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1.
The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks.  相似文献   
2.
A unique event in bacterial epidemiology was the emergence of the El Tor biotype of Vibrio cholerae O1 and the subsequent rapid displacement of the existing classical biotype as the predominant cause of epidemic cholera. We demonstrate that when the El Tor and classical biotypes were cocultured in standard laboratory medium a precipitous decline in colony forming units (CFU) of the classical biotype occurred in a contact dependent manner. Several lines of evidence including DNA release, microscopy and flow cytometric analysis indicated that the drastic reduction in CFU of the classical biotype in cocultures was not accompanied by lysis, although when the classical biotype was grown individually in monocultures, lysis of the cells occurred concomitant with decrease in CFU starting from late stationary phase. Furthermore, uptake of a membrane potential sensitive dye and protection of genomic DNA from extracellular DNase strongly suggested that the classical biotype cells in cocultures retained viability in spite of loss of culturability. These results suggest that coculturing the classical biotype with the El Tor biotype protects the former from lysis allowing the cells to remain viable in spite of the loss of culturability. The stationary phase sigma factor RpoS may have a role in the loss of culturability of the classical biotype in cocultures. Although competitive exclusion of closely related strains has been reported for several bacterial species, conversion of the target bacterial population to the viable non-culturable state has not been demonstrated previously and may have important implications in the evolution of bacterial strains.  相似文献   
3.
Sternal malformation/vascular dysplasia complex was described by Hersch et al. in 1985. The principle findings include cleft of the sternum covered by an atrophic skin, a midline abdominal raphe and hemangiomatosis. The inheritance pattern seems to be sporadic. We report a newborn baby with sternal defect, cleft lip and palate, supraumbilical raphe and hemangiomas.  相似文献   
4.
A number of substrates were tested for the cultivation of microorganisms to produce a host of enzymes. The effect of different substrates (wheat and rice straw, sugar cane waste, wood waste), incubation temperatures (20–40°C), initial pH levels (3.5–9.0), incubation periods (0–72 hours) and nitrogen sources (ammonium sulfate, urea, peptone, yeast extract, sodium nitrate) on growth and α-amylase activity was studied for the native and mutant strains. Maximum enzyme activity was observed at 1.5% wheat straw for Aspergillus niger FCBP-198 and An-Ch-4.7 and at 2% wheat straw for An-UV-5.6, with sodium nitrate as a principle nitrogen source. The optimum temperature for maximum enzyme activity was 30°C for the parental strain, while An-UV-5.6 and An-Ch-4.7 thrived well at 32.5°C. The best conditions of pH and incubation duration were 4.5 and 48 hours, respectively, for all the strains. Mass production under preoptimized growth conditions demonstrated the suitability of wheat straw for swift mycelial colonization and viability.  相似文献   
5.
New polymeric Zn(salen) complex was employed in the enantioselective phenylacetylene addition to aldehydes and ketones to produce corresponding chiral secondary propargylic alcohols with yields (up to 96%) and enantioselectivity (up to 72%) and tertiary propargylic alcohols with yields (up to 79%) and enantioselectivity (up to 68%) at room temperature, with added advantage of four times reuse with retention of enantioselectivity.  相似文献   
6.
Aminolytic kinetic resolution (AKR) of trans-stilbene oxide and trans-beta-methyl styrene oxide proceeded smoothly under microwave irradiation using chiral dimeric and polymeric Cr(III) salen complexes as efficient catalysts, giving regio-, diastereo-, and enantioselective anti-beta-amino alcohols in high yields (49%) and chiral purity (ee up to 94%) in case of 4-methylaniline within 2 min. The kinetic resolution system is approximately five times faster than traditional oil bath heating at 70 degrees C and 420 times faster than the reaction conducted at room temperature with concomitant recovery of respective chirally enriched epoxides (ee, 92%) in excellent yields (up to 48%). The catalyst 1 worked well in terms of enantioselectivity than the catalyst 2, but both the catalysts were easily recovered and reused five times with the retention of its efficiency.  相似文献   
7.
Rutilus frisii kutum (Kamensky 1901) is one of the economically important fishes that migrate for spawning to rivers in the Caspian Sea. However, the fish populations have slowly decreased in recent years. The declining of these resources has resulted from some activities by the Iranian Fisheries Organization (IFO is responsible for stock enhancement) to catch some broodstocks of Rutilus frisii kutum from their natural spawning rivers. The broodstocks are caught for artificial propagation of the fish. Artificial propagations are carried out every year to produce fingerlings to be released into the rivers in the Caspian Sea. In recent years, total catch of this fish have greatly fluctuated due to the disruption of the natural spawning grounds and over fishing. The substantial reduction to 1,298 metric tons, the lowest total catch reported in 1984–1985, could be due to over-exploitation of the fishery resources. However, the total catch has increased after the fingerlings release programs started in 1979. The total numbers of Rutilus frisii kutum fingerlings released had increased from 12 million to 225 million in 2002, to 155 million pieces in 2003, to 179 million pieces in 2004, 229 million pieces in 2005, 174 million pieces in 2006, 262 million pieces in 2007 and 187.1 in 2008. The total catch was also increased from 6,417 metric ton to 8,984 metric ton, to 7,036 metric ton, to 9,631 metric ton and 16,117, 17,196, 14,835 in years 2002, 2003, 2004, 2005, 2006, 2007 and 2008, respectively.  相似文献   
8.
