A novel tool for stable nitrogen isotope analysis in aqueous samples.

RATIONALE: Bulk stable isotope analysis (BSIA) of dissolved matter (e.g. dissolved organic carbon, total nitrogen bound (TNb ), etc.) is of particular importance since this pool is a prime conduit in the cycling of N and C. Studying the two elemental pools is of importance, as transformation and transport processes of N and C are inextricably linked in all biologically mediated systems. No system able to analyze natural abundance stable carbon and nitrogen isotope composition in aqueous samples (without offline sample preparation) and simultaneously has been reported so far. Extension of the high-temperature combustion (HTC) system, to be capable of measuring TNb stable nitrogen isotope composition, is described in this study. METHODS: To extend the TOC analyzer to be capable of measuring TNb , modifications from the HTC high-performance liquid chromatography/isotope ratio mass spectrometry (HPLC/IRMS) interface were implemented and expanded. A reduction reactor for conversion of NOx into N2 was implemented into the new developed system. The extension addresses mainly the development of the focusing unit for nitrogen and a degassing device for online separation of TNb from molecular nitrogen (N2 ) prior to injection. RESULTS: The proof of principle of the system was demonstrated with different compound solutions. In this initial testing, the δ15 NAIR-N2 values of the tested compounds were determined with precision and trueness of typically ≤0.5‰. Good results (u ≤ 0.5‰) could be achieved down to a TNb concentration of 40 mgN/L and acceptable results (u ≤ 1.0‰) down to 5 mgN/L. In addition, the development resulted in the first system reported to be suitable for simultaneous and direct δ13 C and δ15 N BSIA of aqueous samples. CONCLUSIONS: The development resulted in the first system shown to be suitable for both δ13 C and δ15 N direct BSIA in aqueous samples. This system could open up new possibilities in SIA-based research fields. Copyright © 2016 John Wiley & Sons, Ltd.

Affected connectivity organization of the reward system structure in obesity.

With the prevalence of obesity rapidly increasing worldwide, understanding the processes leading to excessive eating behavior becomes increasingly important. Considering the widely recognized crucial role of reward processes in food intake, we examined the white matter wiring and integrity of the anatomical reward network in obesity. Anatomical wiring of the reward network was reconstructed derived from diffusion weighted imaging in 31 obese participants and 32 normal-weight participants. Network wiring was compared in terms of the white matter volume as well as in terms of white matter microstructure, revealing lower number of streamlines and lower fiber integrity within the reward network in obese subjects. Specifically, the orbitofrontal cortex and striatum nuclei including accumbens, caudate and putamen showed lower strength and network clustering in the obesity group as compared to healthy controls. Our results provide evidence for obesity-related disruptions of global and local anatomical connectivity of the reward circuitry in regions that are key in the reinforcing mechanisms of eating-behavior processes.

Detection of non-alcoholic steatohepatitis in patients with morbid obesity before bariatric surgery: preliminary evaluation with acoustic radiation force impulse imaging.

OBJECTIVE: To investigate the utility of acoustic radiation force impulse (ARFI) imaging, with the determination of shear wave velocity (SWV), to differentiate non-alcoholic fatty liver disease (NAFLD) from non-alcoholic steatohepatitis (NASH) in patients with morbid obesity before bariatric surgery. METHODS: Thirty-two patients with morbid obesity were evaluated with ARFI and conventional ultrasound before bariatric surgery. The ARFI and ultrasound results were compared with liver biopsy findings, which is the reference standard. The patients were classed according to their histological findings into three groups: group A, simple steatosis; group B, inflammation; and group C, fibrosis. RESULTS: The median SWV was 1.57 ± 0.79 m/s. Hepatic alterations were observed in the histopathological findings for all the patients in the study (100 %), with the results of the laboratory tests proving normal. Differences in SWV were also observed between groups A, B and C: 1.34 ± 0.90 m/s, 1.55 ± 0.79 m/s and 1.86 ± 0.75 m/s (P < 0.001), respectively. The Az for differentiating NAFLD from NASH or fibrosis was 0.899 (optimal cut-off value 1.3 m/s; sensitivity 85 %; specificity 83.3 %). CONCLUSION: The ARFI technique is a useful diagnostic tool for differentiating NAFLD from NASH in asymptomatic patients with morbid obesity. KEY POINTS : • Acoustic radiation force impulse imaging provides ultrasonic shear wave velocity measurements. • SWV measurements were higher in patients with inflammation or fibrosis than NAFLD. • ARFI differentiates NAFLD from NASH in patients with morbid obesity. • Results suggest that ARFI can detect NASH in asymptomatic morbidly obese patients.

