Regulation of daptomycin biosynthesis in Streptomyces roseosporus: new insights from genomic analysis and synthetic biology to accelerate lipopeptide discovery and commercial production.

Baltz RH 《-》

Global burden of bacterial antimicrobial resistance 1990-2021: a systematic analysis with forecasts to 2050.

Antimicrobial resistance (AMR) poses an important global health challenge in the 21st century. A previous study has quantified the global and regional burden of AMR for 2019, followed with additional publications that provided more detailed estimates for several WHO regions by country. To date, there have been no studies that produce comprehensive estimates of AMR burden across locations that encompass historical trends and future forecasts. We estimated all-age and age-specific deaths and disability-adjusted life-years (DALYs) attributable to and associated with bacterial AMR for 22 pathogens, 84 pathogen-drug combinations, and 11 infectious syndromes in 204 countries and territories from 1990 to 2021. We collected and used multiple cause of death data, hospital discharge data, microbiology data, literature studies, single drug resistance profiles, pharmaceutical sales, antibiotic use surveys, mortality surveillance, linkage data, outpatient and inpatient insurance claims data, and previously published data, covering 520 million individual records or isolates and 19 513 study-location-years. We used statistical modelling to produce estimates of AMR burden for all locations, including those with no data. Our approach leverages the estimation of five broad component quantities: the number of deaths involving sepsis; the proportion of infectious deaths attributable to a given infectious syndrome; the proportion of infectious syndrome deaths attributable to a given pathogen; the percentage of a given pathogen resistant to an antibiotic of interest; and the excess risk of death or duration of an infection associated with this resistance. Using these components, we estimated disease burden attributable to and associated with AMR, which we define based on two counterfactuals; respectively, an alternative scenario in which all drug-resistant infections are replaced by drug-susceptible infections, and an alternative scenario in which all drug-resistant infections were replaced by no infection. Additionally, we produced global and regional forecasts of AMR burden until 2050 for three scenarios: a reference scenario that is a probabilistic forecast of the most likely future; a Gram-negative drug scenario that assumes future drug development that targets Gram-negative pathogens; and a better care scenario that assumes future improvements in health-care quality and access to appropriate antimicrobials. We present final estimates aggregated to the global, super-regional, and regional level. In 2021, we estimated 4·71 million (95% UI 4·23-5·19) deaths were associated with bacterial AMR, including 1·14 million (1·00-1·28) deaths attributable to bacterial AMR. Trends in AMR mortality over the past 31 years varied substantially by age and location. From 1990 to 2021, deaths from AMR decreased by more than 50% among children younger than 5 years yet increased by over 80% for adults 70 years and older. AMR mortality decreased for children younger than 5 years in all super-regions, whereas AMR mortality in people 5 years and older increased in all super-regions. For both deaths associated with and deaths attributable to AMR, meticillin-resistant Staphylococcus aureus increased the most globally (from 261 000 associated deaths [95% UI 150 000-372 000] and 57 200 attributable deaths [34 100-80 300] in 1990, to 550 000 associated deaths [500 000-600 000] and 130 000 attributable deaths [113 000-146 000] in 2021). Among Gram-negative bacteria, resistance to carbapenems increased more than any other antibiotic class, rising from 619 000 associated deaths (405 000-834 000) in 1990, to 1·03 million associated deaths (909 000-1·16 million) in 2021, and from 127 000 attributable deaths (82 100-171 000) in 1990, to 216 000 (168 000-264 000) attributable deaths in 2021. There was a notable decrease in non-COVID-related infectious disease in 2020 and 2021. Our forecasts show that an estimated 1·91 million (1·56-2·26) deaths attributable to AMR and 8·22 million (6·85-9·65) deaths associated with AMR could occur globally in 2050. Super-regions with the highest all-age AMR mortality rate in 2050 are forecasted to be south Asia and Latin America and the Caribbean. Increases in deaths attributable to AMR will be largest among those 70 years and older (65·9% [61·2-69·8] of all-age deaths attributable to AMR in 2050). In stark contrast to the strong increase in number of deaths due to AMR of 69·6% (51·5-89·2) from 2022 to 2050, the number of DALYs showed a much smaller increase of 9·4% (-6·9 to 29·0) to 46·5 million (37·7 to 57·3) in 2050. Under the better care scenario, across all age groups, 92·0 million deaths (82·8-102·0) could be cumulatively averted between 2025 and 2050, through better care of severe infections and improved access to antibiotics, and under the Gram-negative drug scenario, 11·1 million AMR deaths (9·08-13·2) could be averted through the development of a Gram-negative drug pipeline to prevent AMR deaths. This study presents the first comprehensive assessment of the global burden of AMR from 1990 to 2021, with results forecasted until 2050. Evaluating changing trends in AMR mortality across time and location is necessary to understand how this important global health threat is developing and prepares us to make informed decisions regarding interventions. Our findings show the importance of infection prevention, as shown by the reduction of AMR deaths in those younger than 5 years. Simultaneously, our results underscore the concerning trend of AMR burden among those older than 70 years, alongside a rapidly ageing global community. The opposing trends in the burden of AMR deaths between younger and older individuals explains the moderate future increase in global number of DALYs versus number of deaths. Given the high variability of AMR burden by location and age, it is important that interventions combine infection prevention, vaccination, minimisation of inappropriate antibiotic use in farming and humans, and research into new antibiotics to mitigate the number of AMR deaths that are forecasted for 2050. UK Department of Health and Social Care's Fleming Fund using UK aid, and the Wellcome Trust.

