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1.
Cells ; 13(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38534373

RESUMO

Extended liver resection carries the risk of post-surgery liver failure involving thrombospondin-1-mediated aggravation of hepatic epithelial plasticity and function. Mesenchymal stromal cells (MSCs), by interfering with thrombospondin-1 (THBS1), counteract hepatic dysfunction, though the mechanisms involved remain unknown. Herein, two-thirds partial hepatectomy in mice increased hepatic THBS1, downstream transforming growth factor-ß3, and perturbation of liver tissue homeostasis. All these events were ameliorated by hepatic transfusion of human bone marrow-derived MSCs. Treatment attenuated platelet and macrophage recruitment to the liver, both major sources of THBS1. By mitigating THBS1, MSCs muted surgery-induced tissue deterioration and dysfunction, and thus supported post-hepatectomy regeneration. After liver surgery, patients displayed increased tissue THBS1, which is associated with functional impairment and may indicate a higher risk of post-surgery complications. Since liver dysfunction involving THBS1 improves with MSC treatment in various animal models, it seems feasible to also modulate THBS1 in humans to impede post-surgery acute liver failure.


Assuntos
Hepatopatias , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Hepatectomia , Regeneração Hepática/fisiologia , Trombospondinas
2.
J Toxicol Environ Health A ; 86(13): 421-433, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37203870

RESUMO

Tetrachlorvinphos (TCVP) is the pesticidal active ingredient in some collars for dogs and cats. The objective of this study was to provide a refined estimate of dermal penetration of TCVP in humans using in silico predictions as well as in vitro and in vivo data. The in vivo dermal absorption of TCVP was previously studied in the rat and shown to be saturable, ranging from 21.7% (10 µg/cm2) down to 3% (1000 µg/cm2) Subsequent in silico predictions were conducted for rats and humans to provide initial evaluations of species and dose-dependent differences in dermal absorption. A definitive comparison of TCVP systemic exposure in rat and human following dermal application was then conducted via a standard in vitro assay. TCVP dose levels of 10, 100, or 1000 µg/cm2 were applied to excised rat and human skin mounted in flow-through diffusion cells. The vehicle was 1% hydroxypropylmethylcellulose (HPMC) in water. An additional 5 µg/cm2 dose was applied to excised human skin only. The in vitro dermal absorption of TCVP was also assessed from artificial sebum at dose levels of 5, 10, or 100 µg/cm2 applied to human skin only. Utilizing the so-called triple pack approach with in vitro and in vivo rat data and in vitro human data, dermal absorption for TCVP was calculated for humans. In silico modeling indicated absorption of TCVP through human skin might be 3- to 4- fold lower than rat skin at all application levels, with a maximum dermal absorption of 9.6% at the lowest exposure of 10 µg/cm2, down to 0.1% at 1000 µg/cm2. Similar species differences were also found in the definitive in vitro absorption assays. Modeling overestimated TCVP human dermal absorption (9.6%) as compared to excised human skin results (1.7%) for the HPMC vehicle at the lowest exposure (10 µg/cm2), with better agreement at the higher exposures. Conversely, modeling accurately predicted rat dermal absorption (27.9%) as compared to in vivo rat results (21.7%) at the lowest exposure in HPMC, with diminished agreement at the higher exposures. As a first approximation, in silico estimates of dermal absorption are useful; however, these tend to be more variable than in vitro or in vivo measurements. TCVP dermal penetration measured in vitro was lower in 1% HPMC vehicle as compared to artificial sebum. For the 1% HPMC vehicle, in vitro rat dermal absorption was similar to data obtained for in vivo rats, giving confidence in the triple pack approach. In consideration of the triple pack approach, estimated human dermal absorption from 1% HPMC was ≤2%. Based upon excised human skin determinations directly, estimated human dermal absorption of TCVP from artificial sebum was ≤7%.


