Revising the role of pH and thermal treatments in aflatoxin content reduction during the tortilla and deep frying processes

Naturally aflatoxin-contaminated corn (Zea mays L.) was made into tortillas, tortilla chips, and corn chips by the traditional and commercial alkaline cooking processes. The traditional nixtamalization (alkaline-cooking) process involved cooking and steeping the corn, whereas the commercial nixtamalization process only steeps the corn in a hot alkaline solution (initially boiling). A pilot plant that includes the cooker, stone grinder, celorio cutter, and oven was used for the experiments. The traditional process eliminated 51.7, 84.5, and 78.8% of the aflatoxins content in tortilla, tortilla chips, and corn chips, respectively. The commercial process was less effective: it removed 29.5, 71.2, and 71.2 of the aflatoxin in the same products. Intermediate and final products did not reach a high enough pH to allow permanent aflatoxin reduction during thermal processing. The cooking or steeping liquor (nejayote) is the only component of the system with a sufficiently high pH (10.2-10.7) to allow modification and detoxification of aflatoxins present in the corn grain. The importance of removal of tip, pericarp, and germ during nixtamalization for aflatoxin reduction in tortilla is evident.

Airborne outbreak of nosocomial Scedosporium prolificans infection

We describe six inpatients with acute non-lymphocytic leukaemia who developed invasive infection with Scedosporium prolificans resistant to amphotericin B, flucytosine, ketoconazole, fluconazole, and itraconazole. All six patients died. Phenotypic and genotypic assessment of samples from clinical material and ambient air from the isolation rooms where the patients were being treated showed that the epidemic was caused by a single strain. After implementation of aerial control measures, there were no further infections with this organism. We conclude that fatal multidrug-resistant S prolificans epidemics can be aerially transmitted and can be prevented with implementation of appropriate infection-control measures.

Supervisors' tactics of influence and subordinates' tolerance for disagreement

Self-reported scores of 156 subordinates on tolerance for disagreement were associated with their perceptions of supervisors' use of referent, expertise, and reward-based tactics and less use of legitimate and punishment-based tactics of influence.

Time-frequency analysis of arterial pressure oscillations in anesthetized dogs: effects of standardized hemorrhages

The purpose of this preliminary study was to investigate the advantages of the time-frequency analysis through the Continuous Wavelet Transform (CWT) compared to classical Fourier analysis using the Fast Fourier Transform (FFT) in arterial pressure signals from anesthetized mongrel dogs before and during standardized hemorrhages. Systemic arterial pressure pulsations were recorded using catheter-tip manometers. CWT and FFT were applied to arterial pressure pulsations to obtain module coefficients of this transformation and its associated contours during the evolution of progressive hemorrhages, in amounts of 15, 34, and 66% of the estimated total blood volume. This mathematical analysis enabled us to identify the evolution of the frequency components of aortic valve functions, heart dynamics, respiratory influences, and vasomotor activities. Furthermore, we isolated the modulating signal of amplitude modulation phenomenon present in the arterial pressure records, as described in previous papers, being the heart rate carrier frequency. The CWT is a very sensitive and reliable procedure to analyze (time-frequency) the oscillatory phenomena in two dimensions, and to provide more information than the FFT. This new analytical procedure may provide new insights in the study of shock pathophysiology.

Domestic sewage treatment in a pilot system composed of UASB and SBR reactors

The results obtained from the operation of a treatment system composed of an anaerobic (up-flow sludge blanket-UASB) reactor followed by an aerobic (sequencing batch-SBR) reactor treating domestic sewage are presented and discussed. The pilot plant was monitored during 6 months, aiming to obtain performance data on organic matter, nitrogen and phosphate removal under different operating conditions. The UASB reactor was operated at a constant hydraulic detention time (0) of 6 h while the SBR performance was monitored in four different duration cycles (24, 12, 6 and 4 h) corresponding to aeration times (AT) of 22, 10, 4 and 2 h, respectively. COD and TSS overall removal efficiencies (Eo) up to 91% and 84%, respectively, were achieved independently on the aeration time applied to the SBR. In respect to nitrification and phosphate removal, AT was found to be a determining operating parameter. TKN removal of approximately 90% was achieved for AT equal to or higher than 10 h; complete nitrification occurred for AT higher than 4 h; significant phosphate removal (72%) occurred only at the AT of 2 h. It was not possible to achieve simultaneous efficient removal of nitrogen and phosphate, under the operating conditions imposed on the treatment system.

