Effects of gamma radiation on raspberries: safety and quality issues.

There is an ever-increasing global demand from consumers for high-quality foods with major emphasis placed on quality and safety attributes. One of the main demands that consumers display is for minimally processed, high-nutrition/low-energy natural foods with no or minimal chemical preservatives. The nutritional value of raspberry fruit is widely recognized. In particular, red raspberries are known to demonstrate a strong antioxidant capacity that might prove beneficial to human health by preventing free radical-induced oxidative stress. However, food products that are consumed raw, are increasingly being recognized as important vehicles for transmission of human pathogens. Food irradiation is one of the few technologies that address both food quality and safety by virtue of its ability to control spoilage and foodborne pathogenic microorganisms without significantly affecting sensory or other organoleptic attributes of the food. Food irradiation is well established as a physical, nonthermal treatment (cold pasteurization) that processes foods at or nearly at ambient temperature in the final packaging, reducing the possibility of cross contamination until the food is actually used by the consumer. The aim of this study was to evaluate effects of gamma radiation on raspberries in order to assess consequences of irradiation. Freshly packed raspberries (Rubus idaeus L.) were irradiated in a (60)Co source at several doses (0.5, 1, or 1.5 kGy). Bioburden, total phenolic content, antioxidant activity, physicochemical properties such as texture, color, pH, soluble solids content, and acidity, and sensorial parameters were assessed before and after irradiation and during storage time up to 14 d at 4°C. Characterization of raspberries microbiota showed an average bioburden value of 10(4) colony-forming units (CFU)/g and a diverse microbial population predominantly composed of two morphological types (gram-negative, oxidase-negative rods, 35%, and filamentous fungi, 41%). The inactivation studies on the raspberries mesophilic population indicated a one log reduction of microbial load (95% inactivation efficiency for 1.5 kGy), in the surviving population mainly constituted by filamentous fungi (79-98%). The total phenolic content of raspberries indicated an increase with radiation doses and a decrease with storage time. The same trend was found for raspberries' antioxidant capacity with storage time. Regarding raspberries physicochemical properties, irradiation induced a significant decrease in firmness compared with nonirradiated fruit. However, nonirradiated and irradiated fruit presented similar physicochemical and sensory properties during storage time. Further studies are needed to elucidate the benefits of irradiation as a raspberries treatment process.

Physiological and physico-chemical characterization of dietary fibre from the green seaweed Ulva fasciata Delile / Caracterização fisiológica e físico-química da fibra alimentar da macroalga marinha verde Ulva fasciata Delile

This work aims to assess the potential of the green seaweed Ulva fasciata Delile as an alternative source of dietary fibre (DF). Total DF content was determined, some of its physico-chemical properties described and the physiological effects of U. fasciata meal on rats fed a hypercholesterolemic diet were investigated. U. fasciata may be considered a potential alternative source of DF with a total content of about 400 g.kg-1 (dry basis) and interesting physico-chemical properties: water retention capacity of 8.74 g/water.g-1 dry sample (seaweed meal) and 0.90 (seaweed carbohydrate extract), lipid adsorption capacity of 4.52 g/oil.g-1 dry sample (seaweed meal) and 5.70 (seaweed carbohydrate extract), intrinsic viscosity of 2.4 dl.g-1 (seaweed carbohydrate extract) and cation exchange capacity of 3.51 Eq.kg-1 (seaweed carbohydrate extract). The diet containing seaweed meal was able to keep rats' total cholesterol (TC) down without causing any undesirable increase in LDL-C fraction. No evidence of toxic and/or antinutritional components in the seaweed meal was detected. Rats showed a fecal volume much greater (13 g) than that fed on cellulose diet ( 7 g) (p < 0.05). These properties confer on the seaweed the potential to be used in food technology for the acquisition of low-calorie food and might be important in body weight control, reduction of blood TC and LDL-C as well as in prevention of gastrointestinal diseases.

