First detection of Waddlia chondrophila in Africa using SYBR Green real-time PCR on veterinary samples.

Waddlia chondrophila is a strict intracellular microorganism belonging to the order Chlamydiales that has been isolated twice from aborted bovine fetuses, once in USA and once in Germany. This bacterium is now considered as an abortigenic agent in cattle. However, no information is available regarding the presence of this bacterium in Africa. Given the low sensitivity of cell culture to recover such an obligate intracellular bacterium, molecular-based diagnostic approaches are warranted. This report describes the development of a quantitative SYBR Green real-time PCR assay targeting the recA gene of W. chondrophila. Analytical sensitivity was 10 copies of control plasmid DNA per reaction. No cross-amplification was observed when testing pathogens that can cause abortion in cattle. The PCR exhibited a good intra-run and inter-run reproducibility. This real-time PCR was then applied to 150 vaginal swabs taken from Tunisian cows that have aborted. Twelve samples revealed to be Waddlia positive, suggesting a possible role of this bacterium in this setting. This new real-time PCR assay represents a diagnostic tool that may be used to further study the prevalence of Waddlia infection

Molecular prevalence of Chlamydia and Chlamydia-like bacteria in Tunisian domestic ruminant farms and their influencing risk factors

Chlamydia and Chlamydia-like bacteria are well known to infect several organisms and may cause a wide range of diseases, particularly in ruminants. To gain insight into the prevalence and diversity of these intracellular bacteria, we applied a pan-Chlamydiales real-time PCR to 1,134 veterinary samples taken from 130 Tunisian ruminant herds. The true adjusted animal population-level prevalence was 12.9% in cattle, against 8.7% in sheep. In addition, the true adjusted herd-level prevalence of Chlamydiae was 80% in cattle and 25.5% in sheep. Chlamydiales from three familylevel lineages were detected indicating a high biodiversity of Chlamydiales in ruminant herds. Our results showed that Parachlamydia acanthamoebae could be responsiblefor bovine and ovine chlamydiosis in central-eastern Tunisia. Multivariable logistic regression analysis at the animal population level indicated that strata and digestive disorders variables were the important risk factors of bovine and ovine chlamydiosis. However, origin and age variables were found to be associated withbovine and ovine chlamydiosis, respectively. At the herd level, risk factors for Chlamydia positivity were as follows: abortion and herd size for cattle against breeding system, cleaning frequency, quarantine, use of disinfectant and floor type for sheep. Paying attention to these risk factors will help improvement of control programs against this harmful zoonotic disease

Frequency of Chlamydia trachomatis in Ureaplasma-positive healthy women attending their first prenatal visit in a community hospital in Sapporo, Japan

<p>Abstract</p> <p>Background</p> <p>Although <it>Chlamydia trachomatis </it>is the most commonly reported pathogen that causes urogenital infection such as urethritis or cervicitis, <it>Ureaplasma parvum </it>and <it>Ureaplasma urealyticum</it>, which are commensals in the genital tract, have also now been recognized as contributors to urogenital infection. However, whether the presence of either <it>U. parvum </it>or <it>U. urealyticum </it>is related to that of <it>C. trachomatis </it>in the urogenital tract remains unknown. We therefore attempted to estimate by PCR the prevalence of <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum </it>in endocervical samples obtained from healthy women attending their first prenatal visit in Sapporo, Japan.</p> <p>Methods</p> <p>The samples were taken from 303 apparently healthy women, and the extracted DNAs (<it>n </it>= 280) were used for PCR detection targeting <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum</it>. Statistical analysis of the data was performed by Fisher's exact test.</p> <p>Results</p> <p>PCR detection revealed that the prevalence of <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum </it>was 14.3% (40/280), 41.7% (117/280) and 8.9% (25/280), respectively. <it>C. trachomatis ompA </it>genotype D was most frequently identified. Surprisingly, either <it>C. trachomatis </it>or <it>Ureaplasma </it>spp. was detected in almost half of the healthy women. Mixed infection of <it>C. trachomatis </it>with either <it>U. parvum </it>or <it>U. urealyticum </it>was also observed in 9.2% (26/280) of the women. There was a significant association between <it>C. trachomatis </it>and either <it>U. parvum </it>(<it>p </it>= 0.023) or <it>Ureaplasma </it>total (<it>p </it>= 0.013), but not <it>U. urealyticum </it>(<it>p </it>= 0.275).</p> <p>Conclusion</p> <p>This study demonstrated that the presence of <it>Ureaplasma </it>had a significant effect on the presence of <it>C. trachomatis </it>in the genital tract of healthy women, suggesting that mixed infection is an important factor in bacterial pathogenesis in the genital tract.</p

