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81.
The concentrations of essential amino acids in three, undigested invertebrate diets collected from the Clark Fork River (CFR) for cutthroat trout were similar to each other, but were c. 25–75% less than Artemia that were exposed to a mixture of arsenic, copper, cadmium, lead and zinc in the laboratory. The Artemia diet appeared less palatable and the texture, quantity and appearance of the intestinal contents differed between fish fed the Artemia and CFR diets. The Pb% in the fluid fraction of the intestinal contents was greater for the Artemia (29%) than for the CFR diets (10–17%), and the Cu% in the amino acid plus metal fraction of the intestinal contents was greater for the Artemia (78%) than for two of the three CFR diets (67% and 70%). Intestinal contents of fish fed invertebrate diets collected from various sites on the Coeur d'Alene River (CDA), Idaho, were similar in texture, quantity, and appearance. For fish fed the CDA diets, differences in the distribution of metals among fractions of the digestive fluids appeared to be related to concentrations of metals in the invertebrate diets. Pb% was lowest of all metals in the fluid portion of the intestinal contents. However, >80% of all metals in the hind gut were associated with the particulate fraction where they may still be available for uptake through pinocytosis.  相似文献   
82.
The Firehole River (FHR) in Yellowstone National Park (YNP) is a world-renowned recreational fishery that predominantly includes rainbow trout (RBT,Oncorhynchus mykiss) and brown trout (BNT,Salmo trutta). The trout populations apparently are closed to immigration and have been self-sustaining since 1955. Inputs from hot springs and geysers increase the temperature and mineral content of the water, including elevating the boron (B) concentrations to a maximum of 1 mg B/L. Both RBT and BNT reside in warm-water reaches, except when the water is extremely warm (≥25°C) during midsummer. They spawn in late fall and early winter, with documented spawning of BNT in the cold-water reach upstream from the Upper Geyser Basin and of RBT in the Lower Geyser Basin reach, where water temperatures presumably are the warmest; however, successful recruitment of RBT in waters containing 1 mg B/L has not been demonstrated conclusively. Thus, we began investigating the relationships among temperature, B concentrations, other waterquality parameters, and the distribution and reproduction of trout in the FHR in spring 1997. However, atypical high water flows and concomitant lower than historical temperatures and B concentrations during summer 1997 preclude conclusions about avoidance of high B concentrations.  相似文献   
83.
After 20% total body surface scalding inducing 3d degree burn in rats the following parameters were studied in ebb and flow phases, as well as in burn disease, 2 hours, 2 and 7 days postburn: atomic absorption spectrophotometric study of the serum and myocardial Ni levels; the effect of Ni ions (10(-8)-10(-4) M/l) in vitro on total coronary resistance in the isolated perfused rat heart; the effect of alpha and beta adrenergic blocking agents (phenoxibenzamine, oxprenolol) on Ni-induced coronary vasoconstriction; electron cytochemical study of the ultrastructural changes of the myocardium 7 days after scalding. It was found that: During the first 2-3 hours after scalding or bleeding there was a significant elevation of serum Ni level which levelled off by the end of the first week. Total coronary resistance (TCR) increasing effect of Ni ions was significantly augmented during the first 2-3 hours after burn and bleeding (ebb phase). In the scalded group it decreased to the control value by the 2-3d day (flow phase) and increased again a week later (burn disease). In the scalded groups in vivo pretreatment with oxprenolol (10(-4) g/kg) completely inhibited the Ni induced coronary spasm. PBZ treatment in vitro (10(-5) M/l) had similar effect in the three postburn periods tested. Ultrastructural changes and intracellular Ni-dimetilglyoxim complexes could be detected. Oxprenolol treatment continuously applied from the 4th day postburn (2 X 0.5 mg/kg) prevented the development of myocardial damage, while the electron dense complexes containing Ni were still detectable. In view of our previous data we assume that the endogenous Ni increase in the serum after burn may be cardiopathogenic. The phasic changes of the sensitivity of the coronary vessels to Ni ion and the similarity of the effects of alpha and beta adrenergic blocking agents may be explained by the alterations in the neuroendocrine system and metabolic disturbances.  相似文献   
84.
