Synthesis, in vitro and in vivo evaluation of 3β-[18F]fluorocholic acid for the detection of drug-induced cholestasis in mice

Introduction : Drug-induced cholestasis is a liver disorder that might be caused by interference of drugs with the hepatobiliary bile acid transporters. It is important to identify this interference early on in drug development. In this work, Positron Emission Tomography (PET)-imaging with a F-18 labeled bile acid analogue was introduced to detect disturbed hepatobiliary transport of bile acids. Methods : 3 beta-[F-18]fluorocholic acid ([F-18]FCA) was prepared by nucleophilic substitution of a mesylated precursor with [F-18]fluoride, followed by deprotection with sodium hydroxide. Transport of [F-18]FCA was assessed in vitro using CHO-NTCP, HEK-OATP1B1, HEK-OATP1B3 transfected cells and BSEP & MRP2 membrane vesicles. Investigation of [F-18]FCA metabolites was performed with primary mouse hepatocytes. Hepatobiliary transport of [F-18]FCA was evaluated in vivo in wild-type, rifampicin and bosentan pretreated FVB-mice by dynamic mu PET scanning. Results : Radiosynthesis of [F-18] FCA was achieved in a moderate radiochemical yield (8.11-1.94%; non-decay corrected; n = 10) and high radiochemical purity (>99%). FCA was transported by the basolateral bile acid uptake transporters NTCP, OATP1B1 and OATP1B3. For canalicular efflux, BSEP and MRP2 are the relevant bile acid transporters. [F-18]FCA was found to be metabolically stable. In vivo, [F-18]FCA showed fast hepatic uptake (4.5-0.5 min to reach 71.8-1.2% maximum % ID) and subsequent efflux to the gallbladder and intestines (93.3-6.0% ID after 1 hour). Hepatobiliary transport of [F-18]FCA was significantly inhibited by both rifampicin and bosentan. Conclusion : A F-18 labeled bile acid analogue, [F-18]FCA, has been developed that shows transport by NTCP, OATP, MRP2 and BSEP. [F-18]FCA can be used as a probe to monitor disturbed hepatobiliary transport in vivo and accumulation of bile acids in blood and liver during drug development

Identification of the transcriptional response of human intestinal mucosa to Lactobacillus plantarum WCFS1 in vivo

Contains fulltext : 69887.pdf ( ) (Open Access)BACKGROUND: There is limited knowledge on the extent and dynamics of the mucosal response to commensal and probiotic species in the human intestinal lumen. This study aimed to identify the acute, time-dependent responses of intestinal mucosa to commensal Lactobacillus plantarum WCFS1 in vivo in two placebo-controlled human intervention studies in healthy volunteers. Transcriptional changes in duodenal mucosa upon continuous intraduodenal infusion of L. plantarum WCFS1 for one- and six h, respectively, were studied using oro- and nasogastric intubations with dedicated orogastric catheters and tissue sampling by standard flexible gastroduodenoscopy. RESULTS: One- and six-h exposure of small intestinal mucosa to L. plantarum WCFS1 induced differential expression of 669 and 424 gene reporters, respectively. While short-term exposure to L. plantarum WCFS1 inhibited fatty acid metabolism and cell cycle progression, cells switched to a more proliferative phase after prolonged exposure with an overall expression profile characterized by upregulation of genes involved in lipid metabolism, cellular growth and development. Cell death and immune responses were triggered, but cell death-executing genes or inflammatory signals were not expressed. Proteome analysis showed differential expression of several proteins. Only the microsomal protein 'microsomal triglyceride transfer protein' was regulated on both the transcriptional and the protein level in all subjects. CONCLUSION: Overall, this study showed that intestinal exposure to L. plantarum WCFS1 induced consistent, time-dependent transcriptional responses in healthy intestinal mucosa. This extensive exploration of the human response to L. plantarum WCFS1 could eventually provide molecular support for specific or probiotic activity of this strain or species, and exemplifies the strength of the applied technology to identify the potential bio-activity of microbes in the human intestine

The role of trust and health literacy in nurse-delivered point-of-care STI testing for pregnant women living with HIV, Tshwane District, South Africa