Assuntos
Doenças do Gato , Doenças do Cão , Humanos , Ratos , Animais , Cães , Gatos , Tetraclorvinfos/metabolismo , Doenças do Gato/metabolismo , Doenças do Cão/metabolismo , Pele/metabolismo , Absorção Cutânea
3.
Zentralbl Chir ; 148(2): 140-146, 2023 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-34763360

RESUMO

BACKGROUND: The standard treatment for acute cholecystitis is laparoscopic cholecystectomy. Alternative procedures are used for patients at high surgical risk. Percutaneous drainage is widely available. The alternative of transpapillary drainage of the gallbladder via the ductus cysticus has only limited prospects of success. With the widespread use of interventional endoscopic ultrasound and the development of new stent systems, endoscopic ultrasound gallbladder drainage has proven to be a safe and reliable procedure. MATERIAL AND METHOD: We retrospectively report on our experiences in 11 consecutive patients with endoscopic ultrasound gallbladder drainage in acute cholecystitis between December 2018 and January 2021. RESULTS: 11 patients with acute cholecystitis with a mean age of 84.5 years (70-95 years) are reported. All patients had severe general comorbidities or advanced abdominal tumours or a combination of these conditions. After interdisciplinary debate, the indication for interventional therapy was made. This was carried out in 9 cases by means of endosonographic drainage alone and in 2 cases by means of percutaneous and two-stage endosonographic drainage. Technical success was achieved in 10 cases (91%), clinical success in 9 cases (82%). In 2 cases there were procedural complications that led to the operation. CONCLUSION: In the case of high surgical risks, endosonographic drainage of the gall bladder is a safe and definitive therapy. This can be performed alone or in combination with percutaneous drainage. Endoscopic ultrasound drainage is superior to percutaneous drainage alone, due to its lower complication rates and lower rates of necessary follow-up interventions. Therefore, in cases of relatively high surgical risk, endoscopic ultrasound drainage of the gall bladder should be preferred to percutaneous drainage, especially when definitive therapy is required.


Assuntos
Colecistectomia Laparoscópica , Colecistite Aguda , Humanos , Idoso de 80 Anos ou mais , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/cirurgia , Estudos Retrospectivos , Colecistite Aguda/diagnóstico por imagem , Colecistite Aguda/cirurgia , Drenagem
4.
Xenobiotica ; 52(5): 498-510, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35822285

RESUMO

Metabolism data for MCPA in rat, dog and human shows a single oral dose is quantitatively and rapidly absorbed with evidence of non-linear kinetics at >100 mg/kg bw. The extent of metabolism is low and consistent between rat and human, with substantially higher metabolic conversion in dog. Parent accounts for 50%-67% dose in rat, ∼40% in human and 2%-27% in dog. No dog specific metabolite is apparent.In rat and human, MCPA and metabolites are rapidly eliminated in urine (65%-70% within 24 h) but in dog, excretion is via urine and faeces (20%-30% within 24 h), with renal excretion saturating between 5 and 100 mg/kg bw.The species difference in excretion is reflected in pharmacokinetics. Terminal half-life is similar in rat and human (15-17 h) but higher in dog (47 h). Modelling shows species differences in single dose kinetics profoundly affect systemic exposure following repeat dosing.The difference in renal excretion and systemic exposure of MCPA between dogs and rats has been attributed to species differences in active transporters (OAT1/OAT3). A new in vitro flux study in renal proximal tubules supports this hypothesis with net secretion in rat and human of a similar magnitude but significantly less in dog.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético , Herbicidas , Animais , Cães , Fezes , Humanos , Cinética , Ratos , Especificidade da Espécie
5.
Toxicol Appl Pharmacol ; 440: 115922, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35176293

RESUMO

Although external concentrations are more readily quantified and often used as the metric for regulating and mitigating exposures to environmental chemicals, the toxicological response to an environmental chemical is more directly related to its internal concentrations than the external concentration. The processes of absorption, distribution, metabolism, and excretion (ADME) determine the quantitative relationship between the external and internal concentrations, and these processes are often susceptible to saturation at high concentrations, which can lead to nonlinear changes in internal concentrations that deviate from proportionality. Using generic physiologically-based pharmacokinetic (PBPK) models, we explored how saturable absorption or clearance influence the shape of the internal to external concentration (IEC) relationship. We used the models for hypothetical chemicals to show how differences in kinetic parameters can impact the shape of an IEC relationship; and models for styrene and caffeine to explore how exposure route, frequency, and duration impact the IEC relationships in rat and human exposures. We also analyzed available plasma concentration data for 2,4-dichlorophenoxyacetic acid to demonstrate how a PBPK modeling approach can be an alternative to common statistical methods for analyzing dose proportionality. A PBPK modeling approach can be a valuable tool used in the early stages of a chemical safety assessment program to optimize the design of longer-term animal toxicity studies or to interpret study results.


