Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution.

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an "environmentally friendly" fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O(3)), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O(3) concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O(3) concentrations will reach 100 parts per billion (10(9)) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.

Altered Schaedler flora mice: A defined microbiota animal model to study the microbiota-gut-brain axis.

Despite considerable attention, the mechanisms by which the microbiota affect brain function and host behaviour via the gut-brain axis remain undefined. Identifying microbe-specific pathways that influence neuronal function and bi-directional communication between the gut microbiota and the host central nervous system is challenging due to the extreme microbial diversity in the gut of conventionally-reared mice. Herein, we describe the use of the altered Schaedler flora (ASF) mouse model as an alternative to conventionally-reared and germ-free animals. Colonized with only 8 bacterial species, use of ASF mice greatly simplifies the examination of microbiota-host interactions. We assessed the extent to which behaviour differed between mice with a limited consortium of bacteria compared with a complex, conventional microbiota. The elevated plus maze and open-field assays were utilized to assess murine behaviour. Histological analysis of ileum and colon was performed to evaluate intestinal morphology, and 16 s rRNA gene taxonomic profiling was performed to determine host-stress induced changes in fecal microbial communities. Behavioural and serum corticosterone differences were observed between ASF and conventionally-reared mice, while no differences were found between the intestinal morphology of these two groups. The stress of the behavioural tests induced significant changes in the ASF fecal microbial community but not in that of the conventionally-reared mice. In contrast to the conventionally-reared mice, the results indicated that the ASF mice displayed a marked anxiogenic-like behaviour. These data indicate that ASF mice represent a unique model to elucidate mechanisms governing microbiota-gut-brain communication affecting behaviour.

New plasmids carrying antibiotic-resistance cassettes.

A series of new plasmid vectors is described that carry gene cassettes imparting resistance to the antibiotics chloramphenicol (CmR), kanamycin (KmR), tetracycline (TcR) and spectinomycin/streptomycin (Sp/SmR). The gene cassettes are symmetrically flanked by several restriction sites. In addition, several restriction sites that are normally found internal to the gene cassettes have been eliminated, thereby expanding the number of restriction enzymes available to excise an intact antibiotic-resistance gene. The gene cassettes are carried by high-copy-number plasmids that confer ampicillin resistance (ApR).

Assembly of a cytoplasmic membrane protein in Escherichia coli is dependent on the signal recognition particle.

Targeting of the cytoplasmic membrane protein leader peptidase (Lep) and a Lep mutant (Lep-inv) that inserts with an inverted topology compared to the wild-type protein was studied in Escherichia coli strains that are conditional for the expression of either Ffh or 4.5S RNA, the two components of the E. coli SRP. Depletion of either component strongly affected the insertion of both Lep and Lep-inv into the cytoplasmic membrane. This indicates that SRP is required for the assembly of cytoplasmic membrane proteins in E. coli.

Dexamethasone treatment fails to reduce oxygen-induced lung injury in the preterm guinea pig. Effects on pulmonary inflammation and antioxidant status.

Dexamethasone (10 mg/kg/day) or vehicle was administered in a randomized, controlled fashion to 3-day preterm guinea pigs exposed to either 21% oxygen or 95% oxygen for 72 hr and maintained in room air for a further 96 hr. Treatment with dexamethasone had no effect on survival of preterm pups maintained in either 21% or 95% O2. Dexamethasone treatment reduced the growth rate of pups, the effect occurring earlier (0-3 days) in 21% O2-treated pups than in 95% O2-treated pups (5-7 days). Exposure to 95% O2 reduced the survival rate of preterm animals (73% vs 100%, P < 0.05). Surviving pups developed acute lung injury, characterized by the accumulation of a protein-rich exudate in the alveoli and an infiltration of inflammatory cells, particularly neutrophils into the lung. Dexamethasone treatment attenuated the pulmonary inflammatory cell infiltration, in particular neutrophils, both during oxygen exposure (16.4 x 10(4) vs 9.4 x 10(4)/mL; P < 0.05) and following return to ambient conditions (28.0 x 10(4) vs 5.1 x 10(4)/mL; P < 0.05). Elastase activity in bronchoalveolar lavage fluid, which was primarily of neutrophil origin, was unchanged by dexamethasone treatment. Dexamethasone-treated pups had increased pulmonary antioxidant enzyme activities (Cu/Zn-superoxide dismutase; Mn-superoxide dismutase, catalase and glutathione peroxidase) during recovery from oxidative injury. Although there was both a marked reduction in numbers of neutrophils in the lung and elevated pulmonary antioxidant enzyme activities in dexamethasone-treated pups, the degree of microvascular permeability, as determined by both the lung wet weight/dry weight ratio and the presence of plasma proteins in the lavage fluid, was unchanged. Combined, these results imply that dexamethasone, although capable of blunting the influx of neutrophils to the hyperoxia-exposed lung and inducing antioxidant defences in the immature lung, cannot modify the progression of acute oxygen-induced injury of the immature lung.