Dracaena leaf proliferosis is a newly reported disease affecting Dracaena sanderiana in Egypt. A cause and effect relationship between this disease and the fungus,Fusarium proliferatum var. minus has been established. In addition to D. sanderiana the fungus was found to be pathogenic, when tested in the laboratory, to several other members of the family Liliaceae. While the in vitro growth of the fungus is optimum at 25 °C, symptom expression is best at 30°C. Twelve fungicides were tested for their in vitro effect on fungal growth. Benlate, Rubigan, Saprol, Cercobin and Vitavax-200 came first on the list and inhibited growth at 2.5, 12.0, 55.0, 75.0, and 94.0 μg/ml, respectively. Although, Benlate was the most effective fungicide in this respect it failed to demonstrate similar effect on disease development when applied to plants artificially inoculated with the fungus. Fungal growth was completely inhibited on PDA medium by a bacterium belonging to Bacillus sp. but when the bacterium at a concentration of 1 × 1011 cell/ml was applied 24 h before, at the same time with, or 24 h after inoculation no control of the disease was achieved. Naturally-infected plants could, however, be freed from infection when subjected to a hot air treatment at 35 ± 5 °C during day time and 25 ± 5° C at night for 3 months.  相似文献   
85.
A rabbit heart membrane fraction enriched in sarcoplasmic reticulum was incubated in a reaction mixture containing [gamma-32P]ATP. The catalytic subunit of cyclic AMP-dependent protein kinase enhanced the 32P-labelling of both phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate. Ca2 +-calmodulin also increased the 32P-incorporation into both polyphosphoinositides. Upon SDS gel-electrophoretic analysis of the membrane proteins, phospholamban was found to be concurrently phosphorylated by the exogenous catalytic subunit as well as by an endogenous Ca2+-calmodulin-dependent protein kinase.  相似文献   
86.
BackgroundDiarrheal disease is the second leading cause of disease in children less than 5 y of age. Poor water, sanitation, and hygiene conditions are the primary routes of exposure and infection. Sanitation and hygiene interventions are estimated to generate a 36% and 48% reduction in diarrheal risk in young children, respectively. Little is known about whether the number of households sharing a sanitation facility affects a child''s risk of diarrhea. The objective of this study was to describe sanitation and hygiene access across the Global Enteric Multicenter Study (GEMS) sites in Africa and South Asia and to assess sanitation and hygiene exposures, including shared sanitation access, as risk factors for moderate-to-severe diarrhea (MSD) in children less than 5 y of age.Methods/FindingsThe GEMS matched case-control study was conducted between December 1, 2007, and March 3, 2011, at seven sites in Basse, The Gambia; Nyanza Province, Kenya; Bamako, Mali; Manhiça, Mozambique; Mirzapur, Bangladesh; Kolkata, India; and Karachi, Pakistan. Data was collected for 8,592 case children aged <5 y old experiencing MSD and for 12,390 asymptomatic age, gender, and neighborhood-matched controls. An MSD case was defined as a child with a diarrheal illness <7 d duration comprising ≥3 loose stools in 24 h and ≥1 of the following: sunken eyes, skin tenting, dysentery, intravenous (IV) rehydration, or hospitalization. Site-specific conditional logistic regression models were used to explore the association between sanitation and hygiene exposures and MSD. Most households at six sites (>93%) had access to a sanitation facility, while 70% of households in rural Kenya had access to a facility. Practicing open defecation was a risk factor for MSD in children <5 y old in Kenya. Sharing sanitation facilities with 1–2 or ≥3 other households was a statistically significant risk factor for MSD in Kenya, Mali, Mozambique, and Pakistan. Among those with a designated handwashing area near the home, soap or ash were more frequently observed at control households and were significantly protective against MSD in Mozambique and India.ConclusionsThis study suggests that sharing a sanitation facility with just one to two other households can increase the risk of MSD in young children, compared to using a private facility. Interventions aimed at increasing access to private household sanitation facilities may reduce the burden of MSD in children. These findings support the current World Health Organization/ United Nations Children''s Emergency Fund (UNICEF) system that categorizes shared sanitation as unimproved.  相似文献   
87.
