Endogenous NO Is Involved in Dissimilar Responses to Rehydration and Pb(NO3)2 in Ramalina farinacea Thalli and Its Isolated Phycobionts.

Lichens undergo desiccation/rehydration cycles and are permeable to heavy metals, which induce free radicals. Nitrogen monoxide (NO) regulates important cellular functions, but the research on lichen NO is still very scarce. In Ramalina farinacea thalli, NO seems to be involved in the peroxidative damage caused by air pollution, antioxidant defence and regulation of lipid peroxidation and photosynthesis. Our hypothesis is that NO also has a critical role during the rehydration and in the responses to lead of its isolated phycobionts (Trebouxia sp. TR9 and Trebouxia jamesii). Therefore, we studied the intracellular reactive oxygen species (ROS) production, lipid peroxidation and chlorophyll autofluorescence during rehydration of thalli and isolated microalgae in the presence of a NO scavenger and Pb(NO3)2. During rehydration, NO scavenging modulates free radical release and chlorophyll autofluorescence but not lipid peroxidation in both thalli and phycobionts. Pb(NO3)2 reduced free radical release (hormetic effect) both in the whole thallus and in microalgae. However, only in TR9, the ROS production, chlorophyll autofluorescence and lipid peroxidation were dependent on NO. In conclusion, Pb hormetic effect seems to depend on NO solely in TR9, while is doubtful for T. jamesii and the whole thalli.

Lichen rehydration in heavy metal-polluted environments: Pb modulates the oxidative response of both Ramalina farinacea thalli and its isolated microalgae.

Lichens are adapted to desiccation/rehydration and accumulate heavy metals, which induce ROS especially from the photobiont photosynthetic pigments. Although their mechanisms of abiotic stress tolerance are still to be unravelled, they seem related to symbionts' reciprocal upregulation of antioxidant systems. With the aim to study the effect of Pb on oxidative status during rehydration, the kinetics of intracellular ROS, lipid peroxidation and chlorophyll autofluorescence of whole Ramalina farinacea thalli and its isolated microalgae (Trebouxia TR1 and T. TR9) was recorded. A genetic characterization of the microalgae present in the thalli used was also carried out in order to assess possible correlations among the relative abundance of each phycobiont, their individual physiological responses and that of the entire thallus. Unexpectedly, Pb decreased ROS and lipid peroxidation in thalli and its phycobionts, associated with a lower chlorophyll autofluorescence. Each phycobiont showed a particular pattern, but the oxidative response of the thallus paralleled the TR1's, agreeing with the genetic identification of this strain as the predominant phycobiont. We conclude that: (1) the lichen oxidative behaviour seems to be modulated by the predominant phycobiont and (2) Pb evokes in R. farinacea and its phycobionts strong mechanisms to neutralize its own oxidant effects along with those of rehydration.

Phylogenetics and phylogeography of Euphorbia canariensis reveal an extreme Canarian-Asian disjunction but limited inter-island colonization.

Euphorbia canariensis is an iconic endemic species representative of the lowland xerophytic communities of the Canary Islands. It is widely distributed in the archipelago despite having diasporas unspecialized for long-distance dispersal. Here, we reconstructed the evolutionary history of E. canariensis at two levels: a time-calibrated phylogenetic analysis aimed at clarifying interspecific relationships and large-scale biogeographic patterns; and a phylogeographic study focused on the history of colonization across the Canary Islands. For the phylogenetic study, we sequenced the ITS region for E. canariensis and related species of Euphorbia sect. Euphorbia. For the phylogeographic study, we sequenced two cpDNA regions for 28 populations representing the distribution range of E. canariensis. The number of inter-island colonization events was explored using PAICE, a recently developed method that includes a sample size correction. Additionally, we used species distribution modelling (SDM) to evaluate environmental suitability for E. canariensis through time. Phylogenetic results supported a close relationship between E. canariensis and certain Southeast Asian species (E. epiphylloides, E. lacei, E. sessiliflora). In the Canaries, E. canariensis displayed a west-to-east colonization pattern, not conforming to the "progression rule", i.e. the concordance between phylogeographic patterns and island emergence times. We estimated between 20 and 50 inter-island colonization events, all of them in the Quaternary, and SDM suggested a late Quaternary increase in environmental suitability for E. canariensis. The extreme biogeographic disjunction between Macaronesia and Southeast Asia (ca. 11,000 km) parallels that found in a few other genera (Pinus, Dracaena). We hypothesize that these disjunctions are better explained by extinction across north Africa and southwest Asia rather than long-distance dispersal. The relatively low number of inter-island colonization events across the Canaries is congruent with the low dispersal capabilities of E. canariensis.

