Morphological and molecular data on Phyllodistomum (Digenea: Gorgoderidae) from Brazil, with the description of a new species parasitizing Hoplias malabaricus (Bloch, 1794) (Osteichthyes, Erythrinidae).

Phyllodistomum pepirense n. sp. is described from the urinary bladder of Hoplias malabaricus (Bloch, 1794), sampled in the Jacaré-Pepira River in São Paulo state, Brazil. The isolates of the new species were recovered as a monophyletic group in the phylogenetic analysis of the 28S rRNA gene, which showed the new species as the sister taxa of Phyllodistomum virmantasi Pinacho-Pinacho, Sereno-Uribe, Hernández-Orts, García-Varela & Pérez-Ponce de León, 2021, a species sampled from an eleotrid fish in Southeastern Mexico. The new species differs morphologically from P. virmantasi by having a larger body size, slightly lobed testes and ovary, a mostly intercaecal uterus, slightly diverticulated caeca, and vitelline masses irregularly shaped. The new species is also readily distinguished from other species of Phyllodistomum Braun, 1899 reported from freshwater fishes in Brazil - namely, P. rhamdiae Amato & Amato, 1993 and P. spatula Odhner, 1902. The new species is herein described based on morphological characteristics, molecular data from D1-D3 domains of the 28S rRNA gene, host association, and geographical distribution.

Feeding behavior of feedlot lambs fed diets with different energy and protein sources.

This study aimed to evaluate the effect of the replacement of ground corn by crude glycerin and soybean meal by cottonseed cake, in association or not, on feedlot lambs' feeding behavior. Thirty-two non-castrated crossbred ½ Dorper ½ Santa Inês lambs, with an average body weight of 18.52 ± 3.24 kg (mean ± standard deviation), were distributed in a completely randomized design, into four treatments and eight replicates per treatment, in a 2 × 2 factorial scheme. Four experimental diets were tested with different sources or combinations of energy and protein ingredients in the concentrate, respectively: (1) ground corn + soybean meal; (2) ground corn and cottonseed cake; (3) crude glycerin and soybean meal; and (4) crude glycerin and cottonseed cake. The glycerin decreased dry matter (DM) and neutral detergent fiber (NDF) (P < 0.001) intakes, whereas it increased times spent in feeding (P = 0.009; from 21.8 to 28.6), rumination (P = 0.006; from 56.2 to 67.2), and chewing (P < 0.001; from 79.4 to 97.2), in minutes/100 g of DM. Feeding efficiencies of DM (P = 0.003) and NDF (P = 0.008) were decreased by the diets. Protein sources increased (P = 0.018) the times spent in chewing and per period in rumination (P = 0.014). Cottonseed cake, as a protein source, up to a 112 g/kg DM level, can totally replace soybean meal in diets for feedlot lambs without effects on the intake, behavioral activities, and feeding efficiencies. In contrast, the crude glycerin energy source is not adequate to replace ground corn in lambs' diets.

CD40 Ligand Deficiency.

CD40 ligand deficiency (CD40L), currently classified as an inborn error of immunity affecting cellular and humoral immunity, prevalently emerges in boys within the first two years of life. It manifests itself as a decrease in serum IgG, IgA and IgE, with normal or high IgM, defects in T cell proliferation, and decrease in soluble CD40L. These accompany sinopulmonary and/or gastrointestinal infections, and there may be infections caused by pyogenic bacteria, opportunistic infections, autoimmune diseases, and neoplasms. Mild and moderate cases of this deficiency may respond well to prophylactic antibiotic therapy or to human immunoglobulin replacement therapy, in addition to the early treatment of infections. Severe cases can be treated with hematopoietic stem cell transplantation, which allows the healing of such patients, rather than sequelae and a poor progression. Thus, its differential diagnosis with other inborn errors of immunity is essential, especially CD40 deficiency and variable common immunodeficiency; the reason why we have proposed the present literature review.

Single-cell sequencing unveils the lifestyle and CRISPR-based population history of Hydrotalea sp. in acid mine drainage.