Assuntos
Modelos Biológicos , Animais , Ratos
6.
Regul Toxicol Pharmacol ; 129: 105117, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35017021

RESUMO

Methylenediphenyl diisocyanate (MDI) substances used polyurethane production can range from their simplest monomeric forms (e.g., 4,4'-MDI) to mixtures of the monomers with various homologues, homopolymer, and prepolymer derivatives. The relative dermal or inhalation absorption of 39 constituents of these substances in human were predicted using the GastroPlus® program. Predicted dermal uptake and absorption of the three MDI monomers from an acetone vehicle was 84-86% and 1.4-1.5%, respectively, with lower uptake and absorption predicted for the higher MW analogs. Lower absorption was predicted from exposures in a more lipophilic vehicle (1-octanol). Modeled inhalation exposures afforded the highest pulmonary absorption for the MDI monomers (38-54%), with 3-27% for the MW range of 381-751, and <0.1% for the remaining, higher MW derivatives. Predicted oral absorption, representing mucociliary transport, ranged from 5 to 10% for the MDI monomers, 10-25% for constituents of MW 381-751, and ≤3% for constituents with MW > 900. These in silico evaluations should be useful in category-based, worst-case, Read-Across assessments for MDI monomers and modified MDI substances for potential systemic effects. Predictions of appreciable mucociliary transport may also be useful to address data gaps in oral toxicity testing for this category of compounds.


Assuntos
Exposição por Inalação/análise , Isocianatos/química , Isocianatos/farmacocinética , Pulmão/metabolismo , Absorção Cutânea/fisiologia , Administração por Inalação , Excipientes/química , Modelos Biológicos , Peso Molecular
7.
NPJ Regen Med ; 6(1): 84, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34862411

RESUMO

Post-surgery liver failure is a serious complication for patients after extended partial hepatectomies (ePHx). Previously, we demonstrated in the pig model that transplantation of mesenchymal stromal cells (MSC) improved circulatory maintenance and supported multi-organ functions after 70% liver resection. Mechanisms behind the beneficial MSC effects remained unknown. Here we performed 70% liver resection in pigs with and without MSC treatment, and animals were monitored for 24 h post surgery. Gene expression profiles were determined in the lung and liver. Bioinformatics analysis predicted organ-independent MSC targets, importantly a role for thrombospondin-1 linked to transforming growth factor-ß (TGF-ß) and downstream signaling towards providing epithelial plasticity and epithelial-mesenchymal transition (EMT). This prediction was supported histologically and mechanistically, the latter with primary hepatocyte cell cultures. MSC attenuated the surgery-induced increase of tissue damage, of thrombospondin-1 and TGF-ß, as well as of epithelial plasticity in both the liver and lung. This suggests that MSC ameliorated surgery-induced hepatocellular stress and EMT, thus supporting epithelial integrity and facilitating regeneration. MSC-derived soluble factor(s) did not directly interfere with intracellular TGF-ß signaling, but inhibited thrombospondin-1 secretion from thrombocytes and non-parenchymal liver cells, therewith obviously reducing the availability of active TGF-ß.

8.
Healthcare (Basel) ; 9(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207501

RESUMO

Laparoscopic liver resection (LLR) is an increasingly relevant treatment option for patients with resectable hepatocellular carcinoma (HCC). Orthotopic liver transplantation (OLT) has been considered optimal treatment for HCC in cirrhosis, but is challenged by rising organ scarcity. While health-related quality of life (HRQoL) and mental health are well-documented after OLT, little is known about HRQoL in HCC patients after LLR. We identified all HCC patients who underwent LLR at our hospital between 2014 and 2018. HRQoL and mental health were assessed using the Short Form 36 and the Hospital Anxiety and Depression Scale, respectively. Outcomes were compared to a historic cohort of HCC patients after OLT. Ninety-eight patients received LLR for HCC. Postoperative morbidity was 25% with 17% minor complications. LLR patients showed similar overall HRQoL and mental health to OLT recipients, except for lower General Health (p = 0.029) and higher anxiety scores (p = 0.010). We conclude that LLR can be safely performed in patients with HCC, with or without liver cirrhosis. The postoperative HRQoL and mental health are comparable to that of OLT recipients in most aspects. LLR should thus always be considered an alternative to OLT, especially in times of organ shortage.

