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The principal desirable characteristics of the yeasts used in order to maintain the yield and the efficiency high during the process of ethanol production are mainly thermotolerance, Killer activity and high resistance to inhibitor compounds like acetic acid. Yeast represents the most important factor to achieve an efficient conversion process of the different raw materials used to produce ethanol like sorghum and sugarcane juice or their lignocellulosic materials. The aim of this work was to isolate and select native yeasts from sweet sorghum juice with thermotolerance and resistance to toxic compounds like acetic acid, furfural and 5-hydroxymethylfurfural, capable of producing high ethanol concentrations. The results obtained showed that native yeast Pichia kudriavzevii ITV-S42 exhibit thermotolerance at 40 °C, positive Killer activity, tolerant to acetic acid up to 24 g/L initial concentration, and tolerant to furfural and 5-hydroxymethylfurfural up to 1 g/L for both compounds. An ethanol productivity and yield of 0.54 g/Lh and 0.376 g ethanol/g glucose, respectively, were obtained. These results show that the desirable characteristics of Pichia kudriavzevii ITV-S42 could be interesting for their implementation in first and second generation ethanol process production. [ABSTRACT FROM AUTHOR]

Stabilization and solidification mixtures of contaminated material with 60% weathered, oily crust, and 40% sediment were made, and acute toxicity (Vibrio fischeri bioassay), hydrocarbons in leachates, and resistance to compression were determined. For stabilized materials, the hydrocarbon concentration expected in base soil (underneath stabilization cells) was calculated from hydrocarbon concentrations in laboratory leachates using a modified test that better simulates real site conditions (acid extraction of complete formed blocks). In the modified tests, an asymptotic behavior in the hydrocarbon concentration in leachates was observed, nearing a maximum after 15 days. The calculated hydrocarbon concentration in base soil was < 3000 mg/Kg in all concentrations of agglomerate and pozzolan used (3.75–15% CaO, 1.25–5.0% diatomaceous earth). Acute toxicity was null or indeterminate with respect to background levels. For solidified materials, in two of the treatments (3.75 and 7.5% CaO, 1.25 and 3.75% diatomaceous earth; plus gravelly backfill at 1:1), unconfined resistance to compression was sufficient for the material to be used as sub-base for rural roads (> 17.6 ton/m2), but with higher concentrations of reagents (15% CaO, 5% diatomaceous earth; plus gravelly backfill at 1:1), the resistance was insufficient. In all solidification treatments, no toxicity above background was encountered, and Total Petroleum Hydrocarbons in leachate tests resulted in calculated hydrocarbon concentrations in base soil of < 3000 mg/Kg. From these data, it was concluded that stabilization and solidification were feasible for this site using low concentrations of reagents, and that it was not necessary to use a plastic liner to prevent subsoil contamination. [ABSTRACT FROM AUTHOR]

The incidence of Pneumocystis jirovecii pneumonia (PJP) has increased over recent years in patients with systemic autoimmune rheumatic diseases (SARD). PJP prognosis is poor in those receiving immunosuppressive therapy and glucocorticoids in particular. Despite the effectiveness of cotrimoxazole against PJP, the risk of adverse effects remains significant, and no consensus has emerged regarding the need for PJP prophylaxis in SARD patients undergoing immunosuppressor therapies.Objective: To evaluate the efficacy and safety of cotrimoxazole prophylaxis against PJP in SARD adult patients receiving immunosuppressive therapies. Methods: We performed a systematic review, consulting MEDLINE, EMBASE, and Cochrane Library databases up to April 2020. Outcomes covered prevention of PJP, other infections, morbidity, mortality, and safety. The information obtained was summarized with a narrative review and results were tabulated. Of the 318 identified references, 8 were included. Two were randomized controlled trials and six observational studies. The quality of studies was moderate or low. Despite disparities in the cotrimoxazole prophylaxis regimens described, results were consistent in terms of efficacy, particularly with glucocorticoid doses > 20 mg/day. However, cotrimoxazole 400 mg/80 mg/day, prescribed three times/ week, or 200 mg/40 mg/day or in dose escalation, exhibited similar positive performances. Conversely, cotrimoxazole 400 mg/80 mg/day showed higher incidences of withdrawals and adverse effects. Cotrimoxazole prophylaxis against PJP exhibited efficacy in SARD, mainly in patients taking glucocorticoids ≥ 20 mg/day. All cotrimoxazole regimens exposed seemed equally efficacious, although, higher quality trials are needed. Adverse effects were observed 2 months after initiation, particularly with the 400 mg/80 mg/day regimen. Conversely, escalation dosing or 200 mg/40 mg/day regimens appeared better tolerated. [ABSTRACT FROM AUTHOR]

Direct current (DC) and Alternating current (AC) electrochemical techniques were used to evaluate 304L SS with hydrothermal deposits of nanoparticles of TiO2 (anatase and rutile phases) and ZrO2 (baddeleyite phase) in ultra-high pure water at 288°C and 8 MPa. The deposits were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). ZrO2 and TiO2 increase the charge transfer resistance, whereas the corrosion potential of 304L SS is slightly higher in the presence of nanodeposits. A different electrochemical kinetic mechanism was found for each nanodeposit. The TiO2 anatase nanodeposit induces an oxide layer different from the characteristic one formed on 304L SS under the studied conditions. Nanoparticles of anatase promoted the formation of a chromium-rich oxide on 304L SS at 288°C and 8 MPa, whereas, hydrothermal deposit of nanoparticles of rutile TiO2 or baddeleyite ZrO2 did not produced such effect on the composition of the iron-rich oxide layer present on 304L SS, which explain the different electrochemical behavior found in presence of each nanodeposit. [ABSTRACT FROM AUTHOR]

