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91.
Zeinab I. Khalil Mohsen M. S. Asker Salwa El-Sayed Imam A. Kobbia 《World journal of microbiology & biotechnology》2010,26(7):1225-1231
The goal of the present investigation was to study the effect of pH on growth and biochemical responses of Dunaliella bardawil and Chlorella ellipsoidea when exposed to different pH values. The two tested microalgae could grow in a wide range of pH (4–9 for D. bardawil and 4–10 for C. ellipsoidea). The dry weight gain and the biochemical components of D. bardawil were greatly enhanced at pH 7.5. In contrast, dry weight and carbohydrate content of C. ellipsoidea attained their maximum values at the alkaline pH. On the other hand, the protein content of C. ellipsoidea recorded its highest value at pH 4, while the pigment content of the same alga was highest at pH 4, 6, and 7.5 and decreased
at alkaline pH. Both pH 6 and pH 9 stimulated the accumulation of β-carotene, vitamin E and vitamin C in D. bardawil, with the highest values of the three compounds recorded at pH 9. In the case of C. ellipsoidea, β-carotene content increased at pH 6 and pH 10 as compared with the control, but the amount of β-carotene was much higher
at pH 6 than at pH 10. Vitamin E content was higher in C. ellipsoidea cells at pH 10 than at pH 6. Both pH 6 and pH 10 caused a significant decline in vitamin C content of C. ellipsoidea. 相似文献
92.
Our aim in this study was to investigate the effect of aging on the capacity of HDLs to promote reverse cholesterol transport. HDLs were isolated from plasma of young (Y-HDL) and elderly (E-HDL) subjects. HDL-mediated cholesterol efflux was studied using THP-1 and J774 macrophages. Our results show that E-HDLs present a lower capacity to promote cholesterol efflux than Y-HDLs (41.7 +/- 1.4% vs. 49.0 +/- 2.2%, respectively; P = 0.013). Reduction in the HDL-mediated cholesterol efflux capacity with aging was more significant with HDL(3) than HDL(2) (Y-HDL(3), 57.3 +/- 1% vs. E-HDL(3), 50.9 +/- 2%; P = 0.012). Moreover, our results show that ABCA1-mediated cholesterol efflux is the more affected pathway in terms of cholesterol-removing capacity. Interestingly, the composition and structure of HDL revealed a reduction in the phosphatidylcholine-sphingomyelin ratio (E-HDL, 32.7 +/- 2.7 vs. Y-HDL, 40.0 +/- 1.9; P = 0.029) and in the phospholipidic layer membrane fluidity in E-HDL compared with Y-HDL as well as an alteration in the apolipoprotein A-I structure and charge. In conclusion, our results shown that E-HDLs present a reduced capacity to promote cholesterol efflux, principally through the ABCA1 pathway, and this may explain the increase of the incidence of cardiovascular diseases observed during aging. 相似文献
93.
Sahar F. Deraz Martin Hedström Eva Nordberg Karlsson Sara Linse Ashraf A. Khalil Bo Mattiasson 《World journal of microbiology & biotechnology》2007,23(7):911-921
Lactobacillus acidophilus DSM 20079 is the producer of a novel bacteriocin termed acidocin D20079. In this paper, a partial sequence of this peptide
is determined, together with data on its secondary structure. A modification of the MRS-growth medium (replacing the detergent
Tween 80 with oleic acid), was shown to improve the production level of the peptide by one order of magnitude, as well as
to stabilize the activity level. Addition of a detergent (Tween 20, less interfering in mass spectrometric analysis), was
however necessary for solubilization of the purified acidocin D20079. Digestion of the peptide followed by de-novo sequencing
of generated fragments, allowed determination of a partial sequence consisting of 39 of the totally estimated 65 residues.
Acidocin D20079 has a high content of glycine residues, hydrophobic residues, and acidic residues. No modified amino acids
were found. Edman degradation, and C-terminal sequencing failed, suggesting that the peptide may be cyclic, and a novel member
of class IIc bacteriocins. Circular dichroism spectroscopy and secondary structure prediction showed random coil conformation
in aqueous solution, but secondary structure was induced in the presence of sodium-dodecyl sulfate. The data could be fitted
assuming 2–13% of the residues to be in α-helix and 23–27% of the residues to be in β-strand conformation. This indicates
that a membrane/membrane-mimicking hydrocarbon–water interface induces an active conformation. 相似文献
94.
