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Baba-Moussa, L.

Publications and source records attributed to Baba-Moussa, L..

4 recordsLinked to original sources

Isolation and characterization of novel Klebsiella phages from Benin and their antibiofilm activities on multidrug resistant and hypervirulent strains of Klebsiella pneumoniae

Hypervirulent Klebsiella pneumoniae represents a growing clinical threat, particularly where multidrug resistance limits treatment options. Here, we report the isolation and characterization of three novel lytic phages from Benin (Kp1Bj_HH11_M23, Kp2Bj_LN294_M23, and Kp10Bj_LN54_14). These Myoviruses, belonging to the genera Marfavirus and Jiaodavirus, display broad host range activity against multidrug-resistant and hypervirulent K. pneumoniae strains. Genomic analysis confirmed the absence of virulence and antimicrobial resistance genes. The phages exhibit rapid adsorption, short latency periods, and high burst sizes (119-2208 PFU/cell). All three phages significantly inhibited biofilm formation and reduced established biofilms in vitro. Their stability across a wide range of temperatures and pH further supports their potential for therapeutic development. Together, these data highlight the value of locally sourced phages as candidates for tackling region-specific antimicrobial resistance challenges.

microbiology↗

Serotypes of Dengue Virus and Kdr Mutations F1534C, S989P, V410L, V1016I, and V1016G in Aedes aegypti and Aedes albopictus Mosquitoes from the commune of AbomeyCalavi, Southern Benin

Dengue is a viral infection transmitted by mosquitoes of the Aedes genus, responsible for millions of cases each year. In Benin, several outbreaks have been reported, particularly in Abomey-Calavi, where the first dengue-related death was recorded in 2019. In the absence of a specific treatment, vector control remains the primary preventive measure. However, the emergence of insecticide resistance, notably through kdr mutations, could compromise its effectiveness. This study aims to identify the dengue virus serotypes circulating in the commune of Abomey-Calavi and to assess the frequency of kdr mutations V410L, V1016G, V1016I, F1534C, and S989P in Aedes aegypti and Aedes albopictus mosquitoes. Mosquitoes were collected in August 2024 from four arrondissement Togba, Calavi, Akassato, and Godomey through morning and afternoon spraying. After morphological identification, molecular analyses were conducted to detect the viral serotypes and kdr mutations. A total of 218 Aedes mosquitoes were collected, with a predominance of Aedes aegypti (68.8%) compared to Aedes albopictus (31.2%). The overall dengue positivity rate was 23.39% (95% CI: 17.9 - 29.6). The most frequent serotype was DENV-3 (12.4%), followed by DENV-2 (6.9%), DENV-1 (5%), and DENV-4 (0.09%). Six mosquitoes were co-infected with two serotypes, including three with DENV-1 and DENV-4. kdr mutations were detected in both species, with frequencies of 45% for V1016G, 44% for S989P, 40% for F1534C, 22% for V410L, and 19% for V1016I. Four mosquitoes carried three simultaneous mutations, while twenty-two carried two. Two mosquitoes co-infected with two serotypes also carried two different mutations. These results highlight the active circulation of the dengue virus and the presence of kdr mutations in Aedes mosquitoes in Abomey-Calavi. However, no significant association was observed between dengue infection and kdr mutations, and their distribution was independent of the viral serotype. These findings emphasize the need for regular monitoring of kdr mutations to adapt vector control strategies and limit the spread of dengue.

biochemistry↗

Unlocking the potential of Uvaria chamae: A cream formulation for combatting Staphylococcus aureus skin infections

Staphylococcus aureus (S. aureus) skin infections remain a prevalent public health concern worldwide, posing ongoing challenges in treatment. Uvaria chamae roots has demonstrated significant effectiveness against S. aureus. This study aimed to propose a dermal formulation based on Uvaria chamae for treating bacterial skin infections. The antibacterial activity was first confirmed. Tests including the time-kill test, the erythromycin outer membrane permeability test, and the ATPase/H+ proton pump inhibition test were conducted to explore the antibacterial mode of action. A cream was prepared using the phase inversion technique and subjected to quality control and senso-rheological testing. The cream was tested for antibacterial activity and skin toxicity (OECD guideline 404). The in vivo antibacterial effect and wound-healing potential of the Uvaria chamae cream were then assessed on Wistar rat. The ethanolic extract of Uvaria chamae root exhibited bactericidal effects on the tested S. aureus strains. In combination with erythromycin, the extract enhanced the permeability of S. aureuss outer membrane while inhibiting ATPase/H+ proton pumps. The pharmaceutical quality of the produced cream revealed acceptable macroscopic conditions and satisfactory homogeneity. Antibacterial activity evaluation showed significant activity at low concentrations. The creams healing properties indicated a significant decrease in wound diameter (p<0.05) over time, culminating in complete healing on day 13 for the treated group, with a retraction percentage of 99.99%. These findings support the safe use of Uvaria chamae extracts in managing S. aureus skin infections and pave the way for pre-clinical testing and potential market introduction of this cream.

microbiology↗

Anopheles bionomics, insecticide resistance mechanisms and malaria transmission in the Korhogo area, northern Cote d Ivoire: a pre-intervention study

BackgroundA better understanding of malaria transmission at a local scale is essential for developing and implementing effective control strategies. In the frame of a randomized control trial, we aimed to provide an updated description of malaria transmission in the Korhogo area, northern Cote dIvoire, and to get baseline data for the trial.\n\nMethodsWe performed Human Landing Collections in 26 villages in the Korhogo area during the rainy season (September-October 2016, April-May 2017) and the dry season (November-December 2016, February-March 2017). We used Polymerase chain reaction techniques to ascertain the species of the An. gambiae complex, Plasmodium sp sporozoite infection and insecticide resistance mechanisms in a subset of Anopheles vectors.\n\nResultsAnopheles gambiae s.l. was the predominant malaria vector in the Korhogo area. Overall, more vectors were collected outdoors than indoors (P < 0.001). Of the 774 An. gambiae s.l. tested in the laboratory, 89.65% were An. gambiae s.s. and 10.35% were An. coluzzii. The frequencies of the kdr allele were very high in An. gambiae s.s. but the ace-1 allele was found at moderate frequencies. An unprotected individual living in the Korhogo area received an average of 9.04, 0.63, 0.06 and 0.12 infected bites per night in September-October, November-December, February-March, and April-May, respectively.\n\nConclusionsThe intensity of malaria transmission is extremely high in the Korhogo area, especially during the rainy season. Malaria control in highly endemic areas such as Korhogo needs to be strengthened with complementary tools in order to reduce the burden of the disease.

zoology↗