The largest monkeypox virus (MPXV) outbreak described so far in non-endemic countries was identified in May 2022 (refs.
). In this study, shotgun metagenomics allowed the rapid reconstruction and ...phylogenomic characterization of the first MPXV outbreak genome sequences, showing that this MPXV belongs to clade 3 and that the outbreak most likely has a single origin. Although 2022 MPXV (lineage B.1) clustered with 2018-2019 cases linked to an endemic country, it segregates in a divergent phylogenetic branch, likely reflecting continuous accelerated evolution. An in-depth mutational analysis suggests the action of host APOBEC3 in viral evolution as well as signs of potential MPXV human adaptation in ongoing microevolution. Our findings also indicate that genome sequencing may provide resolution to track the spread and transmission of this presumably slow-evolving double-stranded DNA virus.
Up to 27 May 2022, Portugal has detected 96 confirmed cases of monkeypox. We describe 27 confirmed cases (median age: 33 years (range: 22-51); all males), with an earliest symptom onset date of 29 ...April. Almost all cases (n = 25) live in the Lisbon and Tagus Valley health region. Most cases were neither part of identified transmission chains, nor linked to travel or had contact with symptomatic persons or with animals, suggesting the possible previously undetected spread of monkeypox.
B cells play a role in pregnancy due to their humoral and regulatory activities. To our knowledge, different maturational stages (from transitional to memory) of circulating B cell subsets have not ...yet been characterized (cell quantification and phenotype identification) in healthy pregnant women. Thus, the objective of our study was to characterize these subsets (as well as regulatory B cells) from late pregnancy to post-partum and to compare them with the circulating B cells of non-pregnant women.
In all of the enrolled women, flow cytometry was used to characterize the circulating B cell subsets according to the expression of IgD and CD38 (Bm1-Bm5 classification system). Regulatory B cells were characterized based on the expression of surface antigens (CD24, CD27, and CD38) and the production of IL-10 after lipopolysaccharide stimulation.
Compared to the absolute counts of B cells in the non-pregnant women (n = 35), those in the pregnant women (n = 43) were significantly lower (p < 0.05) during the 3rd trimester of pregnancy and on delivery day (immediately after delivery). The percentages of these cells on delivery day and at post-partum were significantly lower than those in the non-pregnant women. In general, the absolute counts and percentages of the majority of the B cell subsets were significantly lower in the 3rd trimester of pregnancy and on delivery day than in the non-pregnant women. However, these counts and percentages did not differ significantly between the post-partum and the non-pregnant women. The most notable exceptions to the above were the percentages of naïve B cells (which were significantly higher in the 3rd trimester and on delivery day than in the non-pregnant women) and of CD24(hi)CD38(hi) regulatory B cells (which were significantly higher in the post-partum than in the non-pregnant women).
According to our study, the peripheral B cell compartment undergoes quantitative changes during normal late pregnancy and post-partum. Such findings may allow us to better understand immunomodulation during human pregnancy and provide evidence that could aid in the development of new strategies to diagnose and treat pregnancy-associated disturbances. Our findings could also be useful for studies of the mechanisms of maternal responses to vaccination and infection.
Bacterial biofilms are an important virulence factor with a vital role in evasion from the host immune system, colonization and infection. The aim of the present study was to evaluate in vitro the ...effects of three environmental factors (H+, glucose and human plasma) in biofilm formation, by carrier and invasive Streptococcus agalactiae strains of ST17 and ST19 sequence types, including DNase producers and non-producers. Bacteria ability to assemble biofilms was classified based on crystal violet assay. Biofilm formation was also monitored by scanning electron microscopy. Depending on the growth medium used, each bacterial isolate could fit in different biofilm production categories. Our data showed that optimal conditions for S. agalactiae biofilm assembly were reached after 48 h incubation at pH 7.6 in the presence of glucose and inactivated human plasma. In the presence of inactivated human plasma, the biofilm biomass of ST19 strains experienced a higher increase than ST17 strains. The composition of the extracellular polymeric matrix of the three strongest biofilm producers (all from ST17) was accessed by enzymatic digestion of mature biofilms and proteins were shown to be the predominant component. The detailed identification of the extracellular protein components should contribute to the development of new therapeutic strategies to fight S. agalactiae infections.
To elucidate the genome-based epidemiology and phylogenomics of azithromycin-resistant (MIC >2 mg/L) Neisseria gonorrhoeae strains collected in 2009-14 in Europe and clarify the azithromycin ...resistance mechanisms.
