Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the ...Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the major conceptual advances in oncology over the last few years has been the appreciation that cancer progression cannot be explained by aberrations in cancer cells themselves and is strongly influenced by the surrounding tumor environment. The mechanisms of ovarian cancer progression differ from that of other solid tumors because ovarian cancer cells primarily disseminate within the peritoneal cavity.Malignant peritoneal effusion accumulates in the peritoneal cavity during ovarian cancer progression. These exudative fluids act as a unique tumor environment providing a framework that orchestrates cellular and molecular changes contributing to aggressiveness and disease progression. The composition of ascites, which includes cellular and acellular components, constantly adapts during the course of the disease in response to various cellular cues originating from both tumor and stromal cells. The tumor environment that represents peritoneal effusions closely constitute an ecosystem, with specific cell types and signaling molecules increasing and decreasing during the course of the disease progression creating a single complex network. Although recent advances aiming to understand the ovarian tumor environment have focused one at a time on components, the net impact of the whole environment cannot be understood simply from its parts or outside is environmental context.展开更多
A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports...A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports(TIVAP). In this study, fabrication, conditioning and sterilization processes of antimicrobial lock solution(ALS) were detailed and completed by a stability study. Stability of ALS was conducted for12 months in vial(25 °C 7 2 °C, 60% 7 5% relative humidity(RH), and at 40 °C 7 2 °C, RH 75% 7 5%)and for 24 h and 72 h in TIVAP(40 °C 7 2 °C, RH 75% 7 5%). A stability indicating HPLC assay with UV detection for simultaneous quantification of gentamicin sulfate and EDTA-Na2 was developed. ALS was assayed by ion-pairing high performance liquid chromatography(HPLC) needing gentamicin derivatization, EDTA-Na2 metallocomplexation of samples and gradient mobile phase. HPLC methods to separate four gentamicin components and EDTA-Na2 were validated. Efficiency of sterility procedure and conditioning of ALS was confirmed by bacterial endotoxins and sterility tests. Physicochemical stability of ALS was determined by visual inspection, osmolality, pH, and sub-visible particle counting. Results confirmed that the stability of ALS in vials was maintained for 12 months and 24 h and 72 h in TIVAP.展开更多
The authors achieved a clinical study on the treatment of fulminant viral hepatitis by the transplantation of human fetal liver cells. 47fetal livers were used for 8 patients with a survival of 6 cases. The side-effec...The authors achieved a clinical study on the treatment of fulminant viral hepatitis by the transplantation of human fetal liver cells. 47fetal livers were used for 8 patients with a survival of 6 cases. The side-effects of this new therapy were analysed and the mechanism of action of fetal liver cells discussed.展开更多
MUC16 （CA125） has remained the mainstay for ovarian cancer assessment and management since the early 1980’s. With the exception of HE4, it is the only reliable serum biomarker for ovarian cancer. MUC16 belongs to a...MUC16 （CA125） has remained the mainstay for ovarian cancer assessment and management since the early 1980’s. With the exception of HE4, it is the only reliable serum biomarker for ovarian cancer. MUC16 belongs to a family of high-molecular weight glycoproteins known as mucins. The mucin family is comprised of large secreted transmembrane proteins that includes MUC1, MUC4 and MUC16. These mucins are often overexpressed in a variety of malignancies. MUC1 and MUC4 have been shown to contribute to breast and pancreatic tumorigenesis. Recent studies have uncovered unique biological functions for MUC16 that go beyond its role as a biomarker for ovarian cancer. Here, we provide an overview of the literature to highlight the importance of MUC16 in ovarian cancer tumorigenesis. We focus on the growing literature describing the role of MUC16 in proliferation, migration, metastasis, tumorigenesis and drug resistance. Accumulating experimental evidence suggest that the C-terminal domain of MUC16 is critical to mediate theses effects. The importance of MUC16 in the pathogenesis of ovarian cancer emphasizes the need to fully understand the signaling capabilities of MUC16 C-terminal domain to develop more effcient strategies for the successful treatment of ovarian cancer.展开更多