Electrohydrodynamic deposition of nanotitanium doped hydroxyapatite coating for medical and dental applications.

Nano-sized titanium containing hydroxyaptite has been prepared, the particle size of nanoTiHA was shown to be 12-20 nm in width and 30-40 nm in length, smaller than that of nanoHA. X-ray diffraction analysis revealed the phase purity of nanoTiHA produced. Antimicrobical assays demonstrated that nanoTiHA has excellent growth inhibitory properties, and is able to inhibit the growth of all bacterial strains tested, both Gram-negative and Gram-positive species, including multi-antibiotic resistant EMRSA 15 and EMRSA 16 'superbugs'. Biocidal activity against all four Staphylococcus spp was also shown at the concentration tested. Nanostuctured TiHA coating was successfully deposited onto Ti surfaces using EHDA spraying under optimized processing conditions with the thickness of the coating being further controlled by the spraying time. All of the nanoTiHA coated Ti surfaces were able to support human osteoblast (HOB) cell attachment and growth. The coating thickness did not significantly influence the proliferation of HOB cells on nanoTiHA coatings, while the ability of nanoTiHA coating to support HOB cell differentiation was demonstrated from the alkaline phosphatase activity. Our study showed that nanoTiHA has excellent anti-bacterial properties and the thin nanoTiHA coating was also able to support the attachment, growth and differentiation of HOB cells. Therefore, nanoTiHA coating could pave the way for the development of the next generation of dental and orthopedic implants by offering anti-infection potential in addition to osteoconductivity.

Beer consumption reduces cerebral oxidation caused by aluminum toxicity by normalizing gene expression of tumor necrotic factor alpha and several antioxidant enzymes.

Aluminum (Al)-induced neurotoxicity is well known and different salts of aluminum have been reported to accelerate oxidative damage to biomolecules. The present study has examined whether silicon consumed in the form of silicic acid or beer could potentially inhibit aluminum toxicity in the brain. Male mice were administered with Al(NO(3))(3) orally at a dose of 450 mg/kg/day in drinking water for 3 month. Experimental mice were given Al(NO(3))(3) along with 50 mg/L of silicic acid or with 0.5 ml/day of beer. Al brain levels in the Al group were four times higher than those of control mice while silicic acid and beer group values were 40% lower than those of the Al group. We have observed that beer prevented accumulation of lipid damage significantly, which resulted from aluminum intake. Decline in the expression of mRNA of endogenous antioxidant enzymes associated with aluminum administration was also inhibited by beer and silicic acid. The tumor necrosis factor alpha (TNFalpha) RNA expression was normalized in silicic acid and beer groups. Very high and significant correlations were found for the different parameters tested suggesting that moderate consumption of beer, due to its silicon content, effectively protects against the neurotoxic effects of aluminum.

Standardized Hypericum perforatum reduces oxidative stress and increases gene expression of antioxidant enzymes on rotenone-exposed rats.

Since oxidative stress is implicated in the pathophysiology of dementia and depression, this study was designed to investigate the pro-oxidant activity of rotenone, the protective role of standardized extract of Hypericum perforatum (SHP), as well as the mRNA levels of antioxidant enzymes, in brain homogenates of rats following exposure to rotenone and SHP extract. Quercetin in liposomes, one active constituent, was tested in the same experimental conditions to serve as a positive control. The animals received pretreatment with SHP (4 mg/kg) or quercetin liposomes (25 and 100 mg/kg) 60 min before of rotenone injection (2 mg/kg). All treatments were given intraperitoneally in a volume of 0.5 ml/kg body weight, for 45 days. Rotenone treatment increased activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and levels of malondialdehyde (MDA). The content of reduced glutathione (GSH) was decreased due to chronic rotenone treatment. Rotenone significantly induced the gene expression of CuZnSOD, MnSOD; CAT and GPx in brain. In contrast, SHP extract exerted an antioxidant action which was related with a decreased of MnSOD activity and mRNA levels of some antioxidant enzymes evaluated. Liposomal quercetin treatment resulted in a significant preservation of the activities of antioxidant enzymes and a decreased in the mRNA levels of these antioxidant enzymes. One possible mechanism of action of SHP extract may be related to quercetin in protecting neurons from oxidative damage. Therefore standardized extract of H. perforatum could be a better alternative for depressed elderly patients with degenerative disorder exhibiting elevated oxidative stress status.