Empathy covers a wide range of phenomena varying according to the degree of cognitive complexity involved; ranging from emotional contagion, defined as the sharing of others’ emotional states, to sympathetic concern requiring animals to have an appraisal of the others’ situation and showing concern-like behaviors. While most studies have investigated how animals reacted in response to conspecifics’ distress, dogs so far have mainly been targeted to examine cross-species empathic responses. To investigate whether dogs would respond with empathy-like behavior also to conspecifics, we adopted a playback method using conspecifics’ vocalizations (whines) recorded during a distressful event as well as control sounds. Our subjects were first exposed to a playback phase where they were subjected either to a control sound, a familiar whine (from their familiar partner) or a stranger whine stimulus (from a stranger dog), and then a reunion phase where the familiar partner entered the room. When exposed to whines, dogs showed a higher behavioral alertness and exhibited more stress-related behaviors compared to when exposed to acoustically similar control sounds. Moreover, they demonstrated more comfort-offering behaviors toward their familiar partners following whine playbacks than after control stimuli. Furthermore, when looking at the first session, this comfort offering was biased towards the familiar partner when subjects were previously exposed to the familiar compared to the stranger whines. Finally, familiar whine stimuli tended to maintain higher cortisol levels while stranger whines did not. To our knowledge, these results are the first to suggest that dogs can experience and demonstrate “empathic-like” responses to conspecifics’ distress-calls.  相似文献   
88.
In this study, the human cerebrospinal fluid (CSF) proteome was mapped using three different strategies prior to Orbitrap LC-MS/MS analysis: SDS-PAGE and mixed mode reversed phase-anion exchange for mapping the global CSF proteome, and hydrazide-based glycopeptide capture for mapping glycopeptides. A maximal protein set of 3081 proteins (28,811 peptide sequences) was identified, of which 520 were identified as glycoproteins from the glycopeptide enrichment strategy, including 1121 glycopeptides and their glycosylation sites. To our knowledge, this is the largest number of identified proteins and glycopeptides reported for CSF, including 417 glycosylation sites not previously reported. From parallel plasma samples, we identified 1050 proteins (9739 peptide sequences). An overlap of 877 proteins was found between the two body fluids, whereas 2204 proteins were identified only in CSF and 173 only in plasma. All mapping results are freely available via the new CSF Proteome Resource (http://probe.uib.no/csf-pr), which can be used to navigate the CSF proteome and help guide the selection of signature peptides in targeted quantitative proteomics.Cerebrospinal fluid (CSF)1 surrounds and supports the central nervous system (CNS), including the ventricles and subarachnoid space (1). About 80% of the total protein amount in CSF derives from size-dependent filtration of blood across the blood-brain barrier (BBB), and the rest originate from drainage of interstitial fluid from the CNS (24). Because CSF is in direct contact with the CNS, it should be a promising source for finding biomarkers for diseases in the CNS (5).Mapping studies characterizing the human CSF proteome and peptidome has previously been carried out using various experimental designs, including both healthy and disease-affected individuals (516). A total of 2630 proteins were detected in normal CSF by immunoaffinity depletion of high abundant proteins followed by strong cation exchange fractionation and LC-MS (5), whereas proteome and peptidome analyses of human CSF (collected for diagnostic purposes and turned out normal) by gel separation and trypsin digestion followed by LC-MS analysis have shown 798 proteins and 563 peptide products (derived from 91 precursor proteins) (6). In another publication, Pan et al. combined several proteomics studies in CSF from both normal subjects and subjects with neurological diseases and created