Este trabalho objetivou avaliar o potencial da alga marinha verde Ulva fasciata Delile como fonte alternativa de fibra alimentar. Foram realizadas a determinação do teor de fibra alimentar total e a descrição de algumas propriedades físico-químicas, e os efeitos fisiológicos da farinha da alga seca sobre ratos alimentados com dieta hipercolesterolemizante foram investigados. Esta alga pode ser considerada uma fonte alternativa potencial de fibra com cerca de 400 g.kg-1 (base seca) e propriedades físico-químicas interessantes: uma capacidade de retenção de água de 8,74 g/água.g-1 de amostra seca (farinha de alga) e 0,90 (extrato de carboidratos), uma capacidade de adsorção de lipídeos de 4,52 g/óleo.g-1 de amostra seca (farinha de alga) e 5,70 (extrato de carboidratos), uma viscosidade intrínseca de 2,4 dl.g-1 (extrato de carboidrato da alga) e capacidade de troca iônica de 3,51 Eq.kg-1 (extrato de carboidrato). A dieta contendo farinha de alga foi capaz de manter baixos os níveis de colesterol total de ratos sem causar aumento indesejável na fração LDL-C. Nenhuma evidência de componentes tóxicos e/ou antinutricionais na farinha de alga foi encontrada. Os ratos mostraram um volume fecal maior (13 g) do que aqueles alimentados com dieta contendo celulose como fonte de fibra (7 g) (p < 0,05). Essas propriedades conferem a alga o potencial de ser utilizada na tecnologia de alimentos para a aquisição de alimentos de baixas calorias, podendo ser importante para o controle do peso corporal, redução do colesterol sanguíneo total e da fração LDL-C, como também na prevenção de doenças gastrintestinais.

Contested dominance modifies the anovulatory consequences of social subordination in female marmosets.

Dominance status among female marmosets is reflected in agonistic behavior and ovarian function. Socially dominant females receive submissive behavior from subordinates, while exhibiting normal ovulatory function. Subordinate females, however, receive agonistic behavior from dominants, while exhibiting reduced or absent ovulatory function. Such disparity in female fertility is not absolute, and groups with two breeding females have been described. The data reported here were obtained from 8 female-female pairs of captive female marmosets, each housed with a single unrelated male. Pairs were classified into two groups: "uncontested" dominance (UD) and "contested" dominance (CD), with 4 pairs each. Dominant females in UD pairs showed significantly higher frequencies (4.1) of agonism (piloerection, attack and chasing) than their subordinates (0.36), and agonistic behaviors were overall more frequently displayed by CD than by UD pairs. Subordinates in CD pairs exhibited more agonistic behavior (2.9) than subordinates in UD pairs (0.36), which displayed significantly more submissive (6.97) behaviors than their dominants (0.35). The data suggest that there is more than one kind of dominance relationship between female common marmosets. Assessment of progesterone levels showed that while subordinates in UD pairs appeared to be anovulatory, the degree of ovulatory disruption in subordinates of CD pairs was more varied and less complete. We suggest that such variation in female-female social dominance relationships and the associated variation in the degree and reliability of fertility suppression may explain variations of the reproductive condition of free-living groups of common marmosets.

Contested dominance modifies the anovulatory consequences of social subordination in female marmosets

Dominance status among female marmosets is reflected in agonistic behavior and ovarian function. Socially dominant females receive submissive behavior from subordinates, while exhibiting normal ovulatory function. Subordinate females, however, receive agonistic behavior from dominants, while exhibiting reduced or absent ovulatory function. Such disparity in female fertility is not absolute, and groups with two breeding females have been described. The data reported here were obtained from 8 female-female pairs of captive female marmosets, each housed with a single unrelated male. Pairs were classified into two groups: "uncontested" dominance (UD) and "contested" dominance (CD), with 4 pairs each. Dominant females in UD pairs showed significantly higher frequencies (4.1) of agonism (piloerection, attack and chasing) than their subordinates (0.36), and agonistic behaviors were overall more frequently displayed by CD than by UD pairs. Subordinates in CD pairs exhibited more agonistic behavior (2.9) than subordinates in UD pairs (0.36), which displayed significantly more submissive (6.97) behaviors than their dominants (0.35). The data suggest that there is more than one kind of dominance relationship between female common marmosets. Assessment of progesterone levels showed that while subordinates in UD pairs appeared to be anovulatory, the degree of ovulatory disruption in subordinates of CD pairs was more varied and less complete. We suggest that such variation in female-female social dominance relationships and the associated variation in the degree and reliability of fertility suppression may explain variations of the reproductive condition of free-living groups of common marmosets.