Visual and semi-quantitative analysis of 6-[18F]FDOPA PET/CT in patients with brain tumors and suspected tumor recurrence versus radionecrosis.

INTRODUCTION: Amino acid PET is a tool recommended by the main neuroimaging societies in the differential diagnosis between radionecrosis (RNC) and umour recurrence (TR) in brain tumours, but its use in our country is still limited. The aim of this work is to present our experience with 6-[18F]FDOPA PET/CT (FDOPA) in brain tumours (primary and M1), comparing these results with other published results. MATERIAL AND METHODS: Retrospective study of 62 patients with suspected tumour recurrence (TR): 42 brain metastases (M1) and 20 primary, who underwent FDOPA. Images were analysed visually and semi-quantitatively, obtaining SUVmax and SUVmaxlesion/SUVmaxstriatum (L/S) and SUVmaxlesion/SUVmaxcortex (L/C) ratios. The diagnostic validity of PET was analysed and the best performing cut-off points were calculated. PET results were compared with clinical-radiological follow-up and/or histopathology. RESULTS: TR was identified in 49% of M1 and 76% of brain primaries. The best performing FDOPA interpretation was visual and semi-quantitative, with a sensitivity and specificity in primaries of 94% and 80% and in M1s of 96% and 72% respectively. The cut-off points with the best diagnostic performance were L/C1.44 in M1 and L/C1.55 in primaries. There are discrepant results with other published results. CONCLUSION: FDOPA PET/CT is a useful tool in the differential diagnosis between recurrence and RNC in brain tumours. It is needed a standardization to contribute to homogenise FDOPA results a inter-centre level.

Advances in the management of trigeminal neuralgia.

Trigeminal neuralgia (TN), one of the most intense forms of facial pain, has been the subject of great clinical interest. Significant advances have been made in its management, including surgical treatment and imaging of the trigeminal nerve and associated neurovascular compression. The different options for surgical treatment, recent advances in each as well as novel methods of imaging of the trigeminal nerve focusing on diffusion tensor imaging/tractography will be discussed.

Medical management of Ménière's disease: a 10-year case series and review of literature.

Ménière's disease is frequent in our area. It is a disabling pathology that affects the patient's quality of life. Its etiology and pathophysiology remain unclear and there are some therapeutic alternatives with controversial results. We present our series and treatment protocol for Ménière's disease and discuss the current evidence regarding its medical treatment. In the last 10 years, 252 patients were diagnosed with Ménière's disease based on their symptoms, and the results of tonal audiometry, videonystagmography and caloric stimulation tests. All cases received medical treatment according to our management protocol. Ménière's disease is more frequent in women (54.76%); 83.73% of cases are unilateral. Among these, vertigo was observed in 93.7%, hearing loss in 88.1%, tinnitus in 86.1% and pathologic caloric stimulation tests in 71% (88.27% with a reduced vestibular response). A 5-year follow-up was performed in 89.6% of the patients. Subjective improvement as reported by patients was achieved in 94.4% of the cases. There is great controversy about the medical treatment of Ménière's disease. We found no evidence for the most adequate medical treatment among the different alternatives described in literature. The patient's acceptance and understanding of the disease is very important.

Preradiotherapy MR Imaging: A Prospective Pilot Study of the Usefulness of Performing an MR Examination Shortly before Radiation Therapy in Patients with Glioblastoma.

