Decreased diversity of salivary microbiome in patients with stable decompensated cirrhosis.

BACKGROUND: In the setting of the oral-gut-liver axis, microbiome dysbiosis has been associated with decompensated cirrhosis progression. However, little is known on salivary microbiome profiles in stable decompensated patients. METHODS: We studied patients with stable decompensated cirrhosis (n =28) and matched healthy controls (n =26). There were five patients (17.8 %) with hepatocellular carcinoma (HCC). Microbiomes of the 54 salivary samples were profiled through next-generation sequencing of the 16S-rRNA region in bacteria. RESULTS: The two study groups (patients and controls) did not differ significantly concerning their baseline characteristics. The most abundant phyla were Firmicutes, Bacteroidetes, Proteobacteria, and Fusobacteria. Proposed dysbiosis ratio Firmicutes/Bacteroidetes was lower in patients than in controls (range: 0.05-2.54 vs. 0.28-2.18, p =0.4), showing no statistical significance. Phylum Deinococcus-Thermus was detected only in controls, while Phylum Planctomycetes only in patients. A-diversity analysis indicated low diversity of salivary microbiome in decompensated patients and patients with HCC, who presented specific discriminative taxa. On principal coordinate analysis (PCoA), the patients' and controls' salivary microbiomes clustered apart, suggesting differences in community composition (PERMANOVA test, p =0.008). Boruta wrapper algorithm selected the most representative genera to classify controls and patients (area under the curve =0.815). CONCLUSIONS: Patients with stable decompensated cirrhosis of various etiology and history of complications have decreased diversity of their salivary microbiome. PCoA and Boruta algorithm may represent useful tools to discriminate the salivary microbiome in patients with decompensation. Further studies are needed to establish the utility of salivary microbiome analysis, which is easier obtained than fecal, in decompensated cirrhosis. HIPPOKRATIA 2020, 24(4): 157-165.

'Distribution of Hepatitis C Virus genotypes in northern Greece in the last decade: descriptive analysis and clinical correlations'.

Hepatitis C virus (HCV) represents a major public health problem, while the identification of a HCV genotype is clinically very important for therapy prescription. The aim of the present study was to determine the HCV genotype distribution patients from northern Greece with HCV RNA positive viral load and to identify whether there is a shift in this distribution, during 2009-2017. The study was performed on 915 HCV positive patients and according to the results, genotype 3 was the most prevalent genotype (Ν = 395, 43.2%) followed by genotype 1 (Ν = 361, 39.5%). Regarding the gender of the patients, genotype 1 was mostly detected in women. Moreover, genotype 1 was associated with higher viral loads, while genotype 3 was most frequently detected in patients with a history of intravenous drug use. In conclusion, our results show that genotype 3 is the most prevalent genotype in Greece during the last decade as opposed to older epidemiological studies, likely due to intravenous drug use becoming the major source of infection.

Long-term effects of prolonged-release fampridine in cognitive function, fatigue, mood and quality of life of MS patients: The IGNITE study.

BACKGROUND: Studies have reported conflicting results regarding the potential benefit of prolonged release (PR) fampridine in other domains besides walking. Moreover, only a small number of studies have explored long- term effects of PR fampridine. The aim of this study was to assess cognitive function, quality of life, mood and fatigue in MS patients treated with fampridine after 6 and 12 months of treatment. METHODS: IGNITE was an observational, open label study. Subjects were examined with the timed 25-ft walk (T25FW) and the BICAMS battery and were asked to complete the Multiple Sclerosis Impact Scale (MSIS-29), Modified Fatigue Impact Scale (MFIS), Beck Depression Inventory-II (BDI-II) and MS International Quality-of-Life questionnaire (MUSIQOL) at baseline and at weeks 24 and 48. Patients were sub-grouped into responders (n:40) and non-responders (n:20) according to T25FW performance after 2 weeks on treatment. RESULTS: After 6 months, statistically significant improvement was observed on T25FW (p < .001), SDMT (p < .001) and MSIS29 (p < .001), for responders. After 1 year on treatment, statistically significant improvement was observed in T25FW (p < .001), MSIS29 (p = .004), SDMT (p < .001) and MUSIQOL (p = .03) for responders. There were no statistically significant improvements for the non-responders. CONCLUSIONS: PR Fampridine may have a beneficial effect on information processing speed though not on memory. Study data provide some evidence that fampridine treatment may reduce the impact of MS on daily activities and improve quality of life but has no effect on subjective fatigue and mood.

16S rRNA deep sequencing for the characterization of healthy human pharyngeal microbiome.

BACKGROUND: The recent advent of high-throughput sequencing methods enabled the study of the composition of the upper respiratory tract (URT) microbial ecosystem and its relationship with health and disease in immense detail. The aim of the present study was the characterization of the human pharyngeal microbiome of healthy individuals in Greece. MATERIALS AND METHODS: We obtained ten pharyngeal specimens from healthy volunteers, Greek resident, with Greek nationality, who were eligible to the selection criteria. The construction of DNA libraries was performed by using two primer sets that amplify selectively the corresponding hypervariable regions of the 16s region in bacteria (V2-V9). The Ion Torrent PGM platform was used for the performance of next-generation sequencing. RESULTS: In the study samples, twelve phyla were identified. The most abundant ones were Firmicutes, Proteobacteria, Bacteroidetes, followed by Actinobacteria and Fusobacteria. Seventy-nine families, 79 genera and 137 species were identified and characterized. Moreover, 17 unique differentially abundant families, 30 unique differentially abundant genera and 24 unique differentially abundant species were identified among healthy subgroups with adjusted p-values <0.05. At the genus level, Moraxella (Proteobacteria) and Gemella (Firmicutes) were detected with a statistical significance in non-smokers, while Bifidobacterium (Actinobacteria), Alloscardovia (Actinobacteria), Dialister (Firmicutes) and Filifactor (Firmicutes) were present mostly in smokers. CONCLUSIONS: The URT is colonized by a variety of protective and potentially pathogenic bacteria. This microbiome system is highly diverse and varies significantly between individuals. Geographic location and ethnicity are considered to be a strong determinants and factors affecting the diversity and abundance of the URT microbiome. Although some of the most abundant families are common irrespective of these factors, the dominance patterns are usually different between the study subjects and between the studies from other geographic locations. Unique differentially abundant families, genera and species were identified, and further studies are needed to elucidate their role. Further studies should focus on the investigation of the URT microbiome dynamics and the interaction with the host in health and disease. HIPPOKRATIA 2018, 22(1): 29-36.