Connectomics-based structural network alterations in obsessive-compulsive disorder.

Given the strong involvement of affect in obsessive-compulsive disorder (OCD) and recent findings, the current cortico-striato-thalamo-cortical (CSTC) model of pathophysiology has repeatedly been questioned regarding the specific role of regions involved in emotion processing such as limbic areas. Employing a connectomics approach enables us to characterize structural connectivity on a whole-brain level, extending beyond the CSTC circuitry. Whole-brain structural networks of 41 patients and 42 matched healthy controls were analyzed based on 83 × 83 connectivity matrices derived from cortical and subcortical parcellation of structural T1-weighted magnetic resonance scans and deterministic fiber tracking based on diffusion tensor imaging data. To assess group differences in structural connectivity, the framework of network-based statistic (NBS) was applied. Graph theoretical measures were calculated to further assess local and global network characteristics. The NBS analysis revealed a single network consistently displaying decreased structural connectivity in patients comprising orbitofrontal, striatal, insula and temporo-limbic areas. In addition, graph theoretical measures indicated local alterations for amygdala and temporal pole while the overall topology of the network was preserved. To the best of our knowledge, this is the first study combining the NBS with graph theoretical measures in OCD. Along with regions commonly described in the CSTC model of pathophysiology, our results indicate an involvement of mainly temporo-limbic regions typically associated with emotion processing supporting their importance for neurobiological alterations in OCD.

Long-lived charge-separated states in bacterial reaction centers isolated from Rhodobacter sphaeroides.

We studied the accumulation of long-lived charge-separated states in reaction centers isolated from Rhodobacter sphaeroides, using continuous illumination, or trains of single-turnover flashes. We found that under both conditions a long-lived state was produced with a quantum yield of about 1%. This long-lived species resembles the normal P(+)Q(-) state in all respects, but has a lifetime of several minutes. Under continuous illumination the long-lived state can be accumulated, leading to close to full conversion of the reaction centers into this state. The lifetime of this accumulated state varies from a few minutes up to more than 20 min, and depends on the illumination history. Surprisingly, the lifetime and quantum yield do not depend on the presence of the secondary quinone, Q(B). Under oxygen-free conditions the accumulation was reversible, no changes in the normal recombination times were observed due to the intense illumination. The long-lived state is responsible for most of the dark adaptation and hysteresis effects observed in room temperature experiments. A simple method for quinone extraction and reconstitution was developed.

Visceral leishmaniasis: diagnosis by ultrasound-guided fine needle aspiration of an axillary node.

A 77-year-old woman presented with fever up to 39 degrees C and acute pain in the left upper quadrant and renal fossa. Full blood count and biochemical screen revealed a haemoglobin (Hb) of 9.8 g dl(-1), an increased erythrocyte sedimentation rate and an elevated lactate dehydrogenase, all other parameters were normal. Thoracic and abdominal CT demonstrated two enlarged lymph nodes in the left axilla, and splenic infarcts. Ultrasound-guided fine needle aspiration of one of the axillary lymph nodes revealed macrophages filled with leishmanias.

Effect of fraxetin and myricetin on rotenone-induced cytotoxicity in SH-SY5Y cells: comparison with N-acetylcysteine.

