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71.
Ali Ellafi Ikbel Denden Fethi Ben Abdallah Ines Souissi Amina Bakhrouf 《World journal of microbiology & biotechnology》2009,25(7):1161-1168
In this study, we investigated the survival and adhesion ability of Shigella after their incubation in seawater microcosms at ambient temperature and at 4°C during 1 month. Our results showed that the
number of cells was considerably decreased after this period of stress. In addition, we have revealed some modifications in
the biochemical and enzymatic profiles of stressed cells. These modification were noted by the appearance or/and the disappearance
of some activities. Indeed, antibiotic susceptibility of stressed cells has been changed. Adherence assays to KB cells showed
on increase in the number of adherent cells from 0.7 to 6.7% after 1 month of incubation in seawater. 相似文献
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73.
Mohamed Sellami Ali Châari Imen Aissa Mohamed Bouaziz Youssef Gargouri Nabil Miled 《Process Biochemistry》2013,48(10):1481-1487
Preparation of dopamine derivatives was carried out as a response to the increasing demand for new lipophilized antioxidants in food, cosmetic and pharmaceutical industries. A large series of dopamine esters (DA-C3 to DA-C18:1) with increasing lipophilicity was synthesized using lipase from Candida antarctica (Novozyme 435) as a biocatalyst. The highest conversion yield (52.75%) was reached when caprylic acid (DA-C8) was used as acyl donor. Synthesized compounds were purified and evaluated for their antioxidant activity using the DPPH and the ABTS tests. Results showed that esterification had little effect on radical-scavenging capacity. However, long chain fatty acid esters displayed higher protective effect of oil against oxidation at 70 °C as compared to the parent dopamine or to the BHT. The hemolytic activity of dopamine esters was studied. Middle chain length derivatives (DA-C8 and DA-C12) of dopamine and oleic acid derivative (DA-C18:1) showed the highest hemolytic activity against human erythrocyte. The antimicrobial activities of dopamine esters were also evaluated using well diffusion and minimal inhibition concentration methods. Among all the tested compounds, DA-C8 and DA-C12 exhibited the highest antibacterial activities. These results open up potential applications by using dopamine derivatives as antioxidants and antimicrobial compounds in cosmetic, food and pharmaceutical industries. 相似文献
74.
Hanen Sellami Abir Znazen Afifa Sellami Hela Mnif Nour Louati Soumaya Ben Zarrouk Leila Keskes Tarek Rebai Radhouane Gdoura Adnene Hammami 《PloS one》2014,9(7)
This study was undertaken to determine the prevalence of Chlamydia trachomatis, Mycoplasmas, and Ureaplasmas in semen samples of the male partners of infertile couples and to investigate whether Chlamydia trachomatis could initiate apoptosis in human spermatozoa. A total of 85 males partners of infertile couples undergoing routine semen analysis according to World Health Organization guidelines were included. Specimens were examined for the presence of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum and Ureaplasma parvum by Real time PCR (qPCR). Semen specimens were analysed for the appearance of apoptotic markers (sperm DNA fragmentation, activated caspase 3 levels, mitochondrial membrane potential (ΔΨm)) using flow cytometry. C. trachomatis, N. gonorrhoeae, U. urealyticum, M genitalium were detected in semen samples of 13 (15.2%), 5 (5.8%), 5 (5.8%) and 3 (3.5%) male partners of infertile couples, respectively. M. hominis and U. parvum were detected in semen sample of only one patient (1.1%). The semen of infertile men positive for C. trachomatis showed lower mean of semen count and lower rapid progressive motility (category [a]) of spermatozoa compared to uninfected men with statistically significances (p = 0.02 and p = 0.04, respectively). Flow cytometry analyses demonstrated a significant increase of the mean rate of semen with low ΔΨm and caspase 3 activation of infertile men positive for C. trachomatis compared to uninfected men (p = 0.006 and p = 0.001, respectively). DNA fragmentation was also increased in sperm of infertile men positive for C. trachomatis compared to uninfected men but without statistical significances (p = 0.62). Chlamydial infection was associated to loss of ΔΨm and caspase 3activation. Thus, C. trachomatis infection could be incriminated in apoptosis induction of spermatozoa. These effects may explain the negative direct impact of C. trachomatis infection on sperm fertilizing ability. 相似文献
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Sellami R Gharbi F Rejeb S Rejeb MN Henchi B Echevarria G Morel JL 《International journal of phytoremediation》2012,14(6):609-620
A pot experiment was conducted to investigate the effect of nickel concentration on physiological characteristics of Alyssum murale when grown in a soil mixed with sewage sludge (at the rate of 2.8%). Two types of sludge were used: agricultural sewage sludge (S1) and industrial sewage sludge with an increasing nickel concentration (S2, S3, and S4). Results showed that Ni in shoots was higher than Ni in roots. A. murale is able to concentrate up to 12730 mg/kg Ni in leaves. The highest dry matter yield was observed with plants grown with agricultural sewage sludge. An addition of S2 and S3 increased shoot biomass. However, application of S4 reduced 40% shoot dry weight as compared to the control Ni treatment did not affect all chlorophyll fluorescence parameters. The F(v)/F(m) ratio was stable between Ni treatments. Photosynthesis rate (A) increased with agricultural sewage sludge, but remained stable with variable Ni rates from the industrial sludge. The chlorophyll content increased with S1, S2 and S3 but it remains constant with S4 when compared to the control Therefore, high nickel concentration did not affect the function of the photosynthetic machine of A. murale. 相似文献
77.