The work of Carl Woese and his colleagues of the Urbana University has been one of the most important breakthroughs in biology in the last century(for historical sketches,see Refs.1,2).Carl Woese pioneered the use of ...The work of Carl Woese and his colleagues of the Urbana University has been one of the most important breakthroughs in biology in the last century(for historical sketches,see Refs.1,2).Carl Woese pioneered the use of macromolecule sequences to decipher the relationships between all organisms,fulfilling Darwin's dream to get a“fairly true genealogical trees of each great kingdom of nature”3.He went even beyond this objective since he was finally able to identify and connect each great kingdom of nature(which he called domains)into a single tree.The apex of his work was the discovery in 1977 of an entire new domain of life,hidden before our eyes,the Archaea4.The use of 16S ribosomal RNA(rRNA)as a molecular chronometer and later as a probe for PCR not only revealed a third domain of life but also paved the way for the detection and identification of microorganisms that were not yet amenable to cultivation5.展开更多
Background Clostridium difficile,rarely found in hospitals,is a bacterium responsible for post-antibiotic diarrhea and Pseudomembranous Colitis(CPM).C.difficile selective pressure represents potential public health pr...Background Clostridium difficile,rarely found in hospitals,is a bacterium responsible for post-antibiotic diarrhea and Pseudomembranous Colitis(CPM).C.difficile selective pressure represents potential public health problem due to the production of toxins A and B serious pathologies effects/consequences.A transversal and analytic study was to assess the risk factors of C.difficile infection and to determine the prevalence of C.difficile in patients received in randomly selected five hospitals in Yaoundé,Cameroon.Methods A total of 300 stool samples were collected from consented patients using a transversal and analytic study conducted from 10th July to 10th November 2018 in five hospitals in Cameroon.The detection or diagnostic kit was CerTest C.difficile Glutamate Dehydrogenase+Toxin A+Toxin B based on immuno-chromatographic assay.A univariate and multivariate analysis allowed us to highlight the associated factors.Results The results showed a prevalence of C.difficile of 27.33%(82/300 stool patients’samples taken).Of these 27.33%,the production of Toxin A and Toxin B were 37.80 and 7.31%respectively.In univariate analysis,hospitalization was a significant(P=0.01)risk factor favoring C.difficile infection.In multivariate analysis,corticosteroids and quinolones use/administration were significantly(adjusted Odd Ratio,aOR=14.09,95%CI:1.62–122.54,P=0.02 and aOR=3.39,95%CI:1.00–11.34,P=0.05 respectively)risk factor for this infection.Conclusion The prevalence of C.difficile infections(CDI)remain high in these settings and may be related not only to permanent steroids and antibiotics.Promoting education to both medical staff and patients on the prevalence and public health impact of C.difficile can be core inimproving rationale prescription of steroids and antibiotics to patients and promote human health and exponential growth in Cameroon.展开更多
The discovery of Asgard archaea and the exploration of their diversity over the last 6 years have deeply impacted the scientific community working on eukaryogenesis,rejuvenating an intense debate on the topology of th...The discovery of Asgard archaea and the exploration of their diversity over the last 6 years have deeply impacted the scientific community working on eukaryogenesis,rejuvenating an intense debate on the topology of the universal tree of life(uTol).Here,we discuss how this debate is impacted by two recent publications that expand the number of Asgard lineages and eukaryotic signature proteins(ESPs).We discuss some of the main difficulties that can impair the phylogenetic reconstructions of the uTol and suggest that the debate about its topology is not settled.We notably hypothesize the existence of horizontal gene transfers between ancestral Asgards and proto-eukaryotes that could result in the observed abnormal behaviors of some Asgard ESPs and universal marker proteins.This hypothesis is relevant regardless of the scenario considered regarding eukaryogenesis.It implies that the Asgards were already diversified before the last eukaryotic common ancestor and shared the same biotopes with proto-eukaryotes.We suggest that some Asgards might be still living in symbiosis today with modern Eukarya.展开更多
Soil salinity, which affects more than 6% of the earth’s land surface and more than 20% of its irrigated areas, is a major threat to agriculture. Diazotrophic bacteria are among the functional groups of soil microbio...Soil salinity, which affects more than 6% of the earth’s land surface and more than 20% of its irrigated areas, is a major threat to agriculture. Diazotrophic bacteria are among the functional groups of soil microbiota that are threatened by this abiotic stress, as their activity is mostly inhibited by salt stress. Seventy bacterial strains with distinct characteristics were isolated from soils by using N-free Jensen’s selective medium. Based on their ability to produce metabolites of agricultural interest, four strains were selected and identified as Flavobacterium johnsoniae, Pseudomonas putida, Achromobacter xylosoxidans, and Azotobacter chroococcum. The selected strains were grown at different NaCl concentrations (0–600 mmol L^(-1) in N-free broth and 0–2 000 mmol L^(-1) in Luria-Bertani medium) in the presence and absence of glycine betaine (GB), aqueous and hydro-alcoholic extracts from marine macroalgae, Ulva lactuca and Enteromorpha intestinalis, and Opuntia ficus-indica cladodes. The selected bacterial strains, GB, and the aforementioned extracts were tested for their ability to promote the germination of wheat (Triticum durum) seeds at 0–300 mmol L^(-1) NaCl. Compared with the results obtained with the synthetic osmoprotectant GB, the extracts from O. ficus-indica, U. lactuca, and E. intestinalis significantly promoted bacterial growth and seed germination under salt stress.展开更多