Acid mine drainage (AMD) is characterized by an acid and metal-rich run-off that originates from mining systems. Despite having been studied for many decades, much remains unknown about the microbial community dynamics in AMD sites, especially during their early development, when the acidity is moderate. Here, we describe draft genome assemblies from single cells retrieved from an early-stage AMD sample. These cells belong to the genus Hydrotalea and are closely related to Hydrotalea flava. The phylogeny and average nucleotide identity analysis suggest that all single amplified genomes (SAGs) form two clades that may represent different strains. These cells have the genomic potential for denitrification, copper and other metal resistance. Two coexisting CRISPR-Cas loci were recovered across SAGs, and we observed heterogeneity in the population with regard to the spacer sequences, together with the loss of trailer-end spacers. Our results suggest that the genomes of Hydrotalea sp. strains studied here are adjusting to a quickly changing selective pressure at the microhabitat scale, and an important form of this selective pressure is infection by foreign DNA.

Rational selection of broadly cross-reactive family 2 PspA molecules for inclusion in chimeric pneumococcal vaccines.

Pneumococcal surface protein A (PspA) is a widely studied pneumococcal protein, exposed at the surface of all strains. It is an important virulence factor, preventing complement deposition as well as inhibiting the lytic effects of lactoferrin over pneumococci. Several studies have investigated the use of PspA as a candidate in alternative pneumococcal vaccines, with great success. However, PspA presents sequence variability - there are six clades, grouped in three families - and PspAs within the same clade exhibit different levels of cross-reactivity. Therefore, the aim of this work was to select, from a panel of eight pneumococcal isolates expressing family 2 PspAs, the molecule with the broadest reactivity within this family. Antisera to these PspA fragments were initially screened by immunoblot against thirteen pneumococcal extracts; the three most cross-reactive antisera were tested for their ability to enhance the deposition of complement factor C3b on the bacterial surface and to promote their phagocytosis in vitro. PspA from strain P490 was the most effective, increasing phagocytosis of all but one pneumococcal isolate. Thus, this molecule was selected for inclusion in chimeric protein-based pneumococcal vaccines. In conclusion, the rational selection of cross-reactive molecules is an important step in the development of vaccines with broad coverage.

Genetic diversity of Bacillus sp producers of amylase isolated from the soil.

The microorganisms are the best source of extracellular enzymes since they allow an economical technology with low-resource consumption compared to animals and plants. The amylases are among the most important enzymes being the genus Bacillus one of the most investigated due to its ability to produce this enzyme. The objective of this study was to isolate and analyze the genetic diversity among bacteria of the genus Bacillus sp producer of amylase originated from the soil. To this end, soil samples were collected and submitted to the condition of extreme temperature. The serial dilution procedure followed by seeding on solid medium containing starch was used for isolation of strains that produce amylase. The microorganisms isolated were subjected to standard morphological methods for presumptive identification of the genus Bacillus. The PCR assay with the universal genetic marker 16S rDNA was used for confirmation of bacterial strain. All the 10 isolates presumptively identified as bacteria amplified a fragment of 370 bp corresponding to the 16S rDNA gene. The enzymatic activity was expressed as an enzymatic index (EI), after 24 h of incubation. All isolate producers of amylase exhibited EI ≥ 2.0. The determination of the genetic profile and the clonal relationship among the isolates were performed by the method of ERIC-PCR polymorphism. The isolates of Bacillus spp were divided into 2 groups (I and II). Through this method, the discriminatory capacity of this analysis of polymorphisms was verified in differing producer strains from those not producing amylase.

Effect of inoculum age and physical parameters on in vitro culture of the entomopathogenic nematode Steinernema feltiae.

Entomopathogenic nematodes (EPNs) of the families Steinernematidae and Heterorhabditidae have a symbiotic association with bacteria which makes them virulent against insects. EPNs have been mass produced using in vivo and in vitro methods, including both solid and liquid fermentation. This study assessed the effect of nematode inoculum age on the production of Steinernema feltiae in liquid, solid and biphasic processes. Several physical parameters were also assessed: the effect of medium viscosity, flask size and aeration speed on the recovery and yield of infective juveniles (IJs). Inoculum age treatments included inoculum liquid cultures that were 7, 14, 21 and 28 days old. Nematodes from the same inoculum were added to one liquid medium (liquid culture), one solid medium with bacteria previously grown in sponge (solid culture) and a variation of the solid medium (a biphasic culture), in which the bacteria were first grown in liquid and, then, soaked into the sponges, with the purpose of providing a more homogeneous bacterial culture before nematode inoculation. Experiments were conducted in Erlenmeyer flasks. Eight treatments were established involving combinations of three variables: two media (with and without 0.2% agar), two flask sizes (250 and 150 ml) and two agitation speeds (180 and 280 rpm). The study showed increases in nematode yield for liquid cultures, but not for solid or biphasic cultures, with the advance of the inoculum age up to 28 days of growth. Furthermore, the addition of 0.2% agar to the liquid medium and increasing the aeration rate by using larger flasks with higher agitation speed may increase nematode recovery and final yield. The experiments were conducted using shake flasks but the results may also be applicable for bioreactors.

