Longitudinal Survey of Aeromonas hydrophila and Foodborne Pathogens in a Commercial Aquaponics System.

Aquaponic production of fresh produce is a sustainable agricultural method becoming widely adopted, though few studies have investigated potential food safety hazards within commercial systems. A longitudinal study was conducted to isolate and quantify several foodborne pathogens from a commercial, aquaponic farm, and to elucidate their distribution throughout. The survey was conducted over 2 years on a controlled-environment farm containing Nile tilapia (Oreochromis niloticus) and lettuce (Lactuca sativa). Samples (N = 1,047) were collected bimonthly from three identical, independent systems, and included lettuce leaves, roots, fingerlings (7-126 d old), feces from mature fish (>126 d old), water, and sponge swabs collected from the tank interior surface. Most probable number of generic Escherichia coli were determined using IDEXX Colilert Quanti-Tray. Enumeration and enrichment were used to detect Shiga toxin-producing E. coli (STEC), Salmonella enterica, Listeria monocytogenes, Aeromonas spp., Aeromonas hydrophilia, and Pseudomonas aeruginosa. Generic E. coli, STEC, L. monocytogenes, and S. enterica were not detected in collected samples. P. aeruginosa was isolated from water (7/351; 1.99%), swabs (3/351; 0.85%), feces (2/108; 1.85%), and lettuce leaves (2/99; 2.02%). A. hydrophila was isolated from all sample types (623/1047; 59.50%). The incidence of A. hydrophila in water (X2 = 23.234, p < 0.001) and sponge samples (X2 = 21.352, p < 0.001) increased over time.

Postharvest Reduction of Salmonella enterica on Tomatoes Using a Pelargonic Acid Emulsion.

A novel produce wash consisting of pelargonic acid (PEL) emulsions was tested on tomatoes contaminated with a five-serovar Salmonella enterica cocktail. Ability to reduce contamination on the inoculated tomato surface, as well as mitigation of subsequent cross-contamination to uninoculated tomatoes washed in re-used/spent wash water were examined. Sanitizer efficacy was also examined over 1 and 7 d storage time (8 °C, recommended for red ripe tomatoes) and in the presence of 0.5% (w/v) organic load. PEL performed statistically the same (p ≤ 0.05) at both 30 mM and 50 mM concentrations and resulted in greater than 1, 5 and 6 log CFU/g Salmonella reductions at 0 h, 1 d and 7 d, respectively, when compared to a water-only or no rinse (NR) treatment. This was also a significantly greater reduction than was observed due to chlorine (sodium hypochlorite) and peroxyacetic acid (PAA) at all time points (p ≤ 0.01). Organic load had no impact on sanitizer efficacy for all examined treatments. Finally, PEL had a deleterious impact on tomato texture. At 1 d, ca. 5 N and 7 N were required to achieve tomato skin penetration and compression, respectively, compared to >9 N and 15 N required by all other treatments (p ≤ 0.05). While PEL sanitizers effectively reduced inoculated Salmonella and subsequent transfer to uninoculated tomatoes, reformulation may be necessary to prevent deleterious quality impacts on produce.

Variations in Practice to Therapeutic Monitoring of Tacrolimus following Primary Adult Liver Transplantation.

BACKGROUND: There is limited clinical evidence evaluating the correlation between immunosuppressant monitoring practice and transplant outcomes. OBJECTIVE: To assess current practice of tacrolimus trough monitoring in early post-operative period following liver transplantation (LT), and its impact on outcomes. METHODS: The duration to trough levels (DTT) were calculated in patients undergoing primary LT. The impact of variability in DTT on graft rejection episodes, serum tacrolimus level and renal function was assessed. These results were converted into a drug level estimation tool, which was validated in a prospective cohort of patients. RESULTS: 2946 events in 274 patients were evaluated. The median DTT was 7:19 hrs (range: 27 min to 19:38 hrs). In 72% (2140 events) of the occasions, DTT was <8 hrs. There was a significant (p=0.022) correlation between DTT and tacrolimus level. Despite clinical decisions were taken to modify the dose of tacrolimus based on trough level, neither did DTT affect the average creatinine levels (p=0.923), nor the variability in DTT did affect acute rejection (p=0.914, and 0.712, respectively). A dose estimation tool was developed and applied to validation cohort (n=612), and returned a moderate R(2) value of 0.50. CONCLUSION: There is a significant variation in the "real world" monitoring of tacrolimus with DTT in majority of measurements falling below recommendations; reassuringly, this did not lead to adverse transplant sequelae.