Environmental variability often results in morphological plasticity, allowing organisms to acclimate and resist changing environmental conditions. Corals exhibit high morphological variability, possibly influenced by factors such as phenotypic plasticity and hybridization. Pseudodiploria Fukami, Budd & Knowlton, 2012 consists of two species, Pseudodiploria strigosa Dana, 1846 and Pseudodiploria clivosa Ellis & Solander, 1786, which are often differentiated by the colony morphology, number of septa per centimeter, width of valleys, and the presence/absence of coenosteum. In this study, we performed morphological and molecular analyses of 40 Pseudodiploria colonies (20 samples each reef) from the Gulf of Mexico in two reefs Gallega (coastal reef) and Galleguilla (at 2 km of coastline), at the Veracruz Reef System, using univariate analyses of 14 macro- and micro-characters supplemented by examination of mitochondrial (cytochrome b) and nuclear (β-tubulin) sequences. We confirmed the presence of the two Pseudodiploria species based on micro-morphological results. However, 32 colonies of Pseudodiploria presented high phenotypic plasticity at colony and calice levels (11 of the 14 evaluated characters), and molecular variation of β-tubulin gene was higher in the colonies that exhibited high morphological variability. Genetic distances of β-tubulin gene sequences also demonstrated that all colonies collected are most similar to P. clivosa (according to previous studies). Interestingly, we found that colonies collected from a coastal reef had higher variability in morphological characters at colony and calice levels (17 of 20 samples), which may be the evidence of the effect of environmental conditions on phenotypic plasticity of Pseudodiploria colonies. [ABSTRACT FROM AUTHOR]

B cell-activating factor (BAFF) promotes the survival, proliferation and maturation of B lymphocytes, which are key elements in the pathogenesis of systemic lupus erythematosus (SLE). This cytokine is encoded on TNFSF13B gene, and diverse single-nucleotide polymorphisms have been associated with susceptibility in different autoimmune disorders. In this study, the relationship of TNFSF13B gene rs9514827T>C, rs1041567T>A and rs9514828C>T polymorphisms, mRNA expression and soluble BAFF levels was investigated in 175 SLE patients and 208 healthy controls (HC). The TNFSF13B polymorphisms were evaluated by PCR–RFLP technique. The TNFSF13B gene expression was quantified through the RT-PCR assays. The soluble BAFF (sBAFF) levels were measured with ELISA test. There were no differences in genotype and allele frequencies for the three TNFSF13B polymorphisms, between SLE patients and HC. SLE patients showed 3.15-fold more TNFSF13B gene expression than HC. The patients who displayed most mRNA expression were those with active disease and the carriers of rs9514828 T variant allele. The sBAFF serum levels were higher in SLE patients compared to HC (2.083 vs. 0.742 ng/mL, p < 0.001). The SLE patients with active disease showed the higher sBAFF serum levels (2.403 ng/mL), mainly patients with lupus nephritis and hematological manifestations. In addition, a correlation of sBAFF with disease activity was found (r = 0.32, p < 0.001). In conclusion, the TNFSF13B gene polymorphisms were not found to be associated with SLE susceptibility in Mexican mestizos. Nevertheless, rs9514828C>T polymorphism seems to increase TNFSF13B gene expression. High BAFF expression is related to active disease, renal and hematological involvement; therefore, it could be considered as follow-up biomarker in SLE patients. [ABSTRACT FROM AUTHOR]

Spinocerebellar ataxia type 7 is a neurodegenerative inherited disease caused by a CAG expansion in the coding region of the ATXN7 gene, which results in the synthesis of polyglutamine-containing ataxin-7. Expression of mutant ataxin-7 disturbs different cell processes, including transcriptional regulation, protein conformation and clearance, autophagy, and glutamate transport; however, mechanisms underlying neurodegeneration in SCA7 are still unknown. Implication of oxidative stress in the pathogenesis of various neurodegenerative diseases, including polyglutamine disorders, has recently emerged. We perform a cross-sectional study to determine for the first time pheripheral levels of different oxidative stress markers in 29 SCA7 patients and 28 age- and sex-matched healthy subjects. Patients with SCA7 exhibit oxidative damage to lipids (high levels of lipid hydroperoxides and malondialdehyde) and proteins (elevated levels of advanced oxidation protein products and protein carbonyls). Furthermore, SCA7 patients showed enhanced activity of various anti-oxidant enzymes (glutathione reductase, glutathione peroxidase, and paraoxonase) as well as increased total anti-oxidant capacity, which suggest that activation of the antioxidant defense system might occur to counteract oxidant damage. Strikingly, we found positive correlation between some altered oxidative stress markers and disease severity, as determined by different clinical scales, with early-onset patients showing a more severe disturbance of the redox system than adult-onset patients. In summay, our results suggest that oxidative stress might contribute to SCA7 pathogenesis. Furthermore, oxidative stress biomarkers that were found relevant to SCA7 in this study could be useful to follow disease progression and monitor therapeutic intervention. [ABSTRACT FROM AUTHOR]

A new method for obtaining optimal polygonal approximations in closed curves is proposed. The new method uses the suboptimal method proposed by Pikaz and an improved version of the optimal method proposed by Salotti. Firstly, the Pikaz's method obtains a suboptimal polygonal approximation and then the improved Salotti's method is used for obtaining many local optimal polygonal approximations with a prefixed starting point. The error value obtained in each polygonal approximation is used as value of pruning to obtain the next polygonal approximation. In order to select the starting point used by the Salotti's method, five procedures have been tested. Tests have shown that by obtaining a small number of polygonal approximations, global optimal polygonal approximation is calculated. The results show that the computation time is significantly reduced, compared with existing methods. [ABSTRACT FROM AUTHOR]

