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In this work, inelastic neutron scattering (INS) spectroscopy is used to investigate the impact of entropic factors on the behaviour of deep eutectic solvents (DES). Periodic density functional theory calculations (DFT) provide a reliable assignment of the vibrational modes of pure compounds. This assignment guides the analysis of INS spectra of binary mixtures - with particular attention to methyl torsional modes. Deviations from ideality in the mixtures of tetraalkylammonium salts with urea are readily determined through a simplified thermodynamic approach. This study reports and discusses the relationship between the cation's asymmetry, the INS spectra of the eutectic mixture and its deviation from ideality. Contrary to the majority of systems studied so far, the deep eutectic system comprised of [N2,2,2,1]Cl and urea appears to owe its deviation from ideality to entropic rather than enthalpic factors.
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BACKGROUND AND AIMS: Severe indeterminate acute hepatitis (sIAH) is a poorly understood rare disease with no specific therapy. This study aims to define the clinicopathological characteristics of sIAH and the role of liver biopsy in determining prognosis. METHODS: Patients with sIAH admitted to a single center between 2010 and 2019 were included. Histopathological patterns of liver biopsies were reviewed by 2 histopathologists, and key findings further were specified by multiplex immunofluorescence. Patients that died or underwent liver transplantation were analyzed as nonsurvivors. RESULTS: Of 294 patients with acute hepatitis, 43 with sIAH were included. Seventeen (39.5%) underwent liver transplantation and 7 (16.2%) died within 3 months. Multilobular necrosis was the predominant histopathological feature, being significantly more frequent in nonsurvivors (62.5% vs 21.1%; P = .016). Necrotic areas showed low HNF4α and Ki67 expression but high expression of CK19 and cell death markers identifying areas of severe tissue injury and inadequate regenerative response. Patients with multilobular necrosis had higher international normalized ratio, Model for End-Stage Liver Disease, and Model for End-Stage Liver Disease-Sodium scores compared with those without (P values for all markers <.05). Multivariate Cox analysis revealed that multilobular necrosis (hazard ratio, 3.675; 95% confidence interval, 1.322-10.211) and lower body mass index (hazard ratio, 0.916; 95% confidence interval, 0.848-0.991) independently predicted death or transplantation. CONCLUSIONS: The results of this study provide novel insights into the important role of liver biopsy in sIAH patients, suggesting that the presence of multilobular necrosis is an early indicator of poor prognosis.
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Doença Hepática Terminal , Hepatite , Doença Aguda , Biópsia , Humanos , Necrose , Prognóstico , Índice de Gravidade de DoençaRESUMO
BACKGROUND AND AIMS: Treatment of patients with severe indeterminate hepatitis (IAH) is an unmet need. Corticosteroids are often used in the management of these patients but criteria for the selection of patients for this intervention are arbitrary. The aims of this study were to analyse the clinical and pathological features of patients with IAH to define predictors of corticosteroid responsiveness. METHODS: This study included consecutive patients with acute indeterminate hepatitis admitted to a single hospital and underwent a liver biopsy. The clinical manifestation and histopathological features of steroid and non-steroid groups were compared and their relationship with corticosteroids response was evaluated. RESULTS: Forty-eight patients were included, 24 (50%) recovered and the other half underwent liver transplantation or died within 3-months. Of the 48 cases, 24 received corticosteroids (initial dose of 45 ± 12 mg prednisolone). Corticosteroids were initiated 2.7 ± 3.8 days after admission. Liver biopsy was performed 2-days (median, IQR 1-3) after admission. Fifteen (62.5%) patients receiving corticosteroids survived without transplantation compared with 9 (37.5%) that did not receive steroids (P = .149). In those with multilobular necrosis, 50% reduction in the death/transplantation rate was observed after steroid treatment (P = .018). In patients without multilobular necrosis and with or without perivenulitis, corticosteroids did not impact the outcome. Response to corticosteroids was independent of the MELD score. CONCLUSIONS: The presence of multilobular necrosis on liver biopsy helps identify a subgroup of IAH cases who may benefit from the administration of corticosteroids.
