Germination,Viability and Clearance of Stachybotrys chartarum in the Lungs of Infant Rats

Observing that the conidia of Stachybotrys chartarum can germinate in the lung of infant rats, it became important to ascertain whether an infection can ensue. Viable conidia of S. chartarum were instilled into the lungs of 4 and 14 day-old rat pups. Germination was observed frequently in the lungs of 4 day-old but rarely in the 14 day-old pups. In the 4 day-old pups, pulmonary inflammation with hemorrhagic exudates was observed and resulted in about 15% mortality rate compared to 0% for the controls instilled with phosphate buffered saline. Acute neutrophilic inflammation and intense interstitial pneumonia with poorly formed granulomas observed three days following exposure were associated with fungal hyphae and conidia. The surviving experimental pups showed significantly slower weight gain for seven days. Dilution plating and quantitative PCR analysis were used to follow total fungal load in the rat pups lung homogenates. In the 4 day-old rat pups viable fungi decreased rapidly and were less than 1% by day seven. Similarly, fungal DNA decreased exponentially and was only 0.03% by fourteen days after exposure. However, 14 day-old rat pups showed neither the lethal effects of exposures to viable conidia of S. chartarum nor the slower weight gain, and the fungal load decreased even more rapidly. We conclude that S. chartarum conidia can initially germinate and form hyphae but even in the immature rat pups do not establish an effective infection, although a very limited persistence cannot be excluded.This revised version was published online in October 2005 with corrections to the Cover Date.     

Production of antibacterial substances by bifidobacterial isolates from infant stool active against Listeria monocytogenes

AIMS: This study aimed to characterize new isolates of human bifidobacteria, evaluate some of their probiotic potential and to screen these isolates for their effectiveness at inhibiting Listeria monocytogenes in vitro. METHODS AND RESULTS: Thirty-four Bifidobacterium isolates from infant faeces were identified by fructose-6-phosphate phosphoketolase and PCR. Six isolates, coded RBL67, RBL68, RBL69, RBL70, RBL85 and RBL86, showed higher antagonistic activity against L. monocytogenes. Neutralized culture supernatants of these strains did not inhibit L. monocytogenes when tested by agar diffusion method. However, the concentration of supernatant by speed-vac resulted in the formation of an inhibitory effect with supernatants from strains RBL67, RBL68 and RBL70. This effect was shown to be related to heat-stable proteinaceous compound(s) which were resistant to heating at 100 degrees C for 5 min but not to pronase-E, proteinase-K or trypsin. The extraction of the inhibitory compounds by methanol-acetone extraction procedure indicated that four strains (RBL67, RBL68, RBL69 and RBL70) were mostly soluble in acetone. However, strain RBL85 produced inhibitory substances that were soluble in methanol. CONCLUSION: Infant bifidobacterial isolates produce heat-stable proteinaceous compounds active against L. monocytogenes. SIGNIFICANCE AND IMPACT OF THE STUDY: Production of antibacterial substances by bifidobacteria would improve intestinal bacterial ecology and inhibit intestinal pathogens.     

Infant mortality after takeovers in wild Ethiopian hamadryas baboons

In this work we report the first observational evidence of infanticide in wild hamadryas baboons. The study group inhabits the lowlands of the northern Rift Valley in Ethiopia and has been under observation for over 1,200 hr, on and off, since October 1996. Here we report observations from August and September 2002 of the consequences of two takeovers of known females with black infants. After the first takeover, the respective infant disappeared and was presumed dead within 11 days of the takeover. After the second takeover, the infant incurred repeated severe aggression from its mother's new leader male and eventually died 4 days after the takeover. We interpret these findings as support for the sexual selection hypothesis regarding male infanticide. We suggest that hamadryas leader males usually protect infants born into their units, but may withhold this protection-or even directly attack and kill infants-after takeovers.     

High abscission rates of damaged expanding leaves: field evidence from seedlings of a Bornean rain forest tree

Herbivore damage is known to cause the premature loss of mature leaves. However, the effects of herbivory on abscission during the early stages of leaf development remain unexplored, even though herbivores frequently prefer unlignified, immature leaves. In a field experiment, we removed 50% of the tissue from leaves at various stages of development on seedlings of Shorea hopeifolia (Dipterocarpaceae), a dominant rain forest tree in Indonesian Borneo. Four weeks following simulated herbivory, >88% of unlignified expanding leaves had been abscised, compared to only 20% of fully expanded, unlignified leaves and 0% of recently lignified, mature leaves. In a separate experiment over 9 wk, simulated herbivory did not increase abscission rates of mature leaves, even when 75% of leaf tissue was removed. Because most (58%) of S. hopeifolia seedlings under natural conditions had lost 1% or less of the tissue from their mature leaves, herbivore damage probably has little effect on the abscission of mature leaves. In contrast, the tendency for damaged expanding leaves to abscise may explain why 49% of S. hopeifolia seedlings had already lost their youngest leaf. If similar patterns occur in other species, herbivore attacks on developing leaves may contribute substantially to both leaf loss and the cumulative impact of herbivory on the growth and survival of whole plants.     