Books in Arabic Script

The chapter approaches the book in Arabic script as the indispensable means for the transmission of knowledge across Eurasia and Africa, within cultures and across cultural boundaries, since the seventh century ad. The state of research can be divided into manuscript and print studies, but there is not yet a history of the book in Arabic script that captures its plurilinear development for over fourteen hundred years. The chapter explores the conceptual and practical challenges that impede the integration of the book in Arabic script into book history at large and includes an extensive reference list that reflects its diversity. The final published version was slightly updated, and includes seven illustrations of six Qurans from the holdings of Columbia University Libraries, four manuscripts and two printed versions. Moreover, the illustrations are images of historical artifacts which are in the public domain - despite Wiley's copyright claim

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Prévalence et caractérisation toxigénique et antibiotypique des souches de Bacillus cereus isolées des denrées alimentaires en Tunisie

Les bactéries du groupe Bacillus cereus sont ubiquitaires sporulées et reconnues comme des pathogènes opportunistes pouvant contaminer un grand nombre d’aliments. Notre travail porte sur l’étude de la prévalence, de la diversité génétique et du pouvoir pathogène de souches du groupe B. cereus. Au total, 687 échantillons (céréales ; épices ; plats cuisinés ; salades ; viandes de volailles crues et cuites ; produits pâtissiers, laitiers, de conserve et de la mer) ont été collectés en Tunisie afin d’évaluer leur taux de contamination par dénombrement sur gélose MYP. Parmi les colonies présomptives (uniformes, de couleur rose-orange et entourées d'une zone de précipitation), une seule a été repiquée par échantillon et conservée en cryoculture. Cent-quatre-vingt-onze échantillons (27,8% des échantillons) positifs ont ainsi donné lieu à la création d’une collection de 191 isolats du groupe B. cereus. Pour 77,5% des échantillons, le taux de contamination s’est avéré être inférieur à 103 cfu/ g- ml. Des concentrations plus élevées (> 104 cfu/ g- ml) ont été observées dans 6,8% des échantillons, y compris les salades, les plats cuisinés, les céréales et les produits pâtissiers. Les isolats présomptifs du groupe B. cereus ont fait l’objet d’une identification par un test PCR ciblant la séquence du gène sspE, spécifique du groupe. Ainsi, 174 isolats se sont avérés positifs. Le pourcentage d'échantillons contaminés était de 67.6 %, 46.2 %, 40.8%, 32.7%, 32.3%, 28.8%, 16.7%, 9.4%, 5.0% et 4,8% dans la catégorie des céréales, produits pâtissiers, aliments, viande de volaille cuite, produits de la mer, épices, conserves, viande de volaille crue, salades et produits laitiers, respectivement.La diversité génétique a été évaluée par des méthodes de typage moléculaire : l’ERIC-PCR et la PFGE. L'analyse des profils PFGE et ERIC-PCR a permis de discriminer 143 et 99 clusters différents, respectivement. Afin d’étudier leur pouvoir pathogène, les isolats du groupe B. cereus ont fait l’objet d’une évaluation du pouvoir pathogène : présence de gènes de virulence, activité cytotoxique sur cellules Caco-2 et résistance aux antibiotiques. Les résultats ont montré la présence des gènes codant pour les entérotoxines suivantes : hblA (29.9%), hblB (14.9%), hblC (54.6%), hblD (54.6%), nheA (98.9%), nheB (86.8%), nheC (97.7%), cytK (37.9%) et bceT (50.6%). Le gène codant pour le céreulide n’a été mis en évidence que chez 7 isolats (4%). La distribution des différents gènes de virulence au sein de la collection a permis de classer les souches en douze groupes. Après incubation en milieu BHI-YE à 30°C, 70,7% et 35% des souches se sont avérées cytotoxiques (provoquant plus de 50% d'inhibition des cellules Caco-2) après 18 h et 5 j, respectivement. Un lien apparait clairement entre la cytotoxicité des souches et le type d’aliment dont elles sont issues. Cependant, aucun des facteurs de virulence n'a pu, individuellement ou en combinaison, expliquer la cytotoxicité des souches étudiées. La majorité des souches s’est montrée sensible à de nombreux agents antimicrobiens mais présentait une résistance à l'ampicilline et à la novobiocine. L’ensemble de ces données souligne l’importance de contrôler le risque associé à la présence de ces bactéries dans les aliments tunisiens