Jiangtian Chen Wencke Reiher Christiane Hermann-Luibl Azza Sellami Paola Cognigni Shu Kondo Charlotte Helfrich-F?rster Jan A. Veenstra Christian Wegener 《PLoS genetics》2016,12(9)
Feeding and sleep are fundamental behaviours with significant interconnections and cross-modulations. The circadian system and peptidergic signals are important components of this modulation, but still little is known about the mechanisms and networks by which they interact to regulate feeding and sleep. We show that specific thermogenetic activation of peptidergic Allatostatin A (AstA)-expressing PLP neurons and enteroendocrine cells reduces feeding and promotes sleep in the fruit fly Drosophila. The effects of AstA cell activation are mediated by AstA peptides with receptors homolog to galanin receptors subserving similar and apparently conserved functions in vertebrates. We further identify the PLP neurons as a downstream target of the neuropeptide pigment-dispersing factor (PDF), an output factor of the circadian clock. PLP neurons are contacted by PDF-expressing clock neurons, and express a functional PDF receptor demonstrated by cAMP imaging. Silencing of AstA signalling and continuous input to AstA cells by tethered PDF changes the sleep/activity ratio in opposite directions but does not affect rhythmicity. Taken together, our results suggest that pleiotropic AstA signalling by a distinct neuronal and enteroendocrine AstA cell subset adapts the fly to a digestive energy-saving state which can be modulated by PDF. 相似文献
78.
Achour I Cavelier P Tichit M Bouchier C Lafaye P Rougeon F 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(3):2001-2009
In addition to producing conventional tetrameric IgGs, camelids have the particularity of producing a functional homodimeric IgG type lacking L (light) chains and only made up of two H (heavy) chains. This nonconventional IgG type is characterized by variable and constant regions referred to as V(H)H and C(H)H, respectively, and which differ from conventional V(H) and C(H) counterparts. Although the structural properties of homodimeric IgGs have been well investigated, the genetic bases involved in their generation are still largely unknown. In this study, we characterized the organization of genes coding for the H chains of tetrameric and homodimeric IgGs by constructing an alpaca (Lama pacos) genomic cosmid library. We showed that a single IgH locus in alpaca chromosome 4 contains all of the genetic elements required for the generation of the two types of Igs. The alpaca IgH locus is composed of a V region that contains both V(H)H and V(H) genes followed by a unique D(H)-J(H) cluster and C region genes, which include both C(H)H and C(H) genes. Although this general gene organization greatly resembles that of other typical mammalian V(n)-D(n)-J(n)-C(n) translocon IgH loci, the intermixed gene organization within the alpaca V and C regions reveals a new type of translocon IgH locus. Furthermore, analyses of cDNA coding for the membrane forms of IgG and IgM present in alpaca peripheral blood B cells are most consistent with the notion that the development of a B cell bearing homodimeric IgG passes through an IgM(+) stage, similar to the case for conventional IgG. 相似文献
79.
S.?Neji F.?Makni F.?Cheikhrouhou H.?Sellami S.?Boudaya H.?Turki A.?AyadiEmail author 《Mycopathologia》2010,170(5):353-355
This is a first case of Trichophyton soudanense isolated from Ivoiran student in Tunisia. A 24-year-old man was addressed for extensive erythematous, scaling lesions. Examination
disclosed tinea capitis, tinea corporis, tinea pedis, and onychomycosis of toenails and fingernails. Isolates were identified
as Trichophyton soudanense on the basis of macroscopy and microscopy colony characteristics. The patient was treated with fluconazole, topical econazole,
and ciclopiroxolamine varnish. Although T. soudanense was identified since the late 1950s outside the African continent especially in the North America, Brazil, Australia, and
many European countries, this is the first case reported in Tunisia. Accessibility to our universities for African students
makes possible the emergence of this dermatophyte. 相似文献
80.
Siala M Jaulhac B Gdoura R Sibilia J Fourati H Younes M Baklouti S Bargaoui N Sellami S Znazen A Barthel C Collin E Hammami A Sghir A 《Arthritis research & therapy》2008,10(2):R40-14