Protein intake in pregnancy, placental glucocorticoid metabolism and the programming of hypertension in the rat.

Hypertension is strongly predicted by a low birthweight:placental weight ratio. Two independent models have been described to explain this association; less than optimal maternal protein nutrition leading to fetal undernutrition, or glucocorticoid excess. Pregnant rats were fed diets containing 18 per cent casein (control) or 9 per cent casein, balanced for energy. On day 20 of gestation the pregnancies were terminated and placentae collected for determination of 11 beta-hydroxysteroid dehydrogenase (11 beta HSD) activity. Placental 11 beta HSD normally protects the fetus from the effects of maternal glucocorticoids. Activity was specifically attenuated by mild protein restriction (33 per cent in activity), whilst activities of glucocorticoid-insensitive control enzymes were unchanged and glucocorticoid-inducible glutamine synthetase activity was increased (27 per cent), relative to activity in placentae from control animals. The nutritional manipulation during pregnancy significantly increased systolic blood pressure (17 mmHg) in the resulting offspring in early adulthood. A possible common pathway whereby maternal environmental factors may influence fetal and placental growth and programme disease is inferred.

Urinary desmosine, elastolysis, and lung disease.

Desmosine is an amino acid specific to elastin. Animal studies suggest that urinary desmosine (UD) represents endogenous elastin degradation. Therefore, UD has previously been used to investigate endogenous elastolysis, but was not elevated in subjects with chronic obstructive airways disease (COAD), although accelerated pulmonary elastolysis is thought to contribute to COAD. We have investigated whether this reflects large day-to-day and between-subject variation in UD and whether, in man, dietary desmosine contributes significantly to that in urine. Mean 24-hour UD output (over 5 consecutive days) from 10 asymptomatic subjects (5 males) was higher in males than females (77.4 +/- 9.6 and 40.2 +/- 5.0 nmol/24 hours, respectively; mean +/- SD, P less than .001), but not significantly different when expressed in terms of creatinine (micrograms desmosine/100 mg creatinine: males, 2.5 +/- 0.4; females, 3.1 +/- 0.8; mean +/- SD). The lowest between-subject variation was observed when the mean of 5 days' 24-hour UD values was analyzed on the basis of gender (coefficient of variation [CV], 12.5%); when gender was not considered, the least between-subject variation was found for the mean of 5 days' desmosine/creatinine analysis (CV, 24.5%). Approximately 1% of dietary desmosine (ingested as [3H]elastin and [3H] desmosine) was excreted in the urine within 24 hours, contributing approximately 15% of UD while on a normal diet. Although ingestion of a low elastin diet (less than 1/10 desmosine/24 hours than a normal diet) resulted in lower within-subject variation in 24-hour UD excretion (mean CV decreased from 31.5% to 20.2%), the between-subject CV and UD levels did not alter.(ABSTRACT TRUNCATED AT 250 WORDS)

Green fluorescent protein--a bright idea for the study of bacterial protein localization.

Use of the green fluorescent protein (GFP) of Aequorea victoria as a reporter for protein and DNA localization has provided sensitive, new approaches for studying the organization of the bacterial cell, leading to new insights into diverse cellular processes. GFP has many characteristics that make it useful for localization studies in bacteria, primarily its ability to fluoresce when fused to target polypeptides without the addition of exogenously added substrates. As an alternative to immunofluorescence microscopy, the expression of gfp gene fusions has been used to probe the function of cellular components fundamental for DNA replication, translation, protein export, and signal transduction, that heretofore have been difficult to study in living cells. Moreover, protein and DNA localization can now be monitored in real time, revealing that several proteins important for cell division, development and sporulation are dynamically localized throughout the cell cycle. The use of additional GFP variants that permit the labeling of multiple components within the same cell, and the use of GFP for genetic screens, should continue to make this a valuable tool for addressing complex questions about the bacterial cell.

