Acta Crystallographica Section C Crystal Structure Communications, 1986
S ,S S)- 2-Amino-4-( S-methylsulfonimido yl)- butanoic acid, CsH12N2OaS, Mr= 180"2, orthorho... more S ,S S)- 2-Amino-4-( S-methylsulfonimido yl)- butanoic acid, CsH12N2OaS, Mr= 180"2, orthorhom- bic, P212121, a=5.3472 (4), b=9.3990(8), c =16.155(1)A, u=811.9(2)A 3, z=4, Ox= 1.47 gcm -3, D,n not measured, A. = 1.5418 A, /~(Cu Ka) = 32.3 cm -~, F(000) = 384, R = 0.028 and wR =0.037 for 1494 observed data. The absolute structure reveals the (2S,SS) configuration. In the crystal lattice, the packing is maintained by hydrogen bonds. Redissolved crystals exhibit toxicity towards mice and Bacillus subtilis. Introduction. Methionine sulfoximine was found for the first time in 'agenised' flour (Mellanby, 1946; Bentley, McDermott, Moran, Pace & Whitehead, 1950). It was shown to be formed by the action of nitrogen trichloride (an improving agent for flour) on wheat proteins. It
Mutations affecting quantitatively the production of the sporulation-associated extracellular alk... more Mutations affecting quantitatively the production of the sporulation-associated extracellular alkaline protease were isolated and characterized. They fall into at least five genes, three of which, ScoA, B and C, were mapped in the argC-metC region. The pleiotropic effects of these mutations concern several or all of the following: rate and timing of protease production, synthesis of alkaline phosphatase, time-course of spore formation. Electron microscopic evidence indicates delayed switch from one morphological stage to another. The nature of the Sco mutations and the genetic regulation of sporulation are discussed.
World journal of biological and pharmaceutical research, Jun 30, 2022
The present work aims to study the chemical composition and the antimicrobial and toxicological p... more The present work aims to study the chemical composition and the antimicrobial and toxicological properties of the essential oils (EOs) of Apodocephala pauciflora leaves (LEO) and stem bark (BEO). LEO and BEO were extracted from fresh material by hydrodistillation with a yield of 0.1%. They are light, light yellow, strong smelling and dextrorotatory. Gas chromatography/mass spectrometry (GC/MS) analysis identified 42 components in LEO and 38 in BEO representing 97.54% and 99.44% of the overall composition respectively. In LEO, the major components were α-pinene (27.5%), sabinene (13.62%) and β-pinene (12.0%) and in BEO, α-pinene (34.32%), myrcene (15.1%), sabinene (14.53%). Main components such β-pinene, phellandrene and limonene were common to LEO and BEO but at different rates. However, some components were not common to both EOs: for example, cubenol (5.07%) in LEO was absent in BEO and vice versa humulene (3.91%) in BEO was absent in LEO. Both EOs were effective against all microorganisms tested, including Gram (+) and Gram (-) bacteria and a fungus, with a strain-dependent intensity. BEO was more efficient than LEO. Streptococcus pneumoniae, Pseudomonas aeruginosa, Vibrio fischeri and Candida albicans were the most susceptible. LEO was bacteriostatic against Clostridium perfringens and Candida albicans but bactericidal against the other germs tested, whereas BEO was bactericidal against all germs. With LD50 of 2.48 and 2.34 g/kg body weight, LEO and BEO were slightly toxic to mice by oral route. LEO and BEO could be used as alternatives to synthetic antibiotics against several pathogenic microorganisms.
