Bioactive ingredients of huitlacoche (Ustilago maydis), a potential food raw material.

Huitlacoche (Ustilago maydis) is a staple food traditionally consumed in Mexico. On one hand, it is considered a pathogen and a devastating disease for maize (Zea mays), and, conversely, some reports highlight it as a culinary delight and a food alternative for its nutritional and functional characteristics. The present work aimed to compare two different methods: maceration and ultrasound-assisted extraction (UAE), in order to achieve the highest amount of total phenolic compounds (TPC), followed by the antioxidant capacity (AC) measurement, as well as the effect of the in vitro digestion. UAE produced the highest TPC content (13.44 mg GAE/mg ds) for a 1:5 huitlacoche:solvent ratio using ethanol at 75%. The maximum values for AC were 22.5 mg TE/mL (for DPPH assay) and 45.26 mg TE/mL (for ABTS assay). The in vitro digestion showed that AC is maintained and increased through the digestion process. Thus, huitlacoche can be revalorised as a potential food raw material for human nutrition and health.

MRI prostate contouring is not impaired by the use of a radiotherapy image acquisition set-up. An intra- and inter-observer paired comparative analysis with diagnostic set-up images.

PURPOSE: The use of MRI for radiotherapy planning purposes is growing but image acquisition using radiotherapy set-ups has impaired image quality. Whether differences in image acquisition set-up could modify organ contouring has not been evaluated. Therefore, we aimed to evaluate differences in contouring between paired of image sets that were acquired in the same scanning session using different parameters. MATERIAL AND METHODS: Ten patients underwent RT treatment planning with MRI co-registration. MRI was carried out using two different set-ups during the same session, MRI radiotherapy set-ups and MRI diagnostic set-ups. Prostates and rectums were retrospectively contoured in both image sets by 5 radiation oncologists and 4 radiologists. Intra-observer analysis was carried out comparing organ volumes, the Dice coefficient and hausdorff distance values between two contouring rounds. Inter-observer analysis was carried out by comparing individual contours to a generated STAPLE consensus contour, which is considered the gold standard reference. RESULTS: No significant differences were observed between MRI acquisition set-ups. Significant differences were observed for the dice and hausdorff parameters, comparing individual contours to the STAPLE consensus contour, when analysing diagnostic images between rounds, although raw values were similar. CONCLUSION: Prostate and rectum contours did not differ significantly when using diagnostic or radiotherapy MRI acquisition set-ups.

[Paradoxical arterial gas embolism following a direct incisive injury to the skull]. / Embolismo arterial gaseoso paradojico tras una herida incisa craneal directa.

INTRODUCTION: An arterial gas embolism is defined as the presence of air in the arterial circulation. This is an extremely rare cause of stroke that has been described in a multitude of clinical scenarios, generally related to iatrogenic processes. A clinical case is reported in which the arterial gas embolism occurred after a traumatic brain injury, and the most relevant aspects of diagnosis and aetiopathogenesis are reviewed. CASE REPORT: We report the case of a 52-year-old woman with an open craniofacial wound resulting from an attack with an axe. The initial CT scan found fractures in the left zygomatic, sphenoidal and maxillary arches, as well as pneumocephalus in the cavernous sinuses and the right carotid canal. One hour later, the patient showed a neurological deficit in the right hemisphere, and so a new cranial computed tomography scan with multimodal vascular study was urgently requested, which revealed the mobilisation of the pneumocephalus and ruled out a large vessel arterial occlusion. A shunt study using transcranial Doppler and echocardiography showed the presence of a patent foramen ovale to be the cause of arteriovenous communication that justified an arterial gas embolism. The follow-up CT scan at 48 hours confirmed the appearance of a right parietal ischaemic lesion. CONCLUSION: This case reflects the simultaneous presence of air in the arterial and venous circulation of the brain, as well as the peripheral communication through a patent foramen ovale. This production mechanism is poorly documented in the literature.