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Corticosteroides , Hepatite , Corticosteroides/uso terapêutico , Biópsia , Hepatite/tratamento farmacológico , Humanos , Necrose , Resultado do TratamentoRESUMO
The present work emphasizes the value of periodic density functional theory (DFT) calculations in the assessment of the vibrational spectra of molecular crystals. Periodic calculations provide a nearly one-to-one match between the calculated and observed bands in the inelastic neutron scattering (INS) spectrum of crystalline 4-phenylbenzaldehyde, thus validating their assignment and correcting previous reports based on single molecule calculations. The calculations allow the unambiguous assignment of the phenyl torsional mode at ca. 118-128 cm-1, from which a phenyl torsional barrier of ca. 4000 cm-1 is derived, and the identification of the collective mode involving the antitranslational motion of CH···O bonded pairs, a hallmark vibrational mode of systems where C-H···O contacts are an important feature.
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Compostos de Bifenilo/química , Modelos Moleculares , Estrutura Molecular , Espectrofotometria InfravermelhoRESUMO
Bacterial nanocellulose (BC)-based composites containing poly(2-hydroxyethyl methacrylate) (PHEMA), poly(methacroylcholine chloride) (PMACC) or poly(methacroylcholine hydroxide) (PMACH) were characterized by inelastic neutron scattering (INS) spectroscopy, combined with DFT (density functional theory) calculations of model systems. A reasonable match between calculated and experimental spectral lines and their intensities was used to support the vibrational assignment of the observed bands and to validate the possible structures. The differences between the spectra of the nanocomposites and the pure precursors indicate that interactions between the components are stronger for the ionic poly(methacrylate) derivatives than for the neutral counterpart. Displaced anions interact differently with cellulose chains, due to the different ability to compete with the O-H···O hydrogen bonds in cellulose. Hence, the INS is an adequate technique to delve deeper into the structure and dynamics of nanocellulose-based composites, confirming that they are true nanocomposite materials instead of simple mixtures of totally independent domains.
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Celulose/química , Metacrilatos/química , Nanocompostos/química , Polímeros/química , Teoria da Densidade Funcional , Ligação de Hidrogênio , Difração de Nêutrons/métodos , Nêutrons , VibraçãoRESUMO
There is a lack of fundamental knowledge on deep eutectic solvents, even for the most extensively studied mixtures, such as the mixture of cholinium chloride and urea, which prevents a judicious choice of components to prepare new solvents. The objective of this work is to study and understand the fundamental interactions between cholinium chloride and urea that lead to the experimentally observed melting temperature depression. To do so, the structure of urea was strategically and progressively modified, in order to block certain interaction centres, and the solid-liquid equilibrium data of each new binary system was experimentally measured. Using this approach, it was concluded that the most important interaction between cholinium chloride and urea occurs through hydrogen bonding between the chloride anion and the amine groups. Any blockage of these groups severely hampers the melting point depression effect. Raman spectroscopy and DFT calculations were utilized to study in more detail this hydrogen bonding and its nuances.
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Infecções por Bactérias Gram-Negativas , Stenotrophomonas maltophilia , Stenotrophomonas maltophilia/isolamento & purificação , Humanos , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/diagnóstico , Antibacterianos/uso terapêutico , MasculinoRESUMO
The parasite Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) can be classified based on biochemical and molecular markers, into six lineages or discrete typing units (DTUs), T. cruzi I-VI (TcI-VI), from which TcI and TcII are the parental genotypes. Trying to understand the dispersion of the subpopulations of T. cruzi in nature and its complex transmission cycles, the serine carboxypeptidase genes of T. cruzi were used as a molecular marker in the present study. DTUs of 25 T. cruzi isolates derived from different hosts and from different regions of Brazil were classified. Using specific primers, the complete serine carboxypeptidase open reading frame of 1401 bp was sequenced. The obtained data shows significant differences in the sequences of TcI and TcII. The analysis of the T. cruzi significantly different serine carboxypeptidase genes allowed distinguishing between the parental DTUs TcI to TcII and the hybrid DTU TcVI which grouped within the latter branch. The sequence diversity within the T. cruzi subpopulations was rather low. The analysis using the genes encoding proteases seems to be an interesting approach for the reconstruction of the origin and genotype evolution of T. cruzi.