10.
World J Surg Oncol ; 18(1): 158, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32635931

RESUMO

BACKGROUND: The Milan criteria (MC) are widely used for the indication of liver transplantation (LTx) in hepatocellular carcinoma (HCC). Good long-term results have also been reported following LTx for patients exceeding the MC. In this article, we compare the overall and recurrence-free survival of our patients fulfilling and exceeding the MC according to the post-transplant histopathological results. PATIENTS AND METHODS: Data from 120 patients with HCC (22 females and 98 males) were analyzed. The median patient age was 61 years (Q1, Q3 54.7, 65.4), and the median MELD score was 11 (Q1, Q3 8, 15). The median follow-up period was 53 months (Q1, Q3 16.6, 78). Patients were categorized into established criteria (MC, up-to-seven (UTS), Asan criteria, AFP score), and the outcome of the individual groups was compared. RESULTS: Seventy-four of 120 patients fulfilled the MC, 86 patients met the UTS criteria, 85 patients fulfilled the Asan criteria, and 79 patients had an AFP score less than or equal to 2. The 1- and 5-year survival rates of all patients were 76.7% and 55.6%, respectively. In total, 14.2% of all patients (5.4% of patients who met the MC, 7% of patients who met the UTS criteria, 5.9% of patients who met the Asan criteria, and 6.3% of patients who had an AFP score less than 2) experienced recurrence. CONCLUSIONS: The outcomes of the patients were comparable to those reported in the current literature. In our population, similar recurrence and survival rates of the patients were noted for patients fulfilling the UTS criteria irrespective of fulfilling or exceeding the MC. Consequently, we consider using UTS criteria as the extended criterion for LTx indication.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Estudos Retrospectivos , Fatores de Risco
11.
Regul Toxicol Pharmacol ; 116: 104714, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32640299

RESUMO

A review of pharmacokinetic and metabolism studies show that triclopyr is well absorbed from the oral route in numerous species (≥80%), primarily as parent compound. Absorption is quite rapid in rats, dogs and human volunteers. Plasma or blood clearance is also rapid (t1/2 3-9 h), except for dog (12-96 h). Systemic exposure is not dose-proportional: in the rat above 20 mg/kg (dietary) or between 3 and 60 mg/kg (gavage), or in dogs above 5 mg/kg, with systemic exposure in human more comparable to rat than dog. Triclopyr is highly bound to protein in rat, dog and human plasma (≥97% at or below 7 µg/mL), indicating that species differences in systemic exposure are not due to differences in the free fraction of this test material in plasma. An in vitro flux study in renal proximal tubule cells showed that net renal transport of triclopyr is in the direction of secretion in rat and human donors, while reabsorption predominated in the dog, possibly via organic anion transporters such as OAT1/3. These results fit well into the framework of utilizing metabolism and toxicokinetics across species and exposure levels to allow for toxicity testing in the most relevant species as well as at proper dose levels.


Assuntos
Glicolatos/farmacocinética , Herbicidas/farmacocinética , Animais , Humanos , Medição de Risco
12.
Z Gastroenterol ; 58(1): 63-67, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931542

RESUMO

We report the case of a 65-year-old female patient with hepatic alveolar echinococcosis (AE) caused by Echinococcus multilocularis. This infrequent zoonosis has a considerable morbidity and mortality. The malignant appearing hepatic mass was initially misdiagnosed as cholangiocarcinoma of the right hepatic lobe (segments VII, VIII, and IVa, sized 10.9 cm × 7.6 cm) involving the right and middle hepatic vein and extending close to the left hepatic vein. During exploratory laparotomy, the frozen-section biopsy was indicative of AE (World Health Organization [WHO] classification: stage P3N0M0). Due to the high operative risk, it was decided to pretreat the patient with albendazole as inductive therapy in order to remove the AE secondarily in accordance with the patient's request. After year-long treatment with albendazole (under strict control of the maximum blood levels), a right hemihepatectomy was successfully performed. Postoperative treatment with albendazole had to be stopped prematurely after 11 months due to considerable subjective intolerance and a more-than-tenfold elevation of transaminases despite normal therapeutic albendazole blood levels. A 18F-FDG-PET/CT scan revealed no evidence of AE residues. Conducting follow-up examinations by 18F-FDG-PET/CT scans every 2 years is planned in order to recognize possible recurrence at an early stage.


Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Equinococose Hepática/terapia , Echinococcus multilocularis/isolamento & purificação , Tomografia por Emissão de Pósitrons/métodos , Idoso , Animais , Equinococose Hepática/diagnóstico por imagem , Equinococose Hepática/parasitologia , Echinococcus multilocularis/efeitos dos fármacos , Feminino , Fluordesoxiglucose F18 , Hepatectomia , Humanos , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Resultado do Tratamento
13.
Anticancer Res ; 40(1): 1-7, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892548

RESUMO

BACKGROUND/AIM: The treatment of colorectal liver metastases is challenging and requires multidisciplinary strategies. Unfortunately, only 25% of patients with colorectal liver metastases are eligible for liver resection. Due to the variety of therapeutic approaches, this percentage has increased; however, at the same time, the definition of resectability has become complex. The aim of this review was to provide an overview of current surgical therapies for colorectal liver metastases. MATERIALS AND METHODS: Relevant studies published before June 2019 were identified using PubMed. A comprehensive review of the current literature regarding the impact of and innovations in the therapy of colorectal liver metastases was carried out. RESULTS: The major advances in the resectability of colorectal liver metastases were effective chemotherapy regimens and preoperative liver volume modulation techniques. In addition, health professionals face rapid technical developments in interventional local therapies, minimally invasive surgery, robot-assisted surgery and even liver transplantation. CONCLUSION: Currently, liver metastases from colorectal cancer are considered a chronic disease. In cases of advanced colorectal liver metastases, the definition of resectability and the indications for surgical treatment should be exclusively determined by experienced hepatobiliary surgeons.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Doença Crônica , Neoplasias Colorretais/epidemiologia , Terapia Combinada , Gerenciamento Clínico , Humanos , Incidência , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Resultado do Tratamento
14.
Crit Rev Toxicol ; 50(10): 836-860, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33528302

RESUMO

1,3-Dichloropropene (1,3-D; CAS #542-75-6) is a fumigant used for preplant treatment of soil to control parasitic nematodes and manage soil borne diseases for numerous fruit, vegetable, field and tree and vine crops across diverse global agricultural areas. In the USA, 1,3-D has historically been classified by the U.S. EPA as likely to be carcinogenic to humans via both oral and inhalation routes. This classification for the oral route was primarily based upon increases in multiple tumor types observed in National Toxicology Program (NTP) cancer bioassays in rats and mice, while the classification for the inhalation route was based upon increased benign bronchioloalveolar adenomas in a mouse study conducted by The Dow Chemical Company. Based on U.S. EPA standard risk assessment methodologies, a low-dose linear extrapolation approach has been used to estimate risks to humans. Furthermore, genotoxicity associated with 1,3-D was historically considered a potential mode of action (MOA) for its tumorigenicity. New information is available and additional studies have been conducted that reveal a different picture of the tumorigenic potential of 1,3-D. These data and information include: (1) initial cancer studies by the NTP were conducted on an antiquated form of 1,3-D which contained a known mutagen/carcinogen, epichlorohydrin, as a stabilizer while current 1,3-D fumigants use epoxidized soybean oil (ESO) as the stabilizer; (2) results from two additional oral rodent cancer bioassays conducted on the modern form of 1,3-D became available and these two studies reveal a lack of carcinogenicity; (3) a newly conducted Big Blue study in F344 rats via the oral route further confirms that 1,3-D is not an in vivo genotoxicant; and (4) a newly conducted repeat dose inhalation toxicokinetic (TK) study shows that linear dose proportionality is observed below 30 ppm, which demonstrates the non-relevance of 60 ppm 1,3-D-induced benign lung tumors in mice for human health assessment. This weight of evidence review is organized as follows: (a) the TK of 1,3-D are presented because of relevant considerations when evaluating test doses/concentrations and reported findings of tumorigenicity; (b) the genotoxicity profile of 1,3-D is presented, including a contemporary study in order to put a possible genotoxicity MOA into perspective; (c) the six available bioassays are reviewed followed by (d) scientifically supported points of departure (PODs) and evaluation of human exposure for use in risk assessment. Through this assessment, all available data support the conclusion that 1,3-D is not a tumorigen at doses below 12.5 mg/kg bw/day via the oral route or at doses below 30 ppm via the inhalation route. These findings and clearly identified PODs show that a linear low dose extrapolation approach is not appropriate and a threshold-based risk assessment for 1,3-D is human health protective. Finally, in 2019, the Cancer Assessment Review Committee (CARC) reevaluated the carcinogenic potential of 1,3-D. In accordance with the EPA's Final Guidelines for Carcinogen Risk Assessment, the CARC classified 1,3-D (Telone) as "Suggestive Evidence of Carcinogenic Potential based on the presence of liver tumors by the oral route in male rats only." Given this finding, EPA stated that "quantification of human cancer risk is not required. The CARC recommends using a non-linear approach (i.e. reference dose (RfD)) that will adequately account for all chronic toxicity including carcinogenicity, that could result from exposure to 1,3-dichloropropene."