[First description of concomitant infection with tuberculosis and paratuberculosis in dairy sheep in Argentina]

The authors present the results of a comparative intradermal tuberculin test performed on dairy sheep to determine rates of reaction to bovine and avian purified protein derivative (PPD). Test reactions were interpreted by palpation and measurement with a calliper. Results were analysed by plotting the values obtained. Agar gel immunodiffusion tests, growth in culture and histopathological examinations were also performed to allow differential diagnosis between tuberculosis and paratuberculosis. In the first tuberculin test, performed on 288 sheep, 74 animals showed a positive reaction to avian PPD (25.69%), two animals showed a positive reaction to bovine PPD (0.69%), and one animal was positive with respect to both tuberculins (0.34%). In the second test, involving 247 sheep, 55 demonstrated a positive reaction to avian PPD (22.26%), whilst none reacted to bovine PPD. The presence of Mycobacterium avium subsp. paratuberculosis was confirmed by culture and serological testing. In addition, lesions compatible with those caused by M. bovis were found by histopathological examination. These findings highlight the importance of the accurate diagnosis of tuberculosis and paratuberculosis for the effective control of both diseases.

[Cultural characteristics of some ectomycorrhizal fungi in pure culture]

Macro and microscopic features for 21 species of ectomycorrhizal fungi are presented, with regard to their particular importance as possible taxonomic criteria. The culture media used are MMN and BAF. Cultural characteristics of some of our isolates, like color or morphology of the mycelia, were comparable to those observed by different authors for the same species, or species which are closely related taxonomically, as for example Boletus satanas and Lactarius deliciosus in BAF media, or Hebeloma edurum, Lycoperdon perlatum, Paxillus atrotomentosus, Rhizopogon roseolus and Suillus collinitus in MMN media. Macroscopically the color of mycelia, the amount of aerial mycelia and microscopically the exudates and the presence of inflated and flexuous cells were the most variable characteristics within species.

Granulocyte-colony stimulating factor (G-CSF) may improve disease outcome in elderly patients with diffuse large cell lymphoma (DLCL) treated with CHOP chemotherapy

Advanced age is an adverse prognostic factor in patients with DLCL. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) has frequent dose-limiting toxicities, including myelosuppression. We retrospectively reviewed 50 consecutive patients > 60 years of age (median age 72) with B-cell DLCL who received CHOP with G-CSF. Patients received CHOP (median 6 cycles) at three-week intervals. G-CSF was given following all cycles of chemotherapy ("prophylactic G-CSF") in 28 of 50 patients, and following an episode of febrile neutropenia and thereafter in 19 patients, according to ASCO guidelines. Dose intensity, treatment delays, episodes of febrile neutropenia, complete response (CR) rate, disease-free survival, time-to-treatment failure, and overall survival were all analyzed according to the age-adjusted International Prognostic Index (aaIPI). The actual dose intensity for cyclophosphamide was 225.9 mg/m2/week and 0.90, respectively and for doxorubicin was 14.9 mg/m2/week (90% of ideal CHOP dosing for both drugs). Median followup was 4 years for the patients still living. Treatment delays and episodes of febrile neutropenia were less frequent among patients receiving G-CSF with all cycles of CHOP. The CR rates were 100%, 81%, 85%, and 36% for the low, low-intermediate, high-intermediate, and high aalPI risk groups, respectively. The 5-year actuarial relapse-free and overall survival for our patients were comparable to that of the cohort < or = 60 years of age and superior to the > 60 years of age cohort used to establish the aaIPI. With optimization of CHOP dosing, advanced age may not be an adverse prognostic factor for patients with DLCL. The routine use of G-CSF in elderly patients with DLCL should be further investigated.

Coumarins from Ferulago capillaris and F. brachyloba

Four new coumarins, (+)-senecioylprangol, (-)-3'-senecioyloxymarmesin, (+)-3'-hydroxyprantschimgin and (+)-2"-senecioyloxymarmesin, besides 12 known coumarins have been isolated from two Ferulago species. Their structures have been established by spectroscopic methods and partial synthesis. New synthetic 3'-oxocoumarins are also described. There is a remarkable difference in the contents of the most abundant coumarins found in the roots of both species: osthol and aurapten are specific to F. capillaris and F. brachyloba, respectively.

Penetrating craniocerebral injury from an underwater fishing harpoon

Weapon injuries other than gunshot wounds or low-velocity stab wounds to the head are extremely rare. We report the case of a 6-year-old girl who sustained a penetrating craniocerebral injury after being accidentally shot with an underwater fishing harpoon. This mechanism of injury seems to share characteristics of both high- and low-velocity projectiles. We discuss the management of this unusual injury in a child, remarking that foreign body removal in these cases must be carried out following the original direction of the projectile trajectory. We review the current literature on craniocerebral injuries caused by similar objects, especially those occurring in children.

Secondary metabolites from Senecio minutus and Senecio boissieri: a new jacaranone derivative

Jacaranone (1), the related new dimethoxy derivative 2, and known triterpenoids were isolated from the aerial parts of Senecio minutus. The aerial parts and the rhizomes of Senecio boissieri afforded the furanoeremophilanes 3 and 4 and known triterpenoids.

