Emergence of Raoultella ornithinolytica in human infections from different hospitals in Ecuador with OXA-48-producing resistance.

Purpose: The purpose of this study was to highlight the clinical and molecular features of 13 Raoultella ornithinolytica strains isolated from clinical environments in Ecuador, and to perform comparative genomics with previously published genomes of Raoultella spp. As Raoultella is primarily found in environmental, clinical settings, we focused our work on identifying mechanisms of resistance that can provide this bacterium an advantage to establish and persist in hospital environments. Methods: We analyzed 13 strains of Raoultella ornithinolytica isolated from patients with healthcare associated infections (HAI) in three hospitals in Quito and one in Santo Domingo de Los Tsáchilas, Ecuador, between November 2017 and April 2018. These isolates were subjected to phenotypic antimicrobial susceptibility testing, end-point polymerase chain reaction (PCR) to detect the presence of carbapenemases and whole-genome sequencing. Results: Polymerase chain reaction revealed that seven isolates were positive isolates for blaOXA-48 and one for blaKPC-2 gene. Of the seven strains that presented the blaOXA-48 gene, six harbored it on an IncFII plasmid, one was inserted into the bacterial chromosome. The blaKPC gene was detected in an IncM2/IncR plasmid. From the bioinformatics analysis, nine genomes had the gene blaOXA-48, originating from Ecuador. Moreover, all R. ornithinolytica strains contained the ORN-1 gene, which confers resistance for ß-lactams, such as penicillins and cephalosporins. Comparative genome analysis of the strains showed that the pangenome of R. ornithinolytica is considered an open pangenome, with 27.77% of core genes, which could be explained by the fact that the antibiotic resistance genes in the ancestral reconstruction are relatively new, suggesting that this genome is constantly incorporating new genes. Conclusion: These results reveal the genome plasticity of R. ornithinolytica, particularly in acquiring antibiotic-resistance genes. The genomic surveillance and infectious control of these uncommon species are important since they may contribute to the burden of antimicrobial resistance and human health.

OXA-48 Carbapenemase in Klebsiella pneumoniae Sequence Type 307 in Ecuador.

Antibiotic resistance is on the rise, leading to an increase in morbidity and mortality due to infectious diseases. Klebsiella pneumoniae is a Gram-negative bacterium that causes bronchopneumonia, abscesses, urinary tract infection, osteomyelitis, and a wide variety of infections. The ubiquity of this microorganism confounds with the great increase in antibiotic resistance and have bred great concern worldwide. K. pneumoniae sequence type (ST) 307 is a widespread emerging clone associated with hospital-acquired infections, although sporadic community infections have also been reported. The aim of our study is to describe the first case of Klebsiella pneumoniae (ST) 307 harboring the blaOXA-48-like gene in Ecuador. We characterized a new plasmid that carry OXA-48 and could be the source of future outbreaks. The strain was recovered from a patient with cancer previously admitted in a Ukrainian hospital, suggesting that this mechanism of resistance could be imported. These findings highlight the importance of programs based on active molecular surveillance for the intercontinental spread of multidrug-resistant microorganisms with emergent carbapenemases.

Vascular responses to manual PC6 acupuncture in nonsmokers and smokers assessed by the second derivative of the finger photoplethysmogram waveform.

BACKGROUND: Smoking is reported to increase arterial stiffness. Indices obtained from the second derivative of digital volume pulse (SDDVP) waveform have been proposed to characterize vascular aging and arterial rigidity. PC6 (Neiguan) is a traditional acupoint in each forearm that has been shown to modify cardiovascular functioning. OBJECTIVE: To investigate the acute effects of manual needling with PC6 on SDDVP indices in healthy chronic smoker and nonsmoker subjects. SUBJECTS AND METHODS: Aging index (AI) was defined as (b - c - d - e)/a, B:A was calculated as the ratio of the absolute value for the height of the b wave (B) to that of the a wave (A), and D:A was calculated as the ratio of the absolute value for the height of the d wave (D) to that of the a wave (A). These indices derived of the wave components of SDDVP of healthy nonsmokers (n=40; 28.3+/-3.0 years old) vs. chronic smokers (n=30; 29.9+/-2.9 years old) were compared. The digital volume pulse (DVP) was obtained by measuring infrared light transmission through the finger. Of each subject, a DVP registration 20 minutes long was obtained. PC6 was stimulated unilaterally by manual needling for 5 minutes (1-6 minutes). SDDVP indices were compared in each subject in pre- vs. post-acupuncture periods (30 seconds vs. 18 minutes, respectively). RESULTS: At baseline, we found significant difference in B:A between nonsmokers and smokers. Comparing pre- vs. post-acupuncture periods, B:A and D:A did not show significant differences among nonsmokers, but B:A improved significantly in smokers and AI improved significantly in both nonsmokers and smokers. CONCLUSION: These findings suggest that manual needling with PC6 could revert some of the deleterious effects on vascular functioning produced by chronic cigarette smoking.

Assessment of the vascular effects of PC6 (Neiguan) using the second derivative of the finger photoplethysmogram in healthy and hypertensive subjects.

Indices obtained from the second derivative of the digital volume pulse waveform have been proposed to characterize vascular aging, arterial rigidity, and the effects of vasoactive drugs. The purpose of this study was to assess the effects of manual needling of PC6 on SD(DVP) indices in healthy and untreated hypertensive subjects. AI, B:A, and D:A indices, based on the height of the wave components of SD(DVP), in 40 healthy subjects and 25 untreated hypertensive subjects were compared. DVP was obtained by measuring infrared light transmission through the finger. For each subject, 20-min-long DVP registration was obtained. PC6 was stimulated unilaterally by manual needling for 5 min (1-6 min). In each subject, pre-acupuncture DVP indices were compared to those of during acupuncture (1 vs. 4 min) and post-acupuncture (1 vs. 18 min). In healthy subjects, AI was significantly improved when comparing the pre- to the post-acupuncture values. In hypertensive subjects, the SD(DVP) indices improved significantly as follows: the AI index when the value of pre-acupuncture comparing to that of during acupuncture and post-acupuncture values; B:A and D:A indices when the pre-comparing to post-acupuncture values. There were significant differences between healthy and hypertensive subjects in AI, B:A, and D:A at baseline and in B:A in the during acupuncture period; there were no significant differences at post-acupuncture. These results indicate that manual needling of PC6 produced acute effects on vascular pathophysiology. Moreover, PC6 needling produced changes in SD(DVP) indices related to both large artery stiffness and the reflected wave originating in small arteries.