Changes in volumetric BMD of radius and tibia upon antidepressant drug administration in young depressive patients.

OBJECTIVES: To determine longitudinal changes in trabecular volumetric BMD (vBMD) at tibia and radius in young depressive patients under antidepressants using pQCT. METHODS: PQCT data on 26 patients (22 females, 4 males) on serotonin re-uptake inhibitors (SSRI), and 14 patients (12 females, 2 males) on non-SSRI (10 SNRI, 4 TCA) were obtained at 4% and 66% of radius and tibia at baseline and at 12-month. Depression was assessed by Beck Depression Inventory (BDI) at baseline and follow-up. Wilcoxon tests were performed to find longitudinal changes in bone parameters within each group, Mann-Whitney tests to detect differences between groups. RESULTS: The two groups were comparable with regard to age, height and BDI. None of the measured bone parameters changed in the SSRI group. In the non-SSRI group trabecular vBMD increased slightly but significantly from baseline to follow-up at radius and tibia (p<0.03). Between group differences were significant for trabecular BMD at the radius. BDI decreased significantly in both groups by the same amount. CONCLUSIONS: Bone properties were found to be stable over 12 months under therapy with SSRIs. Whether SNRI and TCA indeed increase trabecular vBMD need to be shown in larger cohort.

Long-term effects of supervised exercise training on walking capacity and quality of life in patients with intermittent claudication.

UNLABELLED: Supervised exercise training has been shown to improve walking capacity in several studies of patients with intermittent claudication. However, data on long-term outcome are quite limited. The aim of this prospective study was to evaluate long-term effects of supervised exercise training on walking capacity and quality of life in patients with intermittent claudication. PATIENTS AND METHODS: Sixty-seven consecutive patients with intermittent claudication who completed a supervised 12-week exercise training program were asked for follow up evaluation 39 +/- 20 months after program completion. Pain-free walking distance (PWD) and maximum walking distances (MWD) were assessed by treadmill test and several questionnaires. RESULTS: Forty (60%) patients agreed to participate, 22 (33%) refused participation, and 5 (7%) died during follow-up. PWD and MWD significantly improved at completion of 12-weeks supervised exercise training as compared to baseline (PWD 114 +/- 100 vs. 235 +/- 248, p = 0.002; MWD 297 +/- 273 vs. 474 +/- 359, p = 0.001). Improvement of PWD and MWD could be maintained at follow up (197 +/- 254, p = 0.014; 390 +/- 324, p = 0.035, respectively) with non-smokers showing significantly better sustained PWD and MWD improvement as compared to baseline. Overall, walking capacity correlated with functional status of quality of life. CONCLUSIONS: Major findings of this investigation were that improvement in walking capacity is sustained after completion of supervised exercise training program with best results in patients who quitted or never smoked. Improved walking capacity is associated with increased functional status of quality of life.

Does cartoon movie distraction decrease burned children's pain behavior?

The purpose of this study was to evaluate cartoon movie viewing as a practical and low-cost intervention to decrease burned children's pain behavior during dressing changes. Thirteen children, 4 to 12 years of age, with a mean TBSA burn of 7.9% were assessed using a reversal, single-subject experimental design. The experimental condition consisted of the presentation of a cartoon movie as a nonpharmacologic intervention in conjunction with a standardized analgesic medication. In the control condition children's pain was treated with the standardized analgesic medication only. Behavioral distress was measured during the first six dressing changes postburn with the Observational Scale of Behavioral Distress. No significant effect of cartoon movie distraction on observed behavioral distress in patients was found. Interrater reliability of the Observational Scale of Behavioral Distress was good (kappa =.87-.98). Wound debridement was found to be the most painful part of the dressing change. A simple, easily applicable, and low-cost distraction intervention such as presenting cartoon movies does not seem to be sufficiently powerful to measurably reduce burned children's distress during dressing changes. Findings are based on purely observational data. Inclusion of self-report measures in future studies might reveal intervention effects on anxiety and subjective pain perception.