Muriel Fartoukh Antoine Khalil Laurence Louis Marie-France Carette Bernard Bazelly Jacques Cadranel Charles Mayaud Antoine Parrot 《Respiratory research》2007,8(1):11-9
Background
Limited data are available concerning patients admitted to the intensive care unit (ICU) for severe haemoptysis. We reviewed a large series of patients managed in a uniform way to describe the clinical spectrum and outcome of haemoptysis in this setting, and better define the indications for bronchial artery embolisation (BAE).Methods
A retrospective chart review of 196 patients referred for severe haemoptysis to a respiratory intermediate care ward and ICU between January 1999 and December 2001. A follow-up by telephone interview or a visit.Results
Patients (148 males) were aged 51 (± sd, 16) years, with a median cumulated amount of bleeding averaging 200 ml on admission. Bronchiectasis, lung cancer, tuberculosis and mycetoma were the main underlying causes. In 21 patients (11%), no cause was identified. A first-line bronchial arteriography was attempted in 147 patients (75%), whereas 46 (23%) received conservative treatment. Patients who underwent BAE had a higher respiratory rate, greater amount of bleeding, persistent bloody sputum and/or evidence of active bleeding on fiberoptic bronchoscopy. When completed (n = 131/147), BAE controlled haemoptysis in 80% of patients, both in the short and long (> 30 days) terms. Surgery was mostly performed when bronchial arteriography had failed and/or bleeding recurred early after completed BAE. Bleeding was controlled by conservative measures alone in 44 patients. The ICU mortality rate was low (4%).Conclusion
Patients with evidence of more severe or persistent haemoptysis were more likely to receive BAE rather than conservative management. The procedure was effective and safe in most patients with severe haemoptysis, and surgery was mostly reserved to failure of arteriography and/or early recurrences after BAE. 相似文献95.
Oligonucleotides containing 7-deaza-2'-deoxyxanthosine (1) and 2'-deoxyxanthosine (2) were prepared. The 2-(4-nitrophenyl)ethyl group is applicable for 7-deazaxanthine protection that is removed with DBU by beta-elimination, while the deprotection of the allyl residue with Pd (0) catalyst failed. Contrarily, the allyl group was found to be an excellent protecting group for 2'-deoxyxanthosine (2). The base pairing of nucleosides 1 and 2 with the four canonical DNA constituents as well as with 3 within the 12-mer duplexes is studied. 相似文献
96.
Shehla Khalil Bijay Ranjan Mirdha Sanjeev Sinha Ashutosh Panda Yogita Singh Anju Joseph Manorama Deb 《The Korean journal of parasitology》2015,53(6):705-712
Intestinal parasitic infections are one of the major causes of diarrhea in human immunodeficiency virus (HIV) seropositive individuals. Antiretroviral therapy has markedly reduced the incidence of many opportunistic infections, but parasite-related diarrhea still remains frequent and often underestimated especially in developing countries. The present hospital-based study was conducted to determine the spectrum of intestinal parasitosis in adult HIV/AIDS (acquired immunodeficiency syndrome) patients with or without diarrhea with the levels of CD4+ T-cell counts. A total of 400 individuals were enrolled and were screened for intestinal parasitosis. Of these study population, 200 were HIV seropositives, and the remaining 200 were HIV uninfected individuals with or without diarrhea. Intestinal parasites were identified by using microscopy as well as PCR assay. A total of 130 (32.5%) out of 400 patients were positive for any kinds of intestinal parasites. The cumulative number of parasite positive patients was 152 due to multiple infections. A significant association of Cryptosporidium (P<0.001) was detected among individuals with CD4+ T-cell counts less than 200 cells/μl. 相似文献
97.
