Co-cropping with three phytoremediation crops influences rhizosphere microbiome community in contaminated soil.

Human industrial activities have left millions of hectares of land polluted with trace element metals and persistent organic pollutants (POPs) around the world. Although contaminated sites are environmentally damaging, high economic costs often discourage soil remediation efforts. Phytoremediation is a potential green technology solution but can be challenging due to the diversity of anthropogenic contaminants. Co-cropping could provide improved tolerance to diverse soil challenges by taking advantage of distinct crop capabilities. Co-cropping of three species with potentially complementary functions, Festuca arundinacea, Salix miyabeana and Medicago sativa, perform well on diversely contaminated soils. Here, rhizosphere microbiomes of each crop in monoculture and in all co-cropping combinations were compared using 16S rRNA gene amplification, sequencing and differential abundance analysis. The hyperaccumulating F. arundinacea rhizosphere microbiome included putative plant growth promoting bacteria (PGPB) and metal tolerance species, such as Rhizorhapis suberifaciens, Cellvibrio fibrivorans and Pseudomonas lini. The rhizosphere microbiome of the fast-growing tree S. miyabeana included diverse taxa involved in POP degradation, including the species Phenylobacterium panacis. The well-characterised nitrogen-fixing M. sativa microbiome species, Sinorhizobium meliloti, was identified alongside others involved in nutrient acquisition and putative yet-to-be-cultured Candidatus saccharibacteria (TM7-1 group). The majority of differentially abundant rhizosphere-associated bacterial species were maintained in co-cropping pairs, with pairs having higher numbers of differentially abundant taxa than monocultures in all cases. This was not the case when all three crops were co-cropped, where most host-specific bacterial species were not detected as differentially abundant, indicating the potential for reduced rhizosphere functionality. The crops cultivated in pairs here retained rhizosphere microbiome bacteria involved in these monoculture ecosystem services of plant growth promotion, POP tolerance and degradation, and improved nutrient acquisition. These findings provide a promising outlook of the potential for complementary co-cropping strategies for phytoremediation of the multifaceted anthropogenic pollution which can disastrously affect soils around the world.

Differential uptake of silver, copper and zinc suggests complementary species-specific phytoextraction potential.

The aim of our study, conducted as a pot experiment, was to assess the potential of willow (Salix miyabeana), alfalfa (Medicago sativa), tall fescue (Festuca arundinacea), and Indian mustard (Brassica juncea) to remediate two brownfield soils differentially contaminated with Ag, Cu and Zn (up to 113.60, 47.50, and 117.00 mg kg(-1) respectively). While aboveground Ag accumulation was highest in B. juncea (4.60 ± 2.58 mg kg(-1)), lower levels were also measured in M. sativa and F. arundinacea. Cu accumulation was observed in all species, but only in underground parts, and was highest in F. arundinacea (269.20 ± 74.75 mg kg(-1)), with a bioconcentration factor of 13.85. Salix miyabeana was found to have the highest Zn aerial tissue concentration (119.96 ± 20.04 mg kg(-1)). Because of its high Ag uptake, the remediation potential of B. juncea should be evaluated more extensively on the site from which we excavated the soil for this study. Given the multiple forms of contamination on the site and the differential specie-related uptake evident in our findings, we hypothesize that an optimal plantation allowing expression of complementary remediation functions would include B. juncea for extraction of Ag, in combination with F. arundinacea for stabilization of Cu and S. miyabeana for extraction of Zn.

Studies and evaluation of the potential toxicity of decabromodiphenyl ethane to five aquatic and sediment organisms.