TITLE: Embolismo arterial gaseoso paradojico tras una herida incisa craneal directa.Introduccion. El embolismo arterial gaseoso se define como la presencia de aire en la circulacion arterial. Se trata de una causa extremadamente rara de ictus que se ha descrito en multitud de escenarios clinicos, generalmente relacionados con procesos yatrogenos. Se aporta un caso clinico en el que el embolismo arterial gaseoso sucedio tras un traumatismo craneoencefalico, y se revisan los aspectos mas relevantes del diagnostico y la etiopatogenia. Caso clinico. Mujer de 52 años que presentaba herida incisa craneofacial tras una agresion con un hacha. La tomografia computarizada inicial objetivo fractura en los arcos cigomatico, esfenoidal y maxilar izquierdos, asi como neumoencefalo en los senos cavernosos y el canal carotideo derecho. Una hora mas tarde, la paciente mostro un deficit neurologico hemisferico derecho, por lo que se solicito de forma urgente una nueva tomografia computarizada craneal con estudio vascular multimodal, que objetivo la movilizacion del neumoencefalo y descarto una oclusion arterial de gran vaso. Un estudio de shunt mediante Doppler transcraneal y ecocardiografia comprobo la presencia de un foramen oval permeable como causa de comunicacion arteriovenosa que justificaba un embolismo arterial gaseoso. La tomografia computarizada de control a las 48 horas confirmo la aparicion de una lesion isquemica parietal derecha. Conclusion. En este caso queda reflejada la presencia simultanea de aire en la circulacion cerebral arterial y venosa y la comunicacion periferica a traves de un foramen oval permeable. Este mecanismo de produccion esta escasamente documentado en la bibliografia.

Síndrome de Horner secundario a vía venosa central / Horner syndrome secondary to a central venous line

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Determination of anticarcinogenic and rescue therapy drugs in urine by photoinduced spectrofluorimetry using multivariate calibration: comparison of several second-order methods.

This paper shows the potential of excitation-emission fluorescence spectroscopy and several second-order methods, such as parallel factor analysis (PARAFAC), multiway partial least-squares (N-PLS) or bilinear least-squares (BLLS), as a multicalibration technique for the analysis of leucovorin (LV) and irinotecan (CPT-11). Although CPT-11 presents native fluorescence, leucovorin has little native fluorescence; however, under irradiation with short-wavelength UV light in the presence of traces of hydrogen peroxide, leucovorin was converted into a highly fluorescent compound. This reaction has been used for the sensitive and selective determination of both compounds. The convenience of analysing the total luminescence spectrum information when using multivariate calibration methods on fluorescence data is demonstrated. Direct determination of mixtures of both drugs in urine was accomplished on the basis of excitation-emission matrices (EEMs) and the three-way multivariate methods.

An environmental friendly method for the automatic determination of hypochlorite in commercial products using multisyringe flow injection analysis.

A multisyringe flow injection analysis system was used for the determination of hypochlorite in cleaning agents, by measurement of the native absorbance of hypochlorite at 292 nm. The methodology was based on the selective decomposition of hypochlorite by a cobalt oxide catalyst giving chloride and oxygen. The difference of the absorbance of the sample before and after its pass through a cobalt oxide column was selected as analytical signal. As no further reagent was required this work can be considered as a contribution to environmental friendly analytical chemistry. The entire analytical procedure, including in-line sample dilution in three steps was automated by first, dilution in a stirred miniature vessel, second by dispersion and third by in-line addition of water using multisyringe flow injection technique. The dynamic concentration range was 0.04-0.78 gL(-1) (relative standard deviation lower than 3%), where the extension of the hypochlorite decomposition was of 90+/-4%. The proposed method was successfully applied to the analysis of commercial cleaning products. The accuracy of the method was established by iodometric titration.

Optical fiber reflectance sensor coupled to a multisyringe flow injection system for preconcentration and determination of 1-naphthylamine in water samples.