Fecal androgen levels in common marmoset (Callithrix jacchus) males living in captive family groups

In captive common marmoset groups, the reproductive inhibition observed in subordinate female seems to be a result of olfactory, visual and behavioral cues from the dominant female. However, few studies have examined the relationship among adult males living in the same social group. These studies have shown that reproductive failure among peer males seems to be based on hormonal and behavioral mechanisms. New insights on sexual strategies in primates have been shown using fecal steroids, but so far no information is available for common marmoset males. In the present study, we evaluated the influence of light-dark cycle, age and reproductive condition on the profile of fecal androgens in males living in the same family group. Feces were collected from six fathers and six sons for androgen determination during the light phase of the 24-h cycle for eight days randomly distributed over a 4-week period. Androgen levels were determined by enzyme immunoassay technique. Adult sons showed higher androgen levels (166.97 ± 22.95 ng/g) than fathers (80.69 ± 44.38 ng/g) and juveniles (49.06 ± 23.15 ng/g; P < 0.05). No diurnal variation (P > 0.05) in fecal androgen profile was observed in adults or juveniles. No indication of androgen-mediated social competition between fathers and adult sons was demonstrable. These results provide basic information on fecal androgen profile useful to investigate the socioendocrinology of free-ranging common marmoset males and verify that, in contrast to daughters, the reproductive suppression of sons is not based on physiological inhibition of their gonads.

Percepção da dor isquêmica e a pressão em mulheres jovens durante o ciclo menstrual: associação entre estados de humor e níveis de cortisol / Perception of ischemic and pressing pain in young women during menstrual cycle. Association with humor and cortisol levels

PURPOSE: The aim of the present study was to investigate the modulation of pain perception, estimate by both threshold and tolerance to ischemic and pressure stimuli, by cortisol and humor states across the menstrual cycle. METHODS: Threshold and tolerance pain to ischemic and pressure stimuli were determined in eighteen healthy young women. The menstrual cycle phases were determined using oral temperature, documentation of the first and last day of menstruation and plasma levels of progesterone and estradiol. Statistical analysis using linear regression model (R2) indicate which hormonal variables (estradiol, progesterone and cortisol) and/or variables obtained from the questionnaire Profile of Mood States (POMS) (fatigue, tension, anger, vigor, confusion and depression) explain, isolated or together, each one of the pain parameters during the five phases of the menstrual cycle. RESULTS: In the follicular, periovulatory, early-to-middle luteal and menstrual phases hormones and subjective variables from POMS explained the responses for pain threshold and tolerance to ischemic and pressure stimulus. Estradiol (during follicular, peri-ovulatory and menstrual phases) and cortisol (during follicular, early-to-mid luteal and mestrual phases) explain only the pain perception to pressure. The differential participation of the hormones in the two types of pain suggests that estradiol, and probably cortisol, modulate the pathways related to pressure but not those related to ischemic pain. On the other hand only the mood states variables explained pain perception during late luteal phase. CONCLUSIONS: The analysis of hormonal and subjective variables (POMS) together, associated to detailed characterization of the menstrual cycle suggest that participation of estradiol and cortisol modulate pain perception to pressure stimulus but not to ischemic one. Indeed, suggest that in healthy women with regular menstrual cycles, only subjective variables explained pain perception during late luteal phase of menstrual cycle.

[Prevalence of Helicobacter pylori infection in children evaluated at "Hospital de Clínicas de Porto Alegre", RS, Brazil]. / Prevalência de infecção por, Helicobacter pylori em crianças avaliadas no Hospital de Clínicas de Porto Alegre, RS, Brasil.