The potential toxicity of decabromodiphenyl ethane (DBDP-Ethane) was explored in 5 types of organisms residing in the water column and/or sediment, e.g. Oncorhynchus mykiss, Pseudokirchneriella subcapitata, Daphnia magna, Chironmus riparius, and Lumbriculus variegates. Fish, algae or Daphnia were unaffected by acute exposures to water accommodated fractions of 110mg DBDP-Ethane/L. Chronic exposure to DBDP-Ethane at the highest dose tested, 5000mg/kg dry sediment, did not affect midge mean development times, emergence or development rates or oligochaete survival, reproduction or dry weight. The chronic EC50, LOEC and NOEC were ≥5000mg/kg in the two sediment species. Applying an assessment factor of 50, the unbounded predicted no effect concentration (PNEC(sediment)) was 100mg/kg dry sediment. The calculated PNEC indicates DBDPE-Ethane presents little risk to sediment organisms. These results add to DBDP-Ethane's existing database in the terrestrial compartment and mammals.

Agonistic behavior in groups of limbic epileptic male rats: pattern of brain damage and moderating effects from normal rats.

Different ratios of normal male rats and male rats in which limbic seizures had been induced by a single systemic injection of lithium and pilocarpine were housed in groups of six. The group ratios ranged along the continuum from all normal rats to all experimental rats. The average numbers of episodes of boxing, biting and mounting--thrusting per rat per hour per group were recorded by direct observation (red light) for 1 h during the midscotophase. Groups that contained less than two normal rats exhibited significantly elevated amounts of agonistic (boxing, biting) behavior but not mounting behavior. Multiple regression analyses showed that combinations of neuronal loss within only two to three areas accommodated at least 50% of the variance in the numbers of these behaviors.

Three year injury crash records of new licensees with suspensions or invalidity periods lasting 90 days or more.

A subset of new licensees, namely the ones with suspensions or invalidity periods of at least 90 days are studied. This subpopulation is comprised of 3,550 men and 1,295 women for whom the study file contains age, gender, licensing exam performance, and the dates all police reported crashes for the first three years after licensing. This group is compared with the complementary subpopulation of 53,069 men and 58,464 women. The average injury crash rate per year, not prorated, is 0.057 for men and 0.033 for women, about twice the rate for those without lengthy suspensions. These licensees are older, have lower success rates at licensing exams, and have a longer learning period than the others. Separate logistic-normal regression models for men and for women are estimated for the probability of a collision in a year using the available explanatory variables.

Successful goniosynechialysis for angle-closure glaucoma after vitreoretinal surgery.

PURPOSE: To describe 2 cases of long-term successful clinical outcome after goniosynechialysis for secondary angle-closure glaucoma after vitreoretinal surgery. METHODS: Case reports. Goniosynechialysis was performed bilaterally in 1 patient and unilaterally in another for uncontrolled angle-closure glaucoma after vitreoretinal surgery. RESULTS: Angle reopening was performed 2 to 4 months after initial closure. After follow-up of between 3 and 5 years, intraocular pressure has remained below 21 mm Hg without medication in all three eyes. CONCLUSION: Goniosynechialysis should be considered a viable therapeutic alternative to filtration surgery in selected patients with a recent history of angle-closure glaucoma after vitreoretinal surgery.

Impact of diabetes on crash risks of truck-permit holders and commercial drivers.

OBJECTIVE: The U.S. and some Canadian government agencies have waived commercial license restrictions for some insulin-using diabetic drivers. However, the U.S. Federal Highway Administration is no longer giving waivers. Scientific evidence to support such regulations has been sparse. This article presents detailed analyses of crash risks for users and nonusers of insulin among diabetic truck-permit holders in Québec, Canada. RESEARCH DESIGN AND METHODS: Diabetic truck-permit holders were group-matched by age to a random sample of healthy permit holders. Data on permits, medical conditions, and crashes involving 13,453 permit holder-years in 1987-1990 were extracted from the files of the public insurer for automobile injuries in Québec. Additional health status data were obtained from the provincial public health insurer. A telephone survey was conducted to collect data on driving patterns and exposure. Risk ratios were estimated using negative binomial regression models. RESULTS: Risk ratios for crashes vary by category of diabetes. Permit holders for single-unit trucks (STs) who are diabetic without complications and not using insulin have an increased crash risk of 1.68 when compared with healthy permit holders of the same permit class. When controlling for risk exposure, commercial drivers with an ST permit and the same diabetic condition have an increased risk of 1.76. Insulin use is not associated with higher crash risk. CONCLUSIONS: The increased crash risk for the group with uncomplicated diabetes not using insulin is a new finding. The lack of consistent increases in crash risks among diabetic commercial drivers with complications or who use insulin may be a "healthy worker effect" masking the real risk, because these licensees have a lower participation rate as professional drivers.