文摘Until recently, ovarian cancer research has mainly focused on the tumor cells themselves ignoring for the most part the surrounding tumor environment which includes malignant peritoneal effusions. However, one of the major conceptual advances in oncology over the last few years has been the appreciation that cancer progression cannot be explained by aberrations in cancer cells themselves and is strongly influenced by the surrounding tumor environment. The mechanisms of ovarian cancer progression differ from that of other solid tumors because ovarian cancer cells primarily disseminate within the peritoneal cavity.Malignant peritoneal effusion accumulates in the peritoneal cavity during ovarian cancer progression. These exudative fluids act as a unique tumor environment providing a framework that orchestrates cellular and molecular changes contributing to aggressiveness and disease progression. The composition of ascites, which includes cellular and acellular components, constantly adapts during the course of the disease in response to various cellular cues originating from both tumor and stromal cells. The tumor environment that represents peritoneal effusions closely constitute an ecosystem, with specific cell types and signaling molecules increasing and decreasing during the course of the disease progression creating a single complex network. Although recent advances aiming to understand the ovarian tumor environment have focused one at a time on components, the net impact of the whole environment cannot be understood simply from its parts or outside is environmental context.
基金supported by Centre de Recherche Translationnelle de I'Institut Pasteur, grant Number S- PI15007-02Asupported by the French Government's Investissement d'Avenir program:Laboratoire d'Excellence ‘Integrative Biology of Emerging Infectious Diseases’ (grant no. ANR-10-LABX62-IBEID.)+1 种基金the Fondation pour la Recherche Médicale (grant no. DEQ. 20140329508)the Center for Translational Science of the Institut Pasteur (S-PI15007-02A)
文摘A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports(TIVAP). In this study, fabrication, conditioning and sterilization processes of antimicrobial lock solution(ALS) were detailed and completed by a stability study. Stability of ALS was conducted for12 months in vial(25 °C 7 2 °C, 60% 7 5% relative humidity(RH), and at 40 °C 7 2 °C, RH 75% 7 5%)and for 24 h and 72 h in TIVAP(40 °C 7 2 °C, RH 75% 7 5%). A stability indicating HPLC assay with UV detection for simultaneous quantification of gentamicin sulfate and EDTA-Na2 was developed. ALS was assayed by ion-pairing high performance liquid chromatography(HPLC) needing gentamicin derivatization, EDTA-Na2 metallocomplexation of samples and gradient mobile phase. HPLC methods to separate four gentamicin components and EDTA-Na2 were validated. Efficiency of sterility procedure and conditioning of ALS was confirmed by bacterial endotoxins and sterility tests. Physicochemical stability of ALS was determined by visual inspection, osmolality, pH, and sub-visible particle counting. Results confirmed that the stability of ALS in vials was maintained for 12 months and 24 h and 72 h in TIVAP.
文摘The authors achieved a clinical study on the treatment of fulminant viral hepatitis by the transplantation of human fetal liver cells. 47fetal livers were used for 8 patients with a survival of 6 cases. The side-effects of this new therapy were analysed and the mechanism of action of fetal liver cells discussed.
基金Supported by Internal Funding from Universitéde Sherbrooke
文摘MUC16 （CA125） has remained the mainstay for ovarian cancer assessment and management since the early 1980’s. With the exception of HE4, it is the only reliable serum biomarker for ovarian cancer. MUC16 belongs to a family of high-molecular weight glycoproteins known as mucins. The mucin family is comprised of large secreted transmembrane proteins that includes MUC1, MUC4 and MUC16. These mucins are often overexpressed in a variety of malignancies. MUC1 and MUC4 have been shown to contribute to breast and pancreatic tumorigenesis. Recent studies have uncovered unique biological functions for MUC16 that go beyond its role as a biomarker for ovarian cancer. Here, we provide an overview of the literature to highlight the importance of MUC16 in ovarian cancer tumorigenesis. We focus on the growing literature describing the role of MUC16 in proliferation, migration, metastasis, tumorigenesis and drug resistance. Accumulating experimental evidence suggest that the C-terminal domain of MUC16 is critical to mediate theses effects. The importance of MUC16 in the pathogenesis of ovarian cancer emphasizes the need to fully understand the signaling capabilities of MUC16 C-terminal domain to develop more effcient strategies for the successful treatment of ovarian cancer.
