PARP-3 and APLF function together to accelerate nonhomologous end joining

PARP-3 is a member of the ADP-ribosyl transferase superfamily of unknown function. We show that PARP-3 is stimulated by DNA double-strand breaks (DSBs) in vitro and functions in the same pathway as the poly (ADP-ribose)-binding protein APLF to accelerate chromosomal DNA DSB repair. We implicate PARP-3 in the accumulation of APLF at DSBs and demonstrate that APLF promotes the retention of XRCC4/DNA ligase IV complex in chromatin, suggesting that PARP-3 and APLF accelerate DNA ligation during nonhomologous end-joining (NHEJ). Consistent with this, we show that class switch recombination in Aplf−/− B cells is biased toward microhomology-mediated end-joining, a pathway that operates in the absence of XRCC4/DNA ligase IV, and that the requirement for PARP-3 and APLF for NHEJ is circumvented by overexpression of XRCC4/DNA ligase IV. These data identify molecular roles for PARP-3 and APLF in chromosomal DNA double-strand break repair reactions

Endosymbiosis in trypanosomatid protozoa: the bacterium division is controlled during the host cell cycle

Mutualism is defined as a beneficial relationship for the associated partners and usually assumes that the symbiont number is controlled. Some trypanosomatid protozoa co-evolve with a bacterial symbiont that divides in coordination with the host in a way that results in its equal distribution between daughter cells. The mechanism that controls this synchrony is largely unknown, and its comprehension might provide clues to understand how eukaryotic cells evolved when acquiring symbionts that later became organelles. Here, we approached this question by studying the effects of inhibitors that affect the host exclusively in two symbiont-bearing trypanosomatids, Strigomonas culicis and Angomonas deanei. We found that inhibiting host protein synthesis using cycloheximide or host DNA replication using aphidicolin did not affect the duplication of bacterial DNA. Although the bacteria had autonomy to duplicate their DNA when host protein synthesis was blocked by cycloheximide, they could not complete cytokinesis. Aphidicolin promoted the inhibition of the trypanosomatid cell cycle in the G1/S phase, leading to symbiont filamentation in S. culicis but not in A. deanei. Treatment with camptothecin blocked the host protozoa cell cycle in the G2 phase and induced the formation of filamentous symbionts in both species. Oryzalin, which affects host microtubule polymerization, blocked trypanosomatid mitosis and abrogated symbiont division. Our results indicate that host factors produced during the cell division cycle are essential for symbiont segregation and may control the bacterial cell number

A human 5'-tyrosyl DNA phosphodiesterase that repairs topoisomerase-mediated DNA damage

Topoisomerases regulate DNA topology and are fundamental to many aspects of chromosome metabolism1, 2. Their activity involves the transient cleavage of DNA, which, if it occurs near sites of endogenous DNA damage or in the presence of topoisomerase poisons, can result in abortive topoisomerase-induced DNA strand breaks3, 4, 5. These breaks feature covalent linkage of the enzyme to the DNA termini by a 3'- or 5'-phosphotyrosyl bond and are implicated in hereditary human disease6, 7, 8, chromosomal instability and cancer4, 9, and underlie the clinical efficacy of an important class of anti-tumour poisons3, 9, 10. The importance of liberating DNA termini from trapped topoisomerase is illustrated by the progressive neurodegenerative disease observed in individuals containing a mutation in tyrosyl-DNA phosphodiesterase1 (TDP1), an enzyme that cleaves 3'-phosphotyrosyl bonds6, 7, 8. However, a complementary human enzyme that cleaves 5'-phosphotyrosyl bonds has not been reported, despite the effect of DNA double-strand breaks containing such termini on chromosome instability and cancer6, 7, 8. Here we identify such an enzyme in human cells and show that this activity efficiently restores 5'-phosphate termini at DNA double-strand breaks in preparation for DNA ligation. This enzyme, TTRAP, is a member of the Mg2+/Mn2+-dependent family of phosphodiesterases. Cellular depletion of TTRAP results in increased susceptibility and sensitivity to topoisomerase-II-induced DNA double-strand breaks. TTRAP is, to our knowledge, the first human 5'-tyrosyl DNA phosphodiesterase to be identified, and we suggest that this enzyme is denoted tyrosyl DNA phosphodiesterase-2 (TDP2)

Bedaquiline-pretomanid-moxifloxacin-pyrazinamide for drug-sensitive and drug-resistant pulmonary tuberculosis treatment: a phase 2c, open-label, multicentre, partially randomised controlled trial

