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Holm oak trees (Quercus ilex L.) mortality is increasing worryingly in the Mediterranean area in the last years. To a large degree this mortality is caused by the oomycete Phytophthora spp., which is responsible for forest decline and dieback in evergreen oak forest areas of the southwestern Iberian Peninsula. This study is based on the possibility of applying chemical elicitors or filtered oomycete extracts to holm oak somatic embryos (SE) in order to induce epigenetic memory, priming, that may increase tolerance to the pathogen in future infections. To this end, we first examined the effect of priming treatments on SE development and its oxidative stress state, to avoid elicitors that may cause damage to embryogenic tissues. Both, the sterile oomycete extracts and the chemical elicitor methyl jasmonate (MeJA) did not produce any detrimental effect on SE growth and development, unlike the elicitors benzothiadiazole (BTH) and p-aminobenzoic acid (PABA) that reduced the relative weight gain and resulted in necrotic and deformed SE when were applied at high concentrations (25 µM BTH or 50 µM PABA) in accordance with their high malondialdehyde content. No significant differences among elicitation treatments were found in dual culture bioassays, although those SEs elicited with 50 µM MeJA increased H2O2 production after challenged against active oomycete indicating the activation of stress response. Since this elicitation treatment did not produce any adverse effect in the embryogenic process we suggest that could be used in further priming experiments to produce holm oak plants adapted to biotic stress.

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OBJECTIVES: The authors sought to check the frequency of biliary complications with the use of a T-tube. In 2012, throughout the year, it was carried out systematically in all liver transplantations regardless of the characteristics of the bile duct. Despite the long experience, biliary complications remain a common cause of postoperative morbidity and mortality. MATERIAL AND METHODS: In this study we compared complications in 23 consecutive transplantation cases using T-tube biliary anastomosis during the year 2012 with 23 consecutive transplantation cases without T-tube during the year 2013. We evaluated postoperative complications and long-term outcomes (for 2 years to 3 years). RESULTS: Of the 23 patients with anastomosis with a T-tube, 2 patients (8.69%) had biliary stricture that required prosthesis by endoscopic retrograde cholangiopancreatography, 1 of them (4.34%) was operated by incorrect placement of the T-tube, and in 4 patients (17.39%) bile leakage (endoscopic retrograde cholangiopancreatography prostheses in 3 cases and hepaticojejunostomy in 1). During follow-up at 3 years, only 2 patients had minimal bile duct dilatation without clinical relevance. In the patients who underwent transplantation without a T-tube, 18 (78.26%) had no complications, 3 (13.04%) showed stenosis (prosthesis placement), and 2 (8.69%) had bile leakage (hepaticojejunostomy and prosthesis). During follow-up at 2 years to 3 years, no patient had biliary dilatation or alteration of cholestatic parameters. In the comparative study of both groups we found no statistically significant differences. CONCLUSIONS: We have not seen an improvement in complications with the use of T-tube (69.56% vs. 78.23%) that encourage us to work systematically, although the small number of cases does not allow statistically significant conclusions.

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OBJECTIVES: The authors sought to identify strictures or hepatic artery obstruction with posterior collateral transformation in our series of liver transplantation, treatment, and evolution. The thrombosis or severe hepatic artery stenosis sometimes presents a compensation mechanism, the collateral transformation of the artery. MATERIAL AND METHODS: From April 2002 to December 2011 we collected 18 cases of collateral transformation. We analyzed data regarding the transplantation, diagnosis, treatment, clinical evolution, liver function, and Doppler-ultrasound. RESULTS: The main indication was alcoholic cirrhosis, followed by hepatocellular carcinoma - hepatitis C virus. The mean cold ischemia time was 292.2 minutes mean hot ischemia was 48.8. The anastomosis was performed on the gastroduodenal-splenic patch donor in 14 cases, the celiac trunk in 2 cases, and on grafts to the aorta in another 2. Doppler ultrasound showed 8 cases without complications, 8 with low flows, and 2 cases with alterations of the right hepatic artery. Computed tomographic (CT) angiography was performed in patients with impaired eco-Doppler and found 4 obstructions, 2 cases with kinking, 1 stenosis, and 3 normal cases. Three patients with low flows were re-operated and another re-transplanted. After diagnosis of collateral transformation, all were treated with antiplatelet agents. Two cases of angioplasty were associated. The collaterals were diagnosed 1 month to 44.8 months after transplantation. Five patients died. In the latest data, 10 patients do not have analytical alteration. The Doppler ultrasound shows 7 cases being normal and 6 with flow but low resistances. CONCLUSIONS: In our series, all patients with collateral transformation, except one who was transplanted, maintain good liver function with permeable vessels.

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Introducción: la reacción inflamatoria (RI) es una secuencia compleja de acontecimientos que ocurren en los tejidos de los seres vivos luego de lesión celular. Se puede manifestar objetivamente para el cirujano mediante la presencia de hallazgos macroscópicos abdominales observados durante la cirugía (1,2,3). El objetivo del presente estudio fue evidenciar la reacción inflamatoria en el abdomen de la rata expuesta a: bilis, clips de titanio y fragmentos de gasa. Material y métodos: se realizó un modelo experimental en el Laboratorio de Cirugía de la Universidad Francisco Marroquín. Se utilizaron 100 ratas de la especie Wistar a las cuales les fueron asignadas en forma aleatoria cifras numéricas para clacificarlas así...