Assuntos
Compostos Alílicos/toxicidade , Carcinógenos/toxicidade , Hidrocarbonetos Clorados/toxicidade , Praguicidas/toxicidade , Animais , Peso Corporal , Testes de Carcinogenicidade , Humanos , Camundongos , Mutagênicos , Ratos , Ratos Endogâmicos F344 , Medição de Risco
15.
Toxicol Sci ; 174(1): 16-24, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31808915

RESUMO

1,3-Dichloropropene (1,3-D) showed a statistically increased incidence of bronchioloalveolar adenomas in male B6C3F1 mice at 60 ppm air concentration during previous chronic inhalation testing. No tumors were observed in female mice, nor in either sex of F344 rats up to 60 ppm, the highest dose tested. Therefore, to understand if lung tumors observed in high dose male mice are due to saturation of metabolic clearance, the linearity of 1,3-D concentrations in mouse blood was investigated on day 15 of repeated nose-only inhalation exposure to 0, 10, 20, 40, 60, 90, and 120 ppm (6 h/d, 7 d/week). Additional groups were included at 20, 60, and 120 ppm for blood collection at 1.5 and 3 h of exposure and up to 25 or 40 min post-exposure to determine area-under-the-curve. The data provide multiple lines of evidence that systemic exposures to 1,3-D in the mouse become nonlinear at inhalation exposure levels of 30 ppm or above. A reduction in minute volume occurred at the highest exposure concentration. The glutathione (GSH)-dependent metabolism of 1,3-D results in significant depletion of GSH at repeated exposure levels of 30 ppm and above. This loss of GSH results in decreased metabolic clearance of this test material, with a concomitant increase of the 1,3-D isomers in circulating blood at exposure concentrations ≥30 ppm. Shifts in the ratio of cis- and trans-1,3-D also support nonlinear toxicokinetics well below 60 ppm. Based on this data, a kinetically derived maximum dose for 1,3-D in mice for repeated exposures should be at or below 30 ppm. These results support non-relevance of 1,3-D-induced benign pulmonary tumorigenicity in mice for human health risk assessment.


Assuntos
Adenoma/induzido quimicamente , Compostos Alílicos/toxicidade , Carcinógenos/toxicidade , Hidrocarbonetos Clorados/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Pulmão/efeitos dos fármacos , Modelos Teóricos , Adenoma/metabolismo , Compostos Alílicos/sangue , Compostos Alílicos/farmacocinética , Animais , Carcinógenos/metabolismo , Carcinógenos/farmacocinética , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Relação Dose-Resposta a Droga , Feminino , Hidrocarbonetos Clorados/sangue , Hidrocarbonetos Clorados/farmacocinética , Exposição por Inalação , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Dinâmica não Linear , Ratos Endogâmicos F344 , Taxa Respiratória/efeitos dos fármacos , Medição de Risco , Fatores Sexuais , Distribuição Tecidual , Toxicocinética
16.
Biomarkers ; 25(1): 62-68, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31701763

RESUMO

Context: Alcoholic liver cirrhosis is a significant risk factor for the development of hepatocellular carcinoma (HCC). The importance of tumour-associated cirrhosis in the development or progression of HCC is not understood. MiRNAs are important regulators for HCC development, but their role in HCC due to alcoholic liver cirrhosis is unclear.Objective: The aim of this study is the detection of miRNA expression in alcoholic liver cirrhosis, tumour-associated cirrhosis, and HCC.Materials and methods: We analysed the differences in the miRNA profiles of HCC, tumour-associated cirrhosis, and cirrhosis without HCC samples from 30 patients who underwent liver transplantation because of alcoholic liver disease.Results: Microarray analyses revealed 40 significantly differentially expressed miRNAs between HCC tissue and tumour-associated cirrhosis tissue. Furthermore, the microarray analysis discovered 56 differentially expressed miRNAs in tumour-associated cirrhosis and cirrhosis without HCC.Discussion: The differences of miRNA profile in alcoholic liver cirrhosis with and without HCC could improve understanding of HCC development, as well as lead to a new diagnostic tool in HCC screening.Conclusion: We were able to show for the first time, the differences of miRNA profile as promising biomarker in HCC, tumour-associated cirrhosis, and cirrhosis without HCC in context of alcoholic liver disease.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Cirrose Hepática Alcoólica/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Transcriptoma , Adulto , Carcinoma Hepatocelular/etiologia , Feminino , Alemanha , Humanos , Cirrose Hepática Alcoólica/etiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade
17.
World J Gastroenterol ; 25(43): 6430-6439, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31798279