Antinociceptive effects of the neuroactive steroid, 3alpha-hydroxy-5alpha-pregnan-20-one and progesterone in the land snail, Cepaea nemoralis.

Results of investigations with vertebrates have implicated neuroactive steroids and in particular 5alpha-reduced metabolites of progesterone such as 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP/3A5P and originally allopregnanolone) in the rapid modulation of diverse functions including that of nociceptive sensitivity. These effects have been indicated to involve modulation of GABA receptors. Results of recent phylogenetic studies have revealed the presence of GABA receptors in invertebrates that may also be subject to modulation by steroids and neuroactive steroids. The present study examined the effects of the neuroactive steroid, 3alpha-hydroxy-5alpha-pregnan-20-one, as well as progesterone on aversive thermal (nociceptive) responses in a mollusc, the land snail, Cepaea nemoralis. 3alpha-Hydroxy-5alpha-pregnan-20-one had significant dose-related (0.01-1.0 microg) antinociceptive effects in Cepaea increasing the latency of response to a 40 degrees C surface, with maximum effects being evident 15-30 min after administration. These effects of 3alpha-hydroxy-5alpha-pregnan-20-one were stereospecific, with the stereoisomer 3beta-hydroxy-5alpha-pregnan-20-one (3B5P) failing to affect nociceptive responses. Progesterone also had significant dose-related (0.10-10 microg) antinociceptive effects that, however, were delayed in onset and relatively prolonged (60-120 min), suggestive of the formation of active metabolites. The presence of endogenous progesterone (12.36+/-0.17 ng/g tissue) was ascertained by a radioimmunoassay further supporting a functional role for steroids in Cepaea. The antinociceptive effects of 3alpha-hydroxy-5alpha-pregnan-20-one and progesterone were blocked by the GABA antagonists, bicuculline and picrotoxin, while being relatively insensitive to opioid and N-methyl-D-aspartate antagonists. These results suggest an early evolutionary development and phylogenetic continuity of neuroactive steroid and GABA involvement in the mediation of nociception.

Ventricular dilation over several weeks following induction of excitotoxic (systemic lithium/pilocarpine) lesions: potential role of damage to the substantia nigra reticulata.

Time-dependent atrophy of cerebral space and enlargement of the lateral ventricles were noted in healthy rats 1 to 100 days after the induction of seizures by a single systemic injection of lithium and pilocarpine. The rate of atrophy was most strongly correlated (0.90) with the log (base 10) of the time in days. Most of the degeneration had occurred within about 20 to 30 days after the seizure-induced brain trauma. Concomitant reduction in the area of the substantia nigra reticulata was the most powerful predictor of ventricular enlargement at the level of the caudate-putamen.

Specific IgE-dependent sensitization, atopy, and bronchial hyperresponsiveness in apprentices starting exposure to protein-derived agents.

Atopy, specific IgE sensitization, and bronchial hyperresponsiveness (BHR) were examined in a cohort of 769 apprentices starting career programs in animal health or veterinary medicine (Group 1), pastry making (Group 2), and dental hygiene (Group 3). The hypothesis were that: (1) a proportion of subjects can be "sensitized" although no significant specific occupational exposure has occurred; and (2) there is a relationship between baseline specific sensitization to work-related antigens and host characteristics. Skin tests were administered using 11 common inhalants and specific allergens, including six laboratory animal extracts, three cereal antigens, alpha-amylase, and latex. Methacholine challenge tests were performed. The prevalence of atopy was 54.4% in Group 1, 58.1% in Group 2, and 52.5% in Group 3. Skin reactivity to work-specific proteins was as follows: laboratory animal proteins, 13.8% in Group 1, 14.0% in Group 2, and 15.6% in Group 3. No subject was sensitized to alpha-amylase, whereas 1.2% in Group 1, 5% in Group 2, and 4.1% in Group 3 were sensitized to flour. Five subjects reacted to latex. BHR (PC20 < or = 8 mg/ml) was present in 17.6%, 21.2%, and 14.8% of subjects in Groups 1, 2, and 3, respectively. Specific sensitization was associated with positive skin reactions to common allergens, work-related symptoms, and BHR. These results suggest that students starting career programs with exposure to high-molecular-weight allergens have a low but substantial frequency of specific sensitization to work-related allergens that is related to atopy and BHR.