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A protocol based on SAAT (sonication-assisted Agrobacterium-mediated transformation) has been developed to obtain herbicide-resistant transgenic black locust (Robinia pseudoacacia L.) plants. Cotyledon explants were co-cultivated with Agrobacterium AGL1 strain carrying the pTAB16 plasmid (bar and gusA genes). The effects of bacterial concentration (OD550 of 0.3, 0.6, 0.8) and method of infection (sonication vs immersion) on bacterial delivery were determined by assaying cotyledons for transient beta-glucuronidase expression 3 days after infection. SAAT increases transient expression efficiency especially at an OD550 of 0.6. After determining bacterial concentration and infection method, other factors affecting transformation efficiency, such as explant preconditioning and period of time before applying selection, were tested. From these experiments, the preferred protocol for black locust cotyledon transformation should include sonication of preconditioned cotyledons in AGL1 suspension, coculture for 3 days with 100 microM acetosyringone and transfer to selection medium with 4 mg/l phosphinothricin and 150 mg/l timentin. Of the initial explants, 2% produced at least one transgenic shoot. Genetic transformation was confirmed by Southern hybridization, chlorophenol red assay and herbicide tolerance of the regenerated plants.

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Shoot-tips from several genotypes of the cardenolide-producing perennial shrub Digitalis obscura L. were successfully cryopreserved using the encapsulation-dehydration technique. Precultivation on MS medium containing 0.5 M sucrose, followed by 2.5 h dehydration (final weight 30 %) induced shoot regrowth in 42 % of cryopreserved shoot-tips. Cold-hardening of the in vitro cultures before sucrose treatment dramatically increased shoot recovery up to 86 %. The optimized cryopreservation protocol was then employed using different shoot cultures from five D. obscura genotypes. Responses to cryopreservation depended mainly on the genotype, best results being obtained when shoot tips from HU3 and LL11 were used. Prolonged subcultures reduced proliferation rates in both control and cryopreserved HU3 shoot-tips, whereas long-term storage in LN did not affect the shoot recovery rate of the genotype. RAPD markers were employed to evaluate possible somaclonal variation occurring in shoots regenerated through successive subcultures and after cryopreservation. The band patterns revealed differences between the original parent plant and the shoots grown in vitro, especially after a prolonged subculture (84.9 % of matches for HU3 after 16 subcultures vs. 93.4 % for AY3 after 2 subcultures). Nevertheless, match percentages were higher (98.6 % to 99.5 %) when band patterns from subcultured shoots were compared to those obtained from their respective control or frozen progenies indicating that cryopreservation ensure genetic stability of selected Digitalis obscura genotypes.

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Overexpression of the HAL1 gene in yeast has a positive effect on salt tolerance by maintaining a high internal K(+) concentration and decreasing intracellular Na(+) during salt stress. In the present work, the yeast gene HAL1 was introduced into tomato (Lycopersicon esculentum Mill.) by Agrobacterium tumefaciens-mediated transformation. A sample of primary transformants was self-pollinated, and progeny from both transformed and non-transformed plants (controls) were evaluated for salt tolerance in vitro and in vivo. Results from different tests indicated a higher level of salt tolerance in the progeny of two different transgenic plants bearing four copies or one copy of the HAL1 gene. In addition, measurement of the intracellular K(+) to Na(+) ratios showed that transgenic lines were able to retain more K(+) than the control under salt stress. Although plants and yeast cannot be compared in an absolute sense, these results indicate that the mechanism controlling the positive effect of the HAL1 gene on salt tolerance may be similar in transgenic plants and yeast.

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Living related liver transplantation is one of the strategies currently used to increase the donor pool. A preoperative and non-invasive estimate of the donor's liver volume is needed to ensure sufficient functional liver reserve for survival after resection, and to obtain a graft of adequate volume to suit the recipient's features. A method based on a preoperative abdominal computerised axial tomography of the donor, that enables the volume and mass of the whole liver, and the graft, to be calculated is herein described. The compatibility of the estimate with real graft mass after its removal has been proved, and the accuracy of the calculi has been compared with other published methods. Moreover, progressive growth of the recipient liver remnant has been demonstrated in subsequent explorations.

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Black locust (Robinia pseudoacacia L.) immature seeds of different developmental stages were tested for the ability to initiate embryogenic cultures. Best results (average of 12% embryogenic cultures) were obtained when seeds collected 2-3 weeks post-anthesis were cultured for 3 weeks on modified Finer and Nagasawa medium containing 2,4-D (45-90 µM) and BA (2.2 µM) and then transferred to the same medium without growth regulators. Embryo conversion was obtained from naked or encapsulated somatic embryos derived from a long-term embryogenic line. Without cold treatment, 71% of naked embryos and 41% of the encapsulated embryos converted into plants. Fifteen days of cold treatment increased conversion rates up to 95% for naked embryos and 80% for encapsulated embryos. Recovered plantlets were acclimatized and grown in the greenhouse.

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The authors present a new case of intestinal cystic pneumatosis that presented with a picture similar to acute appendicitis. The literature was reviewed without finding any case of this form of presentation and the characteristics of the disease are summarized. The advantages of separately classifying cases of necrosing acute enteritis are indicated.

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Hypocotyl-derived calli obtained in agar solidified medium with several growth regulator combinations gave rise to proembryonal masses and globular embryos when transferred to liquid media with lower growth regulator and higher NH4HO3 levels. By transferring cultures from liquid media to different solidified media, new embryo formation took place, but further development of these embryos or those previously induced depended on the characteristics of these media. Normal development was only achieved on 8 g/l agar solidified medium without growth regulators. Typical cotyledonary embryos developed into whole plants when transferred to this same medium.

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