Evaluation and management of nutritional status before surgery.

Preoperative evaluation of all patients should include evaluation of nutritional status. Factors of greatest clinical usefulness are nutritional history correlated with the clinical situation, and measures of body height and weight, serum albumin concentration, and muscle mass. Depressed immune function suggested by a lack of skin test reactivity to standard antigens may correlate with the risk of postoperative complications and death, but further studies are required to determine the specific relation of nutrient deficiencies and immune function. Micronutrient deficiencies must be identified and corrected rapidly. Nutritional support in patients with nutritional deficiencies should be started preoperatively either by enteral or intravenous techniques and continued postoperatively.

In utero exposure to maternal low protein diets induces hypertension in weanling rats, independently of maternal blood pressure changes.

The association between maternal nutrition, fetal growth and the later development of hypertension was investigated in the rat. Animals were habituated to diets containing 18% (control) or 9% (low) protein by weight. The rats were mated and maintained on the diets until the end of pregnancy. Lactating dams were transferred onto standard chow diet. Systolic blood pressure was determined in male and female weanling offspring, using an indirect tail-cuff method. To assess the direct effects of low protein diets upon blood pressure of adult animals, a group of male and female rats were fed 18% or 9% protein for 14 days. Blood pressure was determined at the beginning and end of the feeding period. Blood pressure was additionally assessed over 14 days in pregnant rats fed control or low protein diets. Low protein diets did not alter systolic blood pressure in adult male or female rats. The blood pressures of pregnant females fed 18% or 9% protein diets did not significantly differ at any stage of pregnancy. Rats fed 9% protein diets gave birth to significantly smaller pups. Litter sizes were unaltered, and no differences in perinatal mortality were observed. Pups exposed to maternal low protein in utero had higher systolic blood pressure at the age of 4 weeks, when compared to control pups. The phenomenon was observed in both male and female offspring. Blood pressures at 4 weeks of age were strongly associated with maternal protein intake (r = -0.55). Associations were also noted between blood pressure and maternal weight at mating (r = 0.48), and weight gain in pregnancy (r = -0.30). Fetal exposure to maternal low protein diets induces hypertension in rats. The phenomenon is observed early in life and is independent of sex and the influence of maternal blood pressure. The low protein diet itself did not produce an increase in the blood pressure of adult rats.

Neutrophils and oxygen-induced lung injury: a case of when a few is still too many.

The role of neutrophils in acute oxidative lung injury in preterm babies is presently unclear, with some investigators maintaining they contribute to tissue injury while others believe they do not. The aim of the present study was to determine whether neutropenia, induced by a specific neutrophil antibody, influenced the time course or extent of oxygen-induced injury of the immature lung. Preterm guinea pigs, delivered by caesarean section at 65 days' gestation (term=68 days), were injected intraperitoneally with either control serum (CS) or neutrophil antiserum (NAS; 200 µl/100 g body weight) once daily for 5 days. Pups were exposed to 95% oxygen for the first 72 h, and then allowed to recover in 21% oxygen for the subsequent 48 h. Groups of treated animals were also maintained in 21% oxygen for 5 days. Lungs were examined by bronchoalveolar lavage (BAL) at 72 h or 120 h. In CS-treated pups, exposure to 95% oxygen increased both the number of circulating neutrophils and those recovered by BAL at both 72 h and 120 h. Protein concentration in BAL fluid, an index of lung microvascular permeability, and BAL elastase and ß-glucuronidase activities, indices of neutrophil activation, were significantly increased in pups exposed to 95% oxygen. Pups exposed to 95% oxygen and treated with NAS showed a decrease in numbers of circulating neutrophils (72 h, 9.53 vs 0.66 x 10(5)/ml, P<0.0005; 120 h, 4.9 vs 0.08 x 10(5)/ml, P<0.0005) and BAL fluid neutrophils (72 h, 3.1 vs 0.7 x 10(5)/ml, P<0.05; 120 h, 12.4 vs 3.8 x 10(5)/ml, P<0.05). BAL protein concentration, neutrophil elastase and ß-glucuronidase activities in hyperoxia-exposed pups were similar following treatment with either CS or NAS. Although the number of circulating neutrophils were markedly depleted and expansion of the alveolar neutrophil pool was restricted in NAS-treated pups, the neutrophils recruited to the lung were activated and could have contributed to the increase in microvascular permeability in hyperoxia-exposed pups.