The Feather of Hope Aboriginal AIDS Prevention Society: a community approach to HIV/AIDS prevention.

Infection with the human immunodeficiency virus (HIV) is a complex and challenging issue for Aboriginal people in Canada. There is a need for HIV/AIDS prevention programs that address the specific needs of Canadian Aboriginal communities in a culturally accepted manner. The Feather of Hope Aboriginal AIDS Prevention Society provides culturally sensitive HIV prevention programs to Aboriginal communities in Alberta. The community development approach used by the Society emphasizes empowerment at the individual and group level. This approach is congruent with the shift to self-determination by Aboriginal people throughout Canada.

Medical conditions and the severity of commercial motor vehicle drivers' road accidents.

In this research we studied the association between commercial motor vehicle drivers' medical conditions and crash severity. Some aspects of medical condition were considered. To our knowledge, no study has ever isolated this association. The severity of a crash was measured by the total number of victims (injured and dead). We estimated nonlinear regression models (specifically, Poisson and negative binomial) which incorporated, simultaneously, information on drivers' characteristics, crash circumstances and health status, in order to isolate the association between health status and crash severity. Our results show that crashes of truck drivers with binocular vision problems and bus drivers with hypertension are more severe than those of healthy drivers. No other medical condition considered in this study was significantly associated with crash severity. Many variables describing crash circumstances were also significant.

Association between intermale social aggression and cellular density within the central amygdaloid nucleus in rats with lithium/pilocarpine-induced seizures.

Aggressive behaviors (numbers of bites/hour) within groups (ns = 8) of normal rats and rats in which seizures had been induced by a single systemic injection of lithium/pilocarpine were observed for 11 successive, 1-hr, periods. Mean numbers of neurons and glial cells were counted for 10 different nuclei of the amygdala for 16 different brains (8 control; 8 seizure). Although there was no significant difference found between rats with chronically induced seizures and controls for the numbers of neurons per area within the central medial amygdaloid nucleus, the neuronal density was correlated significantly (.92) with mean numbers of bites per hour for the chronically epileptic group only. The hypothesis that seizure-induced damage within proximal amygdaloid nuclei disinhibits the central nucleus and encourages aggression was supported.

Medical conditions, risk exposure, and truck drivers' accidents: an analysis with count data regression models.

Recent studies do not agree on the possible relationship between medical conditions and traffic safety; most of them do not control for exposure factors. This problem has become more pertinent for scientific studies because of litigation that showed that present regulations about access to driver permits might contravene human rights legislation. In our study, we estimate the effect of different medical conditions on truck drivers' distributions of accidents. Our data and our models permit simultaneous control for age; medical conditions; exposure factors measured by hours, kilometer, and qualitative factors; and other characteristics of truck drivers. Our results show that diabetic truck drivers of the permit class for straight trucks have more accidents than drivers in good health. No other studied medical condition has a significant effect on individual accident distributions. Many risk exposure variables are also significant. The effect of age is discussed in detail.

Immunogenic and antigenic properties of a heptavalent high-molecular-weight O-polysaccharide vaccine derived from Pseudomonas aeruginosa.