A novel optical fiber reflectance sensor is coupled to a multisyringe flow injection system (MSFIA) for the preconcentration and determination of 1-naphthylamine (NPA) in water samples using C18 disks (octadecyl groups). NPA, being a first-class carcinogen, is important from a toxicological point of view and, therefore, its quantification is of considerable interest. In this study, the Griess reaction is used for sensitive and selective spectrophotometric determination of NPA. The reaction involves conversion of nitrite into nitrous acid in acidic medium followed by diazotization of sulphanilic acid and formation of a diazonium salt. The diazonium salt is then combined with NPA to form 4-(sulphophenylazo)-1-naphthylamine, an azo dye. This compound is subsequently retained onto a C18 disk followed by spectrophotometric detection at 540 nm, and it is then eluted with methanol in water (80%, v/v), so that the C18 disk is regenerated for subsequent experiments. Under the established optimum conditions, a calibration graph for NPA was constructed. Good linearity was observed within a concentration range from 10 to 160 microg l(-1). The lineal regression equation is A=(0.0027+/-0.0001) [NPA]+(0.0296+/-0.0047), r=0.9991; relative standard deviation values obtained from the analysis of 10 samples of 10, 80 and 160 microg l(-1) are 4.7, 1.2 and 0.6%, respectively. The mean value relative errors for concentrations of 10, 80, 160 microg l(-1) are 3.4, 0.9 and 0.4%, respectively. The detection and quantification limits were 1.1 and 3.7 microg l(-1). A sampling throughput of 14 injections per hour is achieved. The repeatability calculated for five different C18 disks was E(rel)=2.8%. The proposed technique has been validated by replicate analysis (n=6) of several water samples with spiked NPA, giving satisfactory results.

Small-diameter mesocaval shunts: a 10-year evaluation.

The use of small-diameter portosystemic shunts for the treatment of bleeding esophageal varices caused by portal hypertension has emerged as an outgrowth of the development of polytetrafluoroethylene vascular grafts, which allow the use of a narrow lumen. We report our experience with this type of graft over a 10-year period. Thirty-three patients with good liver function (Child-Pugh class A) were electively operated. The average age of these patients was 45 years (range 17 to 71 years). Twenty-nine patients had liver cirrhosis, one had portal fibrosis, and three had idiopathic portal hypertension. Operative mortality was 3%, and the rebleeding rate was 15%. Postoperative encephalopathy was observed in 14 patients (11%), three of whom had grade III to IV encephalopathy. The remaining 11 patients, had mild encephalopathy that was easily controlled. Postoperative angiography showed shunt patency in 81% of the patients, reduction in portal vein diameter in 33% of the patients, and portal vein thrombosis in 6%. Good postoperative quality of life was observed in 63% of the patients. Survival according to the Kaplan-Meier actuarial method was 81% at 12 months, 56% at 60 months, and 36% at 10 years. These shunts are a good alternative for patients being considered for surgery in whom other portal blood flow preserving procedures (i.e., elective shunts, devascularization with esophageal transection) are not feasible.

A comparative study of the elective treatment of variceal hemorrhage with beta-blockers, transendoscopic sclerotherapy, and surgery: a prospective, controlled, and randomized trial during 10 years.

OBJECTIVE: To compare three options for the elective treatment of portal hypertension during a 10-year period. METHODS: Patients included in the trial were 18 to 76 years old, had a history of bleeding portal hypertension, and had undergone no prior treatment. Treatment options were beta-blockers (propranolol), sclerotherapy, and portal blood flow-preserving procedures (selective shunts and the Sugiura-Futagawa operation). RESULTS: A total of 119 patients were included: 40 in the pharmacology group, 46 in the sclerotherapy group,and 33 in the surgical group. The three groups showed no differences in terms of age, Child-Pugh classification, and cause of liver disease. The rebleeding rate was significantly lower in the surgical group than in the other two groups. The rebleeding rate was only 5% in the Child A surgical group, compared with 71% and 68% for the sclerotherapy and pharmacotherapy groups, respectively. Survival was better for the low-risk patients (Child A) in the three groups, but when the three options were compared, no significant difference was found. CONCLUSIONS: Portal blood flow-preserving procedures offer the lowest rebleeding rate in low-risk patients undergoing elective surgery.

Biliary duct injury: partial segment IV resection for intrahepatic reconstruction of biliary lesions.

A technique for intrahepatic reconstruction of the biliary tree after complex high injuries is described. The fundament of the procedure is the removal of a wedge of segment IV at the level of the hilar plate. When the hilar plate is reached and no adequate exposure of the ducts can be obtained, removing a 1 x 1-in wedge of segment IV between the gallbladder bed and the round ligament exposes the left and right ducts. An anteroposterior view of the plate is obtained instead of a caudocephalic dissection, exposing healthy, nonscarred ducts for reconstruction. We have used this approach in 22 patients, and adequate exposure of the ducts has been obtained, with a high success rate of patency of the anastomosis at a mean follow-up of 3 years. Twenty patients have a patent anastomosis, with a good quality of life and no restenosis.