Doxorubicin (DOX), an anthracycline used to treat a variety of cancers, is known to generate intracellular reactive oxygen species. Moreover, many patients who have undergone chemotherapy complain of cognitive dysfunction often lasting years after cessation of the chemotherapy. Previously, we reported that intraperitoneal administration of DOX led to elevated TNF-α and oxidative stress in the plasma and brain of mice. However, the mechanisms involved in nontargeted tissue damage remain unknown. In this study, we measured plasma oxidative stress and cytokine levels in patients treated with DOX. We observed increased plasma protein carbonylation and elevation of TNF-α 6 h after DOX administration in the context of multiagent chemotherapy regimens. Importantly, patients not treated coincidentally with 2-mercaptoethane sulfonate (MESNA) showed statistically significantly increased plasma protein-bound 4-hydroxynonenal, whereas those who had been coincidentally treated with MESNA as part of their multiagent chemotherapy regimen did not, suggesting that concomitant administration of the antioxidant MESNA with DOX prevents intravascular oxidative stress. We demonstrate in a murine model that MESNA suppressed DOX-induced increased plasma oxidative stress indexed by protein carbonyls and protein-bound HNE, and also suppressed DOX-induced increased peripheral TNF-α levels. A direct interaction between DOX and MESNA was demonstrated by MESNA suppression of DOX-induced DCF fluorescence. Using redox proteomics, we identified apolipoprotein A1 (APOA1) in both patients and mice after DOX administration as having increased specific carbonyl levels. Macrophage stimulation studies showed that oxidized APOA1 increased TNF-α levels and augmented TNF-α release by lipopolysaccharide, effects that were prevented by MESNA. This study is the first to demonstrate that DOX oxidizes plasma APOA1, that oxidized APOA1 enhances macrophage TNF-α release and thus could contribute to potential subsequent TNF-α-mediated toxicity, and that MESNA interacts with DOX to block this mechanism and suggests that MESNA could reduce systemic side effects of DOX.  相似文献   
9.
Phosphorylation on tyrosine, threonine and serine residues represents one of the most important post-translational modifications and is a key regulator of cellular signaling of multiple biological processes that require a strict control by protein kinases and protein phosphatases. Abnormal protein phosphorylation has been associated with several human diseases including Alzheimer's disease (AD). One of the characteristic hallmarks of AD is the presence of neurofibrillary tangles, composed of microtubule-associated, abnormally hyperphosphorylated tau protein. However, several others proteins showed altered phosphorylation levels in AD suggesting that deregulated phosphorylation may contribute to AD pathogenesis. Phosphoproteomics has recently gained attention as a valuable approach to analyze protein phosphorylation, both in a quantitative and a qualitative way. We used the fluorescent phosphospecific Pro-Q Diamond dye to identify proteins that showed alterations in their overall phosphorylation in the hippocampus of AD vs. control (CTR) subjects. Significant changes were found for 17 proteins involved in crucial neuronal process such as energy metabolism or signal transduction. These phosphoproteome data may provide new clues to better understand molecular pathways that are deregulated in the pathogenesis and progression of AD.  相似文献   
10.
Small model peptides containing N-terminal methionine are reported to form sulfur-centered-free radicals that are stabilized by the terminal N atom. To test whether a similar chemistry would apply to a disease-relevant longer peptide, Alzheimer's disease (AD)-associated amyloid beta-peptide 1-42 was employed. Methionine at residue 35 of this 42-mer has been shown to be a key amino acid residue involved in amyloid beta-peptide 1-42 [A beta1-42]-mediated toxicity and therefore, the pathogenesis of AD. Previous studies have shown that mutation of the methionine residue to norleucine abrogates the oxidative stress and neurotoxic properties of A beta(1-42). In the current study, we examined if the position of methionine at residue 35 is a criterion for toxicity. In doing so, we tested the effects of moving methionine to the N-terminus of the peptide in a synthetic peptide, A beta(1-42)D1M, in which methionine was substituted for aspartic acid at the N-terminus of the peptide and all subsequent residues from D1 to L34 were shifted one position towards the carboxy-terminus. A beta(1-42)D1M exhibited oxidative stress and neurotoxicity properties similar to those of the native peptide, A beta(1-42), all of which are inhibited by the free radical scavenger Vitamin E, suggesting that reactive oxygen species may play a role in the A beta-mediated toxicity. Additionally, substitution of methionine at the N-terminus by norleucine, A beta(1-42)D1Nle, completely abrogated the oxidative stress and neurotoxicity associated with the A beta(1-42)D1M peptide. The results of this study validate the chemistry reported for short peptides with N-terminal methionines in a disease-relevant peptide.  相似文献   
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