Oxygen-induced lung injury in the pre-term guinea pig: the role of leukotriene B4.

Leukotriene B4 (LTB4) has been reported to promote the formation of lung oedema when infused into the pulmonary circulation of adult animals. The present study evaluated the hypothesis that LTB4 was responsible, in part, for the oedema that develops during oxidative injury of the immature lung. Significant increases were found in LTB4 concentration in bronchoalveolar lavage fluid obtained from pre-term guinea pig pups maintained in 95% oxygen for 48 h (P < 0.05) and 72 h (P < 0.05) compared to pups maintained in 21% oxygen. Cellular analysis of lavage fluid revealed a concurrent influx of neutrophils into the hyperoxic-injured lung at these times. The protein concentration of lavage fluid was also increased by 48-h hyperoxia exposure indicating elevated pulmonary microvascular permeability. In a second series of experiments, pups exposed to 95% oxygen (and 21% oxygen controls) were treated with a specific LTB4 antagonist (U-75302), at either 0.5, 1.5 or 3.0 mg 100 g body wt to ascertain if LTB4 played a role in either neutrophil recruitment or oedema formation in the immature lung. The number of neutrophils recovered in bronchoalveolar lavage fluid was significantly reduced, compared to vehicle-treated pups, in pups treated with U-75302, at both 1.5 and 3.0 mg/100 g body wt but not 0.5 mg/100 g body wt. Histopathological analysis of pups treated with 1.5 mg U-75302/100 g body wt revealed fewer neutrophils in the pulmonary interstitium (198 vs. 218 mm-2, P < 0.05). The extent of lung microvascular permeability, elevated by hyperoxic exposure, was modulated by increasing concentrations of U-75302. Specifically, treatment with 0.5, 1.5 and 3.0 mg U-75302/100 g body wt reduced microvascular permeability by 17, 67 and 98%, respectively. In conclusion, LTB4 plays an important role in oedema formation in acute oxidative injury of the immature lung and this is mediated, in part, through neutrophils.

Chromosomal integration and expression of the Escherichia coli K88 gene cluster in Salmonella enterica ser. Choleraesuis strain 54 (SC54).

Attempts to develop live vaccines to protect against enterotoxigenic Escherichia coli (ETEC) infection by induction of both cell-mediated and mucosal immunity, and serum antibody responses have included use of recombinant Salmonella strains that produce K88 fimbrial antigens (Hone et al., 1988; Attridge et al., 1988; Morona et al., 1994). However, none of the recombinant Salmonella vectors has been licensed by the United States Department of Agriculture (USDA) for use as a live vaccine in pigs in the United States. A variant of Salmonella enterica ser. Choleraesuis strain 54 (SC54) is currently used as a safe and effective intranasal attenuated live vaccine in pigs. In order to expand the efficacy of this live vaccine strain, we sought to modify strain SC54 to express the K88 antigens of ETEC. To accomplish this, a plasmid-based system was used to integrate the K88 gene cluster into the chromosome of strain SC54 by site-specific recombination. The K88 antigens were expressed by strain SC54, and the gene cluster was stably maintained in the host.

Sulphur dioxide: a potent glutathione depleting agent.