Combined effects of lactoferrin and lysozyme on Streptococcus pneumoniae killing.

Streptococcus pneumoniae is a common colonizer of the human nasopharynx, which can occasionally spread to sterile sites, causing diseases such as otitis media, sinusitis, pneumonia, meningitis and bacteremia. Human apolactoferrin (ALF) and lysozyme (LZ) are two important components of the mucosal innate immune system, exhibiting lytic effects against a wide range of microorganisms. Since they are found in similar niches of the host, it has been proposed that ALF and LZ could act synergistically in controlling bacterial spread throughout the mucosa. The combination of ALF and LZ has been shown to enhance killing of different pathogens in vitro, with ALF facilitating the latter action of LZ. The aim of the present work was to investigate the combined effects of ALF and LZ on S pneumoniae. Concomitant addition of ALF and LZ had a synergistic killing effect on one of the pneumococci tested. Furthermore, the combination of ALF and ALZ was more bactericidal than lysozyme alone in all pneumococcal strains. Pneumococcal surface protein A (PspA), an important vaccine candidate, partially protects pneumococci from ALF mediated killing, while antibodies against one PspA enhance killing of the homologous strain by ALF. However, the serological variability of this molecule could limit the effect of anti-PspA antibodies on different pneumococci. Therefore, we investigated the ability of anti-PspA antibodies to increase ALF-mediated killing of strains that express different PspAs, and found that antisera to the N-terminal region of PspA were able to increase pneumococcal lysis by ALF, independently of the sequence similarities between the molecule expressed on the bacterial surface and that used to produce the antibodies. LF binding to the pneumococcal surface was confirmed by flow cytometry, and found to be inhibited in presence of anti-PspA antibodies. On a whole, the results suggest a contribution of ALF and LZ to pneumococcal clearance, and confirm PspA's ability to interact with ALF.

Seasonal patterns of infestation by monogenean parasites of fish and their relationship with water parameters in two rivers with different disturbance gradients in southeastern Brazil.

Here, we evaluate the relationships between the infestation rates of five monogenean parasites species with the dry and wet seasons, with the organic and inorganic parameters of the water of two rivers: the Jacaré-Pepira and Jacaré-Guaçú, and with the condition factors of its fish hosts: Serrasalmus maculatus and Astronotus crassipinnis, in the state of São Paulo, southeastern Brazil. Fish were collected between January and December 2017. Anacanthorus serrasalmi, Amphithecium speirocamarotum and Gussevia asota had higher abundance rates (Student's t test, p ≤ 0.05) in the wet season. Gussevia asota had its abundance negatively correlated to nitrate in the Jacaré-Pepira River and with total nitrogen and potassium in the Jacaré-Guaçú River. Regarding the fish hosts condition factors, was observed a positive correlation with the abundances of G. asota in the Jacaré-Guaçú River, and with A. serrasalmi in the Jacaré-Pepira River. In general, wet season favored an increasing in the infestation rates of the monogeneans parasites in their host species, mainly in the river considered as the most polluted, the Jacaré-Guaçú River. Of the five parasites species analyzed in this study, only Gussevia astronoti and Rhinoxenus piranhus had no interaction with seasonality, river water variables, or fish host condition factors. On the other hand, G. asota had interactions both with water parameters (nitrate and total nitrogen) and with the hosts condition factors, which reflected in the abundance and intensity rates, showing itself as a species sensitive to changes in the environment and, therefore, that can be considered as a bioindicator organism.

Mechanical properties of asphalt binders evaluated by atomic force microscopy.

Atomic Force Microscopy was employed in order to relate the features observed on the surface of a 50/70 asphalt binder according to its local stiffness and elastic recovery. Indentations were performed in different points of the surface and a significant variation of elasticity was observed between the points on the so-called bee structure and the matrix. Also, indentations varying the maximum force were performed on similar white spots in the bee structure and the recovery was followed up to 1 h after indentation. It was observed that the elastic recovery is very much dependent on the colloidal structure of the bee. The final surface state of the binder, close to the bee for usual bees is not the same as the initial one indicating severe plastic deformation. Also, permanent phase change could be observed for bright spots presented in not well-structured bee arrangements. A surface hardening was observed in the bee region.