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Carboxipeptidases/genética , Doença de Chagas/parasitologia , Proteínas de Protozoários/genética , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/genética , Evolução Biológica , Brasil , Genótipo , Humanos , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
Insects possess both cellular and humoral immune responses. The latter makes them capable to recognize and control invading pathogens after synthesis of a variety of small proteins, also known as antimicrobial peptides. Defensins, cysteine-rich cationic peptides with major activity against Gram-positive bacteria, are one ubiquitous class of antimicrobial peptides, widely distributed in different animal and plant taxa. Regarding triatomines in each of the so far analyzed species, various defensin gene isoforms have been identified. In the present study, these genes were sequenced and used as a molecular marker for phylogenetic analysis. Considering the vectors of Chagas disease the authors are reporting for the first time the presence of these genes in Triatoma sordida (Stål, 1859), Rhodnius nasutus (Stål, 1859), and Panstrongylus megistus (Burmeister, 1835). Members of the Triatoma brasiliensis species complex were included into the study to verify the genetic variability within these taxa. Mainly in their mature peptide, the deduced defensin amino acid sequences were highly conserved. In the dendrogram based on defensin encoding nucleotide, sequences the Triatoma Def3/4 genes were separated from the rest. In the dendrogram based on deduced amino acid sequences the Triatoma Def2/3/4 together with Rhodnius DefA/B pre-propeptides were separated from the rest. In the sub-branches of both the DNA and amino acid dendrograms, the genus Triatoma was separated from the genus Rhodnius as well as from P. megistus.
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Doença de Chagas/transmissão , Defensinas/genética , Proteínas de Insetos/genética , Insetos Vetores/genética , Panstrongylus/genética , Filogenia , Rhodnius/genética , Triatoma/genética , Sequência de Aminoácidos , Animais , Defensinas/química , Defensinas/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Insetos Vetores/classificação , Insetos Vetores/fisiologia , Dados de Sequência Molecular , Panstrongylus/classificação , Panstrongylus/fisiologia , Rhodnius/classificação , Rhodnius/fisiologia , Alinhamento de Sequência , Triatoma/classificação , Triatoma/fisiologiaRESUMO
BACKGROUND: Atopic dermatitis (AD) is a disease with multifactorial etiology. Staphylococcus aureus is one of the predominant environmental factors acting on the course and intensity of the disease. OBJECTIVES: The aims of the study were to evaluate the efficacy and safety of clothing made of cellulose fibers with seaweed enriched with silver ions in the treatment of children with AD. METHODS: A prospective, randomized and double-blinded controlled selection was done to recruit 19 children with diagnosis of AD. This sample was divided in two groups with similar demographic and clinical characteristics (the "control" group of seven children who wore placebo clothing and the "trial textile" group of 12 children who wore clothing with the new textile). The severity of AD and clinical response were assessed by the SCORAD index, the intensity of pruritus and the changes in sleep characteristics, at the start of the study and after 7 and 90 d. RESULTS: The SCORAD index improvement in the group with the fiber under study was statistically significant after the first 7 d of treatment (p < 0.001) and was reduced by about 45% after 90 d. There was also a statistically relevant reduction of the intensity of pruritus and an improvement in the sleep quality after the initial 7 d and at day 90. CONCLUSION: The results showed that the textile clothing with seaweed enriched with silver ions brings a quicker improvement of the patients in the first days in opposition to the use of standard all-cotton clothes. The results also reinforce the importance of non-pharmacological measures, like clothing, in the management of patients with a diagnosis of AD.