Determination of miconazole in pharmaceutical creams using internal standard and second derivative spectrophotometry.

A simple method is proposed for miconazole determination in pharmaceutical creams, based on extraction and second derivative spectrophotometry. In the presence of sodium lauryl sulfate (0.5%) and sulphuric acid (0.4 mol l(-1)), the miconazole and internal standard (IS) (methylene blue) were extracted to 100 microl of methylene chloride. The organic phase was evaporated in the nitrogen stream and the dry residue was dissolved in methanol (1.5 ml). The analytical signal was obtained as the ratio between second derivative absorbances measured at 236.9 nm (miconazole) and at 663.2 nm (IS). The use of IS in such multi-stage procedure enabled quite good analytical performance in calibration range 50.0 400 mg l(-1): linear correlation coefficient 0.9995, precision (measured as CV for ten replicates) at 50.0 mg l(-1) and at 400 mg l(-1) of miconazole was 1.5 and 0.5% respectively. Four commercial pharmaceutical creams were analyzed and the results obtained were in good agreement with the results obtained by reversed-phase high performance liquid chromatography (HPLC).

Detection of Onchocerca volvulus DNA in pools of wild-caught Simulium ochraceum by use of the polymerase chain reaction.

The presence of Onchocerca volvulus DNA in experimentally infected flies can now be detected by use of the PCR, so that, for example, one infected Simulium damnosum can be detected in a pool of 100 uninfected flies or one S. ochraceum can be detected in pools of 20-40. As this PCR technique is specific for O. volvulus, the results are not confounded by the presence of other, unimportant, Onchocerca species, and the technique could replace time-consuming, manual dissection of flies. In 1996 and 1997, pools of 16-21 Simulium ochraceum were tested by the PCR technique. These flies had been collected biting man, between 1992 and 1994, from two hyperendemic coffee estates (fincas) in Guatemala, and stored in commercial (95%) ethanol. Collections at finca Buena Vista (869 flies in 52 pools) were made 1-2 weeks and 46 weeks after 45% of eligible subjects had been treated with ivermectin for the first time. At finca El Brote, collections (360 flies in 18 pools) were made 13 weeks before and 7 weeks after 97% of eligible subjects had received their first treatment. DNA was easily recovered from simuliids that had been stored in ethanol for up to 4 years. Of the nine pools of flies with visible blood collected at Buena Vista, each of 20 flies, eight tested positive for O. volvulus DNA. In flies without blood, 13 of 22 pools collected at Buena Vista just after treatment tested positive, whereas there were 14 positives in 22 pools taken 46 weeks later (P > 0.05). At El Brote, nine of 10 pre-treatment pools were positive, compared with three of eight taken 7 weeks post-treatment (P = 0.04), indicating that the treatments in this finca had reduced infection in the vector, and possibly transmission, by about 60%. A sub-sample of Buena Vista flies was divided into 19 sets of three separate sub-pools containing heads, thoraces and abdomens. Three pools of heads alone were positive, and had corresponding pools of positive abdomens. Three positive pools of thoraces had negative corresponding pools of heads and abdomens. These results show that PCR can be used to determine the prevalence of O. volvulus DNA in wild-caught S. ochraceum. As the infection rates observed were higher than expected from dissections reported by other workers, PCR-determined rates may not be directly comparable with traditional parameters based on the dissection of flies to reveal O. volvulus larvae.

Application of the bivariate spectrophotometric method for the determination of metronidazole, furazolidone and di-iodohydroxyquinoline in pharmaceutical formulations.

The bivariate calibration algorithm was applied to the spectrophotometric determination of metronidazole, furazolidone and di-iodohydroxyquinoline in pharmaceutical dosage forms. The results obtained were compared with the results of derivative spectrophotometry. The statistical evaluation of method bias was carried out, and it was shown that the proposed procedure may be competitive with commonly used first-derivative spectrophotometry. The advantage of the bivariate calibration is its simplicity, and the fact that there is no need to use the derivatization procedures.

Assessment of vector microfilarial uptake as a comparatively non-invasive technique for monitoring onchocerciasis treatment campaigns in the Americas.