[Parasitic helminths infection in Coho salmón, Oncorhynchus kisutch, during their return to Simpson river, Chile]

Between may and july 1994, 17 adult returning salmons, Oncorhynchus kisutch, were collected in the River Simpson, Chile. All fishes showed infection by plerocercoids of Diphyllobothrium sp. in different locations: stomach, spleen, liver, mesenteries and gonads. Infection with larval cestodes of an unidentified species of Phillobothriidae was determined in the intestine of seven (41.2%) salmons and its prevalences of infection showed significant differences between female and male salmons. The 94.4% of total plerocercoids of Diphyllobothrium were isolated from the stomach wall. Prevalence and mean intensity of infection by Diphyllobothrium sp. did not show significant differences between fishes of different sex.

Pressure oscillations in anesthetized dogs and its conversion into quasi-periodic orbits

Using a basic representation of dynamic systems, arterial blood pressure pulsation is converted into quasi-periodic orbits with the purpose of transforming a periodic phenomena into a cyclical one by plotting the pressure p(t) versus its first derivative dp/dt. This elementary mathematical procedure made it possible to evaluate the variability of the systemic arterial pressure pulsations, both systolic and diastolic, as well as the slope variability of the anachrotic and catachrotic phases. Two periods, which can be used to estimate different sources of variability, can be distinguished in the catachrotic phase. One corresponds to the open aortic valves, and the other is associated with the closed valves. Furthermore, through the first derivative of pressure oscillations we were able to identify small changes in arterial pressure, which appeared when the sampling rate was at least 150 samples per second. Since the time variable was converted into a parameter, the result was a synoptic or holistic approach, which is a considerable improvement for the visual analysis of cardiovascular phenomena. This simplified mathematical procedure can be easily implemented on a personal computer in real time and applied to all rhythmic phenomena in Physiology and Pathology.

Photovoltaic technology: the case for thin-film solar cells

The advantages and limitations of photovoltaic solar modules for energy generation are reviewed with their operation principles and physical efficiency limits. Although the main materials currently used or investigated and the associated fabrication technologies are individually described, emphasis is on silicon-based solar cells. Wafer-based crystalline silicon solar modules dominate in terms of production, but amorphous silicon solar cells have the potential to undercut costs owing, for example, to the roll-to-roll production possibilities for modules. Recent developments suggest that thin-film crystalline silicon (especially microcrystalline silicon) is becoming a prime candidate for future photovoltaics.

Evaluation by Vickers indentation of fracture toughness of a phosphate biodegradable glass

Indentation tests are commonly used for the evaluation of fracture toughness of brittle materials, particularly glasses and ceramics, because this technique requires only a small polished area on the specimen surface from which a large number of data points can be generated rapidly. However, a wide variety of equations for the calculation of fracture toughness of ceramic materials by means of Vickers indentation are available. Such equations are obtained phenomenologically and their parameters adjusted in such a way that the KIC values obtained are in good agreement with those obtained by conventional methods. This is the reason why it is necessary to check which type of equation reproduces more accurately the results obtained by means of conventional methods for the material which is going to be investigated. In the present work seven different fracture toughness equations widely used in glass and ceramic studies are considered and the results are compared with those obtained by conventional methods, such as single-edge notch beam (SENB) specimens tested in three-point bending. The role played by the applied indentation load is considered.

Acanthocolpid metacercariae in the sea bass from Alejandro Selkirk Island, Chile

Morphological characteristics of a metacercaria from muscle of 15 sea bass Caprodon longimanus (Serranidae) collected near Alejandro Selkirk Island (Chile) in the south-eastern Pacific Ocean indicate that it belongs to the genus Manteria (Acanthocolpidae). All metacercarie were encapsulated with connective tissue. The prevalence of infection was 100%, with 64% of metacercariae were located between dorsal pterygiophores and dorsal fin base. Mean intensities of metacercariae did not differ significantly with respect to sex of the fish. There was no significant correlation with intensities of infection and condition in the host.

On a new species of Hysterothylacium (Nematoda: Anisakidae) from Cauque mauleanum (Pisces: Atherinidae) by brightfield and scanning electron microscopy

Hysterothylacium geschei n. sp. (Nematoda, Anisakidae) is described from the intestine of Cauque mauleanum (Steindachner) (Pisces: Atherinidae) from Lake Panguipulli (39 degrees-43'S; 72 degrees-13'W), Chile. Eleven (78.6%) out of 14 fish were infected, with a mean intensity (range) of 14.4 (1-55) worms. The new species can be differentiated from the two previously described species of freshwater fishes from South America by the presence of lateral alae, the number of caudal papillae, and the length of the spicules, oesophagus, intestinal caecum, distance vulva-anterior extremity and the length ratio intestinal caecum: ventricular appendix. From the fishes examined in Lake Panguipulli, including the introduced salmonid species Oncorhynchus mykiss (Walbaum) and the authochthonous species Basilichthys australis Eigenmann (Atherinidae) and Percichthys trucha (Valenciennes) (Percichthyidae), only one specimen of P. trucha was found parasitized by a third-stage larva of this species.