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Antibacterianos , Fibra de Algodão , Dermatite Atópica/terapia , Alga Marinha , Prata , Têxteis , Celulose , Criança , Pré-Escolar , Misturas Complexas/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prurido/terapiaRESUMO
Schimmelpenning syndrome (SS) includes an organoid nevus that follows the lines of Blaschko and defects of brain, eyes, bones, or other systems. We report a case of a 3-month old female infant, who presented with several thin plaques, with irregular borders, yellowish color, which had a verrucous appearance, following the lines of Blaschko, mainly occupying the left side of posterior trunk, the left face, the right side of the anterior trunk, and the right upper limb. These plaques had been present since birth. In addition, she had a flat salmon to yellow nevus on the left parietal and temporal region of the scalp, with a bald patch. She was diagnosed after birth with an interauricular communication. The skin biopsy from the lesion of the right arm revealed an epidermal nevus that occupied the epidermis completely. Routine and other complementary laboratory blood tests, including platelet count, thyroid function tests, 25-hydroxy-vitamin D, parathyroid hormone, and plasma and urinary levels of calcium and phosphorus were negative. Cerebral magnetic resonance and renal ultrasound were normal. The diagnosis of SS was established. She is being followed in the clinics of Dermatology, Cardiology, Pediatrics, and Pediatric Neurology. We report this case to point out the importance of investigating patients with epidermal nevus to identify associated conditions.
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Nevo Pigmentado/patologia , Nevo Sebáceo de Jadassohn/patologia , Anormalidades da Pele/patologia , Neoplasias Cutâneas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Lactente , NevoRESUMO
A myxozoan survey was performed on specimens of thicklip grey mullet Chelon labrosus (Risso) captured from the Douro River estuary, northern Portugal. Eleven new species, all belonging to the genus Myxobolus Bütschli, 1882 (M. abdominalis n. sp., M. aestuarium n. sp., M. caudalis n. sp., M. chelonari n. sp., M. cucurbitiformis n. sp., M. douroensis n. sp., M. intestinicola n. sp., M. invictus n. sp., M. labicola n. sp., M. peritonaei n. sp., and M. pinnula n. sp.) are described based on microscopic and molecular data, confirming the known high radiation of these myxozoans in mullets. Additionally, Myxobolus pupkoi Gupta et al., 2022 is reported for the first time from C. labrosus, bringing forth a novel case of morphological plasticity between geographic isolates. We consider that molecular-based comparisons are imperative for the description of mugiliform-infecting Myxobolus, with distance estimation further matching two of the novel Myxobolus spp. with sphaeractinomyxon types previously reported from another Portuguese estuary. This finding supports sphaeractinomyxon as specific life cycle counterparts of Myxobolus that infect mullets. Phylogenetic analyses of 18S rDNA retrieved a monophyletic clade of mugiliform-infecting myxobolids comprising well-supported lineages of species parasitizing mullets from the genera Chelon, Mugil, Crenimugil, and Planiliza. The existence of more than one Chelon- and Planiliza-infecting lineage reveals that myxobolids parasitized members of these genera multiple times during their evolution. Lastly, the elevated number of unmatched sphaeractinomyxon sequences included in the Chelon-infecting lineages clearly shows that Myxobolus diversity hosted by this genus remains underrated.
Title: Un inventaire des myxozoaires du mulet lippu Chelon labrosus confirme le rayonnement réussi de Myxobolus chez les hôtes mugiliformes. Abstract: Un inventaire des myxozoaires a été réalisé sur des spécimens de mulets lippus Chelon labrosus (Risso) capturés dans l'estuaire du fleuve Douro, au nord du Portugal. Onze nouvelles espèces, toutes appartenant au genre Myxobolus Bütschli, 1882 (M. abdominalis n. sp., M. aestuarium n. sp., M. caudalis n. sp., M. chelonari n. sp., M. cucurbitiformis n. sp., M. douroensis n. sp., M. intestinicola n. sp., M. invictus n. sp., M. labicola n. sp., M. peritonaei n. sp. et M. pinnula n. sp.) sont décrites sur la base de données microscopiques et moléculaires, confirmant le rayonnement connu de ces myxozoaires chez les mulets. De plus, Myxobolus pupkoi Gupta et al., 2022 est signalé pour la première fois chez C. labrosus, démontrant un nouveau cas de plasticité morphologique entre des isolats géographiques. Nous considérons que les comparaisons moléculaires sont impératives pour la description des Myxobolus infectant les mugiliformes, l'estimation de la distance correspondant en outre à deux des nouveaux Myxobolus spp. avec des types de sphaeractinomyxons précédemment signalés dans un autre estuaire portugais. Cette découverte soutient les sphaeractinomyxons en tant que contreparties spécifiques du cycle de vie de Myxobolus qui infectent les mulets. Les analyses phylogénétiques de l'ADNr 18S ont montré un clade monophylétique de Myxobolidae infectant les mugiliformes, comprenant des lignées robustes d'espèces parasitant les mulets des genres Chelon, Mugil, Crenimugil et Planiliza. L'existence de plusieurs lignées infectant Chelon et Planiliza révèle que les Myxobolidae ont parasité des membres de ces genres plusieurs fois au cours de leur évolution. Enfin, le nombre élevé de séquences de sphaeractinomyxons non appariées incluses dans les lignées infectant Chelon montre clairement que la diversité de Myxobolus hébergée par ce genre reste sous-estimée.