Sweet sorghum ( Sorghum bicolor (L.) Moench) bagasse is a lignocellulosic material consisting mainly of hemicellulose and cellulose, a potential source of fermentable sugars. The present study aimed to optimize the hydrolysis of sweet sorghum bagasse to obtain the highest concentrations of xylose and glucose with the minimum amount of inhibitor compounds. Seven varieties of sweet sorghum bagasse were used for the hydrolysis experiment, carried out in three stages with a 2 Box-Behnken factorial design; the critical factors selected for both stages were HSO and HO concentrations, time and liquid-solid ratio (LSR). The alkaline hydrolysis was carried out with a subsequent enzymatic hydrolysis using 0.4 mL cellulose and 0.5 mL beta-glucosidase. The optimum conditions for acid hydrolysis were HSO (1.375 % w/v), time (36 min) and LSR (4.9:1 v/w of bagasse) resulting in values of 11.55 g/L glucose and 41.27 g/L xylose, respectively; for alkaline hydrolysis HO (4.5 % w/v), time (45 h) and LSR (16:1 v/w of bagasse) were the optimum values. Under these conditions, 65.96 g/L glucose concentration was obtained. Validation of the model indicated no difference between predicted and observed values in the optimization of the hydrolysis process. [ABSTRACT FROM AUTHOR]

Summary: Hip fractures (HF) are prevalent and involve high morbidity and mortality so improving their management is important. HF registries are a good way to improve knowledge about this condition and its quality of care, while at the same time reducing clinical variability, optimizing efficiency, improving outcomes, and reducing costs. Introduction: Hip fractures (HF) are a prevalent fragility fracture secondary to osteoporosis that involves high morbidity and mortality. They are low-impact fractures, resulting from a fall from a standing or sitting height. Despite numerous Clinical Practice Guidelines that establish uniform recommendations for their care, great variability persists regarding clinical and healthcare outcomes. Fracture registries can help detect deficits and establish measures to improve care. The objective of this work is to analyze the contents that a HF registry should have and to compare the characteristics of some national HF registries. Methods: A literature search was conducted on several national hip fracture registries, and those that contain relevant information on the variables and their outcomes were selected. Results: The selected HF registries were compared using the parameters they measure as well as the outcomes in the different countries. The variables collected in the majority of the databases and those that give useful information are as follows: sociodemographic variables (age, sex, place of residence), clinical variables (function before and after HF, anesthesia risk as measured by the ASA score, type of fracture, type of surgery and anesthesia, and in-hospital and 1-month mortality), and healthcare variables (pre-operative and overall stay, presence of collaboration with orthogeriatrics or with any clinician in addition to the surgeon, secondary prevention of new fractures by assessing the fall risk, and need for osteoporosis treatment). Conclusion: The recording of HF cases in different countries improves knowledge about handling this condition and its quality of care, while at the same time reducing clinical variability, optimizing efficiency, improving outcomes, and reducing costs. The debate on the variables that should be recorded is timely, such as organizing how to collect each measurement, and even trying to unify the national and international registries or using a current proposal such as the one from the Fragility Fracture Network. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of ethylene-releasing (ACC, Ethephon, Methionine) and -inhibiting (cobalt chloride, silver thiosulfate) compounds on ethylene production and shoot organogenesis of nodal segments, where buds were completely removed, from mature tissues of Citrus limon, Fino 49 and Verna 51 cultivars. The addition of ACC to the culture medium produced a very significant decrease of the regeneration. These results were directly related to the ethylene levels measured in the atmosphere inside the tube. Similar results were observed with ethephon and methionine; the gradual increase in ethylene levels in the tubes, with increasing ethylene-releasing compounds in the culture medium, agrees with the decrease in the regeneration rate observed, but the effect was lower than with ACC. When cobalt chloride (CoCl) was added to the culture medium, contrary to what was expected, the regeneration decreased in both cultivars and this decreasing was not related with the increase in ethylene production. These observations matched the occurrence of yellowish necrotic explants increasing the concentration of cobalt chloride, probably because of a toxic effect on lemon explants. The increase of silver thiosulfate (STS) in the culture medium enhanced the regeneration percentage in both Verna 51 and Fino 49 cultivars. Nevertheless, ethylene levels increased proportionally with the STS concentration and the regeneration rate. These results may be explained since the effects produced by the high ethylene levels measured in STS experiments were blocked by Ag ions, thereby increasing the regeneration percentage. Media to which STS was added produced the highest regeneration percentages. The results obtained in this study showed that ethylene plays an important role in the organogenesis of mature explants of C. limon. [ABSTRACT FROM AUTHOR]

In the present study, we introduce affective norms for a new set of Spanish words, the Madrid Affective Database for Spanish (MADS), that were scored on two emotional dimensions (valence and arousal) and on five discrete emotional categories (happiness, anger, sadness, fear, and disgust), as well as on concreteness, by 660 Spanish native speakers. Measures of several objective psycholinguistic variables-grammatical class, word frequency, number of letters, and number of syllables-for the words are also included. We observed high split-half reliabilities for every emotional variable and a strong quadratic relationship between valence and arousal. Additional analyses revealed several associations between the affective dimensions and discrete emotions, as well as with some psycholinguistic variables. This new corpus complements and extends prior databases in Spanish and allows for designing new experiments investigating the influence of affective content in language processing under both dimensional and discrete theoretical conceptions of emotion. These norms can be downloaded as supplemental materials for this article from . [ABSTRACT FROM AUTHOR]

Tetrahymena rostrata, which is characterized by a particular encystment-excystment cycle involving autogamy, has been recently found infecting the kidney of edible Helix aspersa snails under farming conditions. In this work, the effects of several factors on its encystment/excystment behaviour and the occurrence of different serotypes were investigated. The encystment/excystment response under starvation conditions was seriously affected by temperature. While a peak of encystment at 48 h followed by a progressive spontaneous excystment was observed at 18 and 25 °C, the encystment response was practically inhibited at 5 °C and clearly slowed down at 10 °C. At 30 °C, most of surviving ciliates remained encysted throughout the experiment, with spontaneous excystment being detected only after switching the temperature to 18 °C. Soil components also affected the encystment/excystment behaviour at 18 °C, with spontaneous excystment occurring in the presence of a sterile-filtered soil extract or mineral water but being strongly minimized with a non-filtered soil extract. Resting cysts formed in the latter extract exhibited a 3-4 times thicker and ultrastructurally more complex wall than that formed in mineral water and retained the excystment ability for about 4 weeks. Incomplete desiccation did not affect significantly the encystment response, while the mucus and kidney extracts from snails as well as a ciliate extract strongly stimulated a rapid excystment. Finally, two different serotypes infecting H. aspersa in heliciculture farms of Galicia (NW Spain) were identified, but no differences were observed between the encystment/excystment responses exhibited by two isolates belonging to each serotype. [ABSTRACT FROM AUTHOR]