GBD 2021 Antimicrobial Resistance Collaborators 《-》

RETRACTED: Hydroxychloroquine and azithromycin as a treatment of COVID-19: results of an open-label non-randomized clinical trial.

Chloroquine and hydroxychloroquine have been found to be efficient on SARS-CoV-2, and reported to be efficient in Chinese COV-19 patients. We evaluate the effect of hydroxychloroquine on respiratory viral loads. French Confirmed COVID-19 patients were included in a single arm protocol from early March to March 16th, to receive 600mg of hydroxychloroquine daily and their viral load in nasopharyngeal swabs was tested daily in a hospital setting. Depending on their clinical presentation, azithromycin was added to the treatment. Untreated patients from another center and cases refusing the protocol were included as negative controls. Presence and absence of virus at Day6-post inclusion was considered the end point. Six patients were asymptomatic, 22 had upper respiratory tract infection symptoms and eight had lower respiratory tract infection symptoms. Twenty cases were treated in this study and showed a significant reduction of the viral carriage at D6-post inclusion compared to controls, and much lower average carrying duration than reported in the litterature for untreated patients. Azithromycin added to hydroxychloroquine was significantly more efficient for virus elimination. Despite its small sample size, our survey shows that hydroxychloroquine treatment is significantly associated with viral load reduction/disappearance in COVID-19 patients and its effect is reinforced by azithromycin. This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). Concerns have been raised regarding this article, the substance of which relate to the articles' adherence to Elsevier's publishing ethics policies and the appropriate conduct of research involving human participants, as well as concerns raised by three of the authors themselves regarding the article's methodology and conclusions. Elsevier's Research Integrity and Publishing Ethics Team, in collaboration with the journal's co-owner, the International Society of Antimicrobial Chemotherapy (ISAC), and with guidance from an impartial field expert acting in the role of an independent Publishing Ethics Advisor, Dr. Jim Gray, Consultant Microbiologist at the Birmingham Children's and Women's Hospitals, U.K., conducted an investigation and determined that the below points constituted cause for retraction: • The journal has been unable to confirm whether any of the patients for this study were accrued before ethical approval had been obtained. The ethical approval dates for this article are stated as being 5th and 6th of March 2020 (ANSM and CPP respectively), while the article states that recruitment began in “early March”. The 17th author, Prof. Philippe Brouqui, has confirmed that the start date for patient accrual was 6th March 2020. The journal has not been able to establish whether all patients could have entered into the study in time for the data to have been analysed and included in the manuscript prior to its submission on the 20th March 2020, nor whether all patients were enrolled in the study upon admission as opposed to having been hospitalised for some time before starting the treatment described in the article. Additionally, the journal has not been able to establish whether there was equipoise between the study patients and the control patients. • The journal has not been able to establish whether the subjects in this study should have provided informed consent to receive azithromycin as part of the study. The journal has concluded that that there is reasonable cause to conclude that azithromycin was not considered standard care at the time of the study. The 17th author, Prof. Philippe Brouqui has attested that azithromycin treatment was not, at the time of the study, an experimental treatment but a possible treatment for, or preventative measure against, bacterial superinfections of viral pneumonia as described in section 2.4 of the article, and as such the treatment should be categorised as standard care that would not require informed consent. This does not fully address the journal's concerns around the use of azithromycin in the study. In section 3.1 of the article, it is stated that six patients received azithromycin to prevent (rather than treat) bacterial superinfection. All of these were amongst the patients who also received hydroxychloroquine (HCQ). None of the control patients are reported to have received azithromycin. This would indicate that only patients in the HCQ arm received azithromycin, all of whom were in one center. The recommendations for use of macrolides in France at the time the study was conducted indicate that azithromycin would not have been a logical agent to use as first-line prophylaxis against pneumonia due to the frequency of macrolide resistance amongst bacteria such as pneumococci. These two points suggest that azithromycin would not have been standard practice across southern France at the time the study was conducted and would have required informed consent. • Three of the authors of this article, Dr. Johan Courjon, Prof. Valérie Giordanengo, and Dr. Stéphane Honoré have contacted the journal to assert their opinion that they have concerns regarding the presentation and interpretation of results in this article and have stated they no longer wish to see their names associated with the article. • Author Prof. Valérie Giordanengo informed the journal that while the PCR tests administered in Nice were interpreted according to the recommendations of the national reference center, it is believed that those carried out in Marseille were not conducted using the same technique or not interpreted according to the same recommendations, which in her opinion would have resulted in a bias in the analysis of the data. This raises concerns as to whether the study was partially conducted counter to national guidelines at that time. The 17th author, Prof. Philippe Brouqui has attested that the PCR methodology was explained in reference 17 of the article. However, the article referred to by reference 17 describes several diagnostic approaches that were used (one PCR targeting the envelope protein only; another targeting the spike protein; and three commercially produced systems by QuantiNova, Biofire, and FTD). This reference does not clarify how the results were interpreted. It has also been noted during investigation of these concerns that only 76% (19/25) of patients were viral culture positive, resulting in uncertainty in the interpretation of PCR reports as has been raised by Prof. Giordanengo. As part of the investigation, the corresponding author was contacted and asked to provide an explanation for the above concerns. No response has been received within the deadline provided by the journal. Responses were received by the 3rd and 17th authors, Prof. Philippe Parola and Prof. Philippe Brouqui, respectively, and were reviewed as part of the investigation. These two authors, in addition to 1st author Dr. Philippe Gautret, 13th author Prof. Philippe Colson, and 15th author Prof. Bernard La Scola, disagreed with the retraction and dispute the grounds for it. Having followed due process and concluded the aforementioned investigation and based on the recommendation of Dr. Jim Gray acting in his capacity as independent Publishing Ethics Advisor, the co-owners of the journal (Elsevier and ISAC) have therefore taken the decision to retract the article.