Magnesium involvement in sleep: genetic and nutritional models.

Alterations of peripheral magnesium (Mg) concentration have been reported in association with several behavioral disorders and sleep organization. Blood Mg regulation is under a strong genetic control, whereas brain Mg regulation does not seem to be affected. We have studied peripheral and central levels of Mg and analyzed sleep in two lines of mice selected for low (MGL) and high (MGH) red blood cell (RBC) Mg levels. The same variables were also studied in C57BL/6J mice before and after 3 weeks of Mg deficiency. Whereas blood Mg was highly affected by the selection, brain Mg exhibited only small differences between the two lines. In contrast, Mg deficiency strongly decreased both central and peripheral Mg levels. Sleep analysis indicated that in both models the amount of paradoxical sleep was lower in mice with higher Mg levels. The amplitude of daily variation in sleep and slow-wave sleep delta power was markedly decreased in MGH line. Quantitative electroencephalogram (EEG) analysis also revealed a faster theta peak frequency in MGH mice, irrespective of behavioral states. Central Mg showed significant correlations with the amount of paradoxical sleep and sleep consolidation. However, because the direction of these correlations was not consistent, it is concluded that optimal, (physiological) rather than high or low, Mg levels are needed for normal sleep regulation.

Blood and brain magnesium in inbred mice and their correlation with sleep quality.

A strong genetic component in the regulation of blood magnesium (Mg) levels has been demonstrated. The regulation and distribution of brain Mg levels, however, have never been assessed. Herein we report on the genetic variation of peripheral and central Mg levels in six inbred strains of mice. In addition, the possible involvement of Mg in sleep regulation was assessed by establishing correlations between Mg and sleep parameters obtained before and after a 6-h sleep deprivation. Although genotype strongly determined blood Mg levels, it did not affect brain Mg, suggesting that central and peripheral Mg are regulated differently. Central Mg displayed a highly structure-specific distribution with frontal cortex having the highest and brain stem the lowest values. Whereas for the amount and distribution of baseline sleep only marginal correlations with Mg were found, Mg contents in four of nine brain structures were highly positively correlated with the length of slow-wave sleep episodes during recovery. This relationship suggests that higher levels of Mg in specific brain sites promote sleep quality as part of a recovery process.

[L-tryptophan plasma levels in treatment resistant depressive states]. / Taux sérique du L-tryptophane dans les états dépressifs résistants.

10 to 30% of depressions are resistant to standard treatment. Different therapeutic strategies are used to treat the resistant depressions. Therefore, before initiating an antidepressant treatment, it would be important to know which patients will probably not respond to a standard treatment. Numerous studies have shown that serotonin is involved in depressive illness and its synthesis in the brain is dependent on the availability of tryprophan from plasma. As tryptophan plasma level is decreased in depression, resistant depressions may also be characterized by alterations of tryptophan plasma level. 141 depressed patients were admitted in our psychiatric unit in Geneva between 1984 and 1990. 36 were diagnosed as treatment resistant depression. Although treatment resistant patients group had more women and a more severe score of depression on the AMDP-4 scale, we did not observe a significant difference in tryptophan plasma level compared to patients who respond to treatment.

Are preventive HIV interventions at airports effective?

BACKGROUND: Few empirical data exist on the impact of preventive human immunodeficiency virus (HIV) interventions on intended and actual sexual behavior of international tourists. The present cross-sectional study is based on a 2 3 2 design. METHODS: The sample consisted of departing and arriving passengers (n = 3100) at Zurich Airport with destinations in countries where heterosexual HIV transmission is dominant. While 41% of the tourists obtained information about safer sex, the remaining 59% without such intervention served as control group. Departing passengers completed a short questionnaire focusing on their planned sexual behavior. Arriving passengers were asked about their actual behavior during the journey. Subjects of the intervention group also evaluated the impact of the consultation. RESULTS: Most travelers appreciated the intervention and reported that they received important information. Members of the intervention group were better informed than those of the control group about the risk of heterosexually transmitted HIV infection (p <.01). They also indicated more often that they could imagine having casual sex abroad (23% vs 16%, p <.01). However, the two groups did not differ with regard to planned condom use or actual sexual behavior. Whereas most of departing passengers indicated that they would use condoms consistently, only half of the passengers who reported casual sex actually did so. Subjects who refused to participate in the intervention tended to consider it as irrelevant and reported less consistent condom use. CONCLUSIONS: Although travel health interventions focusing on casual sex are appreciated and increase the knowledge, they failed to result in significant behavior modification. Future projects should attempt to approach possible risk groups more specifically and to have more impact.