Scientific and popular health knowledge in the education work of community health agents in Rio de Janeiro shantytowns.

Health education for socially marginalized populations challenges the efficacy of existing strategies and methods, and the pertinence of the educational and philosophical principles that underpin them. The Brazilian Community Health Agents Initiative (CHAI) hires residents of deprived marginalized communities to undertake health promotion and education in their communities. The ultimate goal of the CHAI is to connect populations with the public healthcare system by promoting social re-affiliation, protecting civil rights and enhancing equity of access to health services. In this article, we present the education work of community health agents through interplay between popular and scientific health knowledge in nine Rio de Janeiro shantytowns. A critical ethnographic research design, using thematic analysis, allowed us to explore agents' education work to enhance family health literacy in shantytowns. Local culture and social practices inspire Agents to create original strategies to reconcile forms of health knowledge in their work.

Virulence of entomopathogenic nematodes and their symbiotic bacteria, under laboratory conditions, aiming controlling Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae) on sugarcane.

Sugarcane crops Saccharum spp. (Poales: Poaceae) produces different derivatives to the world: sugar, ethanol and bioenergy. Despite the application of pesticides, insect pests still cause economic losses, among these the pink sugarcane mealybug Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae) causing direct and indirect damage to the plant. This study assess the virulence of three entomopathogenic nematodes (EPNs) species and their symbiont bacteria against the pink sugarcane mealybug, under laboratory conditions. Fourteen treatments represented by control (distilled water), Heterorhabditis bacteriophora Poinar, 1976 (HB EN01) (Rhabditida: Heterorhabditidae), Steinernema rarum (Doucet, 1986) (PAM25) and Steinernema carpocapsae Weiser, 1955 (All) (Rhabditida: Steinermatidae) at concentrations of 25, 50, 75 and 100 infective juveniles (IJs)/insect, and the standard chemical product, thiamethoxam, were assayed. In a second experiment, the bacteria Photorhabdus luminescens (Thomas and Poinar, 1979), Xenorhabdus szentirmaii Lengyel, 2005 and Xenorhabdus nematophila (Poinar and Thomas, 1965) (Enterobacterales: Morganellaceae) at 3.0 x 109 cells/ml were assessed for each treatment. Ten replications were stablished, each one counting ten females/mealybugs inside a 10 cm Petri dish, amounting 100 individuals/treatment. All treatments were kept under stable conditions (25±1 ºC, H 70±10%, in the dark). All nematodes species infected S. sacchari. Steinerma rarum (PAM25) provided the highest mortality against the pink sugarcane mealybug (79.25%), followed by H. bacteriophora (HB EN01) (58.25%) and S. carpocapsae (All) (42.50%) (P<0.001). The mortality rate caused by X. szentirmaii, P. luminescens and X. nematophila were 40, 45 and 20%, respectively. Steinerma rarum (PAM25) has conditions to be a potential agent to be incorporate into the integrated pest management in sugarcane.

Histopathology of experimental myiasis in mice as a result of infestation and experimental implantation of Dermatobia hominis larvae.

A laboratory model of myiasis as a result of Dermatobia hominis (L.) larvae was developed using mice as hosts. Mice in three groups were each infested with one newly hatched larva and skin biopsies processed for histopathology at 4, 12, and 20 d postinfestation (dpi). Mice in three other groups were each subjected to implantation of one larva collected from an infested (donor) mouse at 4, 12, and 20 dpi. Skin lesions of these receptor mice were then assessed at 10, 14, and 6 d postimplantation (dpimp), respectively. The inflammatory process in infested mice at 4 dpi was discrete, consisting of a thin necrotic layer around the larva, edema, many neutrophils, few eosinophils, mast cells, and proliferation of fibroblasts. At 12 dpi, there was a thicker necrotic layer, edema, many neutrophils and eosinophils, few mast cells, neoformation of capillaries, proliferation of the endothelium and fibroblasts, and early stages of fibrosis. These histopathological characteristics together with fibrosis were observed over a large area of the lesion at 20 dpi. Mice submitted to larval implantations demonstrated similar skin histopathology to that seen in the infested rodents, 10 dpimp corresponding to 12 dpi and 6 or 14 dpimp to 20 dpi. In all mice, the progressive acute inflammatory process followed a sequence linked to factors such as size of larvae and presence of secretory-excretory products. Both infested mice and those implanted experimentally with D. hominis larvae were shown to be suitable models for the study of the parasite-host relationship in this important zoonotic myiasis.