a dataset of 2594 identified proteins (16). But in general, the availability and usefulness of published data from proteome mapping experiments is scarce, and the format of the data often makes searching and comparison across datasets difficult. Thus, organizing the data in online databases would greatly benefit the scientific community by making the data more accessible and easier to query. Current online databases containing MS data for CSF include the Sys-BodyFluid, with a total of 1286 CSF proteins from six studies (17). The proteome identifications database (PRIDE) (18) includes 19 studies on human CSF, but none reporting more than 103 identified proteins.Glycosylation is one of the most common post-translational modifications (PTMs), and many known clinical biomarkers as well as therapeutic targets are glycoproteins (1925). Furthermore, glycosylation plays important roles in cell communication, signaling, aging, and cell adhesion (26, 27). Nevertheless, there are few studies on glycoprotein identification in CSF. One study identified 216 glycoproteins in CSF using both lectin affinity and hydrazide chemistry (8), and another reported 36 N-linked and 44 O-linked glycosylation sites, from 23 and 22 glycoproteins respectively, by enriching for sialic-acid containing glycopeptides (28).Considering the sparse information about the CSF proteome available in public repositories, we have combined several proteomics approaches to create a map of the global CSF proteome, the CSF glycoproteome, and the respective plasma proteome from a pool of 21 (20 for the plasma pool) neurologically healthy individuals. The large amount of data generated through these four datasets (with linked and complementary information) would not easily be accessible through existing repositories. We therefore developed the open access CSF Proteome Resource (CSF-PR, www.probe.uib.no/csf-pr), an online database including the detailed data from the four different proteomics experiments described in this study. CSF-PR will be particularly useful in guiding the selection of appropriate signature peptides for the development of targeted CSF protein assays.  相似文献   
89.
HGF and phorbol ester induce the scattering of HepG2 cells. Recently, we have reported that the motility and morphological responses that accompany this process require the activation of Erk1/Erk2 MAP kinases, and phosphatidylinositol 3-kinase contributes to the activation of Erk1/Erk2 in HGF-induced cells. The cell scattering-associated appearance of a high-M(r) (>300 kDa) protein pair has also been observed, and has been proven to be a sensitive marker of the intensity of Erk1/Erk2 activation. Our present study demonstrates that in HGF-induced cells protein kinase C and phosphatidylinositol 3-kinase regulate oppositely the expression of these cell scattering-associated proteins. While in phorbol ester-treated cells the sustained activation of protein kinase C is essential for this expression, in HGF-induced cells the inhibition of protein kinase C with bisindolylmaleimide I stimulates the expression. Protein kinase C reduces the HGF-induced phosphorylation of Erk1/Erk2, and in this way it can limit the intensity of Erk1/Erk2-dependent gene-expression  相似文献   
90.
The modulation of phosphoinositide 3-kinase (PI3K) activity influences the quality of cellular responses triggered by various receptor tyrosine kinases. Protein kinase C (PKC) has been reported to phosphorylate signalling molecules upstream of PI3K and thereby it may affect the activation of PI3K. Here, we provide the first evidence for a direct effect of a PKC isoenzyme on the activity of PI3K. PKCalpha but not PKCepsilon phosphorylated the catalytic subunit of the p110alpha/p85alpha PI3K in vitro in a manner inhibited by the PKC inhibitor bisindolylmaleimide I (BIM I). The incubation of PI3K with active PKCalpha resulted in a significant decrease in its lipid kinase activity and this effect was also attenuated by BIM I. We conclude that PKCalpha is able to modulate negatively the lipid kinase activity of the p110alpha/p85alpha PI3K through the phosphorylation of the catalytic subunit.  相似文献   
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