We studied the responses of soil microbial biomass, respiration and enzyme activities to temperature in three Mexican soils. Soils were incubated at temperature range of 15-550 °C at 50 (wet) and 10 % (dry) of their water holding capacity. Soils were assayed for their adenosine triphosphate (ATP) content, CO-C evolution and acid and alkaline phosphomonoesterase, phosphodiesterase, β-glucosidase, urease, and protease activities. Thermal responses of soil enzyme activities were fitted to both the equilibrium model (EM) and the classical Q model to describe the effects of temperature on enzyme activity. Total organic C, Fe speciation, available P, and inorganic N contents were also determined in all soils and at all temperatures. The results showed that the ATP content, CO-C evolution, and enzyme activities of soil increased within the temperature range 15-65 °C, and at higher temperatures, soil enzyme activities were more resistant than the ATP content and CO-C evolution. The effects of temperature were more drastic in wet than in dry soil, although the two soil series displayed similar trends. The enzyme activities showed a good fit to the EM, making this model suitable for determining activation energy, enthalpy of inactivation, and equilibrium inactivation temperatures of soil enzymatic reactions. The results of the EM indicated that soil chemical parameters may not affect the activation energy of enzyme reactions, but may influence the enzyme resistance to inactivation at higher temperature. The results also indicated that the EM model can be used for predicting the impact of high temperatures on soil enzyme activities. [ABSTRACT FROM AUTHOR]

Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration. We recently described one of the largest series of patients with SCA7 that originated from a founder effect in a Mexican population, which allowed us to perform herein the first comprehensive clinical, neurophysiological, and genetic characterization of Mexican patients with SCA7. In this study, 50 patients, categorized into adult or early phenotype, were clinically assessed using standard neurological exams and genotyped using fluorescent PCR and capillary electrophoresis. Patients with SCA7 exhibited the classical phenotype of the disease characterized by cerebellar ataxia and visual loss; however, we reported, for the first time, frontal-executive disorders and altered sensory-motor peripheral neuropathy in these patients. Semiquantitative analysis of ataxia-associated symptoms was performed using Scale for the Assessment and Rating of Ataxia (SARA) and the Brief Ataxia Rating Scale (BARS) scores, while extracerebellar features were measured employing the Inventory of Non-ataxia Symptoms (INAS) scale. Ataxia rating scales confirmed the critical role size of cytosine-adenine-guanine (CAG) repeat size on age at onset and disease severity, while analysis of CAG repeat instability showed that paternal rather than maternal transmission led to greater instability. [ABSTRACT FROM AUTHOR]

The effect of the injection of pure oxygen instead of air in a membrane bioreactor for the elimination of bisphenol A is investigated. A dynamic experiment was developed in a pilot plant where the aerobic reactor was continuously spiked with 1 mg L of bisphenol A. Air was injected for 10 days and then pure oxygen was injected for another 10 days. The bisphenol A concentration was determined in aqueous phases and activated sludge using simple and sensitive analytical methods based on different extraction procedures and liquid chromatography tandem mass spectrometry analysis. Enzymatic activity was also determined and toxicity tests were performed to discard that the spiked bisphenol A concentration could negatively affect the microorganisms in the bioreactor and, thus, the membrane bioreactor performance. The effluent bisphenol A concentration increased up to 0.26 mg L after 4 days in the air injection treatment, and up to 0.48 mg L after only 12 h in the oxygen injection treatment. In both cases, this was followed by a decrease in concentration despite the continuous spiking of bisphenol A into the bioreactor. In presence of pure oxygen, bisphenol A concentration reached background levels (below the limit of quantification) after 5 days. In contrast, when using air a total of 10 days were required to reach background levels. The injection of pure oxygen instead of air is an important innovation in wastewater treatment, allowing permanent elimination of organic contaminants, avoiding their return to the environment and ensuring the safety of water. [ABSTRACT FROM AUTHOR]

FeCo nanoparticles synthesized on sepiolite microparticles were used for the preparation of nanocomposites by melt compounding with polystyrene. Both, the sepiolite fibers and the nanoparticles were free of agglomeration, which allowed preparing nanocomposites with a homogeneous dispersion of the second phases, avoiding the usual agglomeration of the nanoparticles and minimizing light scattering. As a consequence, transparent composites with a high magnetic susceptibility have been obtained. The magneto-optical Faraday activity of these nanocomposites has been studied, finding saturation rotations over 200 rad·m −1 in the visible range. The processing route presented in this work can be easily transferred to industry and allows preparing polymer matrix nanocomposites with no restriction on shape or size and opens the possibility of developing other highly transparent polymer-based nanocomposites. [ABSTRACT FROM AUTHOR]

Spinocerebellar ataxia type 7 (SCA7) is a neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration that leads, in the majority of patients, to loss of autonomy and blindness. The cause of the disease has been identified as (CAG) repeat expansion in the coding sequence of the ATXN7 gene on chromosome 3p21.1. SCA7 is one of the least common genetically verified autosomal dominant cerebellar ataxias found worldwide; however, we previously identified the Mexican population showing high prevalence of SCA7, suggesting the occurrence of a common founder effect. In this study, haplotype analysis using four SCA7 gene-linked markers revealed that all 72 SCA7 carriers studied share a common haplotype, A-254-82-98, for the intragenic marker 3145G/A and centromeric markers D3S1287, D3S1228, and D3S3635, respectively. This multiloci combination is uncommon in healthy relatives and Mexican general population, suggesting that a single ancestral mutation is responsible for all SCA7 cases in this population. Furthermore, genotyping using 17 short tandem repeat markers from the non-recombining region of the Y chromosome and further phylogenetic relationship analysis revealed that Mexican patients possess the Western European ancestry, which might trace the SCA7 ancestral mutation to that world region. [ABSTRACT FROM AUTHOR]