Schistosoma mansoni: molecular characterization of Alkaline Phosphatase and expression patterns across life cycle stages.

Here we describe the cloning and characterization of the Schistosoma mansoni Alkaline Phosphatase (SmAP), previously identified in the tegument of adult worms. SmAP encodes a complete sequence composed of 536 amino acids containing an N-terminal signal peptide, five N-glycosylation sites, and a GPI anchor signal, similar to that described for mammalian orthologs. Real-time RT-PCR and Western blot experiments suggest a rapid translation as soon as cercariae are transformed into schistosomula. Immunolocalization analysis shows that the protein is widely distributed in the worm tissues, with increased concentration in the vitelline glands of female parasites. Furthermore, the surface localization of this enzyme was quantitatively supported by its enzymatic activity in live ex vivo or cultured parasites throughout the life cycle stages. The fact that cercariae accumulate large amounts of SmAP mRNA, which rapidly translates into protein upon schistosomula transformation, indicates it may have an important role in host invasion.

Characterization of edaphic fauna in different monocultures in Savanna of Piauí.

Vegetation cover may show diversity and composition patterns of the soil invertebrate community, as a function of litter quantity and quality in a specific habitat. The objective of this work was to characterize the distribution of edaphic fauna in different monocultures. The study was carried out at Chapada Grande farm in Regeneração, PI. Four monoculture areas were chosen: no-tillage soybean, eucalyptus, pasture, and a preserved native cerrado forest. Soil fauna was collected in a dry and wet period by pitfall traps containing 4% formaldehyde. The edaphic fauna was evaluated by the number of individuals per trap per day, average richness and richness, Shannon diversity index and Pielou uniformity index. Data were submitted to analysis of variance and multivariate Principal Component Analysis (PCA). The highest number of individuals per day trap and of average richness were registered in the pasture, eucalyptus and forest areas in both periods, while soybean showed lower values with predominance of Coleoptera and Formicidae groups. The pasture and forest areas showed of higher Shannon index values in the two evaluated seasons, probably due to higher contributions organic residues in the soil that favors the shelter, feeding and reproduction conditions. Regarding the Pielou index, the soybean system showed higher values in this variable. The Aranae, Coleoptera, Formicidae and Diptera groups predominated in the humid period, while Coleoptera and Formicidae predominated in the dry period. Systems that generate greater accumulation of residues harbor a greater diversity of invertebrates of the edaphic fauna. Seasonality had an effect on all variables analyzed and the wet period showed more expressive values.

High temperature AFM study of CAP 30/45 pen grade bitumen.

Bitumen is a complex mixture of hydrocarbons for which microstructural understanding is incomplete. In an effort to detail this microstructure, a asphalt cement sample (CAP 30/45) was analysed by thermal phase detection atomic force microscopy. Phase contrast and topography images showed that sample morphology is highly dependent on temperature. The 'bee structure' changed considerably at temperatures between 50 degrees C and 56 degrees C. A decrease of the oscillation amplitude was observed upon heating and the 'bees' completely disappeared at temperatures above 57 degrees C. When the temperature was decreased after melting at 170 degrees C, the 'bees' began to nucleate gradually at temperatures of 57 degrees C and its evolution with time was followed. Changes in morphology were compared to thermal analysis results and a model for the 'bee' structure was proposed.

Immunization with SmIg, a novel tegument protein from Schistosoma mansoni, fails to induce protection in mice but reduces liver pathology.