BACKGROUND AND PURPOSE: Current protocols in patients with glioblastoma include performing an MR examination shortly after surgery and then 2-6 weeks after ending concomitant chemoradiotherapy. The assessment of this first postradiotherapy examination is challenging because the pseudoprogression phenomenon may appear. The aim of this study was to explore if performing an MR examination shortly before radiation therapy (preradiotherapy MR imaging) could improve the radiologic assessment of patients with glioblastoma. MATERIALS AND METHODS: A preradiotherapy MR imaging examination was prospectively performed before the start of radiation therapy in 28 consecutive patients with glioblastoma who had undergone surgical resection. Tumor response to chemoradiotherapy was assessed twice: with the early postoperative MR examination as baseline and with the preradiotherapy MR imaging examination as baseline. In addition, tumor growth in the preradiotherapy MR imaging examination was evaluated, and its correlation with patient survival was assessed with Kaplan-Meier analysis and Cox regression. RESULTS: Tumor progression after radiation therapy was found in 16 patients, corresponding to pseudoprogression in 7 of them (44%). Four assessments of pseudoprogression switched to partial response or stable disease when preradiotherapy MR imaging was the baseline examination, and the ratio of pseudoprogression was reduced to 25% (3 of 12). Significant differences in survival were found when patients were stratified according to the pattern of tumor growth on preradiotherapy MR imaging (median overall survival "no-growth," 837 days; "focal-growth," 582 days; "global-growth," 344 days; P = .001). CONCLUSIONS: Performing a preradiotherapy MR imaging examination may improve the clinical management of patients with glioblastoma by reducing the ratio of pseudoprogression assessments and providing prognostic information.

Serie de casos clínicos de pacientes con Miopatía inflamatoria idiopática y Enfermedad pulmonar intersticial del registro de Miopatías inflamatorias idiopáticas de la Sociedad Argentina de Reumatología / Clinical case series of patients with idiopathic inflammatory myopathy and interstitial lung disease from the SAR's Registry of Idiopathic Inflammatory Myopathies

Las Miopatías Inflamatorias Idiopáticas (MII) son un grupo heterogéneo de enfermedades que se caracterizan por debilidad muscular e inflamación subyacente en la biopsia muscular. Los principales órganos afectados son el músculo, la piel y también puede afectarse el pulmón. Se distinguen dentro de los subtipos clínicos como Polimiositis (PM), Dermatomiositis (DM), DM con la variante Dermatomiositis Clínicamente Amiopática (DMCA), el Síndrome Antisintetasa (SAS), la Miositis Necrotizante Inmunomediada, la Miositis por Cuerpos de Inclusión (MCI) y la Miositis Asociada a Neoplasia. La presencia de ciertos anticuerpos específicos y asociados predispone al desarrollo de manifestaciones clínicas, determinando el pronóstico de la enfermedad. Se presentan 4 pacientes del Registro de MII de la Sociedad Argentina de Reumatología (SAR) con estas características: un paciente con PM y anti Jo-1 positivo y tres pacientes con DM (uno con DMCA y anti-RO 52 y dos pacientes con anti-PL7 y anti-TIF1γ respectivamente).

Idiopathic Inflammatory Myopathies (MII) are a heterogeneous group of diseases characterized by muscle weakness and inflammation underlying muscle biopsy. The main organs affected are muscle, skin and the lung can also be affected. They are distinguished within clinical subtypes such as Polymyositis (PM), Dermatomyositis (DM), DM with the variant Clinically Amiopathic Dermatomyositis (DMCA), the Syndrome Antisynthetase (SAS), Immune-mediated Necrotizing Myositis, Body Myositis Inclusion (MCI) and Neoplasia-Associated Myositis. The presence of certain specific and associated antibodies predisposes to the development of clinical manifestations, determining the disease prognosis. 4 patients from the Registry of MII of the Argentine Society of Rheumatology (SAR) are presented with these characteristics: one patient with PM and anti Jo-1 positive and three patients with DM (one with DMCA and anti-RO 52 and two patients with anti-PL7 and anti-TIF1γ respectively).

Serie de casos clínicos de pacientes con Miopatía inflamatoria idiopática y Enfermedad pulmonar intersticial del registro de Miopatías inflamatorias idiopáticas de la Sociedad Argentina de Reumatología / Series of clinical cases of patients with idiopathic inflammatory myopathy and interstitial lung disease from the registry of idiopathic inflammatory myopathies of the Argentine Society of Rheumatology

