Antimicrobial and antioxidant activities of Streptomyces species from soils of three different cold sites in the Fez-Meknes region Morocco

The increasing demand for new bioactive compounds to combat the evolution of multi-drug resistance (MDR) requires research on microorganisms in different environments in order to identify new potent molecules. In this study, initial screening regarding the antimicrobial activity of 44 Actinomycetes isolates isolated from three soil samples from three different extremely cold sites in Morocco was carried out. Primary and secondary screening were performed against Candida albicans ATCC 60,193, Escherichia coli ATCC 25,922, Staphylococcus aureus ATCC 25,923, Bacillus cereus ATCC 14,579, other clinical MDR bacteria, and thirteen phytopathogenic fungi. Based on the results obtained, 11 active isolates were selected for further study. The 11microbial isolates were identified based on morphological and biochemical characters and their molecular identification was performed using 16S rRNA sequence homology. The UV-visible analysis of dichloromethane extracts of the five Streptomyces sp. Strains that showed high antimicrobial and antioxidant (ABTS 35.8% and DPPH 25.6%) activities revealed the absence of polyene molecules. GC-MS analysis of the dichloromethane extract of E23-4 as the most active strain revealed the presence of 21 volatile compounds including Pyrrolopyrazine (98%) and Benzeneacetic acid (90%). In conclusion, we studied the isolation of new Streptomyces strains to produce new compounds with antimicrobial and antioxidant activities in a cold and microbiologically unexplored region of Morocco. Furthermore, this study has demonstrated a significant (P < 0.0001) positive correlation between total phenolic and flavonoid contents and antioxidant capacity, paving the way for the further characterization of these Streptomyces sp. isolates for their optimal use for anticancer, antioxidant, and antimicrobial purposes.

Genetic variability in E6 and E7 oncogenes of human papillomavirus Type 16 from Congolese cervical cancer isolates

Background

The molecular epidemiological studies showed that some variants of HPV-16, distributed geographically, would present a higher risk of causing cervical cancer. This study aimed to analyze nucleotide changes of HPV-16 E6 and E7 genomic regions from infected Southwestern Congolese women.

Methods

DNA of twenty HPV-16 isolates was analyzed by amplifying the E6 and E7 genes using type-specific primers PCR and direct sequencing. The sequences obtained were aligned with the HPV-16 GenBank reference sequences.

Results

Thirteen (65.0%) out of 20 DNA-samples were successfully amplified. Genetic analysis revealed 18 and 4 nucleotide changes in E6 and E7 genomic regions respectively. The most frequently observed nucleotide variations were the missense C143G, G145T and C335T in E6 (100%), leading to the non-synonymous amino acid variation Q14D and H78Y. E7 genomic region was found to be highly conserved with two most common T789C and T795G (100%) silent variations. All HPV-16 variants identified belonged to the African lineage: 7 (53.8%) belonged to Af-1 lineage and 6 (46.1%) to Af-2 lineage. The missense mutation G622A (D21N) in the E7 region seems to be described for the first time in this study.

Conclusion

This study reported for the first time the distribution of HPV-16 E6 and E7 genetic variants in infected women from southwest Congo. The findings confirmed almost ascendancy of the African lineage in our study population.

Human papillomavirus genotypes distribution by cervical cytologic status among women attending the General Hospital of Loandjili, Pointe-Noire, Southwest Congo (Brazzaville)

HPV infection is associated with cervical cancer, one of the major public health problems in developing countries. In the Republic of Congo, despite of the high age-standardized incidence rate estimated at 25.2 per 100,000 women, molecular epidemiology data on HPV infections are very limited. We investigated HPV genotypes distribution in cervical smears among patients attending the General Hospital of Loandjili, Southwest Congo. A cross-sectional hospital-based study was conducted on 321 women. Liquid-based cytology samples were collected for cytological diagnosis and HPV detection. Nested-PCR was performed using MY09/MY11 and GP5+/GP6+ primers with genotyping by direct sequencing. Type-specific PCR for HPV-6, -11, -16, -18, -31 and -33 was also used to assess multiple infections. Out of 321 women examined, 189 (58.8%) had normal cytology, 16 (5.0%) had ASCUS and 116 (36.1%) had cytological abnormalities. HPV-DNA was detected in 22 (11.6%), 6 (37.5%), and 104 (89.6%) normal cytology, ASCUS and cytological abnormalities respectively. HPV16 was the most prevalent genotype regardless of cytological status followed by HPV70 in women without lesions and HPV33 among those with lesions. HR-HPV prevalence varied significantly according to the cervical cytology (P = 0.000). Among women without lesions, two peaks of HPV infections were observed in age group less than 30 years (60.0%) and in age group 50-59 years (7.1%). Age, age of first sex, multiple sexual partners and pregnancies were the risk factors for HPV infection in women without lesions. Our findings could be used as evidence data base for future epidemiological monitoring in this region.

Specific genotypes of human papillomavirus in 125 high-grade squamous lesions and invasive cervical cancer cases from Congolese women

BACKGROUND

Knowledge on HPV prevalence and genotype distribution in HSIL and ICC is highly essential for the introduction of an effective vaccination program and appropriate epidemiological monitoring of viral ecology before and after vaccination in Congo. This study aimed to determine the specific-HPV genotypes in HSIL and ICC among women in southwestern Congo.

METHODS

125 archival paraffin-embedded biopsy collected between 2008 and 2012 and histologically diagnosed were investigated. DNA extraction was performed using the phenol/chloroform method. HPV search was performed by nested-PCR using MY09/MY11 and GP5+/GP6+ consensus primers followed by direct sequencing.

RESULTS

The mean age of participants was 44.3 ± 8.2 years. Overall, HPV prevalence was 89.6% (112/125) with all high-risk genotypes. HPV-DNA was detected in 81.5% (53/65) of HSIL and 98.3% (59/60) of ICC. HPV 16 the most common genotype was detected in 47.1% (25/53) of HSIL and 52.5% (31/59) of ICC. Other types identified were: HPV 33 (22.6%), HPV 18 (15%), HPV 31 (11.3%) and HPV 69 (3.7%) in HSIL, and HPV 33 (28.8%), HPV 18 (11.8%), HPV 31 (5%) and HPV 35 (1.7%) in ICC. Knowing that the ADC accounted for 6.7% (4/60) of ICC cases, HPV 18 was identified in 25% (1/4) of these cases against 75% (3/4) for HPV 16.

CONCLUSION

Our study showed that HPV 16, 33, 18 and 31 were the four most common genotypes in women with HSIL and ICC. These findings indicate that current vaccines against HPV could help to reduce the burden of cervical cancer in Congo.