[Not Available]. / Relationship between blood magnesium and psychomotor retardation in drug-free patients with major depression.

In previous reports, we have observed that blood magnesium was significantly higher in drug-free patients with major depression when compared to healthy controls. This was especially true for erythrocyte magnesium. Furthermore, the most severely depressed patients had the highest intracellular magnesium content, showing that intracellular magnesium rate was related to the intensity of symptoms. We report here the results of blood magnesium measured in 88 major depressed patients as compared to 61 controls. We show that the mean erythrocyte and also plasma magnesium contents are both increased in these patients. We observe that about 40% of male and female patients have a very significant increase (25%) in intracellular magnesium content as compared to controls. However, about 60% of the hospitalised depressed patients have normal values. None of the controls has high erythrocyte magnesium. This is less evident concerning the plasma magnesium. No differences are observed between patients when classified according to the intensity of moral pain or anxiety. In contrast, the patients with mild to high psychomotor retardation score, which is an index of hypoexcitability, have significant higher erythrocyte magnesium values compared with other patients. The results of male patients without psychomotor retardation do not differ from control values. Our study suggests that central hypoexcitability might be related to an increase in intracellular magnesium observed at the peripheral level, keeping in mind that hyperexcitability, as observed in various conditions such as stress and cardiovascular disorders, is frequently associated, in contrast, with a decrease in blood magnesium.

Weak association between blood sodium, potassium, and calcium and intensity of symptoms in major depressed patients.

In previous reports, we showed that plasma and erythrocyte magnesium were increased in many drug-free hospitalized depressed patients. Furthermore, we observed that erythrocyte magnesium content was related to the intensity of the symptoms. Highly depressed patients had the highest magnesium values. Today, we report the results of plasma and erythrocyte sodium and potassium, and of total and ultrafilterable plasma calcium in 66 hospitalized patients with major depression compared to 58 healthy controls. No consistent differences in these biochemical parameters are observed between patients when separated according to intensity of anxiety, psychomotor retardation, and moral distress. Plasma sodium is higher and plasma potassium lower in female patients of all subgroups as compared to controls. Both male patients and controls have erythrocyte sodium and potassium levels that are significantly different from those of females. This clearly suggests a separation into genders in such studies. In conclusion--in contrast to blood magnesium--sodium, potassium, and calcium levels do not seem to be related to the intensity of the main clinical symptoms in hospitalized patients with major depression.

Regulation of 5'-AMP-activated protein kinase activity by the noncatalytic beta and gamma subunits.

The mammalian 5'-AMP-activated protein kinase is a heterotrimer consisting of an alpha catalytic subunit and beta and gamma noncatalytic subunits, each of which is represented in a larger isoprotein family, related to the SNF1 kinase and its interacting proteins in yeast. In this study, we have used mammalian cell transfection to compare the activities of the two alpha subunit isoforms, alpha-1 and alpha-2, and to study the influence of the noncatalytic subunits on enzyme subunit association and activity. Expression of epitope-tagged protein subunits in COS7 cells indicates detectable but low level kinase activity for each of the two catalytic alpha subunits. Co-expression of alpha subunits with the beta or gamma subunits modestly increases kinase activity accompanied by the formation of alpha/beta or alpha/gamma heterodimers. Co-expression of all three subunits, however, is accompanied by a 50-110-fold increase in kinase activity with the formation of a heterotrimeric complex. In addition to binding of each noncatalytic subunit to the alpha subunit, the beta and gamma subunits bind to each other, likely resulting in a more stable heterotrimeric complex. The increase in kinase activity associated with expression of this heterotrimer is due both to an increase in enzyme-specific activity (units/enzyme mass) and to an apparent enhanced alpha subunit expression. Co-expression of a catalytically defective alpha subunit or the beta/gamma-binding COOH-terminal domain of the alpha subunit results in reduced heterotrimeric kinase activity. The synergistic positive regulatory roles for both the noncatalytic beta and gamma subunits of 5'-AMP-activated protein kinase contrasts with the Snf1p kinase, where only heterodimers of Snf1p and Snf4p seem to be required for maximum kinase activity.