Common snook ( Centropomus undecimalis) is one of the most important marine species under commercial exploitation in the Gulf of Mexico; for this reason, interest in developing its culture is a priority. However, larviculture remains as the main bottleneck for massive production. In this sense, our objective was to determine the changes of digestive enzymes activities using biochemical and electrophoretic techniques during 36 days of Common snook larviculture fed with live preys (microalgae, rotifers, and Artemia). During larviculture, all digestive enzymatic activities were detected with low values since yolk absorption, 2 days after hatching (dah) onwards. However, the maximum values for alkaline protease (6,500 U mg protein), trypsin (0.053 mU × 10 mg protein), and Leucine aminopeptidase (1.4 × 10 mU mg protein) were detected at 12 dah; for chymotrypsin at 25 dah (3.8 × 10 mU mg protein), for carboxypeptidase A (280 mU mg protein) and lipase at 36 dah (480 U mg protein), for α-amylase at 7 dah (1.5 U mg protein), for acid phosphatases at 34 dah (5.5 U mg protein), and finally for alkaline phosphatase at 25 dah (70 U mg protein). The alkaline protease zymogram showed two active bands, the first (26.3 kDa) at 25 dah onwards, and the second (51.6 kDa) at 36 dah. The acid protease zymogram showed two bands (RF = 0.32 and 0.51, respectively) at 34 dah. The digestive enzymatic ontogeny of C. undecimalis is very similar to other strictly marine carnivorous fish, and we suggest that weaning process should be started at 34 dah. [ABSTRACT FROM AUTHOR]

This study compared growth, nodulation, nitrogen fixation, and nodular enzyme activities in response to salinity in some common bean-rhizobia symbiotic combinations. Seeds of Paulista and Efequince, two varieties of the common bean (Phaseolus vulgaris) were germinated and seedlings were transferred to pots containing vermiculite inoculated with the reference Rhizobium strain CIAT899 or with RhM11 or RhM14, two local strains. Plants were grown in a temperature-controlled glasshouse at 28°C and irrigated with a nutrient solution without NaCl (control) or supplemented with 25 mM NaCl (stressed). Plants were harvested at the flowering stage. The results showed that in controls, inoculation with RhM11 improved plant and nodule growth compared with those inoculated with RhM14 and CIAT 899. NaCl treatment generally had a negative affect on plant and nodule growth. Under the saline treatment, symbiotic nitrogen fixation was not significantly affected in the CIAT899-Paulista, CIAT899-Efequince and RhM11-Paulista combinations. Plant mineral nutrition was negatively affected under salt treatment for all of the tested symbiotic combinations. Inoculation with CIAT899 and RhM11 conferred more plant tolerance to salinity than inoculation with RhM14. The nodular phosphoenolpyruvate carboxylase (PEPC) and malate dehydrogenase (MDH) exhibited higher activities and were less affected by salinity in plants inoculated with the reference strain CIAT899 than those inoculated with local strains. We conclude that plants inoculated with CIAT899 and RhM11 showed more salinity stress tolerance than those inoculated with RhM14. [ABSTRACT FROM AUTHOR]

Several samples of P. splendida larvae were obtained from eggs until day 60 after hatching (dah) to determine acid and alkaline proteases, trypsin, chymotrypsin, leucine aminopeptidase, α-amylase, lipase, and acid and alkaline phosphatase activities using biochemical techniques. Additionally, SDS-PAGE alkaline protease zymogram and PAGE acid protease zymogram were carried out to identify active isoforms during larviculture. Alkaline protease and chymotrypsin were present at the moment of hatching, increased gradually reaching the maximum values at 35 dah. Trypsin and leucine aminopeptidase activities were low from hatching, increasing gradually as larvae grew. Alkaline protease zymogram showed four zymogens, which appears at different days, remaining present until the end of the larviculture (95.2 kDa at 11 dah, 26.4 kDa at 9 dah, 21.4 kDa at 3 dah, and 23.3 kDa at hatching). Pepsin activity was present at day 7 after hatching and increased progressively until the end of the larviculture. Acid protease zymogram only showed one zymogen (0.65 rf), which appear at 6 dah. Lipase was high at the time of hatching and increased until 15 dah, after which decreased gradually. Amylase was high from the beginning and until 15 dah and then decreased rapidly to almost nothing onward. Alkaline and acid phosphatases presented a high activity at the egg stage, fell slightly during the first feeding and increased again from 20 to 30 dah. Results obtained in this study show that larvae can be fed artificial diets starting on day 10 after hatching. [ABSTRACT FROM AUTHOR]

The development of digestive enzymes during the early ontogeny of the Mayan cichlid ( Cichlasoma urophthalmus) was studied using biochemical and electrophoretic techniques. From yolk absorption (6 days after hatching: dah), larvae were fed Artemia nauplii until 15 dah, afterward they were fed with commercial microparticulated trout food (45% protein and 16% lipids) from 16 to 60 dah. Several samples were collected including yolk-sac larvae (considered as day 1 after hatching) and specimens up to 60 dah. Most digestive enzymes were present from yolk absorption (5-6 dah), except for the specific acid proteases activity (pepsin-like), which increase rapidly from 8 dah up to 20 dah. Three alkaline proteases isoforms (24.0, 24.8, 84.5 kDa) were detected at 8 dah using SDS-PAGE zymogram, corresponding to trypsin, chymotrypsin and probably leucine aminopeptidase enzymes, and only one isoform was detected (relative electromobility, Rf = 0.54) for acid proteases (pepsin-like) from 3 dah onwards using PAGE zymogram. We concluded that C. urophthamus is a precocious fish with a great capacity to digest all kinds of food items, including artificial diets provided from 13 dah. [ABSTRACT FROM AUTHOR]