Proteins associated with the schistosome tegument are of great importance for the development of new intervention strategies since they may be exposed on the surface of the parasite. Herein, we have isolated a cDNA clone encoding for the Schistosoma mansoni SmIg and its recombinant protein was tested as a potential vaccine candidate. Initially, its amino acid sequence was analysed by bioinformatics and shown to possess an N-terminal signal peptide, a C-terminal transmembrane helix, 4 glycosylation sites, an immunoglobulin conserved domain and 73% similarity with a hypothetical S. japonicum protein of unknown function. SmIg was produced by E. coli as a recombinant protein (rSmIg) and its protective effectiveness was evaluated against S. mansoni infection with 100 cercariae in a murine model. Mice immunized with rSmIg induced an immune response characterized by dominant IgG1 isotype and significant levels of IFN-gamma, TNF-alpha, IL-10 and IL-4. Although immunogenic, the recombinant vaccine failed to induce worm burden reduction when compared to the infected control group. However, rSmIg-immunized mice had significant reductions of liver granuloma volume and fibrosis content by 31.8% and 49%, respectively. In conclusion, SmIg is a new tegument protein from S. mansoni that plays an important role in reducing pathology induced by parasite infection.

Dietary calcium, dairy food intake and metabolic abnormalities in HIV-infected individuals.

BACKGROUND: Epidemiological data suggest that calcium intake may influence lipid metabolism. It is unknown whether this influence also occurs in individuals with HIV/AIDS. The present study aimed to assess the relationship between dietary calcium, dairy food intake and metabolic parameters in individuals with HIV/AIDS. METHODS: A cross-sectional study was conducted with 100 individuals with HIV/AIDS. Calcium intakes and food group consumption were determined by a food 24-h dietary recall and a food frequency questionnaire, respectively. The level of physical activity was determined with the international physical activity questionnaire and metabolic syndrome (MS) was defined by National Cholesterol Education Program Adult Treatment Panel III (2001). Student's t-test, one-way analysis of variance and chi-square were used to compare the groups. RESULTS: The mean (SD) calcium intake was 559.5 (298.84) mg day(-1) and dairy food consumption was 1.73 (0.78) servings per day. Dietary calcium intake below 700 mg day(-1) had greater waist circumference, body mass index (BMI) but not significant and higher systolic blood pressure (SBP) (P < 0.05) and diastolic blood pressure (DBP) (P = 0.07). Dairy food consumers (>2 servings per day) showed lower BMI (P < 0.01), waist circumference (P = 0.05), SBP and DBP (P < 0.05). There was a significant association between calcium intake, MS and hypertension. The odds ratio for MS was 2.0 [95% confidence interval (CI) = 1.23-3.32] and for hypertension was 2.25 (95% CI = 1.44-4.44). Only 21% of the individuals were categorised in the moderate/intense physical activity level. CONCLUSIONS: The results obtained suggest that a dietary pattern with higher proportion of calcium and fruits/vegetables may protect against abdominal obesity and hypertension in HIV-infected individuals.

The long search for a serotype independent pneumococcal vaccine.

Introduction: Serotype replacement - a consequence of polysaccharide vaccine use - will continue to drive the inclusion of new serotypes on conjugate vaccines, increasing production complexity and costs, and making an already expensive vaccine less accessible to developing countries, where prevalence is higher and resources available for health systems, scarcer. Serotype-independent formulations are a promising option, but so far they have not been successful in reducing colonization/transmission.Areas covered: Protein-based and whole-cell vaccine candidates studied in the past 30 years. Challenges for serotype-independent vaccine development and alternative approaches.Expert opinion: Clinical trials performed so far demonstrated the importance to establish more reliable animal models and better correlates of protection. Defining appropriate endpoints for clinical trials of serotype-independent vaccine candidates has been a challenge. Inhibition of colonization has been evaluated, but concern on the extent of bacterial elimination is still a matter of debate. Challenges on establishing representative sites for clinical trials, sample sizes and appropriate age groups are discussed. On a whole, although many challenges will have to be overcome, establishing protein-based antigens as serotype-independent vaccines is still the best alternative against the huge burden of pneumococcal diseases in the world.

Current locoregional therapies and treatment strategies in hepatocellular carcinoma.

Locoregional therapies (lrts) play an important role in the treatment of hepatocellular carcinoma (hcc), with the aim of increasing overall survival while preserving liver function. Various forms of lrt are available, and choosing the best one depends on technical aspects, liver morphology, tumour biology, and the patient's symptoms. The purpose of the present review article is to provide an overview of the current evidence relating to the use of percutaneous ablation, transarterial chemoembolization, and transarterial radioembolization for the curative or palliative treatment of hcc. Special situations are also reviewed, including the combined use of systemic therapy and lrt, indications and techniques for bridging to transplant and downstaging, and the use of lrt to treat patients with hcc and macrovascular invasion.