RESUMO
Mulberry is a plant belonging to the family Moraceae, and genus Morus. Allergic sensitization to mulberries has been reported as both food allergy or respiratory allergy, and cross-reactivity between mulberries and other pollens or fruits was described. Clinically, in the articles reporting mulberry allergy, the reactions included respiratory allergy, airborne contact urticaria, anaphylaxis, oral allergy syndrome, and food induced urticaria. As far as cross-reactivity is concerned, the allergens identified thus far in mulberries include pathogenesis-related (PR)10 proteins, with sequence identity to Bet v 1 from birch, lipid transfer (LTP)1 proteins with identity with LTPs from Rosaceae family plants, panallergens groups, and also ubiquitin-like protein and cystatin-like protein. The two latter proteins account for cross-reactions with Parietaria judaica and Olea europaea. Such large cross-reactivity warrants to pay particular attention to the risk of systemic reactions to foods, particularly in subjects sensitized to birch, parietaria or olive pollens. In fact, the increasing use of mulberry as a food product, which is encouraged by its remarkable antioxidant power, expose sensitized patients to possible reactions after ingesting foods, dietary supplements or nutraceuticals containing mulberry. Mulberry allergenicity can vary according to the processing methods used since some allergens are thermostable and other loss their reactivity during heating.
RESUMO
The chemical structure-dynamics relationship for poly(trimethylene 2,5-furanoate) and poly(trimethylene 1,4-cyclohexanedicarboxylate) was investigated via dielectric spectroscopy and compared with that of poly(trimethylene terephthalate) in order to evaluate the impact on the subglass dynamics of the chemical nature of the ring. Further comparison was accomplished with the neopentyl glycol containing counterparts: poly(neopentyl 2,5-furanoate) and poly(neopentyl 1,4-cyclohexanedicarboxylate). Our study reveals a multimodal nature of the subglass ß process. For the more flexible polymers (containing cyclohexane rings) three modes for the ß process were detected. The faster mode was assigned to the relaxation of the oxygen linked to the aliphatic carbon, the slower one to the link between the aliphatic ring and the ester group, and the third mode to the aliphatic ring. For stiffer polymers (containing aromatic rings), the local modes appear more coupled. This effect is more evident in the polymers with the furan ring where essentially a single ß mode can be resolved.
RESUMO
The computational study of chemical reactions in complex, wet environments is critical for applications in many fields. It is often essential to study chemical reactions in the presence of applied electrochemical potentials, taking into account the non-trivial electrostatic screening coming from the solvent and the electrolytes. As a consequence, the electrostatic potential has to be found by solving the generalized Poisson and the Poisson-Boltzmann equations for neutral and ionic solutions, respectively. In the present work, solvers for both problems have been developed. A preconditioned conjugate gradient method has been implemented for the solution of the generalized Poisson equation and the linear regime of the Poisson-Boltzmann, allowing to solve iteratively the minimization problem with some ten iterations of the ordinary Poisson equation solver. In addition, a self-consistent procedure enables us to solve the non-linear Poisson-Boltzmann problem. Both solvers exhibit very high accuracy and parallel efficiency and allow for the treatment of periodic, free, and slab boundary conditions. The solver has been integrated into the BigDFT and Quantum-ESPRESSO electronic-structure packages and will be released as an independent program, suitable for integration in other codes.
RESUMO
AIMS: This study focused on the influence of different amounts of NaCl in the medium in Vibrio anguillarum EmpA protease production at both the transcriptional and post-transcriptional levels. METHODS AND RESULTS: Vibrio anguillarum 975/I was cultivated in cM9 medium with varying concentrations of NaCl: 0·5, 1·5, 3·0%. EmpA protease was monitored in the supernatants by the skim milk test, azocasein assay and Western blot analysis. The empA gene expression was measured by real-time PCR. A mutant strain 975/I defective for the empA gene confirmed the specificity of the response for EmpA protease. Active protease production was induced by 0·5 and 1·5% NaCl-amended media; however, the strain cultivated in 3·0% NaCl was unable to secrete EmpA protease. The quantitative expression of the empA gene was very similar in all tested conditions. CONCLUSIONS: The NaCl concentration in the medium modulates the secretion of active EmpA protease in V. anguillarum at a post-transcriptional level. SIGNIFICANCE AND IMPACT OF THE STUDY: EmpA protease is one of the most important virulence factors in V. anguillarum. We demonstrated the influence of osmotic changes in the regulation of EmpA protease in the V. anguillarum 975/I strain. This finding has an important impact on the evaluation of factors determining the onset of disease in fish.