The purpose of this study was to investigate the potential neuroprotective effects of myricetin (flavonoid) and fraxetin (coumarin) on rotenone-induced apoptosis in SH-SY5Y cells, and the possible signal pathway involved in a neuronal cell model of Parkinson's disease. These two compounds were compared to N-acetylcysteine. The viability of cells was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and cytotoxicity was assayed by lactate dehydrogenase (LDH) released into the culture medium. Parameters related to apoptosis, such as caspase-3 activity, the cleavage of poly(ADP-ribose) polymerase and the levels of reactive oxygen species were also determined. Rotenone caused a time- and dose-dependent decrease in cell viability and the degree of LDH release was proportionally to the effects on cell viability. Cells were pretreated with fraxetin, myricetin and N-acetylcysteine at different concentrations for 30 min before exposure to rotenone. Cytotoxicity of rotenone (5 microM) for 16 h was significantly diminished as well as the release of LDH into the medium, by the effect of fraxetin, myricetin and N-acetylcysteine, with fraxetin (100 microM) and N-acetylcysteine (100 microM) being more effective than myricetin (50 microM). Rotenone-induced apoptosis in SH-SY5Y cells was detected by an increase in caspase-3 activity and in the cleavage of poly(ADP-ribose) polymerase. After exposing these cells to rotenone, a significant increase in reactive oxygen species preceded apoptotic events. Fraxetin (100 microM) and N-acetylcysteine (100 microM) not only reduced rotenone-induced reactive oxygen species formation, but also attenuated caspase-3 activity and poly(ADP-ribose) polymerase cleavage at 16 h against rotenone-induced apoptosis. The effect of fraxetin in both experiments was similar to that of N-acetylcysteine. These results demonstrated the protective action of fraxetin and suggest that it can reduce apoptosis, possibly by decreasing free radical generation in SH-SY5Y cells. Myricetin at 100 microM was without any preventive effect.

Palpable breast lesions: utility of Doppler sonography for diagnosis of malignancy.

This study was designed to find whether there are any differences between benign and malignant palpable breast lesions as they are seen on grey-scale and colour-Doppler and on power-Doppler sonography; to determine which variables for each technique are most helpful in distinguishing any such differences; and to see whether the use of an echo-enhancing agent gives better results in the differential diagnosis. Forty-five palpable breast lesions (16 benign and 29 malignant) were evaluated in a preoperative study using grey-scale sonography, colour-Doppler sonography and power-Doppler sonography before and after administration of an echo-enhancing agent (Levovist). We reached the following conclusions: (1) In the grey-scale ultrasound study of palpable breast lesions the presence of microcalcifications, acoustic shadowing and non-well-defined margins are related to malignancy. (2) Colour- and power-Doppler sonography may help in the differential diagnosis. (3) The use of an echo enhancer (Levovist) accentuates these differences and enables them to be noted in other variables, such as pulsatility index, nodule-to-vascularity ratio and number of poles.

Case report: Conservative management of an arteriovenous fistula of the inferior epigastric artery.

We present a case of pseudoaneurysm and arteriovenous fistula of the inferior epigastric artery secondary to the placement of a drain during a surgical intervention. We stress the utility of colour Doppler ultrasound and arteriography embolisation in diagnosis and treatment, respectively.

High-resolution ultrasound associated with aspiration biopsy in the follow-up of patients with differentiated thyroid cancer.

OBJECTIVE: To assess the value of ultrasound in the follow-up of patients undergoing surgery for differentiated thyroid carcinoma. SUBJECTS: The study included 89 patients (70 women and 19 men) with differentiated thyroid carcinoma (76 papillary and 13 follicular cancer). METHODS: High-frequency ultrasound (US) was used in the evaluation of 89 subjects who underwent surgery for thyroid carcinoma. Fine-needle aspiration was performed in cases with positive US. In addition, determinations of thyroglobulin (Tgb) in serum, scintigraphy with (131)I, and cervical palpation were evaluated. We determined sensitivity, specificity, and overall accuracy for each of these diagnostic methods. RESULTS: Ultrasonography was positive in 22 subjects, 16 in the nodal area and 6 in the thyroid bed. Twenty-two subjects received fine-needle aspiration with US control; 13 (59%) of 22 were positive for cancer. The results of the US for detecting neoplastic disease showed a sensitivity of 65%, specificity of 86%, and overall accuracy of 82%. The overall accuracy for scintigraphy was 88% and for Tgb, 91%. CONCLUSION: We concluded that US can be included in the follow-up protocol for patients undergoing surgery for differentiated cancer of thyroid, as a valuable tool to localize the recurrence. This technique is particularly useful in the evaluation of patients who are found to have elevated Tgb levels.

