BackgroundInfertility is estimated to affect approximately 9–30% of reproductive-aged couples. Several conditions involving one or both partners may contribute to infertility. The aim of this study is to evaluate the role of asymptomatic genital tract infections in the outcome of In Vitro Fertilization (IVF) in couples with infertility.MethodsA total of 285 infertile couples were enrolled in the study. Vaginal/endocervical swabs and semen samples were collected and subjected to microbiological analysis. Spermiograms were carried out on semen specimens, and lactobacilli were quantified in vaginal swabs. Data were associated with IVF results and analysed by using non parametric tests and multivariate analysis.ResultsMicrobiological analysis showed that 46.3% of couples presented with an asymptomatic genital tract infection. Spermiogram results showed a significantly diminished motility of sperm cells in samples positive to microbiological testing compared to negative specimens. Enterococcus faecalis was the most prevalent species (11.6%) in positive semen samples and was found to negatively affect both sperm morphology (p = 0.026) and motility (p = 0.003). Analysis of genital swabs from females showed that the presence of E. faecalis (p<0.0001), Escherichia coli (p = 0.0123), Streptococcus agalactiae (p<0.0001), and Gardnerella vaginalis (p = 0.0003) was significantly associated to reduced levels of vaginal lactobacilli. Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02).ConclusionsThe results show the negative impact of E. faecalis on sperm quality and the association of definite bacterial pathogens with reduced levels of vaginal lactobacilli. The presence of E. faecalis and/or U. urealyticum and/or M. hominis in genital samples of infertile couples is predictive for a negative outcome of IVF.

Aims:  The three main aims of the study were the assessment of the genetic relationship between a deviating Erwinia amylovora strain isolated from Amelanchier sp. (Maloideae) grown in Canada and other strains from Maloideae and Rosoideae, the investigation of the variability of the PstI fragment of the pEA29 plasmid using restriction fragment length polymorphism (RFLP) analysis and the determination of the number of short‐sequence DNA repeats (SSR) by DNA sequence analysis in representative strains. Methods and Results:  Ninety‐three strains obtained from 12 plant genera and different geographical locations were examined by repetitive‐sequences PCR using Enterobacterial Repetitive Intergenic Consensus, BOX and Repetitive Extragenic Palindromic primer sets. Upon the unweighted pair group method with arithmetic mean analysis, a deviating strain from Amelanchier sp. was analysed using amplified ribosomal DNA restriction analysis (ARDRA) analysis and the sequencing of the 16S rDNA gene. This strain showed 99% similarity to other E. amylovora strains in the 16S gene and the same banding pattern with ARDRA. The RFLP analysis of pEA29 plasmid using MspI and Sau3A restriction enzymes showed a higher variability than that previously observed and no clear‐cut grouping of the strains was possible. The number of SSR units reiterated two to 12 times. The strains obtained from pear orchards showing for the first time symptoms of fire blight had a low number of SSR units. Conclusions:  The strains from Maloideae exhibit a wider genetic variability than previously thought. The RFLP analysis of a fragment of the pEA29 plasmid would not seem a reliable method for typing E. amylovora strains. A low number of SSR units was observed with first epidemics of fire blight. Significance and Impact of the Study:  The current detection techniques are mainly based on the genetic similarities observed within the strains from the cultivated tree‐fruit crops. For a more reliable detection of the fire blight pathogen also in wild and ornamentals Rosaceous plants the genetic features of deviating E. amylovora strains have to be studied in detail.

A total of 73 Erwinia amylovora strains obtained from 13 Maloideae host species and from Rubus spp., and isolated from different geographic areas, were assessed using RFLP and DNA sequencing analysis of the 3 ′ hrp N gene and /or of a fragment of 1341 bp of the dsp A/E region. An Erwinia pyrifoliae strain, used as outgroup, was checked in the same way. For the three strains isolated from Rubus spp. and for one strain from Amelanchier sp., RFLP analysis of the hrp N gene using the Rsa I enzyme yielded a PCR product 60 bp smaller than that of all the other strains. Sequence analysis of the gene revealed this was due to the absence of a 60 bp fragment in the noncoding region downstream of the gene. The strain PD 2915, isolated from Amelanchier sp. grown in Canada, showed five same-sense substitutions and one missense substitution at position 868 of the hrp N gene, converting aspartic acid into asparagine. Also, restriction analysis of a fragment of 613 bp of the dsp A/E region with Cfo I revealed an RFLP pattern suitable for differentiating the E. amylovora strains isolated from Rubus spp. and Amelanchier sp. from all the others. In the dsp A/E coding region, the four strains showed 13 -14 missense point mutations, in some cases yielding drastic amino acid substitutions. In addition, partial sequencing of the dsp A/E region of PD 2915 from Amelanchier sp. indicated a higher similarity to E. amylovora strains isolated from Rubus spp. than towards strains from other Maloideae hosts. The E. pyrifoliae strain showed 23 single nucleotide substitutions along the hrp N gene and 88% of nucleotide identity with E. amylovora strains in the portion of dsp A/E region. Artificial inoculations on immature pear fruits and young shoots of Maloideae and Ruboideae showed a restricted pathogenicity for the strains from Rubus and Amelanchier , with the latter inciting blight symptoms only on Amelanchier .

Bacterial drug resistance is one of the major challenges to present and future human health, as the continuous selection of multidrug resistant bacteria poses at serious risk the possibility to treat infectious diseases in the near future. One of the infection at higher risk to become incurable is tuberculosis, due to the few drugs available in the market against Mycobacterium tuberculosis. Drug resistance in this species is usually due to point mutations in the drug target or in proteins required to activate prodrugs. However, another interesting and underexplored aspect of bacterial physiology with important impact on drug susceptibility is represented by the changes in transcriptional regulation following drug exposure. The main regulators involved in this phenomenon in M. tuberculosis are the sigma factors, and regulators belonging to the WhiB, GntR, XRE, Mar and TetR families. Better understanding the impact of these regulators in survival to drug treatment might contribute to identify new drug targets and/or to design new strategies of intervention.

The whole-genome sequences of Mycobacterium chimera strains 850 and 852, which were isolated from two different water samples obtained from a heater-cooler unit at Siena Hospital (Italy), were determined by combining Nanopore and Illumina technologies. Both strain 850 and strain 852 genomes consist of a circular chromosome and five plasmids, with sizes of 6,275,686 bp and 6,453,144 bp, respectively.

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