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Introduction: Kaposi's sarcoma is endemic in sub-Saharan Africa and remains to this day the most common cancer in people living with HIV. This study aimed to obtain epidemiological data on Kaposi's sarcoma diagnosed at the cytopathological anatomy laboratory in the Republic of Congo. Material and Methods: Authors collected all cases of Kaposi's Sarcoma over a 22 years period from 2000 to 2021. Data was collected from hospital registers, medical records and reports of pathological examination results. Results: A total of 37 cases were enrolled in the study, with the annually incidence of Kaposi's sarcoma around 2 cases/year. The age of patients at diagnosis ranged from 13 to 80 years old, with the average age of 31.5 years. Male to female ratio was 3.1 and females were older than males. The majority of the lesions were in the lower limbs, 13 (35%) and nodular KS accounted the most observed elementary lesions of all cases (59%). Conclusion: Although it occurs frequently in PLHIV, KS is less common in the Republic of Congo and remains an unrecognized condition among the Congolese population. Key words: Kaposi's sarcoma, Epidemiology, Republic of Congo

Introduction: The Epstein Barr virus (EBV) is associated with a variety of human malignancies including gastric cancer (GC). Several studies have shown an association between Epstein-Barr virus (EBV) infection and the occurrence of many cancers in humans, including certain gastric carcinomas (GC). Indeed, recent studies have reported that 10% of GCs are associated with EBV. There is no study on the association of EBV with CG in Brazzaville. The aim of the study was to detect EBV DNA in gastric adenocarcinoma in Brazzaville. Materials and Methods: Samples of carcinomatous gastric tissues were analyzed by qPCR to detect EBV DNA. The samples were collected retrospectively between January 2008 and December 2018. Results: Fifty two samples were analyzed. The PCR results showed that the detection of EBV DNA on our sample was 3.8%. Conclusion: The results obtained from this preliminary study confirm the presence of EBV DNA in gastric adenocarcinoma, which is consistent with data from the literature. Key words: DNA, EBV, gastric adenocarcinoma, qPCR.

Introduction: Gastric cancer is predominantly represented by adenocarcinoma, which is the most common histological type. The latter develops from the gastric epithelium and remains a global public health problem. The aim of the study was to assess the overexpression of the Her2 biomarker of gastric adenocarcinoma in Brazzaville. Materials and Methods: Samples of gastric carcinomatous tissues (paraffin blocks) were analyzed by the manual immunohistochemistry technique for the evaluation of the Her2 biomarker. Samples were collected retrospectively between January 2008 and December 2018. Results: during this period, 52 samples were analyzed. The immunohistochemistry results show that the Her2 protein positivity rate in adenocarcinoma cases was 9.6%. Conclusion: The results obtained during this preliminary study confirm the presence of the Her2 biomarker in 9.6% of gastric adenocarcinoma cases, which is consistent with the data in the literature. Key words: Her2, Gastric adenocarcinoma, Immunohistochemistry.

Background: Numerous reviews report the beneficial effects of alpha tocopherol in preventive supplementation and also as an adjuvant in the treatment of some pathologies (cardiovascular, cancers). In this work, we analyzed the effects of vitamin E at high doses on some biochemical parameters. Methods: Thirty-two adult male and female mice (CD1 albino mice) were randomly selected for a 4-week experiment. The mice were supplemented with alpha tocopherol at doses of 150, 400 and 750mg/day. With a high dietary intake of vitamin E Results: According to our analyses, we can note Excess weight predominated in groups 4 to 7. All the blood lipid parameters showed an abnormal concentration, as of the 400 mg dose of α-T-acetate. Hyperglycemia and hyperlipidemia were observed. These variations were more pronounced for total cholesterol and triglycerides than for HDL and LDL fractions. Conclusion: The study showed significant effects of high-dose α-T supplementation on biochemical parameters, mainly hyperglycemia and dyslipidemia. Key words: Vitamin E, Alpha-tocopherol, blood biochemical parameters.