Sulphur dioxide (SO2) is an air pollutant implicated in the initiation of asthmatic symptoms. Glutathione (GSH) has been proposed to play a role in detoxification of SO2 through the sulfitolysis of glutathione disulphide (GSSG) to S-sulphoglutathione (GSSO3-). Rats were exposed to concentrations of SO2 between 5 and 100 ppm for 5 hr a day between 7 and 28 days. Lung injury as assessed by bronchoalveolar lavage and tissue GSH status were evaluated. SO2 5 ppm failed to elicit any lung injury or inflammatory response but did deplete GSH pools in lung, liver, heart and kidney. Activities of gamma-glutamylcysteine synthetase (GCS), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GRed) in lung were lowered relative to those in control animals. In liver, GRed activity was decreased. SO2 50 ppm exposure also failed to elicit injury or inflammation but did lower inflammatory cell numbers in the circulation. Rats exposed to 50 ppm SO2 maintained tissue GSH status, but activities of GCS, GPx, GRed and gamma-glutamyltranspeptidase in lung and hepatic GRed and GPx were significantly lower than in control rats. Unaltered GST activity in lung and liver was suggestive of an impairment of the sulfitolysis reaction in these animals, perhaps through lower substrate flux through the GPx reaction, as GSSO3- is a known inhibitor of GST in the rat. Rats exposed to 100 ppm SO2 exhibited evidence of inflammation (120-fold increase in neutrophil numbers recovered in lavage fluid) and like the 5 ppm exposed rats had lower tissue GSH concentrations and GSH-related enzyme activities in lung. We conclude that sulfitolysis of GSSG does occur in vivo during SO2 exposure and that SO2, even in the absence of pulmonary injury, is a potent glutathione depleting agent.

Value driven innovation in medical device design: a process for balancing stakeholder voices.

The innovation process has often been represented as a linear process which funnels customer needs through various business and process filters. This method may be appropriate for some consumer products, but in the medical device industry there are some inherent limitations to the traditional innovation funnel approach. In the medical device industry, there are a number of stakeholders who need to have their voices heard throughout the innovation process. Each stakeholder has diverse and unique needs relating to the medical device, the needs of one may highly affect the needs of another, and the relationships between stakeholders may be tenuous. This paper describes the application of a spiral innovation process to the development of a medical device which considers three distinct stakeholder voices: the Voice of the Customer, the Voice of the Business and the Voice of the Technology. The process is presented as a case study focusing on the front-end redesign of a class III medical device for an orthopedics company. Starting from project initiation and scope alignment, the process describes four phases, Discover, Envision, Create, and Refine, and concludes with value assessment of the final design features.

Adsorption of polar and nonpolar compounds onto complex nanooxides with silica, alumina, and titania.

Adsorption of low-molecular adsorbates (nonpolar hexane, nitrogen, weakly polar acetonitrile, and polar diethylamine, triethylamine, and water) onto individual (silica, alumina, titania), binary (silica/alumina (SA), silica/titania (ST)), and ternary (alumina/silica/titania, AST) fumed oxides was studied to analyse the effects of morphology and surface composition of the materials. Certain aspects of the interfacial phenomena dependent on the structural characteristics of oxides were analysed using calorimetry, (1)H NMR, and Raman spectroscopies, XRD, and ab initio quantum-chemical calculations. The specific surface area S(BET,X)-to-S(BET,N(2)) ratio (X is an organic adsorbate) changes from 0.68 for hexane adsorbed onto amorphous SA8 (degassed at 200 degrees C) to 1.85 for acetonitrile adsorbed onto crystalline alumina (degassed at 900 degrees C). These changes are relatively large because of variations in orientation, lateral interactions, and adsorption compressing of molecules adsorbed onto oxide surfaces. Larger S(BET,X)/S(BET,N(2)) values are observed for mixed oxides with higher crystallinity of titania or/and alumina phases in larger primary nanoparticles with greater surface roughness and hydrophilicity. Polar adsorbates can change the structure of aggregates of oxide nanoparticles that can, in turn, affect the results of adsorption measurements.

Sonoelectrochemical deposition of calcium phosphates on carbon materials: effect of current density.

Calcium phosphate (CaP) coatings on carbon fabric substrate were produced by sonoelectrodeposition at different current densities (5, 8, 13, 20 and 34 mA/cm2). The surface morphology and chemical composition of the coatings were characterized by SEM, Raman and FTIR spectra. The results showed that at 5 mA/cm2 current density, the coating exhibits plate-like morphology, indicating an octacalcium phosphate (OCP) phase was pre-formed in the deposits and then converted into hydroxyapatite (HA). When the current density was increased to 8 mA/cm2 and higher, the coatings exhibited needle-like morphology corresponding to a HA phase. Furthermore, the sonoelectrodeposited CaP coating exhibited denser and more uniform structures with smaller crystal sizes as the current density increased. Cathodic reaction mechanisms of CaP coatings on carbon in the sonoelectrochemical processes are proposed to explain the different kinds of calcium phosphate obtained.