Myotonic dystrophy type 1 (DM1), the most common form of adult muscular dystrophy, is caused by anormal expansion of CTG trinucleotide repeats located in the 3′-untranslated region of the DMPK gene. The clinical features of DM1 are multisystemic and highly variable, and the unstable nature of CTG expansion causes wide genotypic and phenotypic presentations. In this study, we described to our knowledge for the first time the molecular diagnosis of myotonic dystrophy type 1 patients in the Mexican population, applying a fluorescent PCR method in combination with capillary electrophoresis analysis of the amplified products. We identified expanded alleles in 45 out of 50 patients (90%) with clinical features of myotonic disease. Furthermore, genotyping of 400 healthy subjects revealed the presence of 25 different alleles, ranging in size from 5 to 34 repeats. The most frequent allele was 13 CTG repeats (38.87%) and the frequency for alleles over 18 CTG repeats was 6.7%. Molecular test is essential for DM1 diagnosis and distribution of the CTG repeat alleles present in the Mexican population are significantly different from those of other populations. [ABSTRACT FROM AUTHOR]

Blubber from stranded South American sea lions ( Otaria flavescens) was sampled between 1991 and 2005 on the Peninsula Valdés in Argentina and analyzed for organochlorine (OC) pollutants. Mean blubber concentrations, expressed on an extractable basis, were 686 (SD = 1,060) ng g−1 for dichlorodiphenyl trichloroethane (tDDT) and 735 (SD = 787) ng g−1 for polychlorinated byphenils (PCB). The OC levels were well below those associated with adverse sublethal effects and lethality in mammals. OC concentrations showed statistically significant associations with age that were positive in males and negative in females. These trends are consistent with the majority of marine mammal populations studied. There were no trends in the levels of tDDT or PCB over time. In spite of the low levels detected, OC contamination was present consistently over the 14-year period, suggesting continuous inputs from geographic redistribution. [ABSTRACT FROM AUTHOR]

Trials were planted at Rio Bravo, Tamaulipas, Mexico, during 2002 and 2003 with the objective of determining the relationship between sorghum ergot severity and weather factors, and to develop a risk assessment model. Six sorghum hybrids and three male-sterile genotypes were planted every month from January to October. At anthesis initiation, inoculation was conducted using a local isolate of Claviceps africana. Among hybrids, there was a negative relationship between ergot severity and maximum and minimum temperatures, with the highest significant correlation of –0.71 from 7 to 9 days before anthesis. During this period, minimum temperatures above 10°C increased the risk of ergot development, whereas minimum temperatures above 22.5°C prevented ergot development. In male-sterile plants, ergot was negatively related to maximum temperature after anthesis, with ergot being observed at maximum temperatures up to 38°C. Minimum relative humidity showed a positive and significant correlation with ergot severity. Values of minimum relative humidity above 30% during anthesis promoted infection. Surface response regression models were developed for the effects of minimum relative humidity and minimum and maximum temperature during the infection process on ergot severity. [ABSTRACT FROM AUTHOR]

The δ-endotoxins (δ-ETX) of four native strains (RT7, RT19, RT25, and RT25), and one reference strain (4L1) of Bacillus thuringiensis were biochemically and molecularly characterized to determine their potential toxic activity against lepidopteran larvae. Crystals of δ-ETX were purified through a two-phase system to determine their morphology, molar mass, solubility, and resistance to proteinases. Toxic activity and cry gene content were also determined. Crystals from native strains exhibited polyhedral, irregular and cuboidal shapes, while those from 4L1 were bipyramidal. Seven proteins with estimated molar mass ≈30–134 kDa were detected as the main components of the native δ-ETX. Only crystals from 4L1, RT24, and RT25 underwend complete solubilization at pH >12.0. Crystals from all strains produced trypsinresistant peptides. None of the cry genes associated with toxicity in lepidopterans ( cry1, cry2, cry9) was found in the native strains; however, 4L1 strain harbors cry1 and cry2 genes. Strains RT19 and RT25 caused significant mortality against Trichoplusia ni larvae with partial solubilization at pH 10, strain 4L1 caused 100 % mortality. Toxicity of native strains may come from a novel cry gene. [ABSTRACT FROM AUTHOR]

Within the BCS theory of superconductivity we calculate the superconducting gap at a zero-temperature for metallic hydrogen–graphene system in order to estimate the superconducting critical temperature of quasi-two-dimensional highly oriented pyrolytic graphite. The obtained results are given as a function of the hydrogen-induced density of carriers n and their effective mass m ⋆. The obtained gap shows a Maxwell-like distribution with a maximum of ∼60 K at n∼3×1014 cm−2 and m ⋆/ m=1. The theoretical results are discussed taking into account recent experimental evidence for granular superconductivity in graphite. [ABSTRACT FROM AUTHOR]

We show that the voltage drop of specially prepared normal-superconducting-normal nanostructures show Andreev oscillations as a function of magnetic field or input current. These oscillations are due to the interference of the electron wave function between the normal parts of the structure that act as reflective interfaces, i.e. our devices behave as a Fabry–Perot interferometer for conduction electrons. The observed oscillations and field periods are well explained by theory. [ABSTRACT FROM AUTHOR]