Las Miopatías Inflamatorias Idiopáticas (MII) son un grupo heterogéneo de enfermedades que se caracterizan por debilidad muscular e inflamación subyacente en la biopsia muscular. Los principales órganos afectados son el músculo, la piel y también puede afectarse el pulmón. Se distinguen dentro de los subtipos clínicos como Polimiositis (PM), Dermatomiositis (DM), DM con la variante Dermatomiositis Clínicamente Amiopática (DMCA), el Síndrome Antisintetasa (SAS), la Miositis Necrotizante Inmunomediada, la Miositis por Cuerpos de Inclusión (MCI) y la Miositis Asociada a Neoplasia. La presencia de ciertos anticuerpos específicos y asociados predispone al desarrollo de manifestaciones clínicas, determinando el pronóstico de la enfermedad. Se presentan 4 pacientes del Registro de MII de la Sociedad Argentina de Reumatología (SAR) con estas características: un paciente con PM y anti Jo-1 positivo y tres pacientes con DM (uno con DMCA y anti- RO 52 y dos pacientes con anti-PL7 y anti-TIF1γ respectivamente).

Idiopathic Inflammatory Myopathies (MII) are a heterogeneous group of diseases characterized by muscle weakness and inflammation underlying muscle biopsy. The main organs affected are muscle, skin and the lung can also be affected. They are distinguished within clinical subtypes such as Polymyositis (PM), Dermatomyositis (DM), DM with the variant Clinically Amiopathic Dermatomyositis (DMCA), the Syndrome Antisynthetase (SAS), Immune-mediated Necrotizing Myositis, Body Myositis Inclusion (MCI) and Neoplasia-Associated Myositis. The presence of certain specific and associated antibodies predisposes to the development of clinical manifestations, determining the disease prognosis. 4 patients from the Registry of MII of the Argentine Society of Rheumatology (SAR) are presented with these characteristics: one patient with PM and anti Jo-1 positive and three patients with DM (one with DMCA and anti-RO 52 and two patients with anti-PL7 and anti-TIF1γ respectively).

Bile duct varices.

The diagnosis of biliary duct varices and portal vein occlusion should be considered when nodular or notched defects in the wall of the biliary duct system are shown by cholangiography or when pedunculated vascular structures in the bile ducts are seen at surgery. We present two cases of common hepatic and common bile duct varices due to portal vein occlusion.

Aggregation behavior of sodium fusidate in aqueous solution.

We analyzed the freezing point depression and pNa measurements for aqueous solutions of sodium fusidate. At concentrations lower than 0.011 mol kg(-1), sodium fusidate behaves as a strong 1:1 electrolyte. At higher concentrations, sodium fusidate self-aggregates. To analyze the results two hypotheses on the monomer concentration are presented and discussed. The first one accepts that the monomer concentration, C(A), is constant and equal to 0.023 mol kg(-1). This concentration corresponds to a break point in the plot of the freezing point depression vs total sodium fusidate concentration, C(A)t. The second hypothesis accepts that C(A) increases with C(A)t following a leveling-off curve. Measurements of hydrodynamic radii and comparison with similar systems, such as sodium taurocholate, strongly support the second hypothesis. The results indicate that at concentrations lower than 0.08 mol kg(-1) the aggregation number increases from 2 to 3. Above this concentration, both the aggregation number and the fraction of bound counterions remain constant, with average values of 3.13 +/- 0.10 and 0.31 +/- 0.05, respectively. Such results indicate that for trimers only one Na+ counterion is involved per aggregate. We propose that this counterion shields the repulsion between the two nearest carboxylate groups which, according to a disklike model in which the monomers are packed with that group alternatively oriented up and down, should hold together. Values for the formation equilibrium constant of aggregates are also calculated. Its dependence with the aggregation number allows the determination of the reversible transfer of a free surfactant ion together with the associated counterions from the bulk solution to the aggregate, the resulting value being w(0) = -4.2k(B)T.

Aggregation behavior of bile salts in aqueous solution.

Freezing point depression, delta T/k, and pNa are measured and analyzed for aqueous solutions of trihydroxy (NaTC) and dihydroxy (NaDC and NaTDC) bile salts. The results show the existence of break points in the plot of delta T/k vs molality at 0.018, 0.013, and 0.007 m, respectively, in good agreement with previous published critical micelle concentration values. Above the break point bile salts form aggregates with average aggregation numbers of 2.59 +/- 0.12 (NaTC), 5.82 +/- 0.04 (NaDC), and 5.42 +/- 0.47 (NaTDC). Fractions of bound counterions are also deduced, being close to 0.3 for the three bile salts studied. This indicates that only one counterion is bound for every three monomers in the aggregate. The different structural models published for the bile salt aggregates are discussed.