Assuntos
Proteínas de Bactérias , Meios de Cultura/química , Metaloproteases , Cloreto de Sódio/farmacologia , Vibrio/efeitos dos fármacos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Metaloproteases/genética , Metaloproteases/metabolismo , Vibrio/genética , Vibrio/metabolismoRESUMO
In this study, we aimed to understand whether abiotic factors affect the expression of virulence genes in Vibrio anguillarum. We observed the in vitro responses of two Mediterranean strains of V. anguillarum to temperature, NaCl and iron concentration changes. We monitored growth performance and gene transcription levels by comparing the results obtained under stressed conditions (temperatures of 5 °C, 15 °C and 37 °C; NaCl concentrations of 3% and 5%; and iron depletion and excess) with those obtained under standard growth conditions (25 °C, 1.5% NaCl and 0.6 µm of iron). The results showed that the strains respond differently. The strain 975/I was most strongly affected by conditions of 15 °C and iron depletion; these conditions induced increased transcription levels of empA, angR and fatA. Growth of the strain 17/I was inhibited at 15 °C and in iron depletion conditions; this strain also showed dramatic changes in the transcription levels of toxR and tonB2 under increased NaCl concentrations. These results demonstrate that environmental stress affects the expression of virulence genes in V. anguillarum that have implications for the competitiveness, stress tolerance and the ability of V. anguillarum to cause infection.
Assuntos
Proteínas de Bactérias/genética , Doenças dos Peixes/microbiologia , Regulação Bacteriana da Expressão Gênica , Vibrioses/veterinária , Vibrio/fisiologia , Vibrio/patogenicidade , Animais , Proteínas de Bactérias/metabolismo , Deficiências de Ferro , Dados de Sequência Molecular , Pressão Osmótica , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Análise de Sequência de DNA/veterinária , Temperatura , Vibrio/genética , Vibrioses/microbiologia , Virulência/genéticaRESUMO
An experiment was carried out in red porgy, Pagrus pagrus (Teleostei, Sparidae), to assess the effects of a 14-day fasting period, followed by refeeding to apparent satiation, on the contents of digestive enzymes (total proteases, and particularly pepsin, trypsin, chymotrypsin, carboxypeptidases A and B; amylase and lipase). Two fish groups were considered: one (indicated as fasted/refed group) was fasted for 14 days and then refed during further 7 and 15 days, and the other was fed throughout the study and was taken as a control group. The measured enzymatic values showed that fasting resulted in a generalized, not significant decrease, of the activity of digestive enzymes. Refeeding caused a significant increase for most of the assayed enzymes: total proteases both in the middle and distal intestine, pepsin in the stomach, trypsin in the middle intestine, and amylase and lipase in the proximal intestine. Nevertheless, the detection in the fasted/refed fish of enzymatic values still lower than those measured in the control fish suggested that fish experiencing short-term fasting were partially impaired in their digestive capacity.
Assuntos
Digestão/fisiologia , Ingestão de Alimentos/fisiologia , Enzimas/metabolismo , Jejum/metabolismo , Perciformes/metabolismo , Análise de Variância , Animais , Aquicultura/métodos , Concentração de Íons de Hidrogênio , Intestinos/enzimologia , Sicília , Estômago/enzimologiaRESUMO
The structural stability of fcc Ni over a very large pressure range offers a unique opportunity to experimentally investigate how magnetism is modified by simple compression. K-edge x-ray magnetic circular dichroism (XMCD) shows that fcc Ni is ferromagnetic up to 200 GPa, contradicting recent predictions of an abrupt transition to a paramagnetic state at 160 GPa. Density functional theory calculations point out that the pressure evolution of the K-edge XMCD closely follows that of the p projected orbital moment rather than that of the total spin moment. The disappearance of magnetism in Ni is predicted to occur above 400 GPa.