Seventy-five azithromycin-resistant (MIC 4 to >256 mg/L) N. gonorrhoeae isolates collected in 17 European countries during 2009-14 were examined using antimicrobial susceptibility testing and WGS.
Thirty-six N. gonorrhoeae multi-antigen sequence typing STs and five phylogenomic clades, including 4-22 isolates from several countries per clade, were identified. The azithromycin target mutation A2059G (Escherichia coli numbering) was found in all four alleles of the 23S rRNA gene in all isolates with high-level azithromycin resistance (n = 4; MIC ≥256 mg/L). The C2611T mutation was identified in two to four alleles of the 23S rRNA gene in the remaining 71 isolates. Mutations in mtrR and its promoter were identified in 43 isolates, comprising isolates within the whole azithromycin MIC range. No mutations associated with azithromycin resistance were found in the rplD gene or the rplV gene and none of the macrolide resistance-associated genes mef(A/E), ere(A), ere(B), erm(A), erm(B), erm(C) and erm(F) were identified in any isolate.
Clonal spread of relatively few N. gonorrhoeae strains accounts for the majority of the azithromycin resistance (MIC >2 mg/L) in Europe. The four isolates with high-level resistance to azithromycin (MIC ≥256 mg/L) were widely separated in the phylogenomic tree and did not belong to any of the main clades. The main azithromycin resistance mechanisms were the A2059G mutation (high-level resistance) and the C2611T mutation (low- and moderate-level resistance) in the 23S rRNA gene.
Regulatory T cells (Tregs) are critical immunomodulators during early pregnancy by preventing maternal T-cell activation against fetal cells. However, how populations of maternal Tregs vary during ...and after pregnancy in humans is still unclear. Therefore, we investigated Treg subsets in the peripheral blood of pregnant women from late pregnancy through the postpartum period. To accomplish this, the following circulating Treg subsets were analyzed in 43 healthy pregnant women and 35 nonpregnant women by flow cytometry during the third trimester, on the day of delivery, and postpartum: CD4
CD25
, CD4
CD25
Foxp3
, and CD4
CD25
CD127
. Additionally, the expression levels of the transcription factor Foxp3 in CD4
CD25
Treg were analyzed. We have found that CD4
CD25
Treg subset significantly decreased in the pregnant women on the day of delivery relative to the third trimester ( P < .05), and that all Treg subsets significantly increased postpartum compared to the third trimester and the day of delivery ( P < .05). Moreover, the Foxp3 expression ratios within the CD4
CD25
Treg subset decreased during pregnancy and until delivery compared to those measured in the nonpregnant women and significantly increased postpartum compared to the third trimester and the day of delivery ( P < .05). Thus, despite their established role in offering immunoprotection to the fetus in early pregnancy, the number of circulating Tregs also varies from late pregnancy to the postpartum period. Our results offer an explanation for the possible effects of pregnancy on the clinical outcomes of some autoimmune diseases during the postpartum period.
Background
In autosomal dominant polycystic kidney disease (ADPKD) it is frequently found a reduction in urinary citrate of unknown origin. It has been suggested that it could be a marker of acid ...retention in chronic kidney disease. Our aim was to compare urinary citrate in ADPKD with other nephropathies and to show its relation with serum bicarbonate.
Methods
We determined urinary citrate in patients with several nephropathies and varied renal function. We included 291 patients, 119 with glomerular diseases, 116 with ADPKD, 21 with other nephropathies, and 35 patients with normal renal function.
Results
Urinary citrate was higher in women and in patients with normal renal function. ADPKD patients showed similar values of urinary citrate to patients with glomerular diseases and with other nephropathies. We observed a progressive reduction in urinary citrate with renal impairment, in a comparable way among patients with ADPKD and glomerular diseases. We did not observe a relationship with serum bicarbonate. Serum uric acid levels were significantly higher in patients with glomerular diseases than in ADPKD patients, even after correction with the degree of renal function.
Conclusions
Hypocitraturia is not specific of ADPKD but it is also present in all tested nephropathies and is related with renal impairment and not with serum bicarbonate. It could be interesting to study urinary citrate as a marker of renal function and as a prognostic factor.
Outbreak of monkeypox in an STD clinic in Lisbon Caldeira, Margarida; Fernandes, Cândida; Neves, José ...
Journal of the European Academy of Dermatology and Venereology,
February 2023, 2023-02-00, 20230201, Letnik:
37, Številka:
2
Journal Article