Introduction: the Epstein Barr virus is one of the very first oncogenic viruses to be identified as responsible for human malignancies. Its role as an etiological agent of breast cancer remains controversial, however, despite the growing molecular evidence. The aim of this study was detected the presence of EBV DNA in patients with breast cancer in the Republic of Congo. Methods: The study was conducted on 90 samples of formalin fixed and paraffin-embedded tissue blocks (FFPE) from breast cancer tissue. The immunohistochemistry technique was used to test for the expression of the LMP1 antibody and DNA was extracted from all blocks of formalin-fixed and paraffin-embedded breast cancer tissue (FFPE) to detect presence of EBV 1 DNA by real-time polymerase chain reaction (PCR). Results: EBV was detected in 12.33% (12/90) of formalin-fixed, paraffin-embedded (FFPE) breast cancer tissue blocks. All formalin-fixed, paraffin-embedded (FFPE) breast cancer tissue blocks with positive EBV DNA were high tumor grades (II and III). Overall EBV infection with clinicopathological features of breast cancer cases showed no significant difference (P>0.05). However, a statistically significant difference was observed between EBV infection and histological types (P=0.04). Conclusion: Our results provide evidence for the presence of EBV DNA in female breast cancer in Congo Brazzaville. However, this evidence is substantial but inconclusive for the involvement of viruses in the development of breast cancer. Therefore, future investigations will be needed to elucidate the exact role of EBV in breast cancer in women in the Republic of Congo. Key words: EBV, breast cancer, women, Congo Brazzaville.

Introduction: Breast cancer is a heterogeneous disease with a variety of morphological, molecular, treatment response and clinical outcome characteristics. The objective of this work was to assess the epidemiological, histological, immunohistochemical and molecular subtypes of breast cancer in women in the Republic of Congo. Material and Methods: We carried out a cross-sectional descriptive study which took place from January 1, 2014 to December 31, 2020. The study focused on 150 cases of breast cancer in patients diagnosed at the University Hospital of Brazzaville (CHU-B). The epidemiological, clinical, histological, immunohistochemical and molecular subtypes were the variables studied. Results: The mean age was 48.09 ± 13.87 years with the extremes of 22 years and 80 years. The study of the profession; the most represented in our study was that of the cultivator 20.67%. A predominance of breast cancer localization was observed in the left breast in 47.33%. The frequency of a family history was 7.33% or 11 cases. The most frequently represented histologic type was 62% invasive non-specific type carcinoma (CITNS). The most represented histological grade was Scarff Bloom Richardson grade II (51.33%), followed by grade III 24% and grade I in 12% of cases. Regarding the results of IHC; of the 150 cases, 102 (68%) had positive hormone receptors (HR +). The ORs were positive in 102 cases (68%) while the PRs were positive in 98 cases (65.33%). The Her2 oncogene was over expressed in 38 cases (25.3%). The Ki-67 proliferation index was known for the 150 cases, including 77 (51.33%) less than 15% and 73 (48.67%) greater than or equal to 15%. The distribution of molecular subtypes was 46% luminal A, 22% triple negative, 17% luminal B and 10% Her2 +. Tumors of unknown molecular profile were 5%. The correlation was found between molecular subtype and histological type. This result was statistically significant (p 0.05). The correlation was found between molecular subtype and histological type. This result was statistically significant (p 0.05). The correlation was found between molecular subtype and histological type. This result was statistically significant (p 0.05). Conclusion: It should be noted that the association between histological and immunohistochemical diagnosis can help determine the phenotype of breast cancer, with the aim of guiding treatment and therefore improving response to treatment. Key words: Epidemiology, Histology, Immunohistochemistry, molecular subtypes, breast cancer, Republic of Congo.