In vitro dialyzability of zinc from different salts used in the supplementation of infant formulas

Seven zinc salts—acetate, chloride, lactate, sulfate, citrate, gluconate, and oxide—were added to milk—and soy-based infant formulas to estimate possible differences in zinc availability depending on the type of salt used. For this purpose, an in vitro method that estimates the dialyzability of the element (i.e., the fraction available for absorption) was applied. Zinc dialyzability is always higher in milk-based products than in soy products, even when the total zinc contents are higher in the latter. The salts can be classified according to the zinc dialyzability in the two types of formulas as follows: oxide>gluconate=chloride=lactate>citrate=acetate>sulfate. Therefore, according to the dialysis percentage, oxide and gluconate are the compounds of choice for zinc supplementation of infant formulas.     

Are life cycle assessments a threat to sound public policy making?

This paper deals with the question of whether Life Cycle Assessments (LCAs), with their focus on objective and quantitative results, are the best way to support public policy processes. The public policy making process is characterized as a continuous discoursive struggle. Criteria are defined to distinguish between good and bad public policy discourses to judge the effects of LCA on the public policy process. Many policy scientists argue that methodologies that emphasize quantification and the use of formal methods are not beneficial for sound public policy making. An empirical report of the role LCAs played in public policy making processes on PVC and chlorine in the Netherlands is made to evaluate the contribution of LCAs to public policy making processes and to identify the main limitations of the current LCA methodologies and practices. It appears that political actors tend to use LCAs in a polarizing way. LCAs are easily misused due to their apparent objectivity, and the quantitative and black box nature of their results. LCAs contain an implicit, normative frame that does not match the environmentalists’ perception on the kind of evidence needed on toxic effects of organochlorines, which reduced the open nature of the Dutch PVC debate. It is recommended to develop a methodology for product evaluation that approaches the issue in a more open and emergent way to prevent “premature closure” of the analysis. It is expected that a focus on the development of balanced, rich arguments on facts and values in the study process will be more fruitful than the calculation of integral, quantitative indicators.     

Influences of milk components on biofilm formation of Cronobacter spp. (Enterobacter sakazakii)

Aim:  To determine the critical component(s) of skim milk for biofilm formation of Cronobacter species.
Methods and Results:  Biofilm forming ability of 72 Cronobacter strains in skim milk preparation was assayed by crystal violet staining. The results revealed that whey protein and casein are more important determinants of skim milk for biofilm formation than lactose, although there was a wide variation in biofilm forming ability. Biofilm structure and capsular material of six strains exhibiting different biofilm forming ability was investigated via electron microscopes. Scanning electron microscopy showed visually that while the strong biofilm formers (E27B, FSM 30 and 2·82) resulted in almost complete coagulation of skim milk, the weak biofilm formers (55, FSM 290 and 2·84) caused less coagulation. No capsule was clearly delineated in transmission electron micrographs of either strong or weak biofilm formers.
Conclusion:  These results indicate that, for biofilm formation of Cronobacter species in skim milk, nitrogen source is probably a more important determinant than carbohydrate, and that strong biofilm formers are responsible for substantial coagulation of skim milk.
Significance and Impact of the Study:  This study provides information for better understanding of the underlying mechanisms by which Cronobacter species form biofilm in infant formula milk.     

Development of the infant intestinal microbiome: A bird's eye view of a complex process

Infants undergo profound shifts in colonizing intestinal microorganisms during their first year, especially during and after birth and during weaning. Microbiota are passed to infants through the placenta, during the vaginal birth process, and from early diet and other environmental exposures. These microbiota play an active role in the development of healthy infant metabolic and immunologic systems; profound shifts in microbiotal populations can be persistent, are associated with immediate alterations in gene expression, metabolic, immunologic, and neurologic function, and with downstream metabolic and immunologic consequences such as obesity, allergies, asthma, autoimmune diseases, and potentially neurologic conditions. Many modern exposures, including Cesarean section, formula feeding, and antibiotics, have been associated with microbiome shifts, and also with downstream diseases; while many published studies considered exposures individually, a more comprehensive understanding of their interaction and impact will consider the entirety of the infant's environment. It is not possible, nor desirable, to return to a world without toilets, sewers, tap water, delivery room antisepsis, Cesarean sections, antibiotics, immunizations, and refrigerators; our other alternative is to better understand these complex changes in infant developmental and molecular physiology. Protecting and repairing the developmental processes of the healthy infant microbiome is the modern medical frontier. Birth Defects Research (Part C) 105:228–239, 2015. © 2015 Wiley Periodicals, Inc.     

西藏小昌都黑白仰鼻猴的雄婴照料:能量胁迫导致?

雄猴照料婴猴行为通常都是从雄猴的角度来分析该行为具有何种适应功能,很少有研究关心为什么雌猴会让雄猴参与照料活动。该文通过西藏小昌都黑白仰鼻猴群的系统观察取样,采用回归分析雄婴照料行为季节变动与婴猴年龄及生态因子（环境温度、食物供应）之间的关系,试图分析是否由于能量胁迫导致雌猴让雄猴参与照料活动,并通过分析高能量胁迫季节（环境温度低、食物缺乏,婴猴年幼需要雌猴携带多）与低能量胁迫季节（环境温度高、食物丰富,婴猴年长需要雌猴携带少）雄婴照料行为差异检验了能量胁迫假说。结果表明雄婴照料行为与温度呈负相关函数,而雌猴照料婴猴行为与温度呈正相关函数;在高能量胁迫的季节,雄猴参与照料行为多,而在低能量胁迫的季节雄猴照料行为少。因此,作者认为是能量胁迫迫使雌猴放弃部分照料婴猴的机会,雄猴利用照料机会获得了其他利益。