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101.
Hacne Medkour Inestin Amona Jean Akiana Younes Laidoudi Bernard Davoust Idir Bitam Ismail Lafri Anthony Levasseur Georges Diatta Cheikh Sokhna R. Adriana Hernandez-Aguilar Amanda Barciela Slim Gorsane Henri Banga-Mboko Didier Raoult Florence Fenollar Oleg Mediannikov 《The Yale journal of biology and medicine》2021,94(2):227
The close phylogenetic relationship between humans and other primates creates exceptionally high potential for pathogen exchange. The surveillance of pathogens in primates plays an important role in anticipating possible outbreaks. In this study, we conducted a molecular investigation of pathogenic bacteria in feces from African nonhuman primates (NHPs). We also investigated the pathogens shared by the human population and gorillas living in the same territory in the Republic of Congo. In total, 93% of NHPs (n=176) and 95% (n=38) of humans were found to carry at least one bacterium. Non-pallidum Treponema spp. (including T. succinifaciens, T. berlinense, and several potential new species) were recovered from stools of 70% of great apes, 88% of monkeys, and 79% of humans. Non-tuberculosis Mycobacterium spp. were also common in almost all NHP species as well as in humans. In addition, Acinetobacter spp., members of the primate gut microbiota, were mainly prevalent in human and gorilla. Pathogenic Leptospira spp. were highly present in humans (82%) and gorillas (66%) stool samples in Congo, but were absent in the other NHPs, therefore suggesting a possible gorillas-humans exchange. Particular attention will be necessary for enteropathogenic bacteria detected in humans such as Helicobacter pylori, Salmonella spp. (including S. typhi/paratyphi), Staphyloccocus aureus, and Tropheryma whipplei, some of which were also present in gorillas in the same territory (S. aureus and T. whipplei). This study enhances our knowledge of pathogenic bacteria that threaten African NHPs and humans by using a non-invasive sampling technique. Contact between humans and NHPs results in an exchange of pathogens. Ongoing surveillance, prevention, and treatment strategies alone will limit the spread of these infectious agents. 相似文献
102.
103.
Bekkali Y Thomson DS Betageri R Emmanuel MJ Hao MH Hickey E Liu W Patel U Ward YD Young ER Nelson R Kukulka A Brown ML Crane K White D Freeman DM Labadia ME Wildeson J Spero DM 《Bioorganic & medicinal chemistry letters》2007,17(9):2465-2469
The synthesis and in vitro activities of a series of succinyl-nitrile-based inhibitors of Cathepsin S are described. Several members of this class show nanomolar inhibition of the target enzyme as well as cellular potency. The inhibitors displaying the greatest potency contain N-alkyl substituted piperidine and pyrrolidine rings spiro-fused to the alpha-carbon of the P1 residue. 相似文献
104.
Mohammadi Shiva Mostafavi-Pour Zohreh Ghasemi Younes Barazesh Mahdi Kavousi Pour Soudabeh Atapour Amir Mokarram Pooneh Morowvat Mohammad Hossein 《International journal of peptide research and therapeutics》2019,25(4):1279-1290
International Journal of Peptide Research and Therapeutics - Escherichia coli is one of the simplest hosts which is widely being used to express heterologous proteins. However, without appropriate... 相似文献
105.
Younes Jahangiri-Noudeh Samaneh Akbarpour Mojtaba Lotfaliany Neda Zafari Davood Khalili Maryam Tohidi Mohammad Ali Mansournia Fereidoun Azizi Farzad Hadaegh 《PloS one》2014,9(12)
Aims/Hypothesis
To investigate secular trends in cardiovascular disease (CVD) risk factors during a decade of follow-up in a Middle Eastern cohort, and to compare observed trends between diabetic and non-diabetic populations.Methods
In a population of 6181 participants (2622 males and 3559 females), diabetes status and CVD risk factors were evaluated in 4 study phases from 1999–2011. 1045 subjects had type 2 diabetes mellitus at baseline and 5136 participants were diabetes-free. To examine the trends of CVD risk factors, generalized estimation equation models were constructed. The interaction between the diabetes status and each phase of the study was checked in a separate model.Results
During the follow-up period diabetic females significantly gained better control of their blood pressure, serum low density lipoprotein cholesterol and general and central obesity measures compared to non-diabetic counterparts, although 60% of them had high BP and 64% had high serum LDL-C levels till the end of the study. Diabetic males however, experienced significantly better control on their serum LDL-C and general and central obesity measures compared to their non-diabetic controls; but 24% of them were still smoker, 63% had high BP and 60% had high serum LDL-C levels at the end of the follow-up (all Ps interaction <0.05). Use of lipid-lowering and antihypertensive medications increased consistently in both diabetic and non-diabetic populations.Conclusions/Interpretation
Although CVD risk factors have been controlled to some extent among diabetic population in Iran, still high numbers of people with diabetes have uncontrolled CVD risk factors that prompt more attention. 相似文献106.