Medecine tropicale et sante internationale, Jun 30, 2022
Background: Malaria is a parasitic disease caused by a hematozoan of the genus Plasmodium. Early ... more Background: Malaria is a parasitic disease caused by a hematozoan of the genus Plasmodium. Early diagnosis followed by effective treatment is one of the keys to control this disease. In Madagascar, after more than 60 years of use for the treatment of uncomplicated malaria, chloroquine (CQ) was abandoned in favor of artesunate + amodiaquine (ASAQ) combination because of high prevalence of CQ treatment failure. Surveillance based on the assessment of therapeutic efficacy and genetic markers of resistance to antimalarials is therefore essential in order to detect the emergence of potentially resistant parasites as early as possible. In this context, our study aimed to genotype the Plasmodium falciparum chloroquine resistance transporter gene or Pfcrt and Plasmodium falciparum multidrug resistance gene 1 or Pfmdr1 in isolates collected from children in the district of Vatomandry. Methods: A total of 142 P. falciparum isolates collected during active case detection of malaria in children under 15 years old, between February and March of 2016 and 2017 in Vatomandry district, were analyzed. Pfcrt (K76T codon) and Pfmdr1 (N86Y codon) genotyping was carried out by polymerase chain reaction followed by enzymatic digestion (restriction fragment length polymorphism) or PCR-RFLP. Results: The successful rates of amplification of Pfcrt and Pfmdr1 genes were low, around 27% and 39% respectively. The prevalence of isolates carrying the mutant Pfcrt K76T codon and the mutant Pfmdr1 N86Y codon was 2.6% [95% confidence interval (95% CI): 0.1 - 15.0%] and 36% [95% CI: 23.7 - 49.7%] respectively. Conclusion: Despite the limited number of samples analyzed, our study highlighted the circulation of isolates carrying both the mutant Pfcrt K76T and Pfmdr1 N86Y alleles. Although the prevalence of mutations in Pfcrt and Pfmdr1 genes that we observed was low, other studies should be carried out in order to follow the evolution of these markers in time and space. The use of more sensitive methods will better characterize P. falciparum strains circulating in Madagascar. Artesunate-amodiaquine is used as a first-line treatment for uncomplicated malaria in the country; it is also crucial to monitor the other codons, i.e. 184 and 1246 of the Pfmdr1 gene, implicated in the resistance of P. falciparum to amodiaquine in Africa.
Acta Crystallographica Section C Crystal Structure Communications, 1986
S ,S S)- 2-Amino-4-( S-methylsulfonimido yl)- butanoic acid, CsH12N2OaS, Mr= 180"2, orthorho... more S ,S S)- 2-Amino-4-( S-methylsulfonimido yl)- butanoic acid, CsH12N2OaS, Mr= 180"2, orthorhom- bic, P212121, a=5.3472 (4), b=9.3990(8), c =16.155(1)A, u=811.9(2)A 3, z=4, Ox= 1.47 gcm -3, D,n not measured, A. = 1.5418 A, /~(Cu Ka) = 32.3 cm -~, F(000) = 384, R = 0.028 and wR =0.037 for 1494 observed data. The absolute structure reveals the (2S,SS) configuration. In the crystal lattice, the packing is maintained by hydrogen bonds. Redissolved crystals exhibit toxicity towards mice and Bacillus subtilis. Introduction. Methionine sulfoximine was found for the first time in 'agenised' flour (Mellanby, 1946; Bentley, McDermott, Moran, Pace & Whitehead, 1950). It was shown to be formed by the action of nitrogen trichloride (an improving agent for flour) on wheat proteins. It
Mutations affecting quantitatively the production of the sporulation-associated extracellular alk... more Mutations affecting quantitatively the production of the sporulation-associated extracellular alkaline protease were isolated and characterized. They fall into at least five genes, three of which, ScoA, B and C, were mapped in the argC-metC region. The pleiotropic effects of these mutations concern several or all of the following: rate and timing of protease production, synthesis of alkaline phosphatase, time-course of spore formation. Electron microscopic evidence indicates delayed switch from one morphological stage to another. The nature of the Sco mutations and the genetic regulation of sporulation are discussed.