We investigated the chemical and immunologic properties of a heptavalent vaccine composed of high-molecular-weight polymers of the lipopolysaccharide (LPS) O polysaccharides representative of the most common clinical isolates of Pseudomonas aeruginosa. We also evaluated the serum antibody response to nonvaccine strains of P. aeruginosa, including strains expressing structural variants (subtype strains) of the O side chain of the vaccine strains. The polyvalent vaccine, prepared under conditions suitable for human use, contained low levels of contaminants and passed preclinical safety and toxicity tests required for human use. Chemical analyses indicated that individual polysaccharides were composed of both O-side chain and core sugars. Following immunization of C3H/HeN mice and New Zealand White rabbits, antibody titers against vaccine components increased between 32- and 200-fold. Antibodies reactive with LPS isolated from smooth and rough nonvaccine strains were also elicited. Analysis of the opsonic activity against the known LPS subtype variants of the vaccine strains revealed a variable pattern of killing, which ranged from opsonic killing of > or = 69% of bacterial cells representing all subtype variants within a serogroup to opsonization of only a minority of the subtype variant strains. Mouse and rabbit immune sera showed different patterns of opsonic activity against subtype strains, indicating that different epitopes on these antigens are immunodominant in the representatives of these two animal species tested. The polyvalent vaccine was effective at eliciting antibodies to vaccine components in mice and rabbits, but it remains to be determined if the current heptavalent formulation contains sufficient components to provoke human antibodies reactive with a majority of clinical strains of P. aeruginosa.

Transcutaneous and end-tidal carbon dioxide pressures should be measured during pediatric polysomnography.

Pediatric obstructive sleep apnea (OSAS) is characterized by partial airway obstruction, alveolar hypoventilation, and elevated arterial CO2 (PaCO2). Thus, a reliable, practical method of estimating CO2 is needed for pediatric polysomnography. Therefore, we measured both transcutaneous CO2 (PtcCO2) and end-tidal CO2 (PETCO2) in 15 pediatric polysomnographic evaluations. Sleep state, the highest PtcCO2, and the highest PETCO2 were recorded for 5,159 thirty-second epochs. Although PtcCO2 and PETCO2 were available for 78.5 and 73.0% of epochs, respectively, at least one estimator was available for 92% of the epochs. One infant who would not tolerate a nasal sampling catheter had no PETCO2 data. For 13 of 14 studies there was a relatively constant difference between PtcCO2 and PETCO2. The difference between PtcCO2 and PETCO2 was within 4 mm Hg in 63.9% of 3,072 epochs. Across 14 studies, mean PtcCO2 exceeded mean PETCO2 by 2.8 +/- 3.0 mm Hg, and it was within 4 mm Hg in 10 studies. In three subjects, PETCO2 was intermittently or consistently less than PtcCO2 because of tachypnea, increased physiologic dead space, or severe partial airway obstruction; in one subject PtcCO2 exceeded PETCO2 for undetermined reasons during one electrode application. The results of this study indicate that PtcCO2, as well as PETCO2, should be measured during pediatric polysomnography. By utilizing both PtcCO2 and PETCO2 there was a 70% reduction in the number of epochs that could not be assessed for hypoventilation. For an individual subject or electrode application there was a constant, and usually close, relationship, between PtcCO2 and PETCO2.(ABSTRACT TRUNCATED AT 250 WORDS)

Neck injuries among belted and unbelted occupants of the front seat of cars.

This article, part of a recently completed research project on safety belts, presents results on neck injuries. A total of 3927 injured front-seat occupants (drivers and passengers) involved in two-car crashes were studied. Among them, 725 sustained neck sprains (ICD-9 code 847.0); some of them may have sustained other injuries as well. The more serious injuries to the cervical spine were more prevalent among the unbelted occupants. Neck sprains were relatively more numerous among belted occupants compared with unbelted ones, with a relative risk estimate of 1.68. Similar results hold also for subsets of the data on different types of collisions; the relative risks ranged from 1.39 to 2.42. A log linear model was constructed for the odds ratio (neck sprain vs. no neck sprain) taking into account the following factors: (1) seatbelt use, (2) direction of impact, (3) authorized speed limit, and (4) vehicle weight. The resulting relative risk estimate (belted vs. unbelted) became 1.58. The results raise questions about seatbelts and their protection against neck sprains.