Introduction: Breast cancer is a heterogeneous disease with a variety of morphological and molecular characteristics impacting treatment response. This study aimed to evaluate by immunohistochemistry and RT-PCR the overexpression of HER2 in breast cancer in women in the Republic of Congo. Materials and Methods: We conducted an 8-month cross-sectional descriptive study. 25 paraffin biopsies of breast cancer cases in patients diagnosed at the University Hospital of Brazzaville were collected. Epidemiological, clinical, histological, immunohistochemical and molecular aspects were studied. Results: The mean age of the patients was 49.64 ± 13.20 years (31-80 years). 60% of the patients had a right localization of the tumor. 76% of the patients had an invasive nonspecific type carcinoma. The T4b N1a M0 stage was predominant, representing 56% of the study population. SBR histopronostic grade 1 was represented by 60% of patients. Estrogen and progesterone receptors were positive in the range of 45% and 60%, respectively. The HER2 oncoprotein was positive in 12% (3/25) of 25 cases for IHC. The luminal group was in the majority with 32%. Molecular analysis of the HER2 gene by RT-PCR revealed over expression in 60% (15/25) of cases, 3 of which were already positive for IHC. With the "AmoyDx® HER2 Mutation Detection Kit", 12 mutations were identified, 10 of which involved exon 20, ie 83.33% and 2 mutations with exon 19, ie 16.67% of cases. The correlation of the over expression of the HER2 gene showed a statistically significant difference between the two techniques, p

Human herpesvirus 8 (HHV8) is endemic in Africa, although studies of this infection are rare in Congo. We evaluated seroprevalence and HHV-8 diversity among people living with HIV. We included 353 patients receiving highly active antiretroviral therapy. Antibodies against HHV-8 latency-associated nuclear antigen were detected by indirect immunofluorescence. In HHV-8 positive patients, we performed HHV-8 quantification in blood and saliva by real-time PCR and typing by Sanger sequencing of K1 open reading frame. HHV-8 seroprevalence was 19%, being male (odd ratio [OR] = 1.741, [95% Confidence interval {CI}, 0.97–3.07]; p = 0.0581) and having multiple sex partners before HIV diagnosis (OR = 1.682, [CI 95%, 0.97–2.92]; p = 0.0629) tended to be associated with HHV-8 seropositivity. Of the 64 HHV-8 seropositive patients, HHV-8 DNA was detected in 10 (16%) in saliva, 6 (9%) in whole-blood and in 2 (3%) in both whole-blood and saliva. Three out of 6 HHV-8 strains were subtypes A5, 2 subtype B1 and 1 subtype C. HHV-8 seroprevalence was relatively low with more frequent carriage in men, associated with asymptomatic oral excretion and a predominance of subtype A5. These data tend to support the hypothesis of horizontal transmission in people living with HIV in Brazzaville.

Background. Since the work of Band et al. in 1990 (Proc. Natl. Acad. Sci. USA 87:463–467), several studies have suggested a possible link between the pathogenesis of breast cancer and viral infection. Infection with oncogenic HPV has been one of the viruses implicated in breast cancer cases worldwide. Objective. To investigate the presence of HPV DNA in archived paraffin-embedded breast cancer cases at the University Hospital of Brazzaville and to assess the association between viral HPV infections and clinicopathological features. Methods. A total of 40 formalin-fixed paraffin-embedded (FFPE) biopsies were retrospectively collected and available information was recorded. HPV detection and genotyping were performed by real-time PCR by GeneXpert technology (Cepheid, Sunnyvale, USA). Results. The mean age was 51.1±11.4 years (range 22–75 years; median was 47). Overall, HPV DNA was detected in six (15%) breast carcinoma samples. HPV-16, the most common genotype was identified in 83.7 % of all samples. HPV porting with clinicopathological features showed no significant difference (P>0.05). However, a statistically significant difference was observed between HPV infection and SBR grade (P=0.05). Conclusion. Our study described a high prevalence of HPV-HR in breast cancer cases in the Congolese woman. Future type case-control studies are necessary to better describe the potential role of HPV in the occurrence of breast cancer in Congo.