Pharmacological modification of endogenous antioxidant enzymes by ursolic acid on tetrachloride-induced liver damage in rats and primary cultures of rat hepatocytes.

The purpose of this study was to investigate possible protective effects of ursolic acid against CCl4-induced alterations of antioxidant defence enzymes in vivo as well as its effects against CCl4-intoxication in vitro. Pre-treatment of rats with ursolic acid significantly reduced serum levels of glutamate-oxalate-transaminase and glutamate-pyruvate-transaminase previously increased by administration of CCl4. Treatment with ursolic acid also significantly reversed the decreased superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase activities and glutathione levels in the liver, as the concentration of reduced glutathione was increased and the content of oxidized glutathione decreased in ursolic acid treated groups. Levels of lipid peroxidation were higher in the CCl4 group but the increase was also reduced after drug treatment (p < 0.01 for 1, 2.5 and 5 mmol/kg). In vitro results indicated that addition to the culture medium of ursolic acid (p < 0.01 for 500 microM) resulted in a reduction of glutamate-oxalate-transaminase, lactate dehydrogenase activities and in a good survival rate for the CCl4-intoxicated hepatocytes. Ursolic acid also ameliorated lipid peroxidation in primary cultured rat hepatocytes exposed to CCl4, as demonstrated by a reduction in malondialdehyde production. Moreover, ursolic acid (50-500 microM) showed radical scavenging properties in terms of hydroxyl formation. The results obtained suggest that ursolic acid treatment can normalize the disturbed antioxidant status of rats intoxicated with CCl4 by maintaining the levels of glutathione and by inhibiting the production of malondialdehyde due to its radical scavenging properties.

[Corynebacterium urealyticum in renal trasplantation. CT and sonography imaging characteristics of encrusted cistitis and pielitis]. / Corynebacterium urealyticum en pacientes con trasplante renal. Imágenes características de la TC y ultrasonografía de la cistitis y pielitis incrustante.

PURPOSE: Its described three cases of Corynebacterium urealyticum (CU) infection in patients with renal transplantation and one of its most serious consequences: encrusted pyelitis and cystitis. It is explained the principal keys for its diagnosis, based in the appearance of alkaline pH in in urine analysis (alkaline urine), positives urinary cultures for CU, and the CT and US studies revealed the characteristic images of calcifications in the wall of renal pelvis and bladder. PATIENTS: Three male patients with renal transplantation and CU infection that caused encrusted pyelitis in two of the cases and encrusted cystitis in one case. RESULTS: Calcifications of the urinary tract were noticed in CT in all the patients. In two cases bladder stones were linear, and in the third case they were fundamentally coarse and placed in pelvis. The diagnosis suspicion showed by the images was confirmed by the use of prolonged urine cultures, necessary for detecting CU. All the patients were treated with vancomycin, with success in two of the cases and, finally needing surgery, and after loss of the graft, in the other case. CONCLUSION: Encrusted pyelitis and cystitis are cronic and severe infections of the urinary tract. Calcic struvite incrustations in the urothelium are characteristics of this infection. CT is a choice technique for the diagnosis and followup of the calcifications after treatment.

[Burkitt's lymphoma: atypical localization]. / Linfoma de Burkitt: Localización atípica.

We present a case of Burkitt's lymphoma, American type, with massive abdominal involvement, in a 11 years old boy, who presented with mucous-cutaneous paleness, cephalalgia and melaena. The localization of the lesion in the gallbladder and the rectum is stressed as being exceptional. We emphasize the importance of a rapid diagnosis to start early chemotherapy because this lesion grows rapidly. In our case after eight days of chemotherapy treatment there was a 75% reduction of the tumor mass.

[Haemophagocytic syndrome and cutaneous T-cell lymphoma]. / Síndrome hemofagocítico y linfoma cutáneo de células T.