OBJECTIVES: To determine prevalence of Helicobacter pylori infection in a group of symptomatic patients between 2 and 18 years old who were submitted to gastric biopsy during upper endoscopy done in the period of 1990-97. To correlate the histological findings with clinical and endoscopical data. METHODS: A cross-sectional study done after review of clinical and histopathological data. Histopathological sections were reviewed by a pathologist, who did not know the clinical information and the previous histopathological reports. RESULTS: Among 181 patients evaluated, prevalence of Helicobacter pylori infection was 24.86% (45 positive cases). In pathological analysis, gastritis was found in 38/45 of the positive Helicobacter pylori patients and in 45/136 negative Helicobacter pylori. Gastric ulceration was found in 6/45 positive Helicobacter pylori and in 3/136 negative Helicobacter pylori. CONCLUSION: This study stated a significative association between Helicobacter pylori infection and pathological abnormalities in children evaluated in the "Hospital de Clínicas de Porto Alegre", RS, Brazil.

Behavior and progesterone levels in Callithrix jacchus females.

In callitrichids, and especially in the Callithrix and Saguinus genera, reproductive suppression maintains the breeding exclusivity of dominant females. It has been suggested that dominance may be inferred from agonistic behavior of females. The purpose of this study was to assess the adequacy of behaviors as indicators of hormonal status in Callithrix jacchus females. Two pairs of twin females were observed for affiliative, agonistic and sexual behaviors for 20 weeks, in four stages of increasingly potential competition for one male. During the same period, blood samples were taken regularly for progesterone determination by ELISA. The two pairs differed markedly as to behaviors and hormonal status: pair 1 showed a well established behavioral dominance and only one ovulating female from the beginning of the observation period; pair 2 showed competition for dominance until the last stage of observation, when one of the females started ovulating. Correlations between behaviors and progesterone levels showed differences between subordinate and dominant females mostly in pair 2. Although limited in number of animals studied, these results suggest that there is a relationship between behavior and hormones in female marmosets, but this relationship may be useful in the identification of the physiological status of females only in groups where the dominance is not well established.

Behavior and progesterone levels in Callithrix jacchus females

In callitrichids, and especially in the Callithrix and Saguinus genera, reproductive suppression maintains the breeding exclusivity of dominant females. It has been suggested that dominance may be inferred from agonistic behavior of females. The purpose of this study was to assess the adequacy of behaviors as indicators of hormonal status in Callithrix jacchus females. Two paires of twin females were observed for affiliative, agonistic and sexual behaviors for 20 weeks, in four stages of increasingly potential competition for one male. During the same period, blood samples were taken regularly for progesterone determination by ELISA. The two pairs differed markedly as to behaviors and hormonal status: pair 1 showed a well established behavioral dominance and only one ovulating female from the beginning of the observation period; pair 2 showed competition for dominance until the last stage of observation, when one of the females started ovulating. Correlations between behaviors and progesterone levels showed differences between subordinate and dominant females mostly in pair 2. Although limited in number of animals studied, these results suggest that there is a relationship between behavior and hormones in female marmosets, but this relationship may be useful in the identification of the physiological status of females only in groups where the dominance is not well estblished

The effect of parturition on the interactions within pairs of common marmosets (Callithrix jacchus)

The relationship within common marmoset (Callithrix jacchus) pairs is based on pair-bond formation. This pair-bond is important for the successful rearing of the young and for the enhancement of reproductive success. Female marmosets bear twins which are carried mainly by males starting on the first day after the birth of the infants. Little is known, however, about the patterns of sociosexual interaction between callitrichid pairs and how these interactions change after the arrival of offspring. To evaluate the effect of parturition on these interactions, three heterosexual pairs of common marmosets were observed for four weeks before and four weeks after the birth of infants. The animals were kept in individual outdoor cages of the Nucleo de Primatologia, under environmental conditions. The time spent in proximity was mainly attributable to the initiative of females before parturition and the iniatiative of males after the offspring arrived. Males were groomed more before than after the birth of infants. In contrast, the amount of grooming received by females was the same in the two situations. These observations suggest that the relationship within pairs of common marmosets is slightly modified by the birth of infants and indicates that males and females could be using different strategies to enhance their reproductive success