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Doenças dos Peixes , Myxobolus , Myxozoa , Doenças Parasitárias em Animais , Smegmamorpha , Animais , Myxobolus/genética , Filogenia , Rios , BrânquiasRESUMO
Superior vena cava syndrome (SVCS) is caused by any obstruction to the superior vena cava (SVC); the most common causes are malignancy and extrinsic compression. The use of medical devices, such as central venous catheters, poses an important risk factor, as they cause changes in the blood flow and in the vessel wall. This report describes a case of a 70-year-old male with an implantable central venous port, due to previous neoplastic disease, as the cause of the SVCS. Authors advise that the placement of medical devices ought to be carefully accessed and constantly revised to be removed when no longer needed to prevent avoidable complications.
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Symptomatic pericardial effusion occurring as the initial manifestation of Hodgkin's lymphoma is exceedingly uncommon, and there are limited documented instances in the available literature. Pericardial effusion can present various differential diagnoses, and among these, malignancy is an important yet less frequently encountered cause. A heightened level of suspicion is crucial for establishing an accurate diagnosis, particularly when the patient's clinical course deviates from the anticipated trajectory. Through this case, we aim to emphasize the significance of considering lymphoproliferative diseases as a pertinent possibility in the differential diagnosis of pericardial effusion. Additionally, we underscore the importance of promptly reaching a diagnosis, as it can help prevent severe complications and enhance the patient's prognosis.
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The intricate interplay between maternal immune response to SARS-CoV-2 and the transfer of protective factors to the fetus remains unclear. By analyzing mother-neonate dyads from second and third trimester SARS-CoV-2 infections, our study shows that neutralizing antibodies (NAbs) are infrequently detected in cord blood. We uncovered that this is due to impaired IgG-NAb placental transfer in symptomatic infection and to the predominance of maternal SARS-CoV-2 NAbs of the IgA and IgM isotypes, which are prevented from crossing the placenta. Crucially, the balance between maternal antiviral response and transplacental transfer of IgG-NAbs appears to hinge on IL-6 and IL-10 produced in response to SARS-CoV-2 infection. In addition, asymptomatic maternal infection was associated with expansion of anti-SARS-CoV-2 IgM and NK cell frequency. Our findings identify a protective role for IgA/IgM-NAbs in gestational SARS-CoV-2 infection and open the possibility that the maternal immune response to SARS-CoV-2 infection might benefit the neonate in 2 ways, first by skewing maternal immune response toward immediate viral clearance, and second by endowing the neonate with protective mechanisms to curtail horizontal viral transmission in the critical postnatal period, via the priming of IgA/IgM-NAbs to be transferred by the breast milk and via NK cell expansion in the neonate.