Chemical composition and antioxidant activity of Marrubium vulgare L. essential oil from Tunisia

In this study, the essential oil of the aerial parts of Marrubium vulgare L. obtained by hydrodistillation was analyzed by gas chromatography coupled to mass spectrometry (GC-MS) in order to determine their chemical composition. Thirty-four (34) components in the oil of M. vulgare were identified. The results demonstrated that the major components of the essential oil were y-eudesmol (11.93%),β - citronellol (9.90%), citronellyl formate (9.50%) and germacrene D (9.37%). Antioxidant effectiveness was examined by three different methods: The DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, the β-carotene bleaching test and the reducing power assay. The results showed that this oil can be considered an effective source of antioxidants of natural origin. This is the first report on chemical composition of M. vulgare essential oil cultivated in Tunisia and the original study on the antioxidant activity of M. vulgare essential oil.Key words: Marrubium vulgare, essential oil, chemical composition, antioxidant activity

Chlamydia trachomatis infection increases the expression of inflammatory tumorigenic cytokines and chemokines as well as components of the Toll-like receptor and NF-κB pathways in human prostate epithelial cells

Inflammation has been reported to play a major role in prostate carcinogenesis. Several bacterial infections can lead to prostate inflammation; however, until now, the precise molecular and cellular mechanisms linking inflammation to carcinogenesis have remained unclear. We therefore investigated the initiation of inflammation induced by Chlamydia trachomatis (C. trachomatis) infection in human prostate epithelial cells using an in vitro culture system in which human androgen-independent PC-3 prostate cancer epithelial cells were infected with C. trachomatis serovar L2. The expression levels of VEGF, ICAM-1, IL-6, IL-8, IL-1β, TNFα, CCL5, CCL2 and iNOS inflammation-related genes, as well as genes involved in the Toll-like receptor (TLR) pathway (TLR2, TLR4, CD14 and MyD88), were evaluated at the mRNA level in infected PC-3 cells 24 h after infection with C. trachomatis serovar L2. The expression levels of components of the NF-κB pathway (p65 and IκBα) were evaluated at the mRNA level in infected PC-3 cells at different time points (1, 6, 12 and 24 h) after infection. The expression levels of inflammation-related genes, components of the Toll-like receptor pathway and genes involved in NF-κB activation were analyzed in infected and uninfected cells using semi-quantitative RT-PCR. We detected a significant increase (p \u3c 0.001) in inflammation-related cytokines in infected PC-3 cells. During infection, PC-3 cells elicited a proinflammatory response, as shown by NF-κB activation, TLR2 and TLR4 upregulation and the increased expression of inflammation-related genes. Furthermore, we observed significant upregulation of the adhesion molecules ICAM-1 and VEGF, which are two biomarkers correlated with tumor progression and immune system evasion. The present study suggests that human prostate cancer epithelial cells are susceptible to C. trachomatis infection and upregulate proinflammatory markers during infection

Chemical composition and in vitro antioxidant activities of Thymelaea hirsuta L. essential oil from Tunisia

This study was designed to examine for the first time, the chemical composition and in vitro antioxidant activities of the essential oil obtained from the aerial parts of Thymelaea hirsuta L. The essential oil was subjected to hydrodistillation and was analyzed by GC-FID and GC-MS. The chemical composition was dominated by the presence of hydrocarbon sesquiterpenes (26.91%) with germacrene D (12.98%) as the major component, while oxygenated sesquiterpenes and monoterpenes amounted to 13.82 and 13.29%, respectively. The antioxidant properties of the studied essential oil were determined by three methods: diphenylpicrylhydrazyl (DPPH) assay, -carotene bleaching assay and reducing power test and the results were compared to the reference BHT (butyl hydroxy toluene). In the three earlier mentioned assays, the essential oil demonstrated a potential antioxidant which may be considered as potent agent in food preservation and drug discovery.Key words: Thymelaea hirsuta, essential oil, antioxidant activities