Gautret P ，Lagier JC ，Parola P ，Hoang VT ，Meddeb L ，Mailhe M ，Doudier B ，Courjon J ，Giordanengo V ，Vieira VE ，Tissot Dupont H ，Honoré S ，Colson P ，Chabrière E ，La Scola B ，Rolain JM ，Brouqui P ，Raoult D ... -  《-》

Can a Liquid Biopsy Detect Circulating Tumor DNA With Low-passage Whole-genome Sequencing in Patients With a Sarcoma? A Pilot Evaluation.

A liquid biopsy is a test that evaluates the status of a disease by analyzing a sample of bodily fluid, most commonly blood. In recent years, there has been progress in the development and clinical application of liquid biopsy methods to identify blood-based, tumor-specific biomarkers for many cancer types. However, the implementation of these technologies to aid in the treatment of patients who have a sarcoma remains behind other fields of cancer medicine. For this study, we chose to evaluate a sarcoma liquid biopsy based on circulating tumor DNA (ctDNA). All human beings have normal cell-free DNA (cfDNA) circulating in the blood. In contrast with cfDNA, ctDNA is genetic material present in the blood stream that is derived from a tumor. ctDNA carries the unique genomic fingerprint of the tumor with changes that are not present in normal circulating cfDNA. A successful ctDNA liquid biopsy must be able to target these tumor-specific genetic alterations. For instance, epidermal growth factor receptor (EGFR) mutations are common in lung cancers, and ctDNA liquid biopsies are currently in clinical use to evaluate the status of disease in patients who have a lung cancer by detecting EGFR mutations in the blood. As opposed to many carcinomas, sarcomas do not have common recurrent mutations that could serve as the foundation to a ctDNA liquid biopsy. However, many sarcomas have structural changes to their chromosomes, including gains and losses of portions or entire chromosomes, known as copy number alterations (CNAs), that could serve as a target for a ctDNA liquid biopsy. Murine double minute 2 (MDM2) amplification in select lipomatous tumors or parosteal osteosarcoma is an example of a CNA due to the presence of extra copies of a segment of the long arm of chromosome 12. Since a majority of sarcomas demonstrate a complex karyotype with numerous CNAs, a blood-based liquid biopsy strategy that searches for these CNAs may be able to detect the presence of sarcoma ctDNA. Whole-genome sequencing (WGS) is a next-generation sequencing technique that evaluates the entire genome. The depth of coverage of WGS refers to how detailed the sequencing is, like higher versus lower power on a microscope. WGS can be performed with high-depth sequencing (that is, > 60×), which can detect individual point mutations, or low-depth sequencing (that is, 0.1× to 5×), referred to as low-passage whole-genome sequencing (LP-WGS), which may not detect individual mutations but can detect structural chromosomal changes including gains and losses (that is, CNAs). While similar strategies have shown favorable early results for specific sarcoma subtypes, LP-WGS has not been evaluated for applicability to the broader population of patients who have a sarcoma. Does an LP-WGS liquid biopsy evaluating for CNAs detect ctDNA in plasma samples from patients who have sarcomas