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COVID-19 , Gravidez , Recém-Nascido , Humanos , Feminino , SARS-CoV-2 , Placenta , Anticorpos Neutralizantes , Infecções Assintomáticas , Imunoglobulina A , Imunoglobulina M , Antivirais , Imunoglobulina GRESUMO
This work explores the conformational preferences and the structure-property correlations of poly(butylene 2,5-furandicarboxylate) (PBF), a longer chain analogue of the most well-known biobased polyester from the furan family, poly(ethylene 2,5-furandicarboxylate) (PEF). A thorough computational spectroscopic study-including infrared, Raman and inelastic neutron scattering spectroscopy, combined with discrete and periodic density functional theory calculations-allowed the identification of dominant structural motifs in the amorphous and crystalline regions. Discrete calculations and vibrational spectroscopy of semi-crystalline and amorphous samples strongly support the predominance of gauche, trans, gauche conformations of the butylene glycol fragment in both the crystalline and amorphous domains. In what concerns the furandicarboxylate fragment, amorphous domains are dominated by syn,syn conformations, while in the crystalline domains the anti,anti forms prevail. A possible crystalline structure-built from these conformational preferences and including a network of C-H···O hydrogen bond contacts-was optimized using periodic density functional theory. This proposed crystal structure avoids the unrealistic structural features of the previously proposed X-ray structure, provides an excellent description of the inelastic neutron scattering spectrum of the semi-crystalline form, and allows the correlation between microscopic structure and macroscopic properties of the polymer.
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The modern era has brought an appreciation that renal cell carcinoma (RCC) includes diverse subtypes derived from the various parts of the nephron, each with its distinctive genetic basis and tumor biology. Carcinoma of the collecting ducts of Bellini (CDC) is a rare subtype of RCC, with a predictably poor prognosis. This rare subtype represents less than 1% of all kidney carcinomas. It derives from presumably numerous chromosomal losses. It is of chief importance to differentiate CDC from other types of renal cell cancer. Typically, it is characterized by a firm, centrally located tumor with infiltrative borders. Regarding the histopathologic characteristics, we can find complex, highly infiltrative cords with inflamed (desmoplastic) stroma, with high-grade nuclei and mitoses. Most reported cases of CDC had been high grade, advanced stage, and unresponsive to conventional therapies. This rare form of disease highlights the importance of multidisciplinary teams in the management of cancer patients.
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The liver is usually affected in advanced stages of lympho-proliferative diseases, but primary liver lymphomas (PLLs) are rare. The diagnosis is usually late, especially in patients without identifiable risk factors, with consequent worse prognosis. We report the case of a 59-year-old female with progressive worsening pain in the right hypochondrium and weight loss. She was previously healthy and had a family history of gastrointestinal and gynecologic neoplasms. During the initial investigation, three liver nodules suggestive of liver metastases were found. Nevertheless, no primary neoplasm was identified in a subsequent evaluation with imaging and endoscopic exams. Laboratory exams excluded hepatic infections, metabolic diseases, and acquired immunosuppression. Biopsy of the lesions revealed diffuse large B-cell lymphoma. Lymph node and medullar involvement were excluded, and the diagnosis of PLL was assumed. The patient started chemotherapy with R-CHOP. With this case, we intend to alert for this differential diagnosis of liver nodules, even in the absence of predisposing conditions for lymphoma. We point out the need to define universal diagnosis criteria for this pathology.
O fígado é geralmente afetado em estádios avançados de doenças linfoproliferativas, mas os linfomas primários do fígado são raros. O diagnóstico é habitualmente tardio, principalmente em doente sem fatores de risco identificados, e consequentemente com pior prognóstico. Apresentamos o caso de uma doente de 59 anos, com quadro álgico de intensidade crescente no hipocôndrio direito e perda ponderal. A doente era previamente saudável e tinha história familiar de neoplasia gastrointestinal e ginecológica. No estudo inicial, foram identificadas três imagens nodulares hepáticas sugestivas de metástases. No entanto, não se identificou tumor primário em exames de imagem nem endoscópicos. Foram também excluidas infeções hepáticas, doença metabólica e imunossupressão adquirida. A biópsia das lesões hepáticas revelou tratar-se de linfoma B difuso de grandes células. Foi excluido envolvimento ganglionar e medular pelo que se assumiu o diagnóstico de Linfoma Primário do Fígado. A doente iniciou quimioterapia com R-CHOP. Com este caso pretendemos alertar para a necessidade de equacionar este diagnóstico diferencial de nodulos hepáticos, mesmo na ausência de fatores de risco para linfoma. Também alertamos para a necessidade de se definirem critérios diagnósticos universais para esta patologia.