Background The current tuberculosis (TB) drug development pipeline is being re-populated with candidates, including nitroimidazoles such as pretomanid, that exhibit a potential to shorten TB therapy by exerting a bactericidal effect on non-replicating bacilli. Based on results from preclinical and early clinical studies, a four-drug combination of bedaquiline, pretomanid, moxifloxacin, and pyrazinamide (BPaMZ) regimen was identified with treatment-shortening potential for both drug-susceptible (DS) and drug-resistant (DR) TB. This trial aimed to determine the safety and efficacy of BPaMZ. We compared 4 months of BPaMZ to the standard 6 months of isoniazid, rifampicin, pyrazinamide, and ethambutol (HRZE) in DS-TB. 6 months of BPaMZ was assessed in DR-TB. Methods SimpliciTB was a partially randomised, phase 2c, open-label, clinical trial, recruiting participants at 26 sites in eight countries. Participants aged 18 years or older with pulmonary TB who were sputum smear positive for acid-fast bacilli were eligible for enrolment. Participants with DS-TB had Mycobacterium tuberculosis with sensitivity to rifampicin and isoniazid. Participants with DR-TB had M tuberculosis with resistance to rifampicin, isoniazid, or both. Participants with DS-TB were randomly allocated in a 1:1 ratio, stratified by HIV status and cavitation on chest radiograph, using balanced block randomisation with a fixed block size of four. The primary efficacy endpoint was time to sputum culture-negative status by 8 weeks; the key secondary endpoint was unfavourable outcome at week 52. A non-inferiority margin of 12% was chosen for the key secondary outcome. Safety and tolerability outcomes are presented as descriptive analyses. The efficacy analysis population contained patients who received at least one dose of medication and who had efficacy data available and had no major protocol violations. The safety population contained patients who received at least one dose of medication. This study is registered with ClinicalTrials.gov (NCT03338621) and is completed. Findings Between July 30, 2018, and March 2, 2020, 455 participants were enrolled and received at least one dose of study treatment. 324 (71%) participants were male and 131 (29%) participants were female. 303 participants with DS-TB were randomly assigned to 4 months of BPaMZ (n=150) or HRZE (n=153). In a modified intention-to-treat (mITT) analysis, by week 8, 122 (84%) of 145 and 70 (47%) of 148 participants were culture-negative on 4 months of BPaMZ and HRZE, respectively, with a hazard ratio for earlier negative status of 2·93 (95% CI 2·17–3·96; p<0·0001). Median time to negative culture (TTN) was 6 weeks (IQR 4–8) on 4 months of BPaMZ and 11 weeks (6–12) on HRZE. 86% of participants with DR-TB receiving 6 months of BPaMZ (n=152) reached culture-negative status by week 8, with a median TTN of 5 weeks (IQR 3–7). At week 52, 120 (83%) of 144, 134 (93%) of 144, and 111 (83%) of 133 on 4 months of BPaMZ, HRZE, and 6 months of BPaMZ had favourable outcomes, respectively. Despite bacteriological efficacy, 4 months of BPaMZ did not meet the non-inferiority margin for the key secondary endpoint in the pre-defined mITT population due to higher withdrawal rates for adverse hepatic events. Non-inferiority was demonstrated in the per-protocol population confirming the effect of withdrawals with 4 months of BPaMZ. At least one liver-related treatment-emergent adverse effect (TEAE) occurred among 45 (30%) participants on 4 months of BPaMZ, 38 (25%) on HRZE, and 33 (22%) on 6 months of BPaMZ. Serious liver-related TEAEs were reported by 20 participants overall; 11 (7%) among those on 4 months of BPaMZ, one (1%) on HRZE, and eight (5%) on 6 months of BPaMZ. The most common reasons for discontinuation of trial treatment were hepatotoxicity (ten participants [2%]), increased hepatic enzymes (nine participants [2%]), QTcF prolongation (three participants [1%]), and hypersensitivity (two participants [<1%]).Interpretation For DS-TB, BPaMZ successfully met the primary efficacy endpoint of sputum culture conversion. The regimen did not meet the key secondary efficacy endpoint due to adverse events resulting in treatment withdrawal. Our study demonstrated the potential for treatment-shortening efficacy of the BPaMZ regimen for DS-TB and DR-TB, providing clinical validation of a murine model widely used to identify such regimens. It also highlights that novel, treatment-shortening TB treatment regimens require an acceptable toxicity and tolerability profile with minimal monitoring in low-resource and high-burden settings. The increased risk of unpredictable severe hepatic adverse events with 4 months of BPaMZ would be a considerable obstacle to implementation of this regimen in settings with high burdens of TB with limited infrastructure for close surveillance of liver biochemistry. Future research should focus on improving the preclinical and early clinical detection and mitigation of safety issues together and further efforts to optimise shorter treatments

International Social Survey Programme: Social Relations and Support Systems - ISSP 2001