Background: The mature cystic ovarian teratoma (MCOT) is a common benign ovarian neoplasm in the world, most prevalent among women of childbearing age. It is a disease related to parental imprinting in which genome is exclusively maternal. The purpose of the study was to review the tumour features in Congolese patients in order to clarify its prevalence, and its histological forms and to report the eventual associated chromosomal anomalies described in literature. Methods: It was a retrospective study of MCOT seen in University Teaching Hospital of Brazzaville for a period of seven years, and five DNAs previously extracted from five MCOT. Two antibodies: DLK1 and TIMP2 were also studied by immunohistochemistry (IHC). The confirmed positive diagnosis was performed by Hematoxylin-Eosin method. The eventual presence of chromosomal anomalies was investigated by metaphasic Comparative Genomic Hybridization (mCGH) method. IHC analysis had permit to verify expression of paternal imprinted gene DLK1 expression compared to maternal imprinted gene TIMP2. Results: During the study period, a total of 215 cases of ovarian neoplasms have been seen, from which 20% (43/215 cases) with confidence interval (CI) 95% = [14.7% - 25.3%] were diagnosed MCOT. They represent 38.7% (43/111 cases) (IC 95% = [29.9% - 48.1%]) of all benign ovarian tumors and they account for 0.4% (43/10170) of all tumors diagnosed during the study period. The average age of patients having MCOT was 30.7 years with extreme ranging from 2 to 70 years. Cutaneous tissue was the most prevalent histological form. About IHC analysis, no staining was observed with mono-allelic paternal gene DLK1 contrasting with high TIMP2 staining of nuclear stem cells in the basal layer of the epidermis. Concerning mCGH, no profile revealed chromosomal rearrangements. Conclusion: The benign ovarian teratoma remains a common ovarian neoplasm in young Congolese women in reproductive age. The predominant skin tissue form signed the current called ovarian dermoid cyst. The CGH analysis in our study revealed that pathology is not associated with chromosomal anomalies, but some associations are described in literature.

In Ivory Coast (West Africa) food crops are widely produced through a legume-cereal-tuber intermixed culture system. To assess the role and genetic diversity of rhizobial bacteria in this agronomic system, we isolated 74 rhizobial strains from root nodules of groundnut, soybean, and cowpea plants grown as intermixed cultures in fields all around the country. They all belonged to the Bradyrhizobium species (16S rDNA sequencing) with a large genetic diversity (16S-23S rDNA intertranscribed spacer [ITS] sequencing). They formed 17 clusters, some corresponding to B. japonicum, B. elkanii, B. yuanmingense, some to Bradyrhizobium spp. reference genospecies Ia, IV, V, VIII, XI [1], and six separate groups. We further performed MultiLocus Sequence analysis on five housekeeping genes (gnlII, recA, dnaK, rpoB, and atpD), using several phylogenetic methods (MP, ML, Bayesian), and obtained a consensus phylogenetic tree. Greenhouse tests were performed to screen the new strains for (i) their nitrogen-fixing potential on groundnut, soybean, and cowpea, and (ii) their plant growth promotion capacity on maize. Eight weeks after inoculation, plants were surveyed for their nodule numbers and dry weights, aerial part and root dry weight, leaf color, and ARA. Statistical analysis show that all strains (100%) are efficient on cowpea, 26% on groundnut (separate genospecies clusters 3, 8, 9, and 10), and 27% on soybean (B. japonicum cl. I, Ia, B. elkanii, cl. II, B. yuanmingense). Six strains (STM3040, STM3080, STM3078, STM3088, STM3070, and STM3079) were selected for their growth promotion on both legumes and cereal. Biochemicals tests showed ammonium production in STM3078, siderophores production in STM3080, STM3078, and STM3088. No AIA production nor phosphate solubilization were detected. Further investigations for 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, ACC gene sequencing, and endophytic functions are in progress and will be discussed. (Texte intégral)