RESUMO
The present research reports the first description of Shell Disease Syndrome in European spiny lobsters Palinurus elephas (Fabricius 1787), which occurred in an experimental aquaculture facility in Sicily (Italy). Both bacterial characterization and histopathological examination of the exoskeleton at site of lesions was carried out. Infected specimens showed tail fan erosions, and in one case uropod ulceration and complete loss of periods. Identified species included: Listonella anguillarum 50.5%, Vibrio parahaemolyticus 27.5% and Vibrio alginolyticus 22%. Microscopic evaluation of lesions indicate the presence of inflammatory responses, which include melanization and pseudomembrane formation, similar to those described for other crustaceans affected by SDS.
Assuntos
Estruturas Animais/microbiologia , Quitina/metabolismo , Listonella/patogenicidade , Palinuridae/microbiologia , Vibrioses/veterinária , Vibrio alginolyticus/patogenicidade , Estruturas Animais/patologia , Animais , Aquicultura , Listonella/isolamento & purificação , Palinuridae/metabolismo , Síndrome , Vibrioses/microbiologia , Vibrioses/patologia , Vibrio alginolyticus/isolamento & purificaçãoRESUMO
The physiological effects of short-term starvation on some haematological, biochemical and non-specific immune response parameters together with the histological structure of the skin, were investigated in the European eel, Anguilla anguilla. Blood haemoglobin and haematocrit, serum glucose and cortisol, hemolysins, haemagglutinins, and lysozyme in the plasma, kidney and epidermal extract, were measured in fish after 31, 42 and 58 days of starvation, and compared to those of fed fish. Starvation did not affect haemoglobin and haematocrit values, while an increase in glucose and cortisol levels was found in starved eels by day 42. Haemolytic and haemagglutinating activities decreased in starved eels. On the other hand, starvation caused an increase in the lysozyme content in the epidermal extracts, while no significant variations were observed in kidney and plasma. On the whole, no major changes in metabolic, haematological and non-specific immune parameters were observed when short-term (less than 2 months) starvation was applied to the European eel, suggesting an adaptive response to starvation, rather than a typical alarm-stress response, allowing this species to withstand food deprivation.
Assuntos
Anguilla/fisiologia , Fenômenos Fisiológicos da Pele , Inanição/veterinária , Adaptação Fisiológica/fisiologia , Anguilla/sangue , Anguilla/imunologia , Animais , Análise Química do Sangue , Tamanho Corporal , Pele/citologia , Fenômenos Fisiológicos da Pele/imunologia , Inanição/sangue , Inanição/imunologia , Fatores de TempoRESUMO
BACKGROUND: Erythropoietin (EPO), the main haematopoietic growth factor for the proliferation and differentiation of erythroid progenitor cells, is also known for its angiogenic and regenerative properties. MATERIALS AND METHODS: In this study, we aimed to test the regenerative effects of EPO administration in an experimental model of Sea bass (Dicentrarchus labrax) subjected to amputation of the caudal fin. RESULTS: Erythropoietin-treated fishes (3000 UI of human recombinant EPO-alpha immediately after cutting and after 15 days) showed an increased growth rate of their fins compared with those untreated (anova variance: P: 0.01 vs. P: 0.04). By analysing fin length at established times (15 and 30 days after cut), EPO-treated fishes always showed an increased length compared with untreated ones (T-15: 1.1 +/- 0.2 vs. 0.7 +/- 0.2 cm, P: 0.03; T-30: 1.9 +/- 0.3 vs. 1.2 +/- 0.2 cm, P: 0.01). Moreover, exogenous EPO administration induced an enormous increase in EPO-blood levels at each observation time (T-15: 2240 +/- 210 vs. 16.7 +/- 1.8 mU mL(-1), P < 0.001; T-30: 2340 +/- 190 vs. 17.1 +/- 1.9 mU mL(-1), P < 0.001), whereas these levels remained quite unmodified in untreated fishes. Immunochemical analyses performed by confocal laser scanning microscopic observations showed an increased expression of EPO-receptors and PECAM-1 (an endothelial surface marker of vessels sprout) in the regenerating tissue, whereas no signs of inflammation or fibrosis were recognisable. CONCLUSIONS: All these findings confirm EPO as a new factor involved in regenerative processes, also suggesting a potential, future utility for new therapeutical applications in the field of human regenerative medicine.