Identification of a second human acetyl-CoA carboxylase gene.

Acetyl-CoA carboxylase (ACC), an important enzyme in fatty acid biosynthesis and a regulator of fatty acid oxidation, is present in at least two isoenzymic forms in rat and human tissues. Previous work has established the existence of a 265,000 Da enzyme in both the rat and human (RACC265; HACC265) and a higher-molecular-mass species (275,000-280,000 Da) in the same species (RACC280; HACC275). An HACC265 gene has previously been localized to chromosome 17. In the present study, we report cloning of a partial-length human cDNA sequence which appears to correspond to HACC275 and its rat homologue, RACC280, as judged by mRNA tissue distribution and cell-specific regulation of mRNA/protein expression. The gene encoding this isoenzymic form of ACC has been localized to the long arm of human chromosome 12. Thus, ACC is represented in a multigene family in both rodents and humans. The newly discovered human gene and its rat homologue appear to be under different regulatory control to the HACC265 gene, as judged by tissue-specific expression in vivo and by independent modulation in cultured cells in vitro.

Non-catalytic beta- and gamma-subunit isoforms of the 5'-AMP-activated protein kinase.

The mammalian 5'-AMP-activated protein kinase (AMPK) is a heterotrimeric protein consisting of alpha-, beta-, and gamma-subunits. The alpha-subunit is the catalytic subunit and is related to the yeast Snf1p kinase. In this study, we report the cloning of full-length cDNAs for the non-catalytic beta- and gamma-subunits. The rat liver AMPK beta-subunit clone predicts a protein of 30,464 Da, which is related to the Sip1p, Sip2p, and Gal83p subfamily of yeast proteins that interact with Snf1p and are involved in glucose regulation of gene expression. The AMPK beta-subunit, when expressed in bacteria and in mammalian cells, migrates anomalously on SDS gels at an apparent molecular mass of 40 kDa. Rat and human liver AMPK gamma-subunit clones predict a protein of 37,577 Da (AMPK-gamma1), which is related to the yeast Snf4p protein that copurifies with Snf1p and to a larger family of other human AMPK gamma-isoforms. The mRNAs for both AMPK- beta and AMPK-gamma1 are widely expressed in rat tissues, consistent with a broad role for AMPK in cellular regulation. These data reveal a mammalian multisubunit protein kinase strikingly similar to the multisubunit glucose-sensing Snf1 kinase complex. The identification of isoform families for the AMPK subunits indicates the potential diversity of the roles of this highly conserved signaling system in nutrient regulation and utilization in mammalian cells.

Mammalian AMP-activated protein kinase subfamily.

The mammalian 5'-AMP-activated protein kinase (AMPK) is related to a growing family of protein kinases in yeast and plants that are regulated by nutritional stress. We find the most prominent expressed form of the hepatic AMPK catalytic subunit (alpha 1) is distinct from the previously cloned kinase subunit (alpha 2). The alpha 1 (548 residues) and alpha 2 (552 residues) isoforms have 90% amino acid sequence identity within the catalytic core but only 61% identity elsewhere. The tissue distribution of the AMPK activity most closely parallels the low abundance 6-kilobase alpha 1 mRNA distribution and the alpha 1 immunoreactivity rather than alpha 2, with substantial amounts in kidney, liver, lung, heart, and brain. Both alpha 1 and alpha 2 isoforms are stimulated by AMP and contain noncatalytic beta and gamma subunits. The liver alpha 1 isoform accounts for approximately 94% of the enzyme activity measured using the SAMS peptide substrate. The tissue distribution of the alpha 2 immunoreactivity parallels the alpha 2 8.5-kilobase mRNA and is most prominent in skeletal muscle, heart, and liver. Isoforms of the beta and gamma subunits present in the human genome sequence reveal that the AMPK consists of a family of isoenzymes.

