratohexanoxy)phosphazene (PZ-Nitrato) via molecular dynamics simulations. The predicted thermo-mechanical properties (i.e., density and glass transition temperature) agreed with experimental values when a direct comparison of PZ systems was possible. This demonstrates the reproducibility and reliability of our procedure which will help understand the behaviour of PZs at the molecular scale.
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There has been increasing interest in the emerging ionic thermoelectric materials with huge ionic thermopower. However, it's challenging to selectively tune the thermopower of all-solid-state polymer materials because the transportation of ions in all-solid-state polymers is much more complex than those of liquid-dominated gels. Herein, this work provides all-solid-state polymer materials with a wide tunable thermopower range (+20~-6 mV K-1), which is different from previously reported gels. Moreover, the mechanism of p-n conversion in all-solid-state ionic thermoelectric polymer material at the atomic scale was presented based on the analysis of Eastman entropy changes by molecular dynamics simulation, which provides a general strategy for tuning ionic thermopower and is beneficial to understand the fundamental mechanism of the p-n conversion. Furthermore, a self-powered ionic thermoelectric thermal sensor fabricated by the developed p- and n-type polymers demonstrated high sensitivity and durability, extending the application of ionic thermoelectric materials.
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OBJECTIVE: Viral infections are known to be a risk factor for neonatal hearing loss. COVID-19 infection has been reported to affect hearing test results in one small sample sized study. We aimed to investigate the incidence the risk of neonatal hearing loss in infants of mothers who had COVID-19 infection during pregnancy, regarding their trimesters, by evaluating the neonatal hearing screening results. DESIGN: In this retrospective case-control study, neonatal hearing test results of 458 women with a history of COVID-19 infection in pregnancy were compared with 339 women who gave birth before the pandemic. Data of pregnant women who attended the COVID-19 outpatient clinic of the emergency service of a tertiary pandemic hospital and who had confirmed infection with a reverse transcriptase-polymerase chain reaction (RT-PCR) test were determined from the hospital's records and their neonatal hearing screening results were analyzed from the national database. Neonates born before <34 weeks, and with reported risk factors in the database such as congenital anomaly or known TORCH infection during pregnancy were excluded. The screening tests, Automated Auditory Brainstem Response or Transient Evoked Otoacoustic Emission (TEOAE), were used for screening, and patients who failed the first screening were reevaluated at least 2 weeks apart with a second screening. RESULTS: The incidence of failed second screening was 1.3% in the COVID-19 group and 2.9% in controls, and no significant difference was observed between the two groups according to the final screening results on the second test. Among the 458 mothers, 8 were infected in first trimester, 126 in second trimester, 127 in third trimester but did not deliver within 15 days after infection and 197 were positive at birth. Six neonates in the infected group failed the second screening (3 [2.4%] in the second trimester, 1 [0.8%] third trimester, and 2 [1.0%] positive at birth). CONCLUSIONS: COVID-19 infection during pregnancy was not found to be a risk factor for hearing loss, according to the newborn hearing screening results.
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COVID-19 , Estudos de Casos e Controles , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Testes Auditivos , Humanos , Lactente , Recém-Nascido , Mães , Triagem Neonatal , Emissões Otoacústicas Espontâneas , Gravidez , Estudos Retrospectivos , SARS-CoV-2RESUMO
Balance between self-association of structural units and self-repulsion from crowding-induced steric hindrance accounts for the supramolecular assembly of the amphiphilic entities to form ordered structures, and solvation provides a toolbox to conveniently modulate the assemblies through differential interactions to various structural units. Here we report solvation-modulated supramolecular chiral assembly in aqueous solutions of amphiphilic dendronized tetraphenylethylenes (TPEs) with three-folded dendritic oligoethylene glycols (OEGs) through dipeptide Ala-Gly linkage. These dendronized amphiphiles can form supramolecular spheres with enhanced supramolecular chirality, which is tunable and dependent on solvation. These nanosized spherical aggregates exhibit thermoresponsive behavior, and their cloud point temperatures are dependent on mixed solvent of water and THF. The phase transition temperatures increase with water fractions due to water-driven shifting of OEG moieties from interiors of the aggregates to their peripheries. Furthermore, the thermally induced dehydration and collapse of OEG moieties mediate the reversible aggregation and deaggregation between the spheres, imparting tunable aggregation-induced fluorescent emission (AIE) and supramolecular chirality. Both experimental results and molecular dynamic simulations have highlighted that reversible chirality transformations of the amphiphilic dendronized assemblies mediated by solvation through change solvent quality or thermally dehydration are dependent on the balance between interactions of OEG dendrons with TPE moieties and with the solvent molecules.
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Corantes , Solventes , TemperaturaRESUMO
Transformation of supramolecular chiral assemblies into covalent polymers integrates characteristics of supramolecular chemistry together with covalent entities, leading to fabrication of covalent chiral materials through versatile supramolecular chiral assemblies. Here, we report supramolecular assembly of an amphiphilic dendronized 10,12-pentacosadiynoic amide (PCDA) in aqueous solutions to form twisted ribbons, which were transferred into covalent dendronized polydiacetylenes (PDAs) via photopolymerization. These supramolecular dendronized PCDA and the corresponding covalent dendronized PDAs showed unprecedent thermoresponsive properties. The thermally-induced dehydration and aggregations tuned reversibly their chiralities, which can be visually inspected through colour changes.
