12 research outputs found
Antenatal group B streptococcus detection in pregnant women: Culture or PCR?
Introduction: Group B streptococcus (GBS) is an important cause of neonatal infections. Maternal GBS colonization screening and intrapartum antimicrobial prophylaxis of colonized women can prevent neonatal diseases. The aim of this study was to assess the prevalence of GBS colonization in pregnant and non-pregnant women and to compare the performance of a polymerase chain reaction (PCR) assay with the established as gold standard technique, culture method, used for the detection of this microorganism. Methodology: Vaginal and rectal samples collected from 857 pregnant and 370 non-pregnant women were examined through cultures, while the samples collected from 452 pregnant women between 35 and 37 weeks of gestation were assayed by culture and PCR method targeting the cfb gene. Results: GBS colonization was present in both pregnant and non-pregnant women. The colonization rate was similar in non-pregnant and first trimester pregnant women and then increased from first to the third trimester of pregnancy. GBS cultures for vaginal and rectal samples were positive in 13.2% and 14.3% in non-pregnant women, while in pregnant women 13.2% and 13.7% in the first trimester, and 15.0% and 16.5% in the second trimester, respectively. In third trimester pregnant women, compared to culture method, PCR identified a significantly increased number of GBS positive vaginal (18.4% vs 22.6%, p = 0.0006) and rectal (18.1% vs 21.2%, p = 0.01) samples. Conclusions: GBS colonization rate was higher in the third trimester. PCR proved to be a rapid and useful GBS screening method allowing a shorter detection time, while identifying more colonized women than culture. © 2018 Gerolymatos et al
Natural-based indirubins display potent cytotoxicity toward wild-type and T315I-resistant leukemia cell lines
Drug resistance in chronic myelogenous leukemia (CML) requires the development of new CML chemotherapeutic drugs. Indirubin, a well-known mutikinase inhibitor, is the major active component of "Danggui Longhui Wan", a Chinese traditional medicine used for the treatment of CML symptoms. An in-house collection of indirubin derivatives was screened at 1 μM on wild-type and imatinib-resistant T315I mutant CML cells. Herein are reported that only 15 analogues of the natural 6-bromoindirubin displayed potent cytotoxicity in the submicromolar range. Kinase assays in vitro show that eight out of the 15 active molecules strongly inhibited both c-Src and Abl oncogenic kinases in the nanomolar range. Most importantly, these eight molecules blocked the activity of T315I mutant Abl kinase at the submicromolar level and with analogue 22 exhibiting inhibitory activity at the low nanomolar range. Docking calculations suggested that active indirubins might inhibit T315I Abl kinase through an unprecedented binding to both active and Src-like inactive conformations. Analogue 22 is the first derivative of a natural product identified as an inhibitor of wild-type and imatinib-resistant T315I mutant Abl kinases. © 2016 The American Chemical Society and American Society of Pharmacognosy
Natural-Based Indirubins Display Potent Cytotoxicity toward Wild-Type and T315I-Resistant Leukemia Cell Lines
Drug resistance in chronic myelogenous
leukemia (CML) requires
the development of new CML chemotherapeutic drugs. Indirubin, a well-known
mutikinase inhibitor, is the major active component of “Danggui
Longhui Wan”, a Chinese traditional medicine used for the treatment
of CML symptoms. An in-house collection of indirubin derivatives was
screened at 1 μM on wild-type and imatinib-resistant T315I mutant
CML cells. Herein are reported that only 15 analogues of the natural
6-bromoindirubin displayed potent cytotoxicity in the submicromolar
range. Kinase assays in vitro show that eight out of the 15 active
molecules strongly inhibited both <i>c</i>-Src and Abl oncogenic
kinases in the nanomolar range. Most importantly, these eight molecules
blocked the activity of T315I mutant Abl kinase at the submicromolar
level and with analogue <b>22</b> exhibiting inhibitory activity
at the low nanomolar range. Docking calculations suggested that active
indirubins might inhibit T315I Abl kinase through an unprecedented
binding to both active and Src-like inactive conformations. Analogue <b>22</b> is the first derivative of a natural product identified
as an inhibitor of wild-type and imatinib-resistant T315I mutant Abl
kinases
Molecular Epidemiology of SARS-CoV-2 in Greece Reveals Low Rates of Onward Virus Transmission after Lifting of Travel Restrictions Based on Risk Assessment during Summer 2020
The novel coronavirus severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) spread rapidly during the first months of 2020 and
continues to expand in multiple areas across the globe. Molecular
epidemiology has provided an added value to traditional public health
tools by identifying SARS-CoV-2 clusters or providing evidence that
clusters based on virus sequences and contact tracing are highly
concordant. Our aim was to infer the levels of virus importation and to
esti-mate the impact of public health measures related to travel
restrictions to local transmission in Greece. Our phylogenetic and
phylogeographic analyses included 389 full-genome SARS-CoV-2 sequences
collected during the first 7 months of the pandemic in Greece and a
random collection in five replicates of 3,000 sequences sampled
globally, as well as the best hits to our data set identified by BLAST.
Phylogenetic trees were reconstructed by the maximum likelihood method,
and the putative source of SARS-CoV-2 infections was inferred by
phylogeographic analysis. Phylogenetic analyses revealed the presence of
89 genetically distinct viruses identified as independent introductions
into Greece. The proportion of imported strains was 41%, 11.5%, and
8.8% during the three periods of sampling, namely, March (no travel
restrictions), April to June (strict travel restrictions), and July to
September (lifting of travel restrictions based on thorough risk
assessment), respectively. The results of phylogeographic analysis were
confirmed by a Bayesian approach. Our findings reveal low levels of
onward transmission from imported cases during summer and underscore the
importance of targeted public health measures that can increase the
safety of international travel during a pandemic.
IMPORTANCE Our study based on current state-of-the-art molecular
epidemiology methods suggests that virus screening and public health
measures after the lifting of travel restrictions prevented SARS-CoV-2
onward transmission from imported cases during summer 2020 in Greece.
These findings provide important data on the efficacy of targeted public
health measures and have important implications regarding the safety of
international travel during a pandemic. Our results can provide a
roadmap about prevention policy in the future regarding the reopening of
borders in the presence of differences in vaccination coverage, the
circulation of the virus, and the presence of newly emergent variants
across the globe