In Côte d'Ivoire food crops are widely produced through a legume-cereal-tuber intermixed culture system. To assess the role and genetic diversity of rhizobial bacteria in this agronomic system, we isolated 74 rhizobial strains from root nodules of groundnut, soybean and cowpea plants in intermixed culture fields all around the country. All strains belonged to Bradyrhizobium (16S rDNA sequencing) and genetically diversity (165-23 5 rDNA inter-transcribed spacer -ITS- sequencing). They formed 15 clusters, some corresponding to B. japonicum I and la, B. elkanii, some to Bradyrhirobium spp. reference genospecies IV, X, XI**, and nine separate groups . We further performed Multi Locus Sequence analysis on six housekeeping genes (gnlll, recA, dnalf, rpoB, atpD , gyrB), using several phylogenetic methods (MP, ML, Bayesian), and obtained a consensus phylogenetic tree. Greenhouse tests were performed to screen the new strains for (1) their nitrogen-fixation potential on groundnut, soybean and cowpea and (2) their plant growth promotion capacity on maize. Eight weeks after inoculation plants were surveyed for their nodule numbers and dry weights, aerial part and root dry weights, leaf color, an d ARA. Statistical analysis show that all strains (100 °Io) are efficient on cowpea, 26 % on groundnut (separate genospecies clusters 3, 8, 9, 10), and 27 % on soybean (B. japonicum cl. I, Ia, B. elkanii, cl. II, B. yuanmingense). Six strains (STM 3040, STM 3080, STM 3078, STM 3088, STM 3070, STM 3079) were selected for their growth promotion on the three legumes and maize . Biochemical tests showed ammonium production in STM 3078, siderophore production in STM 3080, STM 3078, STM 3088 . Neither AIA production nor phosphate solubilization was detected. Further investigations for ACC déaminase activity, ACC gen e sequencing are in progress. Maize root cell colonization was observed by light microscopy using a GUS-labelled derivative of strain STM 3079. The invasion process involved large quantities of bacteria colonizing cracks at lateral root junctions and progressing more deeply towards pericycle via intracellular parenchyma. Further tests, on more beneficial strains are in progress. (Texte intégral)

Des souches de #Rhizobium$ isolées de #Sesbania rostrata$ provenant de différents lieux géographiques du Sénégal, ont été analysées. Leur comparaison avec la "souche de tige" de référence ORS571 a permis de mettre en évidence des différences au niveau des parentés immunologiques, du contenu plasmidique, de l'activité nitrogénase en condition de dérépression, et de l'efficience de la symbiose. L'azote combiné, ammoniacal ou nitrique affecte à la fois la nodulation et l'activité réductrice d'acétylène des nodules caulinaires et racinaires, mais les nodules racinaires sont plus affectés que les nodules caulinaires. L'étude cytologique des nodules caulinaires en microscopie électronique a montré qu'en présence de fortes doses d'azote combiné la dernière phase du processus de l'infection caulinaire (libération des bactéries du cordon d'infection dans le cytoplasme des cellules du méristème nodulaire) est bloquée. Des cycles végétatifs successifs initiés toutes les deux semaines tout au long de l'année ont permis de montrer que ches #S. rostrata$ le développement et la fixation d'azote sont très sensibles aux conditions climatiques en particulier à la photopériode et la température. Les potentialités fixatrices de #S. rostrata$ ont été évaluées par deux méthodes, la méthode par différence et la méthode de dilution isotopique N-15. La quantité d'azote fixée par #S. rostrata$ en 53 jours a été évaluée à environ 300 kg N/ha. Il est apparu que #S. rostrata$ utilisé comme engrais vert peut être bénéfique non seulement pour la culture irriguée du riz, mais également en culture exondée (riz et sorgho). Les essais correspondants ont été effectués à la station ORSTOM Bel-Air de Dakar et en milieu paysan en Casamance (Sud du Sénégal). (Résumé d'auteur)