Sérgio P. A. Osorio Victor A. Garcia Rivera Luiz Antonio O. Nunes Euclydes Marega Danilo Manzani Younes Messaddeq 《Plasmonics (Norwell, Mass.)》2012,7(1):53-58
In this paper, we report on luminescence and absorbance effects of Er+3:Au-doped tellurite glasses synthesized by a melting-quenching and heat treatment technique. After annealing times of 2.5,
5.0, 7.5, and 10.0 h, at 300 °C, the gold nanoparticles (GNP) effects on the Er+3 are verified from luminescence spectra and the corresponding levels lifetime. The localized surface plasmon resonance around
800 nm produced a maximum fluorescence enhancement for the band ranging from 800 to 840 nm, corresponding to the transitions
4H11/2 → 4I13/2 (805 nm) and 4S3/2 → 4I13/2 (840 nm), with annealing time till 7.5 h. The measured lifetime of the levels 4H11/2 and 4S3/2 confirmed the lifetime reduction due to the energy transfer from the GNP to Er+3, causing an enhanced photon emission rate in these levels. 相似文献
107.
Younes M Loewen AH Ostrowski M Laprairie J Maturino F Hanly PJ 《Journal of applied physiology (Bethesda, Md. : 1985)》2012,112(2):249-258
It is generally believed that reflex recruitment of pharyngeal dilator muscles is insufficient to open the airway of obstructive apnea (OSA) patients once it is closed and, therefore, that arousal is required. Yet arousal promotes recurrence of obstruction. There is no information about how much dilator [genioglossus (GG)] activation is required to open the airway (GG Opening Threshold) or about the capacity of reflex mechanisms to increase dilator activity before/without arousal (Non-Arousal Activation). The relationship between these two variables is important for ventilatory stability. We measured both variables in 32 OSA patients (apnea-hypopnea index 74 ± 42 events/h). GG activity was monitored while patients were on optimal continuous positive airway pressure (CPAP). Zopiclone was administered to delay arousal. Maximum GG activity (GG(MAX)) and airway closing pressure (P(CRIT)) were measured. During stable sleep CPAP was decreased to 1 cmH(2)O to induce obstructive events and the dial-downs were maintained until the airway opened with or without arousal. GG activity at the instant of opening (GG Opening Threshold) was measured. GG Opening Threshold averaged only 10.4 ± 9.5% GG(Max) and did not correlate with P(CRIT) (r = 0.04). Twenty-six patients had >3 openings without arousal, indicating that Non-Arousal Activation can exceed GG Opening Threshold in the majority of patients. GG activity reached before arousal in Arousal-Associated Openings was only 5.4 ± 4.6% GG(MAX) below GG Opening Threshold. We conclude that in most patients GG activity required to open the airway is modest and can be reached by non-arousal mechanisms. Arousals occur in most cases just before non-arousal mechanisms manage to increase activity above GG Opening Threshold. Measures to reduce GG Opening Threshold even slightly may help stabilize breathing in many patients. 相似文献
108.
Suffredini IB Paciencia ML Nepomuceno DC Younes RN Varella AD 《Memórias do Instituto Oswaldo Cruz》2006,101(3):287-290
Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 microg/ml and minimal bactericidal concentration (MBC) = 90 microg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 microg/ml and MBC = 270 microg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay. 相似文献
109.
Rolland A Boquet I Norreel JC Moret V Laras Y Kraus JL 《Bioorganic & medicinal chemistry letters》2008,18(1):169-174
Using SVZ (subventricular zone) tissue explants from one-day-old mice, we investigated the activity of new amino aromatic disulfide analogues and polyazamacrocycles on the migration of SVZ cells (neuroblasts). We found that among the tested analogues, non-peptidic disulfide derivative 8 significantly decreases the migration of neuroblasts from SVZ cells, and antagonized the stimulating activity of disulfide cyclic peptide 1. Discovery of compounds 1 and 8 constitutes new chemical tools which could be used to understand the mechanism of neuroblast migration during neurogenesis and eventually to identify specific genes involved in the neurogenesis. 相似文献
110.
Kemel Jellouli Ali Bougatef Laila Manni Rym Agrebi Rayda Siala Islem Younes Moncef Nasri 《Journal of industrial microbiology & biotechnology》2009,36(7):939-948
A protease-producing bacterium was isolated from an alkaline wastewater of the soap industry and identified as Vibrio metschnikovii J1 on the basis of the 16S rRNA gene sequencing and biochemical properties. The strain was found to over-produce proteases
when it was grown at 30°C in media containing casein as carbon source (14,000 U ml−1). J1 enzyme, the major protease produced by V. metschnikovii J1, was purified by a three-step procedure, with a 2.1-fold increase in specific activity and 33.3% recovery. The molecular
weight of the purified protease was estimated to be 30 kDa by SDS-PAGE and gel filtration. The N-terminal amino acid sequence
of the first 20 amino acids of the purified J1 protease was AQQTPYGIRMVQADQLSDVY. The enzyme was highly active over a wide
range of pH from 9.0 to 12.0, with an optimum at pH 11.0. The optimum temperature for the purified enzyme was 60°C. The activity
of the enzyme was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine protease. The kinetic
constants K
m and K
cat of the purified enzyme using N-succinyl-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide were 0.158 mM and 1.14 × 105 min−1, respectively. The catalytic efficiency (K
cat
/K
m) was 7.23 × 108 min−1 M−1. The enzyme showed extreme stability toward non-ionic surfactants and oxidizing agents. In addition, it showed high stability
and compatibility with some commercial liquid and solid detergents. The aprJ1 gene, which encodes the alkaline protease from V. metschnikovii J1, was isolated, and its DNA sequence was determined. The deduced amino acid sequence of the preproenzyme differs from that
of V. metschnikovii RH530 detergent-stable protease by 12 amino acids, 7 located in the propeptide and 5 in the mature enzyme. 相似文献