Osama Mohamed ElShfei El-Azazy Nadra-Elwgoud Mohamed Ibrahim Abdou Amal Iskander Khalil Maha Khaled Al-Batel Qais Abdulrazak Habeeb Majeed Adawia Abdul-Ruhman Henedi Laila Mohamed Azad Tahrani 《The Korean journal of parasitology》2015,53(3):279-287
Stray cats are a common feature roaming the streets and alleys of Kuwait; they could be a source of parasites, including trematodes, that affect humans. A survey was conducted to identify feline trematodes and throw the light on their public health significance in Kuwait. Out of 240 stray cats trapped from different localities of Kuwait from June 2011 to May 2012, 59 (24.6%) were found to be infected with 14 species of trematodes. The most common were trematodes of the genus Heterophyes, particularly H. heterophyes and H. dispar that were found in respectively 15.8% and 10.8% of the cats examined. Other trematodes recorded, with lower prevalences, were Heterophyes nocens (2.9%), Haplorchis taichui (3.8%), Stictodora sawakinensis (2.1%), Stellantchasmus falcatus (1.6%), Echinochasmus japonicus (1.6%), and Mesostephanus dottrensi (1.3%). Centrocestus cuspidatus, Galactosomum fregatae, Ascocotyle sp., Mesostephanus appendiculatus, Haplorchis yokogawai, and Pygidiopsis genata showed the lowest prevalence (0.4%) and intensity. The majority of the trematodes are recorded for the first time in Kuwait and even in the Gulf region. The study reveals that stray cats are good indicators of fish-borne trematodes in the environment. As all trematodes recovered are zoonotic, their significance to public health should be considred. 相似文献
98.
A. I. Khalil M. S. Hassouna H. M. A. El-Ashqar M. Fawzi 《World journal of microbiology & biotechnology》2011,27(10):2359-2369
Changes in physical, chemical and microbial parameters were investigated during the composting of municipal sewage sludge.
Raw sewage sludge (30% dry matter) was mixed with compost from sewage sludge (85% dry matter) in 3:1 ratio (v/v). The mixture
was divided into 4 windrows which were composted under the same conditions except the turning factor. The turning was every
7, 10, 15 days and according to the temperature which must be (55–65°C) for windrow 1 (W1), windrow 2 (W2), windrow 3 (W3)
and windrow 4 (W4), respectively. Water was added to adjust the moisture content (40–60%). The composting process consisted
of 2 periods; fermentation (12 weeks) and maturation (4 weeks). The results showed that the temperature reached the maximum
after 12 weeks for W1 and 11 weeks for W2, W3 and W4 and then decreased. The final compost was nearly odourless and black,
especially in case of W4. The general trend indicates a decrease in organic matter, organic carbon and nitrogen (N), whereas
ash, potassium (K) and phosphorus (P) increased and consequently C/K and C/P ratios decreased. There was a slight increase
in C/N ratio. The pH increased and then decreased to near neutrality at the end. The mesophilic bacteria increased during
the fermentation period and decreased after that, whereas the thermophilic ones increased with increasing of temperature,
decreased after 2 weeks and increased again during the fermentation period and then decreased. The mesophilic and thermophilic
fungi were present during the first week and disappeared after that. The final compost was pathogens-free as indicated by
the counts of coliforms and Salmonella. 相似文献
99.
Rapid and reproducible genomic changes can be induced during the early stages of the life of nascent allopolyploid species. In a previous study, it was shown that following allopolyploidization, cytosine methylation changes can affect up to 11% of the wheat genome. However, the methylation patterns around transposable elements (TEs) were never studied in detail. We used transposon methylation display (TMD) to assess the methylation patterns of CCGG sites flanking three TE families (Balduin, Apollo, and Thalos) in the first four generations of a newly formed wheat allohexaploid. In addition, transposon display (TD), using a methylation-insensitive restriction enzyme, was applied to search for genomic rearrangements at the TE insertion sites. We observed that up to 54% of CCGG sites flanking the three TE families showed changes in methylation patterns in the first four generations of a newly formed wheat allohexaploid, where hypermethylation was predominant. Over 70% of the changes in TMD patterns occurred in the first two generations of the newly formed allohexaploid. Furthermore, analysis of 555 TE insertion sites by TD and 18 cases by site-specific PCR revealed a full additive pattern in the allohexaploid, an indication for lack of massive rearrangements. These data indicate that following allopolyplodization, DNA-TE insertion sites can undergo a significantly high level of methylation changes compared with methylation changes of other genomic sequences. 相似文献
100.
Susan R. Kahn Ian Shrier Stan Shapiro Adrielle H. Houweling Andrew M. Hirsch Robert D. Reid Clive Kearon Khalil Rabhi Marc A. Rodger Michael J. Kovacs David R. Anderson Philip S. Wells 《CMAJ》2011,183(1):37-44