Haemophagocytic syndrome is a rare disorder of immune regulation. Clinical features are fever, haemophagocytosis, hepatosplenomegaly, pancytopenia, lymph nodes enlargement, hypertriglyceridaemia and coagulopathy. Systemic findings may also include pulmonary infiltrates, renal failure and an inappropriate antidiuretic state. It has been described associated to many diseases, like lymphomas, most of them T-cell lymphomas, infections and systemic diseases, among other entities. Haemopoietic cells are actively ingested by monocytes and macrophages in lymph nodes, bone marrow, liver and spleen. This is a diagnostic criteria for haemophagocytic syndrome. The treatment of haemophagocytic syndrome is difficult and requires intensive supportive therapy, treatment of coagulopathy disorders, high-dose corticosteroids and immunosuppressive treatment, although in most cases there is no response to treatment and the evolution is fatal. The T-cell lymphomas that involve subcutaneous tissue and simulate panniculitis are classified recently as primary cutaneous T-cell lymphomas, and their presentation as inflammatory nodules of the legs are uncommon.

Neuroprotective Properties of Standardized Extracts of Hypericum perforatum on Rotenone Model of Parkinson's Disease.

Hipericum perforatum is a well-known herbal for its antidepressant property. Recently, it has been shown to have nootropic effects against neurodegenerative disorders. The aim of the present study was to evaluate the protective role of chronic administration of two standardized extract of Hypericum perforatum SHP1 rich in hyperforin (6%) and SHP2 extract poor in hyperforin (0.2%) on the neurodegeneration induced by chronic administration of rotenone in rats. Quercetin in liposomes, one active constituent, was tested in the same experimental conditions. The animals received pretreatments with SHP1 (4 mg/Kg, ip), SHP2 (4 mg/Kg, ip) or quercetin liposomes (25 and 100 mg/kg, ip) 60 min before of rotenone injection (2.5 mg/kg) for 45 days. Pretreatment of the animals with SHP1 and SHP2 efficiently halted deleterious toxic effects of rotenone, revealing normalization of catalepsy in addition to amelioration of neurochemical parameters. Also, SHP1 reduced neuronal damage, diminishing substantia nigra dopaminergic cell death caused by the pesticide, indicating benefit of neuroprotective therapy. In general, the SHP1 was more active than SHP2. In addition, SHP1 inhibited the apoptotic cascade by decreasing Bax levels. The results presented here indicate that mainly hyperforin and quercetin, may be involved in the neuroprotective action of Hypericum standardized extracts. Combination of dietary antioxidants could provide better therapeutic advantage for the management of Parkinson, and possibly other neurodegenerative disorders. Therefore H. perforatum standardized extract enriched in hyperforin, could be a better alternative for depressed elderly patients with degenerative disorders exhibiting elevated oxidative stress status.

Effects of seaweed-restructured pork diets enriched or not with cholesterol on rat cholesterolaemia and liver damage.

Seaweed enriched-restructured pork (RP) is a potential functional food. However, indications of adverse effects associated with herbal medications, which include among others liver failure, toxic hepatitis, and death have been reported. Cholesterol feeding produces hepatomegalia and fat liver infiltration. The effect of seaweed-RP diet, cholesterol-enriched or not, on plasma cholesterol, liver damage markers, structure, and cytochrome CYP4A-1 were evaluated after 5 wk. Eight rat groups were fed a mix of 85% AIN-93M rodent-diet plus 15% RP. The Cholesterol-control (CC), Cholesterol-Wakame (CW), Cholesterol-Nori (CN) and Cholesterol-Sea Spaghetti (CS) groups respectively consumed similar diets to control (C), Wakame (W), Nori (N), and Sea Spaghetti (S) but as part of hypercholesterolaemic diets. CN and CS significantly blocked the hypercholesterolaemic effect observed in CC group. After 5-wk, N and S diets increased the CYP4A-1 expression. However, seaweed-RPs were unable to reduce the histological liver alterations observed in CC group. Larger and more abundant hepatocellular alterations were found in CS and CN rats suggesting that the hypocholesterolaemic effects of these seaweed-RPs seem to be a two-edged sword as they increased liver damage. Future studies are needed to understand the involved mechanisms.