Relationship between erythrocyte magnesium, plasma electrolytes and cortisol, and intensity of symptoms in major depressed patients.

53 male and female drug-free major depressed patients were separated into three groups according to the severity of the depression. In the entire regrouped population, plasma and erythrocyte magnesium (Mg) were shown to increase as compared with 48 healthy controls, confirming our previous studies. The middle and highly depressed patients had higher erythrocyte and also plasma Mg levels than either lowly depressed patients or controls. Only, a few differences were noticed in plasma sodium, potassium and calcium (Ca) in the three groups of patients, except for ultrafiltrable plasma Ca, measured for the first time in affective disorders. Thus, erythrocyte and also plasma Mg are shown to be associated with the intensity of the depression. As blood hypomagnaesemia is often related to hyperexcitability, further investigations are actually in process to shown whether hypermagnesaemia might be, in contrast, associated with psychomotor retardation as observed in many depressed patients.

Catalytic subunits of the porcine and rat 5'-AMP-activated protein kinase are members of the SNF1 protein kinase family.

The 5'-AMP-activated protein kinase (AMPK) regulates the fatty acid and sterol synthesizing pathways via phosphorylation of acetyl-CoA carboxylase and HMG-CoA reductase, respectively. Highly purified kinase from porcine liver contains three apparent subunits of molecular mass 63 kDa, 40 kDa and 38 kDa. Peptide sequencing of the 63 kDa protein (AMPK63cat) revealed that this polypeptide is the catalytic subunit of the kinase. Porcine peptide sequences were used to clone by RT-PCR partial length cDNAs for the catalytic domains of the porcine AMPK63cat, and its rat homolog, which were virtually identical in deduced amino acid sequence. Screening of a rat liver cDNA library with these partial length cDNAs and with degenerate oligonucleotides yielded several unique clones, some of which had a 142 bp deletion in the catalytic domain of the kinase. A consensus full-length sequence with a 1.7 kb open reading frame has been constructed from overlapping library and PCR-derived clones. A large mRNA for rat AMPK63cat (8.5 kb) is expressed in nearly all rat tissues, with highest levels detectable in heart and skeletal muscle. Using PCR, the presence of two mRNA species with or without the 142 bp deletion in the catalytic domain was noted in all rat tissues examined. Comparison of the deduced protein sequence of AMPK63cat reveals highly conserved homologies in both the catalytic and non-catalytic domains to several members of the SNF1 kinase family, including kinases from Arabidopsis, barley, rye, and S. cerevesiae, as well as to other mammalian kinases and to a C. elegans kinase. The high evolutionary conservation of both kinase structure and function (metabolite sensing) coupled with their pattern of tissue/organism expression suggest that the mammalian members of this kinase family likely play wider roles than the regulation of cellular lipid metabolism.

Sodium-magnesium exchange in erythrocyte membranes from patients with affective disorders.

The Vmax of erythrocyte sodium-magnesium exchange was measured for the first time in 63 patients suffering from affective disorders and compared to that in 33 healthy subjects. Depressed patients had a significantly higher Vmax (215 +/- 13 vs. 151 +/- 14 mumol/l.cells/h; p < 0.005; mean +/- SEM). This tendency was conserved after division of the 63 patients into three clinical subgroups according to the DSM-III-R criteria. Thirty-four patients from this panel were divided into three subgroups according to the chemical class of the antidepressant drug used and were followed up during a 3-month period of drug treatment. Mood improvement over the 3-month period was associated with a slow increase in Vmax of Na/Mg exchange (delta increase approximately 25 mumol/l.cells/h), except in the subgroup of patients treated with non-tricyclic antidepressants (n = 8). These results are consistent with the previously reported link between high erythrocyte magnesium content and affective disorders. Indeed, enhanced Na/Mg exchange Vmax, which probably results from an increased number of transport units per cell, contributes to the normalization of red blood cell magnesium content correlated with mood improvement.