Soziale Beziehungen und Hilfeleistungen. Themen: Geschwisterzahl; Häufigkeit von persönlichen (Besuche,Treffen) und nicht-persönlichen Kontakten (Telefon, Brief, Fax oderE-Mail) mit den Eltern, Geschwistern und eigenen Kindern; Zeit für dieAnreise zur Mutter, Häufigkeit der Kontakte zu Verwandten (Onkeln undTanten, Cousins, Schwiegereltern, Schwägern oder Schwägerinnen, Nichtenund Neffen, Paten); Anzahl enger Freunde aus dem Kollegenkreis, aus derNachbarschaft und allgemein; Geschlecht des besten Freundes;Kontakthäufigkeit zum besten Freund; aktive Einbindung in eine Partei,einen Verband, eine Kirche oder religiöse Vereinigung, einenSportverein, eine karitative Vereinigung oder einerNachbarschaftsgruppe; erster und zweiter Ansprechpartner fürHilfeleistungen im Haushalt, bei Geldproblemen und Niedergeschlagenheit(Depression); Häufigkeit eigener Hilfeleistung in den Bereichen:Haushalt, Geldverleihen, Niedergeschlagenheit und bei derArbeitsplatzsuche; Informationsquelle bei der Suche nach dergegenwärtigen Arbeitsstelle; Wichtigkeit von Charaktereigenschaftenenger Freunde: Intelligenz, Hilfsbereitschaft, Verständnis undangenehme Gesellschaft (Skala); Einstellung zur moralischenVerpflichtung erwachsener Kinder zur Pflege ihrer Eltern, zum GrundsatzFamilie geht vor, zum Solidarprinzip, zur Entwicklung vonFreundschaften zum eigenen Vorteil (Skala); Einstellung zu einerstaatlichen Verantwortung zur Sicherung der Kinderbetreuung und einesangemessenen Lebensstandards für alte Menschen persönlicheGlückseinschätzung; Gefühl der Überforderung durch Familie, Verwandteoder Freunde; Vertrauen in Mitmenschen (Skala); Wohndauer am Wohnort(Einzugsjahr); Gefühl eigener politischer Wirksamkeit auf lokaleAngelegenheiten und auf die Politik allgemein; Häufigkeit politischerDiskussionen im Freundeskreis. Zusätzlich verkodet wurde: Ortsgröße; ethnische Zugehörigkeit; Erhebungsmethode. Demographie: Land; Anzahl Kinder unter 18 Jahren und über 18 Jahren; Geschlecht; Alter; Familienstand; Zusammenleben mit einem Partner; absolvierte Schuljahre; Bildungsniveau; Berufstätigkeit des Befragten und des Partners (ISCO88); Vorgesetztenstatus; Beschäftigung im öffentlichen Dienst; Selbständigenstatus und Betriebsgröße; Wochenarbeitszeit; Konfession; Kirchgangshäufigkeit; Selbsteinschätzung der Schichtzugehörigkeit; Gewerkschaftsmitgliedschaft; politische Selbsteinschätzung auf einem Links-rechts-Kontinuum; Haushaltsgröße; Haushaltszusammensetzung; Urbanisierungsgrad; Ortsgröße; Interviewmethode

International Social Survey Programme: Citizenship - ISSP 2004

Citizen and state. Topics: Qualities of a good citizen; attitude toward the right ofpublic meetings for religious extremists, people who want to overthrowthe government by force, or people prejudiced against any racial orethnic group; social and political participation; memberships;importance of different people`s rights in democracy (scale);estimation of political influence possibilities (political efficacy);likeliness of counter-action against an unjust law and expected chanceof serious attention to people`s demand; interest in politics; personaltrust in politicians and people; political discussions with friends;opinion leadership in politics; national sovereignty and attitude tointernational organisations; attitude to the action of politicalparties; real policy choice between parties; attitude toward areferendum; level of honesty and fairness in the last nationalelection; commitment to serve people and likeliness to correct ownmistakes in public service; corruption in public service; functioningof democracy at present, in the past and in the future; frequencies ofmedia use; respect for people and tolerance in case of disagreement;self-description of the habitation (residence); voter participation;voting behaviour (recall). Demography: Sex; age; marital-status; steady life-partner; education;current employment status; hours worked weekly; occupation (ISCO 1988);working for private or public sector or selfemployed; if selfemployed:number of employees; supervisor function; trade union membership;current employment status (ISCO 1988); earnings; family income;household size; household composition; party affiliation; participationin last election; religious denomination; attendance of religiousservices; self-placement on a top-bottom scale; region; size ofcommunity; type of community: urban-rural area; ethnicity, nationalityand family-origin. Additionally coded: administrative mode of data-collection