Since 1992, efforts have been made to combat onchocerciasis in Guatemala through mass distribution of ivermectin. The impact of the campaign is assessed by taking skin-snips from sentinel groups within selected communities. This method gives an estimate of the prevalence and intensity of infection, and thus the efficacy of the treatment. In some communities people are becoming reluctant to volunteer for skin-snipping, and so there is a need for an alternative technique that will give quantitative results. In most hyperendemic communities in Guatemala, biting blackflies are so ubiquitous that few people object to allowing 10 to 20 flies to engorge upon them. We examined data on the quantitative uptake of microfilariae by Simulium ochraceum before and after ivermectin distribution to see whether results similar to skin-snip data could be obtained. Counts of microfilariae ingested by S. ochraceum are compared to the numbers found in skin-snips from the same volunteers. In a group of 31 untreated infected persons, a skin-snip survey detected 64.5% positive, while feeding flies (vector microfilarial uptake, VmfU) detected 96.8%. Post-treatment, in a sample of 58 of whom 52 (89.7%) had a history of infection, both skin-snips and VmfU detected 54.2%. Vector blood meals contained more microfilariae than a mg of skin before treatment, but both recorded about equal numbers after treatment. When the data set was subdivided to compare samples taken at 2-3, 6-8 and 14-17 months post-treatment, the effect of ivermectin was still apparent at 6-8 months, but had virtually disappeared by 14 months post-treatment. A surprising observation was that the flies ingested fewer microfilariae from treated persons than was expected from the skin densities as estimated by skin-snip. This effect lasted for over 8 months, and could indicate that ivermectin has a greater effect on transmission than previously suspected. We conclude that VmfU could be used as an alternative to skin-snipping, and discuss the ethical implications.

Enhanced spectrophotometric determination of chromium (VI) with diphenylcarbazide using internal standard and derivative spectrophotometry.

In the present work, erioglaucine A was applied as internal standard to enhanced spectrophotometric determination of chromium (VI) with diphenylcarbazide. The following procedure was used: (1) addition of internal standard and formation of ion pairs of Cr (VI) with benzyltributylammonium bromide (BTAB) (sample volume 100 ml), (2) extraction to 10 ml of methylene chloride, (3) evaporation in nitrogen stream, and (4) redissolution in a micro-volume with addition of diphenylcarbazide for color development (final volume 200 mul). The preconcentration factor achieved was about 400 and it was shown that, using internal standard, the analytical errors due to sample treatment were reduced. The analytical signals for chromium and internal standard were obtained at 591.30 and 653.50 nm from first derivative spectra, normalized against (1)D(653.50nm). The analytical characteristics evaluated were: detection limit = 0.06 mug l(-1), quantification limit = 0.19 mug l(-1), precision for 1 mug l(-1) 14.2%, and for 10 mug l(-1) 3.2%, correlation coefficient of linear regression was 0.9985. The proposed procedure was applied to determination of chromium (VI) in tap water. Total chromium was determined by electrothermal atomic absorption spectrometry, the recovery of hexavalent chromium added was then evaluated and compared with the results of the proposed procedure. In this experiment, good agreement was obtained between results obtained by the two methods.

Application of internal standard for derivative-spectrophotometric determination of azinphos-methyl in commercial formulations.

The use of an internal standard is proposed in this work for first derivative spectrophotometric determination of azinphos in formulations. Generally, the spectrophotometric procedure is simpler and less expensive than chromatographic techniques recommended for the analysis of pesticides. However, while determining the pesticide in commercial formulations the, many-fold dilution required for such sensitive detection is a serious source of analytical error. It is known that an internal standard (IS), if properly chosen, can help eliminate this type of problem. A mixture of acetophenone (used as an IS in the high performance liquid chromatography (HPLC) procedure) and the blue dye Erioglaucine (A) was applied for the determination of azinphos-methyl in commercial formulations. To ensure the best conditions for the zero-crossing technique, the composition of the mixture was optimized to obtain the zero value of the first derivative absorbance of the IS at a minimum of the azinphos-methyl first derivative absorbance. Also, at the maximum of the first derivative spectrum of the IS, the differential absorption signal of the analyte was negligible. Analytical characteristics for the first derivative spectrophotometric procedure proposed were evaluated (r(2) = 0.9998, detection limit = 0.043 mg, quantification limit = 0.143 mg) and the analytical results obtained (35.02 +/- 0.20% of azinphos-methyl in the formulation) were in good agreement with the results obtained using the official HPLC method (35.44 +/- 0.32%).