An Outlook on Implantable Biosensors for Personalized Medicine

Biosensors are a fast-growing field,as they have been shown to be very helpful in our daily life,playing roles in industries such as agriculture,food safety,hom...     

An ultrastructural study of spermiogenesis in two species of Sitophilus (Coleoptera: Curculionidae).

The spermiogenesis of Sitophilus zeamais and Sitophilus oryzae, the maize and the rice weevil, respectively, was studied by light microscopy and scanning and transmission electron microscopy. Sitophilus spp. is the most widespread and destructive primary pest of stored cereals in the world. The spermiogenesis occurs within cysts. There are approximately 256 germ line cells per cyst. Inside each cysts, all the spermatids are in the same stage of maturation. The ultrastructure of the spermatozoa of S. zeamais and S. oryzae is similar to that described for other beetles. The head is formed by a three-layered acrosome with the perforatorium, the acrosomal vesicle, the extra-acrosomal layer and the nucleus. The flagellum has the typical axoneme formed by a 9+9+2 microtubules arrangement, two mitochondrial derivatives and two accessory bodies. The typical pattern for Curculionidae spermatozoa described here may provide useful information for future phylogenetic analysis of the superfamily Curculionoidea.     

Involvement of residues 296-299 in the enzymatic activity of tissue-type plasminogen activator

The tetra-alanine substitution variant KHRR 296–299 AAAAof tissue-type plasminogen activator (t-PA) was previously shownto have enhanced fibrin specificity and enhanced activity inthe presence of fibrin compared with the wild-type form of themolecule. The structural requirements for these alterationsin enzymatic activity were investigated by constructing severalamino acid substitution variants at each of the positions from296 to 299 and evaluating their activities under a variety ofconditions. Effects on plasminogen activator activity were commonamong the point mutants at positions 296–299; nearly allhad a phenotype similar to the KHRR 296–299 AAAA variant.The greatest effects on enzymatic function were found with multiplesubstitution variants, but some single charge reversals andproline substitutions had substantial effects. The enhancedfibrin specificity of KHRR 296–299 AAAA t-PA results inless fibrinogenolysis than seen with wild-type t-PA. Approximatelyfour times greater concentration of KHRR 296–299 AAAAcompared with wild-type t-PA was required to consume 50% ofthe fibrinogen in human plasma.     

Discoloration process modeling by neural network

The photo-oxidation of acid orange 52 dye was performed in the presence of H₂O₂, utilizing UV light, aiming the discoloration process modeling and the process variable influence characterization. The discoloration process was modeled by the use of feedforward neural network. Each sample was characterized by five independent variables (dye concentration, pH, hydrogen peroxide volume, temperature and time of operation) and a dependent variable (absorbance). The neural model has also provided, through Garson Partition coefficients and the Pertubation method, the independent variable influence order determination. The results indicated that the time of operation was the predominant variable and reaction mean temperature was the lesser influent variable. The neural model obtained presented coefficients of correlation on the order 0.98, for sets of trainability, validation and testing, indicating the power of prediction of the model and its character of generalization.     

Some views of 10th-grade students on marriage and family and there from deducible crucial points for sex education]

On the basis of two cases of sub-adventitial traumatic rupture of the left renal artery, as well as data from the literature, the authors indicate the relative poverty of clinical signs of traumatic rupture of the renal arteries. They stress the value of early intravenous pyelography in lumbar trauma, with immediate arteriography in the presence of a non-functioning kidney, making conservative surgery possible.     

Zinc bioavailability in different beans as affected by cultivar type and cooking conditions

Zinc bioavailability was studied in five cultivars of beans (Phaseolus vulgaris, L): white (Ouro Branco), black (Diamante Negro), and brown (BRS Radiante, Pérola and Talismã) cooked with or without soaking water. The cooked bean flours or ZnCO₃ were added to the test or control diets to provide 15 mg Zn/kg diet and were fed to weaning Wistar male rats for 42 days. Blood and femur were collected for analyses of plasma and erythrocyte Zn, bone weight and bone/dietary mineral ratio. Zinc bioavailability of Ouro Branco bean cooked with soaking water was higher than the other cultivars and similar to the control diet. Talismã without soaking water showed the lowest values for most of the parameters analyzed. Zinc bioavailability was not affected neither by the cooking process itself nor by the contents of phytate, tannins and dietary fiber, but it varied according to the bean cultivar and the phytate × calcium:zinc molar ratio.     

Analytical Methods Applied to the Chemical Characterization and Antioxidant Properties of Three Wild Edible Mushroom Species from Northeastern Portugal

The chemical composition and the antioxidant potential of three species of wild mushrooms from Northeastern Portugal, namely Agaricus albertii, Agaricus urinascens var. excellens, and Pleurotus eryngii, were compared. Standard procedures were followed in the nutritional value evaluation, while chromatographic procedures were used to analyze free sugars, fatty acids, tocopherols, phenolic compounds, and organic acids. To assess the antioxidant potential, reducing power, radical-scavenging activity, and lipid peroxidation inhibition were evaluated. P. eryngii revealed the highest levels of macronutrients, except proteins, as also the highest sugars, tocopherols, and monounsaturated fatty acids contents. A. albertii and A. urinascens var. excellens showed similar macronutrients composition. However, A. albertii revealed the highest content in PUFA and phenolic compounds. P. eryngii revealed the highest reducing power and radical-scavenging activity and A. albertii the highest lipid peroxidation inhibition. This study provides a detailed chemical characterization and antioxidant potential evaluation of three species of wild mushrooms from Portugal not yet previously reported. Thus, this work intended to contribute to the increase of information concerning species of edible mushrooms (directed to the scientific community and general population) as well as contribute to the conservation of these resources as sources of compounds of interest.     

Evaluation of somatic cell count thresholds to detect subclinical mastitis in Gyr cows

The objectives of this study were (1) to determine the sensitivity (Se) and specificity (Sp) of somatic cell count (SCC) thresholds to identify subclinical mastitis in Gyr cows caused by major and minor pathogens; (2) to study the effects of month of sampling, rear or front mammary quarters, herd, intramammary infection (IMI), and bacterial species on SCC at quarter level; and (3) to describe the prevalence of IMI in Gyr cows in commercial dairy herds. In total, 221 lactating Gyr cows from 3 commercial dairy farms were selected. Milk samples were collected from individual quarters once a month for 1 yr from all lactating cows for SCC and bacteriological analysis. Mammary quarters were considered the experimental units and the SCC results were log₁₀-transformed. Four SCC thresholds (100, 200, 300 and 400 × 10³ cells/mL) were used to determine Se and Sp to identify infected mammary quarters. The overall prevalence of IMI in quarter milk samples of Gyr cows was 49.8%, and the prevalence of minor pathogens was higher (31.9%) than that of major pathogens (17.8%). Quarter samples with microbial isolation presented higher SCC compared with negative samples. Sensitivity and Sp of selected SCC thresholds varied according to the group of pathogen (major and minor) involved in the IMI definition. Sensitivity increased and Sp decreased when mammary quarters with only major pathogens isolation were considered positive. The use of a single SCC analysis to classify quarters as uninfected or infected in Gyr cows may not be a useful test for this breed because Se and Sp of SCC at the studied thresholds were low. The occurrence of IMI and the bacterial species are the main factors responsible for SCC variation in mammary quarters of Gyr cows. Milk samples with major pathogens isolation elicited higher SCC than those with minor pathogens.