Assuntos
Eritropoetina/metabolismo , Peixes , Neovascularização Fisiológica/fisiologia , Regeneração/fisiologia , Animais , Bass , Eritropoetina/genética , Imuno-Histoquímica , Modelos Biológicos , Neovascularização Fisiológica/genética , Regeneração/genética , Medicina RegenerativaRESUMO
Field and laboratory studies were conducted to evaluate the intestinal responses to partial replacement of fish meal with rice protein concentrate (RPC) in practical diets for blackspot seabream Pagellus bogaraveo. Two experimental diets were formulated to be isoproteic and isoenergetic with an increasing level of RPC (20 and 35%, respectively) and were tested against a fish meal-based control diet (RPC0). The diets showed similar features for growth performances and both intestinal histology and digestive enzymes. This study confirmed that RPC does not induce intestinal mucosa alterations in this fish. The dietary RPC supplement caused a significant increase in trypsin activity, whereas lipase activity was reduced.
Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas Alimentares/metabolismo , Pesqueiros/métodos , Oryza/metabolismo , Dourada/fisiologia , Animais , Digestão/fisiologia , Fezes/química , Intestinos/citologia , Intestinos/enzimologia , Lipase/metabolismo , Músculo Esquelético/química , Tripsina/metabolismoRESUMO
AIMS: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. METHODS AND RESULTS: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10(8) cell ml(-1) of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. CONCLUSIONS: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.
Assuntos
Bactérias/metabolismo , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/crescimento & desenvolvimento , Benzeno/metabolismo , Derivados de Benzeno/metabolismo , Biodegradação Ambiental , Contagem de Colônia Microbiana/métodos , Respiração , Tolueno/metabolismo , Xilenos/metabolismoRESUMO
The present study is focused on assessing the growth and hydrocarbon-degrading capability of the psychrophilic strain Oleispira antarctica RB-8(T). This study considered six hydrocarbon mixtures that were tested for 22days at two different cultivation temperatures (4 and 15°C). During the incubation period, six sub-aliquots of each culture at different times were processed for total bacterial abundance and GC-FID (gas chromatography-flame ionization detection) hydrocarbon analysis. Results from DNA extraction and DAPI (4',6-diamidino-2-phenylindole) staining showed a linear increase during the first 18days of the experiment in almost all the substrates used; both techniques showed a good match, but the difference in values obtained was approximately one order of magnitude. GC-FID results revealed a substantial hydrocarbon degradation rate in almost all hydrocarbon sources and in particular at 15°C rather than 4°C (for commercial oil engine, oily waste, fuel jet, and crude oil). A more efficient degradation was observed in cultures grown with diesel and bilge water at 4°C.
Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias/classificação , Bactérias/genética , Óleos , Petróleo/metabolismoRESUMO
Repeated bleomycin administration in animals and humans produces significant lung fibrosis. The pathogenesis of this toxicity may be multifactorial, but it appears to be initiated through the production of radical oxygen species by an activated bleomycin-iron-oxygen ternary complex. Protection of lung tissue from bleomycin-induced toxicity may occur through both specific metabolic inactivation of bleomycin by the enzyme bleomycin hydrolase, as well as by such non-specific antioxidants as catalase and the glutathione system. The effect of chronic, systemic administration of bleomycin on the activities and levels of these enzymes and proteins in pulmonary tissue is unknown. C57BL/6 mice were injected subcutaneously with saline, non-fibrogenic (2 mg/kg) and fibrogenic (10 mg/kg) doses of bleomycin twice-weekly for 6 weeks. Animals were killed at 0, 1.5, 3, and 6 weeks after initiation of bleomycin treatment. Catalase activity was increased more than 50% at 3 weeks in the low-dose animals, and was decreased over 40% at 6 weeks in the high-dose animals. Total lung glutathione levels were unaffected in both groups, although glutathione reductase activity was increased significantly (over 2-fold) at 1.5 and 3 weeks in the high-dose animals. At 6 weeks glutathione reductase was increased 7- and 12-fold in low and high-dose animals respectively. Glutathione peroxidase activity also was elevated more than 2-fold above control values at 6 weeks in both sets of animals. There was no evidence of induction of bleomycin hydrolase activity at any time point. Rather, bleomycin hydrolase activity was decreased significantly to 30 and 40% of control values at 3 and 6 weeks, respectively, in mice receiving the fibrogenic doses of bleomycin. These results demonstrate that chronic, systemic administration of non-fibrogenic and fibrogenic doses of bleomycin produces changes in activity of lung antioxidant defense mechanisms. The early loss of lung bleomycin hydrolase activity may contribute to the pathogenesis of bleomycin-induced pulmonary toxicity following repeated drug exposure.
Assuntos
Bleomicina/toxicidade , Cisteína Endopeptidases , Pulmão/efeitos dos fármacos , Animais , Antioxidantes , Catalase/análise , Feminino , Glutationa Peroxidase/análise , Glutationa Redutase/análise , Glicosídeo Hidrolases/análise , Pulmão/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamenteRESUMO
Scanning and transmission electron microscopy were used to investigate the fine structure of the sperm of the Sparid fish Pagellus erythrinus L. The spermatozoon of pandora has a spherical head lacking an acrosome, a cone-shaped midpiece and a long tail. The midpiece houses a single mitochondrion. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole which are arranged at right angles to each other. The flagellum is inserted medio-laterally into the head, contains the conventional 9+2 axoneme and possesses one pair of lateral fins. On the basis of its ultrastructural organization, the pandora sperm can be regarded as an evolved form of the primitive spermatozoon found in Teleosts. According to the morphological classification proposed by Mattei (1970), the sperm of pandora belongs to a "type I" designation, like that of the other Sparid fish.
Assuntos
Perciformes/anatomia & histologia , Espermatozoides/ultraestrutura , Animais , Evolução Biológica , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Mitocôndrias/ultraestrutura , Perciformes/classificação , Cabeça do Espermatozoide/ultraestrutura , Peça Intermédia do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/ultraestruturaRESUMO
Previously, our laboratory reported an existing relationship between ontogenesis of heterophil activity and susceptibility to Salmonella enteritidis infection in poultry during the first week post-hatch. The prophylactic administration of S. enteritidis-immune lymphokines has been shown to enhance heterophil function in vitro and reduce S. enteritidis organ invasion in 1-day-old chicks. However, how long the heterophils remain activated is currently unknown. The objective of this research was to evaluate the duration of enhanced heterophil phagocytosis of S. enteritidis following the prophylactic administration of a single injection of S. enteritidis-immune lymphokines to neonatal chicks. Administration of S. enteritidis-immune lymphokines on the day of hatch resulted in a significant increase in heterophil phagocytic activity (P < 0.05) through day 5 post-hatch. No significant differences in phagocytic activities of heterophils from control and S. enteritidis-immune lymphokinetreated chicks was demonstrated from day 6 to 14 post-hatch. These data suggest that the administration of S. enteritidis-immune lymphokines on day of hatch potentiates heterophil phagocytic activity during a critical period of susceptibility to Salmonella infection in neonatal chicks. The immune lymphokine-induced enhancement of heterophil activity subsides by day 5 as the chick's natural defenses mature and are able to resist infections without exogenous augmentation.