文摘The work of Carl Woese and his colleagues of the Urbana University has been one of the most important breakthroughs in biology in the last century(for historical sketches,see Refs.1,2).Carl Woese pioneered the use of macromolecule sequences to decipher the relationships between all organisms,fulfilling Darwin's dream to get a“fairly true genealogical trees of each great kingdom of nature”3.He went even beyond this objective since he was finally able to identify and connect each great kingdom of nature(which he called domains)into a single tree.The apex of his work was the discovery in 1977 of an entire new domain of life,hidden before our eyes,the Archaea4.The use of 16S ribosomal RNA(rRNA)as a molecular chronometer and later as a probe for PCR not only revealed a third domain of life but also paved the way for the detection and identification of microorganisms that were not yet amenable to cultivation5.
文摘Background Clostridium difficile,rarely found in hospitals,is a bacterium responsible for post-antibiotic diarrhea and Pseudomembranous Colitis(CPM).C.difficile selective pressure represents potential public health problem due to the production of toxins A and B serious pathologies effects/consequences.A transversal and analytic study was to assess the risk factors of C.difficile infection and to determine the prevalence of C.difficile in patients received in randomly selected five hospitals in Yaoundé,Cameroon.Methods A total of 300 stool samples were collected from consented patients using a transversal and analytic study conducted from 10th July to 10th November 2018 in five hospitals in Cameroon.The detection or diagnostic kit was CerTest C.difficile Glutamate Dehydrogenase+Toxin A+Toxin B based on immuno-chromatographic assay.A univariate and multivariate analysis allowed us to highlight the associated factors.Results The results showed a prevalence of C.difficile of 27.33%(82/300 stool patients’samples taken).Of these 27.33%,the production of Toxin A and Toxin B were 37.80 and 7.31%respectively.In univariate analysis,hospitalization was a significant(P=0.01)risk factor favoring C.difficile infection.In multivariate analysis,corticosteroids and quinolones use/administration were significantly(adjusted Odd Ratio,aOR=14.09,95%CI:1.62–122.54,P=0.02 and aOR=3.39,95%CI:1.00–11.34,P=0.05 respectively)risk factor for this infection.Conclusion The prevalence of C.difficile infections(CDI)remain high in these settings and may be related not only to permanent steroids and antibiotics.Promoting education to both medical staff and patients on the prevalence and public health impact of C.difficile can be core inimproving rationale prescription of steroids and antibiotics to patients and promote human health and exponential growth in Cameroon.
文摘The discovery of Asgard archaea and the exploration of their diversity over the last 6 years have deeply impacted the scientific community working on eukaryogenesis,rejuvenating an intense debate on the topology of the universal tree of life(uTol).Here,we discuss how this debate is impacted by two recent publications that expand the number of Asgard lineages and eukaryotic signature proteins(ESPs).We discuss some of the main difficulties that can impair the phylogenetic reconstructions of the uTol and suggest that the debate about its topology is not settled.We notably hypothesize the existence of horizontal gene transfers between ancestral Asgards and proto-eukaryotes that could result in the observed abnormal behaviors of some Asgard ESPs and universal marker proteins.This hypothesis is relevant regardless of the scenario considered regarding eukaryogenesis.It implies that the Asgards were already diversified before the last eukaryotic common ancestor and shared the same biotopes with proto-eukaryotes.We suggest that some Asgards might be still living in symbiosis today with modern Eukarya.
文摘Soil salinity, which affects more than 6% of the earth’s land surface and more than 20% of its irrigated areas, is a major threat to agriculture. Diazotrophic bacteria are among the functional groups of soil microbiota that are threatened by this abiotic stress, as their activity is mostly inhibited by salt stress. Seventy bacterial strains with distinct characteristics were isolated from soils by using N-free Jensen’s selective medium. Based on their ability to produce metabolites of agricultural interest, four strains were selected and identified as Flavobacterium johnsoniae, Pseudomonas putida, Achromobacter xylosoxidans, and Azotobacter chroococcum. The selected strains were grown at different NaCl concentrations (0–600 mmol L^(-1) in N-free broth and 0–2 000 mmol L^(-1) in Luria-Bertani medium) in the presence and absence of glycine betaine (GB), aqueous and hydro-alcoholic extracts from marine macroalgae, Ulva lactuca and Enteromorpha intestinalis, and Opuntia ficus-indica cladodes. The selected bacterial strains, GB, and the aforementioned extracts were tested for their ability to promote the germination of wheat (Triticum durum) seeds at 0–300 mmol L^(-1) NaCl. Compared with the results obtained with the synthetic osmoprotectant GB, the extracts from O. ficus-indica, U. lactuca, and E. intestinalis significantly promoted bacterial growth and seed germination under salt stress.