The use of haptic (the sensing of touch) technology as an interactive tool for new diagnostic procedures is an important and interesting goal because of the potential benefits. We developed an algorithm for integration of haptic sensing in a medical 3D visualization environment. 3D reconstructions were generated from a stack of medical preoperative images. The innovation of the presented work is the improvement on the behavior of the haptic rendering over previous algorithms. First, the tool we developed for 3D reconstruction is presented. The classical pipeline for surface 3D reconstruction is reviewed from a parametric point of view. These parameters play an important role in the analysis of the haptic behavior. In addition, all the parameters of the reconstruction are accessible and can be modified on-line during the reconstruction procedure. Next, the software architecture used for the integration of the haptic devices is described. The haptic rendering algorithm is detailed, including the collision detection algorithm (a simple ray-tracing scheme programmed using VTK) that is used with the medical images. The results obtained by evaluation of the haptic algorithm’s behavior are presented, demonstrating acceptance of the interactive tool by medical professionals. An improved method for haptic sensing and interaction in a 3D medical visualization environment is feasible and promises to improve image-guided interventions and minimally invasive surgery. [ABSTRACT FROM AUTHOR]

To analyse the influence of cold ischemic time (CIT) (2–24 h) and of cryopreservation (liquid phase) on the viability of the valvular fibroblasts and in the presence of apoptosis. Cardiac valves from 10 pigs were evaluated by anatomo-pathological study of the wall, muscle and leaflet. At the same time, the presence of cellular death due to apoptosis was investigated in two ways; directly on tissue by Apodetec system and by two-colour flow cytometry assay analyzing a suspension of fibroblast from valve leaflets using Anexina V and propidium iodure (PI). We established three groups of samples to compare different experimental conditions: 2 h of ischemia (group 1), 24 h of ischemia (group 2), and a programme of cryopreservation (−1°C/min) after 2 h of ischemia, followed by storage in liquid nitrogen during a week and thawing was performed (group 3). The analysis of viabilities showed slight differences between all three groups. The results indicated CIT of 24 h undergoing more structural affectation than CIT of 2 h. Flow cytometry analysis did not show important differences between groups; however cryopreserved samples (group 3) slightly less viability and a higher percentage of death by apoptosis than group 1 and 2 using flow cytometry. Apoptosis was confirmed on tissue from all valves but mainly in samples of group 2 and group 3. In summary, the viability of the valves in the case of ischemic times of 2 h, 24 h or after cryopreservation/thawing differs slightly. The death of the cells is mainly mediated by necrosis and not by apoptosis. [ABSTRACT FROM AUTHOR]

Ceramic samples found in San Miguel Ixtapan, Mexico State, Mexico, were analyzed by means of NAA, PIXE, SEM and XRD. Statistical treatments such as bivariate cluster and principal-components analysis were applied to the data set. The origins of these ceramic samples were classified as local, regional and foreign. [ABSTRACT FROM AUTHOR]

Reconstitution of mitochondrial calcium transport activity requires the incorporation of membrane proteins into a lipidic ambient. Calcium uptake has been measured previously using Cytochrome oxidase vesicles. The enrichment of these vesicles with cardiolipin, an acidic phospholipid that is found only in the inner mitochondrial membrane of eukaryotic cells, strongly inhibits calcium transport, in remarkable contrast with the activation effect that cardiolipin exerts upon other mitochondrial transporters and enzymes. The relation of the inactivation of calcium transport to the physical state of the bilayer was studied by following the polarization changes of 1,6-diphenyl-1,3,5-hexatriene (DPH) and by flow cytometry in the cardiolipin-enriched liposomes with incorporated mitochondrial solubilized proteins. Non-bilayer molecular arrangements in the cardiolipin-supplemented liposomes, detected by flow cytometry, may produce the fluidity changes observed by fluorescence polarization of DPH. Fluidity changes correlate with the abolition of calcium uptake, but have no effect on the establishment of a membrane potential in the vesicles required for calcium transport activity. Changes in the membrane structure and uniporter function are observed in the combined presence of cardiolipin and calcium leading to a modified lipid configuration. [ABSTRACT FROM AUTHOR]

The performance of a dual plasma reactor in nitriding a H13 steel was investigated and compared to other nitriding methods applied to this material. The aim was to explore the advantages of combining a weakly ionized plasma unit and a postdischarge plasma reactor to process this material. Samples of H13 were nitrided at 500, 550, and 600 °C for times ranging between 5 to 10 h. The hardness distributions obtained revealed a substantial advantage of the present method over conventional gas nitriding and some improvement over other plasma-assisted methods, especially in the development of smooth profiles. This was attributed mainly to enhanced diffusion provided by the postdischarge flow. The evolution of hardness as a function of time and temperature displayed an aging type of behavior that was related to the formation and growth of CrN as the hardening phase. [ABSTRACT FROM AUTHOR]

We discuss an hypothesis wherein single-bubble sonoluminescence is attributed to electrical breakdown due to large pressure gradients existing for small bubble radii. These large gradients produce large electric fields (the flexoelectric effect) that lead to electrical breakdown, releasing energies up to 10-10 J, which is much larger than the light energy released in each cycle. This hypothesis appears to be consistent with several observations made in studies of the sonoluminescence process. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The kinetics of the eosin-sensitized photooxidation ([O(Δ)]-mediated) of the protein lysozyme (Lyso) was investigated under two different pH conditions (pH 7 and pH 11). Rates of oxygen consumption and the fade in the protein fluorescence spectrum upon sensitized irradiation were monitored. Parallel studies on both denatured Lyso (absence of the four-S-S- bridges in the protein) and different mixtures of the photooxidizable amino acids of Lyso were also carried out. The mixtures maintained the same molar ratio as in the native protein, and were selected just in order to throw into relief the preferential amino acids that were being photooxidized at both pH values. Under work conditions Lyso was only photooxidizable at pH 7, whereas the opposite accounted for the denatured protein: only measurable oxygen consumption was detected at pH 11. Nevertheless, Lyso at pH 11, evidenced an important physical quenching of O(Δ) due to the Tyr and Trp residues. The results for the native protein were interpreted on the basis of a previously described dark complex Eosin-Lyso, which selectively favours the photooxidation of the bounded protein. The Trp residues were the main reactive entities in the native protein. The photodinamic effect in denatured Lyso was characterized by the prevalence of Tyr residues as photooxidizable targets. In the discussion of the results, a comparisson with the photooxidation kinetics of the mixtures of free amino acids was made. [ABSTRACT FROM AUTHOR]