RESUMO

BACKGROUND: Segmental intrahepatic cholestasis caused by transjugular intrahepatic portosystemic shunt (TIPS) (SIC-T), is a rare complication of this technique and only referred by case reports. Thus, we conducted a systematic, retrospective analysis to provide evidence regarding prevalence and consequences of this TIPS-induced bile duct compression. AIM: To assess prevalence and outcome of SIC-T in a large TIPS-cohort. METHODS: In this retrospective cohort study, we screened the institutional databases for all consecutive patients that were treated by TIPS-placement or TIPS-revision between January 2005 and August 2013. We analyzed radiologic images for signs of biliary congestion. Cases that were indicative of SIC-T were reviewed by two independent radiologists and additional patient data was collected. Descriptive statistics of patient demographics, indications for TIPS and procedural details were registered. Logistic regression analysis was performed to identify predictors for the development of SIC-T. RESULTS: We analyzed 135 cirrhotic patients who underwent TIPS (mean age 55 years, 79% male gender). Etiology of cirrhosis was alcohol in most cases and indications for TIPS were mainly refractory ascites and recurrent variceal bleeding. TIPS revision was necessary in 31 patients. We identified 4 cases (2.9%) of SIC-T in direct proximity of the TIPS-stent. Diagnosis was confirmed by CT-scan, MRI or endoscopic retrograde cholangio pancreaticography (ERCP). In two patients TIPS was implanted via the right and in one through the medial hepatic vein. One patient received TIPS-prolongation by multiple revisions. Most patients were asymptomatic but one cholangitic abscess necessitated a transhepatic drain. Logistic regression analysis identified TIPS-placement other than from medial hepatic vein to right portal vein as risk factor (OR 21.0) for SIC-T. CONCLUSION: SIC-T ads to (mostly late) complications in the interventional treatment of cirrhotic portal hypertensions and can lead to cholangitic abscesses. Patients, particularly with multiple interventions, should be screened for SIC-T.


Assuntos
Colestase Intra-Hepática/etiologia , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Colestase Intra-Hepática/diagnóstico por imagem , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
18.
Ann Transplant ; 24: 527-531, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31515466

RESUMO

BACKGROUND There is an unmet need to improve the HBV vaccination status in patients with chronic liver diseases. Primary care physicians and outpatient hepatologists often fail to vaccinate as recommended. Thus, new strategies to improve the HBV vaccination rate are required. MATERIAL AND METHODS This study was performed in a cohort of patients with chronic liver diseases evaluated for liver transplantation. Vaccination status was taken from the patients' vaccination cards. HBsAg-, anti-HBc-, and anti-HBs-negative individuals were vaccinated against HBV at hospital discharge, and subsequent outpatient completion of the standard vaccination protocol was recommended in detail in the discharge letter. At months 2 and 8, titer controls were performed, and completion of vaccination was evaluated. RESULTS We prospectively recruited 37 patients. At baseline, the vaccination rate against HBV was 24% (N=9/37), and 3/9 HBV vaccinated patients presented with an anti-HBs-titer >10 IU/L. Thus, N=34 were vaccinated with Engerix® or Twinrix®. We evaluated 26/34 patients at month 2 and 10/26 again at month 8. The second vaccine dose was obtained by 21/26 (80%) of the patients seen at month 2, and 9/10 (90%) seen at month 8 obtained the third vaccine dose by primary care physicians or ambulant hepatologists. Only 2 patients presented with an anti-HBs-titer >10 IU/L at month 8. CONCLUSIONS Initiation of HBV vaccination during hospitalization and detailed recommendations on subsequent vaccinations in the discharge letter improve previously inadequate vaccination rates in the outpatient setting. Similar measures should be implemented at earlier time points of chronic liver diseases to achieve higher immune response rates.