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Liver transplantation surgery due to cirrhosis in patients with hemophilia is rare and there are limited cases in the literature. We present a case of a patient with hemophilia A who underwent 2 consecutive surgeries owing to coronary artery disease and cryptogenic cirrhosis with hepatocellular carcinoma. After these surgeries, no bleeding or other complications were seen, and the factor VIII levels have not changed since liver transplantation in the follow-up.
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Hemofilia A , Neoplasias Hepáticas , Transplante de Fígado , Ponte de Artéria Coronária , Hemofilia A/complicações , Hemofilia A/diagnóstico , Humanos , Neoplasias Hepáticas/cirurgia , Doadores VivosRESUMO
Recently, a new generation of polymerised ionic liquids with high thermal stability and good mechanical performances has been designed through novel and versatile cycloaliphatic epoxy-functionalised ionic liquids (CEILs). From these first promising results and unexplored chemical structures in terms of final properties of the PILs, a computational approach based on molecular dynamics simulations has been developed to generate polymer models and predict the thermo-mechanical properties (e.g., glass transition temperature and Young's modulus) of experimentally investigated CEILs for producing multi-functional polymer materials. Here, a completely reproducible and reliable computational protocol is provided to design, test and tune poly(ionic liquids) based on epoxidised ionic liquid monomers for future multi-functional thermoset polymers.
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BACKGROUND: 25-hydroxy VD insufficiency is known in children undergoing LT but the serial post-transplant VD course and supplementation modalities in the peri-transplant period are lacking. We aimed to determine the pre-VD status and the post-transplant VD status course following VD supplementation and to elucidate its relationship with post-transplant outcome parameters such as infection and survival. METHODS: Pre- and post-VD levels were monitored in parallel with interventions to adjust VD levels in LT patients. VD status was categorized as circulating levels <30-21 ng/ml (insufficiency), 20-10 ng/ml (deficiency), and <10 ng/ml (severe deficiency). Patients received stoss (300000IU) VD3 within the pretransplant period if serum levels were <20 ng/ml. RESULTS: 135 transplanted children were included. The age at LT was 22 months (IQR: 8-60). The pretransplant median VD level was 14 ng/ml. Despite stoss dose, post-transplant median VD level was 1.8 ng/ml (day one), 4 ng/ml (week one), 19 ng/ml (month one), 33 ng/ml (month three), 38 ng/ml (months 6-12), and 40 ng/ml (month 24). After 6 months, VD status reached >30 ng/ml in 98% of patients. Only at pre-LT, higher infection rate (18.7%) in the severe VD deficiency group was observed compared to the VD deficiency group (2.9%, p = .04). Survival was not affected by serum VD levels. CONCLUSION: VD levels fell substantially after LT but are rectifiable by stoss dose, which was well tolerated. Only the infection rate was associated with the VD status.
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Transplante de Fígado , Complicações Pós-Operatórias/tratamento farmacológico , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/uso terapêutico , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
In this work, we investigate the effect of the cation structure on the structure and dynamics of the electrode-electrolyte interface using molecular dynamics simulations. A constant potential method is used to capture the behaviour of 1-ethyl-3-methylimidazolium bis (trifluoromethane)sulfonimide ([C2mim][NTf2]) and butyltrimethylammonium bis(trifluoromethane) sulfonimide ([N4,1,1,1][NTf2]) ionic liquids at varying potential differences applied across the supercapacitor. We find that the details of the structure in the electric double layer and the dynamics differ significantly, yet the charge profile and capacitance do not vary greatly. For the systems considered, charging results in the rearrangement and reorientation of ions within â¼1 nm of the electrode rather than the diffusion of ions to/from the bulk region. This occurs on timescales of O(10 ns) for the ionic liquids considered, and depends on the viscosity of the fluid.
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The conjugation of hydrophilic low-fouling polymers to therapeutic molecules and particles is an effective approach to improving their aqueous stability, solubility, and pharmacokinetics. Recent concerns over the immunogenicity of poly(ethylene glycol) has highlighted the importance of identifying alternative low fouling polymers. Now, a new class of synthetic water-soluble homo-fluoropolymers are reported with a sulfoxide side-chain structure. The incorporation of fluorine enables direct imaging of the homopolymer by 19 F MRI, negating the need for additional synthetic steps to attach an imaging moiety. These self-reporting fluoropolymers show outstanding imaging sensitivity and remarkable hydrophilicity, and as such are a new class of low-fouling polymer for bioconjugation and inâ vivo tracking.
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Polietilenoglicóis/síntese química , Sulfóxidos/química , Flúor/química , Halogenação , Interações Hidrofóbicas e Hidrofílicas , Imageamento por Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Polietilenoglicóis/química , Solubilidade , Água/químicaRESUMO
Posterior reversible encephalopathy syndrome (PRES) is a neuroradiologic syndrome. The etiology of PRES is still unclear. Some factors were described. We present a case of a pediatric patient with liver transplant who developed PRES following blood transfusion while receiving tacrolimus therapy. A 5½-year-old boy who underwent living donor liver transplantation, and PRES developed on the sixth day post transplant under tacrolimus treatment after 6 hours of red blood transfusion. PRES is a rare condition; it should be kept in mind about patients who have received organ transplants and develop sudden neurologic symptoms.