representing a variety of histologic subtypes? This was a retrospective study conducted at a community-based, tertiary referral center. Nine paired (plasma and formalin-fixed paraffin-embedded [FFPE] tissue) and four unpaired (plasma) specimens from patients who had a sarcoma were obtained from a commercial biospecimen bank. Three control specimens from individuals who did not have cancer were also obtained. The paired and unpaired specimens from patients who had a sarcoma represented a variety of sarcoma histologic subtypes. cfDNA was extracted, amplified, and quantified. Libraries were prepared, and LP-WGS was performed using a NextSeq 500 next-generation sequencing machine at a low depth of sequencing coverage (∼1×). The ichorCNA bioinformatics algorithm, which was designed to detect CNAs from low-depth genomic sequencing data, was used to analyze the data. In contrast with the gold standard for diagnosis in the form of histopathologic analysis of a tissue sample, this test does not discriminate between sarcoma subtypes but detects the presence of tumor-derived CNAs within the ctDNA in the blood that should not be present in a patient who does not have cancer. The liquid biopsy was positive for the detection of cancer if the ichorCNA algorithm detected the presence of ctDNA. The algorithm was also used to quantitatively estimate the percent ctDNA within the cfDNA. The concentration of ctDNA was then calculated from the percent ctDNA relative to the total concentration of cfDNA. The CNAs of the paired FFPE tissue and plasma samples were graphically visualized using aCNViewer software. This LP-WGS liquid biopsy detected ctDNA in 9 of 13 of the plasma specimens from patients with a sarcoma. The other four samples from patients with a sarcoma and all serum specimens from patients without cancer had no detectable ctDNA. Of those 9 patients with positive liquid biopsy results, the percent ctDNA ranged from 6% to 11%, and calculated ctDNA quantities were 0.04 to 5.6 ng/mL, which are levels to be expected when ctDNA is detectable. In this small pilot study, we were able to detect sarcoma ctDNA with an LP-WGS liquid biopsy searching for CNAs in the plasma of most patients who had a sarcoma representing a variety of histologic subtypes. These results suggest that an LP-WGS liquid biopsy evaluating for CNAs to identify ctDNA may be more broadly applicable to the population of patients who have a sarcoma than previously reported in studies focusing on specific subtypes. Large prospective clinical trials that gather samples at multiple time points during the process of diagnosis, treatment, and surveillance will be needed to further assess whether this technique can be clinically useful. At our institution, we are in the process of developing a large prospective clinical trial for this purpose.

Anderson CJ ，Yang H ，Parsons J ，Ahrens WA ，Jagosky MH ，Hsu JH ，Patt JC ，Kneisl JS ，Steuerwald NM ... -  《-》

The effectiveness of school-based family asthma educational programs on the quality of life and number of asthma exacerbations of children aged five to 18 years diagnosed with asthma: a systematic review protocol.

Walter H ，Sadeque-Iqbal F ，Ulysse R ，Castillo D ，Fitzpatrick A ，Singleton J ... -  《-》