Assuntos
Hepatite B/prevenção & controle , Cirrose Hepática/patologia , Transplante de Fígado , Vacinas contra Hepatite Viral , Adulto , Idoso , Feminino , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Prospectivos
19.
Regul Toxicol Pharmacol ; 108: 104438, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31461669

RESUMO

Herein, we publish data from regulatory studies investigating the oral ADME (absorption, distribution, metabolism, excretion) of tricyclazole in vivo, in silico and in vitro. The oral route is relevant to human dietary exposure assessment. Tricyclazole is readily absorbed and highly bioavailable in rodents (>86%) with indication of saturation of absorption at high doses. Enterohepatic recirculation is evident. Excretion occurs quickly both via urinary (31-64%) and faecal routes (39-65%), with substantial biliary elimination in the rat (≥58%). The tricyclazole-derived radioactivity is distributed to major organs, including those investigated in in vivo genotoxicity studies (liver, kidney, gastrointestinal tract and bone marrow). There is no evidence of bioaccumulation. Metabolism is extensive (approximately 30 metabolites), with the liver being identified as the primary metabolism organ with Phase I and II enzymes involved. Several metabolites are formed following an initial cleavage of the central thiazole ring, with no loss of free triazole from the remaining phenyl ring. A group of 4 metabolites derive from an initial oxidation step with the formation of the tricyclazole-alcohol, a relevant crop metabolite, and account for up to 13% of the administered dose. In vitro metabolism, investigated with liver microsomes, confirmed that humans do not form unique metabolites.


Assuntos
Fungicidas Industriais/farmacocinética , Tiazóis/farmacocinética , Administração Oral , Animais , Humanos , Medição de Risco
20.
J Hepatol ; 71(2): 313-322, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31071367

RESUMO

BACKGROUND & AIMS: Little is known about outcomes of liver transplantation for patients with non-alcoholic steatohepatitis (NASH). We aimed to determine the frequency and outcomes of liver transplantation for patients with NASH in Europe and identify prognostic factors. METHODS: We analysed data from patients transplanted for end-stage liver disease between January 2002 and December 2016 using the European Liver Transplant Registry database. We compared data between patients with NASH versus other aetiologies. The principle endpoints were patient and overall allograft survival. RESULTS: Among 68,950 adults undergoing first liver transplantation, 4.0% were transplanted for NASH - an increase from 1.2% in 2002 to 8.4% in 2016. A greater proportion of patients transplanted for NASH (39.1%) had hepatocellular carcinoma (HCC) than non-NASH patients (28.9%, p <0.001). NASH was not significantly associated with survival of patients (hazard ratio [HR] 1.02, p = 0.713) or grafts (HR 0.99; p = 0.815) after accounting for available recipient and donor variables. Infection (24.0%) and cardio/cerebrovascular complications (5.3%) were the commonest causes of death in patients with NASH without HCC. Increasing recipient age (61-65 years: HR 2.07, p <0.001; >65: HR 1.72, p = 0.017), elevated model for end-stage liver disease score (>23: HR 1.48, p = 0.048) and low (<18.5 kg/m2: HR 4.29, p = 0.048) or high (>40 kg/m2: HR 1.96, p = 0.012) recipient body mass index independently predicted death in patients transplanted for NASH without HCC. Data must be interpreted in the context of absent recognised confounders, such as pre-morbid metabolic risk factors. CONCLUSIONS: The number and proportion of liver transplants performed for NASH in Europe has increased from 2002 through 2016. HCC was more common in patients transplanted with NASH. Survival of patients and grafts in patients with NASH is comparable to that of other disease indications. LAY SUMMARY: The prevalence of non-alcoholic fatty liver disease has increased dramatically in parallel with the worldwide increase in obesity and diabetes. Its progressive form, non-alcoholic steatohepatitis, is a growing indication for liver transplantation in Europe, with good overall outcomes reported. However, careful risk factor assessment is required to maintain favourable post-transplant outcomes in patients with non-alcoholic steatohepatitis.


Assuntos
Doença Hepática Terminal/cirurgia , Sobrevivência de Enxerto , Transplante de Fígado/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/cirurgia , Adulto , Fatores Etários , Índice de Massa Corporal , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Europa (Continente) , Feminino , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/mortalidade , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos , Resultado do Tratamento
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