Abstract Background Sexually transmitted infections (STIs) during pregnancy result in neonatal morbidity and mortality, and may increase mother-to-child-transmission of HIV. Yet the World Health Organization’s current syndromic management guidelines for STIs leaves most pregnant women undiagnosed and untreated. Point-of-care (POC) diagnostic tests for STIs can drastically improve detection and treatment. Though acceptable and feasible, poor medication adherence and re-infection due to lack of partner treatment threaten the programmatic effectiveness of POC diagnostic programmes. Methods To engender patient-provider trust, and improve medication adherence and disclosure of STI status to sexual partners, we trained study nurses in compassionate care, good clinical practices and motivational interviewing. Using qualitative methods, we explored the role patient-provider communications may play in supporting treatment adherence and STI disclosure to sexual partners. Nurses were provided training in motivational interviewing, compassionate care and good clinical practices. Participants were interviewed using a semi-structured protocol, with domains including STI testing experience, patient-provider communication, and HIV and STI disclosure. Interviews were audio-recorded, transcribed and analyzed using a constant comparison approach. Results Twenty-eight participants treated for Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), and/or Neisseria gonorrhea (NG) were interviewed. Participants described strong communications and trusting relationships with nurses trained in patient-centered care training and implementing POC STI diagnostic testing. However, women described a delayed trust in treatment until their symptoms resolved. Women expressed a limited recall of their exact diagnosis, which impacted their ability to fully disclose their STI status to sexual partners. Conclusions We recommend implementing patient health literacy programmes as part of POC services to support women in remembering and disclosing their specific STI diagnosis to sexual partners, which may facilitate partner treatment uptake and thus decrease the risk of re-infection

Persistent Chlamydia trachomatis, Neisseria gonorrhoeae or Trichomonas vaginalis positivity after treatment among human immunodeficiency virus-infected pregnant women, South Africa

The objective of this study is to assess the predictors and frequency of persistent sexually transmitted infection (STI) positivity in human immunodeficiency virus (HIV)-infected pregnant women treated for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) or Trichomonas vaginalis (TV) infection. We enrolled HIV-infected pregnant women attending their first antenatal care visit and tested them for urogenital CT, NG and TV infection using Xpert® CT/NG and TV assays (Cepheid, Sunnyvale, CA). Those testing positive were treated. Participants either notified partners to seek treatment or were given extra medication to deliver to partners for treatment. Repeat testing was conducted approximately 21 days post-treatment or treatment initiation. Among 427 participants, 172 (40.3%) tested positive for any STI. Of the 136 (79.1%) that returned for repeat testing, 36 (26.5%) tested positive for the same organism: CT = 27 (26.5%), NG = 1 (6.3%), TV = 11 (16.7%). Persistent CT positivity was independently associated with having more than one sex partner in the preceding 12 months (adjusted-prevalence ratio [aPR] = 3.03, 95% CI: 1.44–6.37) and being newly diagnosed with HIV infection during the first antenatal care visit compared to those currently on antiretroviral therapy (aPR = 3.97, 95% CI: 1.09–14.43). Persistent TV positivity was associated with not knowing if a partner sought treatment following STI disclosure (aPR = 12.6, 95% CI: 2.16–73.5) and prior diagnosis of HIV but not currently on antiretroviral therapy. (aPR = 4.14; 95% CI: 1.25–13.79). We identified a high proportion of HIV-infected pregnant women with persistent CT or TV positivity after treatment. To decrease the risk of re-infection, enhanced strategies for partner treatment programmes are needed to improve the effectiveness of STI screening and treatment in pregnancy. The relationship between not being on antiretroviral therapy and persistent STI positivity needs further study.The Eunice Kennedy Shriver Institute of Child Health and Human Development, National Institutes of Health (NIH), award R21HD084274 and the President’s Emergency Plan for AIDS Relief through the United States Agency of the Cooperative Agreement AID 674-A-12-00017 funded this study. Noah Kojima was supported by the U.S. NIH Fogarty International Center (award number D43TW009343) and the University of California Global Health Institute. Christina A Muzny was supported by K23AI106957-01A1 from the National Institute of Allergy and Infectious Diseases.https://journals.sagepub.com/home/stdhj2021Medical MicrobiologyPaediatrics and Child Healt