RESUMO
During the first week post-hatch, chickens demonstrate an increased susceptibility to infection by bacteria such as Salmonella. The purpose of the present study was to evaluate the effects of immune lymphokines on phagocytosis and killing activities of heterophils in chicks during the first 1-7 days of life. Lymphokines isolated from chicken splenic T-cells harvested from Salmonella enteriditis (SE)-hyperimmunized hens (SE-ILK), have in past experiments, demonstrated augmentation of heterophil activity in day-of-hatch chicks resulting in protection from SE organ invasion. The present experiments reveal significant increases (p<0.05) in heterophil phagocytosis and killing when comparing chicks treated with SE-ILK to control groups in vitro. In SE-ILK-treated groups, a two-fold or greater increase is noted in heterophil phagocytosis within I h of incubation as compared to controls. Heterophils isolated from 1-day-old and 4-day-old chicks treated with SE-ILK killed significantly greater numbers (p<0.05) of SE than heterophils isolated from control groups. By Day 7 post-hatch, significance is not noted in the killing activity of heterophils from treated groups when compared to control groups. However, heterophils from SE-ILK groups continue to kill greater numbers of SE than control groups. These data support SE-ILK augmentation results in an enhanced heterophil function in chicks during the greatest period of susceptibility to Salmonella invasion.
Assuntos
Galinhas , Granulócitos/imunologia , Linfocinas/imunologia , Doenças das Aves Domésticas/imunologia , Salmonelose Animal/imunologia , Salmonella enteritidis/imunologia , Animais , Feminino , Imunização/veterinária , Masculino , Fagocitose/imunologia , Doenças das Aves Domésticas/microbiologia , Baço/imunologia , Linfócitos T/imunologiaRESUMO
The data from 55 patients with empty sellae seen during the past five years are examined. The clinical and radiological features most helpful in defining and classifying each case are identified. The most frequent and most serious complications and the warning signs useful in diagnosis are discussed. The indications for and the results of surgical treatment are reviewed.
Assuntos
Síndrome da Sela Vazia/patologia , Adolescente , Adulto , Rinorreia de Líquido Cefalorraquidiano/etiologia , Síndrome da Sela Vazia/complicações , Síndrome da Sela Vazia/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/etiologia , Doenças da Hipófise/etiologia , Radiografia , Neuralgia do Trigêmeo/etiologiaRESUMO
The study of pituitary diseases is described, with visualization of the cavernous and intercavernous sinuses accomplished through percutaneous, transfemoral catheterization, using special methods to ensure its reliability. The most characteristic normal and pathological findings are described. The value of this method and the indications for its use in diagnosis are discussed. The possibility of combining morphological investigations with regional functional studies of pituitary hormones by selective blood sampling is suggested. This technical development opens new prospects for the future and further broadens the indications for use of this procedure.
Assuntos
Cavidades Cranianas/diagnóstico por imagem , Flebografia/métodos , Doenças da Hipófise/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Seio Cavernoso/diagnóstico por imagem , Humanos , Neoplasias Hipofisárias/diagnóstico por imagemRESUMO
Two variations on the currently most commonly used technical method for phlebography are described. The first variation involves an original method for visualizing the dorsolumbosacral epidural plexus via the retrograde route from the azygos vein. If necessary this can be associated with catheterization and simultaneous injection into an ascending lumbar vein or into a lateral sacral vein. This method permits exploration from T7 to S1 and provides phlebograms of excellent quality, owing to the reduction in the flow caused by countercurrent injection. The second variation involves visualizing the epidural venous plexus by means of double percutaneous transfemoral catheterization of the hypogastric veins, using balloon catheters. This method is performed easily and rapidly. Preferential flow is obtained via the epidural plexus, and there is less diversion of the contrast medium through anastomoses and less filling of the vena cava. The specific indications for these methods are described. The availability of alternative methods beyond the traditional one renders epidural phlebography more reliable and more manageable, and it ensures certainty of diagnosis.