World journal of biological and pharmaceutical research, Jun 30, 2022
The present work aims to study the chemical composition and the antimicrobial and toxicological p... more The present work aims to study the chemical composition and the antimicrobial and toxicological properties of the essential oils (EOs) of Apodocephala pauciflora leaves (LEO) and stem bark (BEO). LEO and BEO were extracted from fresh material by hydrodistillation with a yield of 0.1%. They are light, light yellow, strong smelling and dextrorotatory. Gas chromatography/mass spectrometry (GC/MS) analysis identified 42 components in LEO and 38 in BEO representing 97.54% and 99.44% of the overall composition respectively. In LEO, the major components were α-pinene (27.5%), sabinene (13.62%) and β-pinene (12.0%) and in BEO, α-pinene (34.32%), myrcene (15.1%), sabinene (14.53%). Main components such β-pinene, phellandrene and limonene were common to LEO and BEO but at different rates. However, some components were not common to both EOs: for example, cubenol (5.07%) in LEO was absent in BEO and vice versa humulene (3.91%) in BEO was absent in LEO. Both EOs were effective against all microorganisms tested, including Gram (+) and Gram (-) bacteria and a fungus, with a strain-dependent intensity. BEO was more efficient than LEO. Streptococcus pneumoniae, Pseudomonas aeruginosa, Vibrio fischeri and Candida albicans were the most susceptible. LEO was bacteriostatic against Clostridium perfringens and Candida albicans but bactericidal against the other germs tested, whereas BEO was bactericidal against all germs. With LD50 of 2.48 and 2.34 g/kg body weight, LEO and BEO were slightly toxic to mice by oral route. LEO and BEO could be used as alternatives to synthetic antibiotics against several pathogenic microorganisms.
Medecine tropicale et sante internationale, Jun 30, 2022
Background: Malaria is a parasitic disease caused by a hematozoan of the genus Plasmodium. Early ... more Background: Malaria is a parasitic disease caused by a hematozoan of the genus Plasmodium. Early diagnosis followed by effective treatment is one of the keys to control this disease. In Madagascar, after more than 60 years of use for the treatment of uncomplicated malaria, chloroquine (CQ) was abandoned in favor of artesunate + amodiaquine (ASAQ) combination because of high prevalence of CQ treatment failure. Surveillance based on the assessment of therapeutic efficacy and genetic markers of resistance to antimalarials is therefore essential in order to detect the emergence of potentially resistant parasites as early as possible. In this context, our study aimed to genotype the Plasmodium falciparum chloroquine resistance transporter gene or Pfcrt and Plasmodium falciparum multidrug resistance gene 1 or Pfmdr1 in isolates collected from children in the district of Vatomandry. Methods: A total of 142 P. falciparum isolates collected during active case detection of malaria in children under 15 years old, between February and March of 2016 and 2017 in Vatomandry district, were analyzed. Pfcrt (K76T codon) and Pfmdr1 (N86Y codon) genotyping was carried out by polymerase chain reaction followed by enzymatic digestion (restriction fragment length polymorphism) or PCR-RFLP. Results: The successful rates of amplification of Pfcrt and Pfmdr1 genes were low, around 27% and 39% respectively. The prevalence of isolates carrying the mutant Pfcrt K76T codon and the mutant Pfmdr1 N86Y codon was 2.6% [95% confidence interval (95% CI): 0.1 - 15.0%] and 36% [95% CI: 23.7 - 49.7%] respectively. Conclusion: Despite the limited number of samples analyzed, our study highlighted the circulation of isolates carrying both the mutant Pfcrt K76T and Pfmdr1 N86Y alleles. Although the prevalence of mutations in Pfcrt and Pfmdr1 genes that we observed was low, other studies should be carried out in order to follow the evolution of these markers in time and space. The use of more sensitive methods will better characterize P. falciparum strains circulating in Madagascar. Artesunate-amodiaquine is used as a first-line treatment for uncomplicated malaria in the country; it is also crucial to monitor the other codons, i.e. 184 and 1246 of the Pfmdr1 gene, implicated in the resistance of P. falciparum to amodiaquine in Africa.
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