The effect of the substitution pattern on the kinetics of the Type II (O(Δ)-mediated) dye-sensitized photooxidation of a series of nine tyrosine derivatives was investigated. Overall (k) and reactive (k) rate constants for the interaction of the excited oxygen species with the amino acid derivatives were determined. A parallel study on solvent and pH effects was carried out. The presence of different substituents in nuclear positions or in the amino acid side chain greatly affect the photooxidation rates. An upper limit for photooxidation quantum yield, calculated from the kinetic data, varies from 0.03 to 0.25, being the higher for halogenated tyrosines and the lower for esterified tyrosines and for the nitro-derivative. The variation of solvent polarity and pH of the reaction medium confirm that the presence of the ionized phenolate group in tyrosine, clearly dominates the quenching process. As already postulated for generic phenolic derivatives, it proceeds through a polar intermediate complex which posses some component of charge-transfer character. Esterification of the carboxilic acid of tyrosine selectively decreases the contribution of the reactive step to the overall process of O(Δ) quenching. An amide group in the same position does not produce noticiable changes in this sense. The presence of a highly deactivating nitro group in nuclear positions greatly diminishes the magnitude of both overall and reactive interactions. For all three, o-, m- and p-tyrosine the values of photooxidation quantum yields show an excellent parallelism with the rates of consumption of the - NH group of the amino acid chain, upon sensitized irradiation. It could react, in the cases of 0- and m-tyrosine in a secondary, non photochemical, step. [ABSTRACT FROM AUTHOR]

The type II singlet molecular oxygen [O(Δ)]-mediated photo-oxidation of the tripeptide gly-tyr-ala was studied. It has two non-oxidizable amino-acids (gly and ala) bonded to the oxidizable one, tyr. Overall ( k) and reactive ( k) rate constants for the interaction were determined by time-resolved methods ( IR emission of O(Δ)) and stationary photolysis, in water at pH 11.5 as well as in alkaline non-aqueous etOH-MeCN (80:20, v/v, 10 mM in KOH) solutions. An important solvent polarity effect on k was detected; the rate constant increasing one order of magnitude in going from the organic mixture to water ( k HO = 2 × 10 M s). Nevertheless, k does not parallel this trend; gly-tyr-ala being less photooxidizable in a more polar environment. The effective quantum yield (∅) for TPE photooxidation is much higher in etOH-MeCN (∅ = 0.056) than in water (∅ = 0.023). Results are discussed on the basis of the formation of an exciplex with polar character between the TPE and O(Δ). Two remarkable points should be taken into account: a) the rate costants for the interaction of O(Δ) with gly-tyr-ala are practically the same as for free tyr. b) New -NH groups are generated upon sensitized irradiation. Both findings indicate that the peptide bonds in the TPE break as a result of the photooxidation. A thorough analysis with data for tyrosine and related dipeptides is undertaken. [ABSTRACT FROM AUTHOR]

Stroke in pregnancy and the puerperium is a rare but potentially devastating event. We present the case of a previously healthy woman who underwent a cesarean delivery and experienced a middle cerebral artery thrombosis in the immediate postpartum period that was subsequently lysed with intra-arterial urokinase. The patient made a complete neurologic recovery. To the best of our knowledge, this is the first reported case of successful intra-arterial thrombolysis for ischemic stroke in the postpartum period. [ABSTRACT FROM AUTHOR]

Objective: We sought to compare a 2-day quadruple therapy with a 14-day triple therapy in the treatment of Helicobacter pylori infection. Methods: Eighty-one consecutive patients with an endoscopically diagnosed peptic ulcer and demonstrated infection by H. pylori were included in the study. Patients were randomized to receive omeprazole 40 mg b.i.d., amoxicillin 2.5 g once daily, metronidazole 500 mg t.i.d., and bismuth subcitrate 360 mg t.i.d., for 2 days, followed by omeprazole 20 mg once daily for 6 additional days (Group 1) or a 14-day course of omeprazole 20 mg b.i.d., amoxicillin 1 g t.i.d., and metronidazole 500 mg t.i.d. (Group 2). Eradication was evaluated by antral biopsy and rapid urease test at 2 months after therapy and by C13-urea breath test after a year. Results: Two patients were lost to follow-up at 2 months. Intention-to-treat analysis showed that H. pylori infection was cured in 29 of 42 patients (69%; 95% Ch 53-82%) in Group 1 versus 36 of 39 (92%; 95% CI: 78-98%) of patients in Group 2 (p = 0.009). Per-protocol analysis showed a cure rate of 71% (95% CI: 55-84%) (29/41 patients) and 95% (95% CI: 81-99%) (36/38 patients), respectively (p = 0.007). Fifty-five of 65 cured patients returned 1 year after treatment (26 in Group 1, 29 in Group 2). All but one in Group 2 remained cured. There were no significant differences in compliance (88% in Group 1 versus 92% in Group 2) or in the presence of side effects (27 %; 95 % CI: 15-43% versus 41%; 95% CI: 26-58%; ns). Conclusion: Two-day quadruple therapy is significantly less effective than 2-wk triple treatment. [ABSTRACT FROM AUTHOR]

CO2 supply at 4% (v/v) in air increased the biooxidation of a gold concentrate (41% enargite, 43% pyrite) with Thiobacillus ferrooxidans in a 2-l bioreactor at 4% (w/v) solids concentration, 35°C and pH 2.4. Extraction increased from 21 to 69% for Fe, 19 to 25% for As, and 16 to 19% for Cu. Suspended biomass increased from 2.6·107 to 1.2·108 cells/ml. It is concluded that the biooxidation of this gold concentrate is limited by the rate of CO2 supply. © Rapid Science Ltd. 1998 [ABSTRACT FROM AUTHOR]