A "giant" punch for reduction mammoplasty.

A new instrument, a kind of "giant" punch, is useful in Strömbeck's reduction mammoplasty. Its application makes the upper cylinder of tissue excision an easy maneuver. It also guarantees that even, symmetrical amounts of parenchyma will be removed from both sides. Its three sizes permit three different amounts of tissue removal for varying degrees of reduction or asymmetries.

Risk stratification and outcomes of transluminal endografting for abdominal aortic aneurysm: 7-year experience and long-term follow-up.

PURPOSE: To determine early and late outcomes of transluminal endografting (TE) in patients with abdominal aortic aneurysm (AAA), stratified by predicted risk of procedure-related mortality with conventional operation. MATERIALS AND METHODS: A retrospective study was conducted in consecutive risk-stratified AAA patients undergoing TE at a not-for-profit cardiovascular referral center from March 1994 through November 2000 with follow-up through February 2001. With use of conventional risk strata (0 = low, 1 = minimal, 2 = moderate, and 3 = high), predicted procedure-related mortalities were 0%-1% in stratum 0 (n = 40), 1%-3% in stratum 1 (n = 118), 3%-8% in stratum 2 (n = 116), and 8%-30% in stratum 3 (n = 31). Main outcome measures were: (i) TE procedural success, (ii) procedure-related mortality, (iii) major nonfatal complications, (iv) composite adverse outcome (ii + iii), (v) length of stay (LOS), (vi) freedom from AAA rupture, (vii) late survival, (viii) late complications, and (ix) endoleaks and their classification and management. RESULTS: Women were significantly less likely than men to qualify for and undergo endografting: 24 of 91 (26.4%) women underwent TE, compared to 281 of 684 (41.1%) men. Of 305 attempted TE procedures, 291 (95.4%) were successful, four (1.3%) were urgently converted to open repair, and 10 (3.3%) were aborted. Procedure-related mortalities occurred in eight cases (2.6%) overall and one of 40 (2.5%), one of 118 (0.8%), four of 116 (3.4%), and two of 31 (6.5%) cases for risk strata 0-3, respectively. Perioperative survivors were significantly younger than nonsurvivors (74.3 y +/- 9 vs 81.6 y +/- 5.1; P =.0087). Forty-six patients (15.1%) had major complications. Composite adverse outcome was worse for patients in stratum 3 than those in stratum 1 (P =.0296) and those in strata 0, 1, and 2 combined (P =.026). Procedure-related mortality declined with institutional experience, from 4% among the first 100 patients undergoing TE to 1% among the last 105. For strata 0-3, median LOS were 2, 3, 3, and 4 days, respectively. Seventy patients (22.9%) had 75 endoleaks, of which 30 necessitated additional procedures, 17 self-resolved, and 22 were untreated as of March 1, 2001. Five patients with endoleak died of unrelated causes. One late-onset type IA endoleak (26 mo) resulted in the only AAA rupture and death in the follow-up period among the 291 patients who underwent successful transluminal endograft implantation. Actuarial survival rates at 1 year after TE were 90.3% +/- 1.9% for the overall study group and 97.5% +/- 2.5%, 94% +/- 2.5%, 86.9% +/- 3.3%, and 81.3% +/- 7.7% for risk strata 0-3, respectively. At 5 years, overall actuarial survival was 69.6% +/- 6.1%. Thirty-eight late deaths were attributable to post-TE AAA rupture (n = 1), AAA rupture late after failed TE with no further treatment (n = 1), other cardiovascular disorders (n = 7), cancer (n = 15), other causes (n = 10), and unknown causes (n = 4). Late deaths occurred in risk strata 0-3 at the following rates: two of 40 (5%), 10 of 118 (8.5%), 16 of 116 (13.8%), and 10 of 31 (32.3%), respectively (stratum 0 vs stratum 3, P =.0017; stratum 1 vs stratum 3, P =.003). CONCLUSIONS: TE is safe and confers durable protection against AAA rupture in treated populations. Still, protection is not absolute in patients with endoleaks, because late AAA enlargement and even rupture can occur. Given current knowledge, technology, and practice, careful patient selection and close surveillance of patients after implantation of transluminal endografts is essential.