Impact of malnutrition on postoperative delirium development after on pump coronary artery bypass grafting

BACKGROUND & AIMS

Even though malnutrition is frequently observed in cardiac population outcome data after cardiac surgery in malnourished patients is very rare. No thorough research was done concerning the impact of malnutrition on neuropsychological outcomes after cardiac surgery. The aim of our study was to analyze the incidence of postoperative delirium development in malnourished patients undergoing on pump bypass grafting.

METHODS

We performed a cohort study of adults admitted to Vilnius University Hospital Santariskiu Clinics for elective coronary artery bypass grafting. The nutritional status of the patients was assessed by Nutritional Risk Screening 2002 (NRS-2002) questionnaire the day before surgery. Patients were considered as having no risk of malnutrition when NRS-2002 score was less than 3 and at risk of malnutrition when NRS-2002 score was ≥3. During ICU stay patients were screened for postoperative delirium development using the CAM-ICU method. and divided into two groups: delirium and non delirium. The statistical analysis was preformed to evaluate the differences between the two independent groups. The logistic regression model was used to evaluate the potential preoperative and intraoperative risk factors of postoperative delirium.

RESULTS

Ninety-nine patients were enrolled in the study. Preoperative risk of malnutrition was detected in 24 % (n = 24) of the patients. The incidence of early postoperative delirium in overall study population was 8.0 % (n = 8). The incidence of the patients at risk of malnutrition was significantly higher in the delirium group (5 (62.5 %) vs 19 (20.9 %), p <0.0191). In multivariate logistic regression analysis risk of malnutrition defined by NRS 2002 was an independent preoperative and intraoperative risk factor of postoperative delirium after coronary artery bypass grafting (OR: 6.316, 95 % CI: 1.384-28.819 p = 0.0173).

CONCLUSIONS

Preoperative malnutrition is common in patients undergoing elective coronary artery bypass grafting. Nutrition deprivation is associated with early postoperative delirium after on pump coronary artery bypass grafting.

Zanamivir Diminishes Lung Damage in Influenza A Virus-infected Mice by Inhibiting Nitric Oxide Production

BACKGROUND/AIM

Severe pulmonary influenza A virus (IAV) infection causes lung inflammation and expression of inducible nitric oxide synthase (iNOS), leading to overproduction of nitric oxide (NO). We studied whether zanamivir reduces pulmonary inflammation through inhibition of NO production in mice.

MATERIALS AND METHODS

We treated IAV-infected mice daily with intranasal zanamivir. Controls were infected and either placebo-treated or untreated, or not infected and placebo-treated. Mice were weighed daily. After euthanasia on day 3, lungs were excised and bronchoalveolar lavage was performed and fluid nitrite concentration was determined. Lungs were analyzed microscopically. iNOS and IAV RNA levels in lungs were assessed using quantitative reverse transcription-polymerase chain reaction (RT-qPCR).

RESULTS

Mice undergoing zanamivir treatment had less weight loss, viral replication, and lung damage, as well as significant reductions of local NO and iNOS mRNA synthesis (p<0.05).

CONCLUSION

Zanamivir is associated with an anti-inflammatory effect mediated through inhibition of NO production in IAV-infected mice.

Streptococcus mutans biofilm inhibition using antisense oligonucleotide to glucosyltransferases B and C

Background. Biofilm formation by Streptococcus mutans bacteria on teeth leads to dental caries, which still remains one of the most prevalent human diseases strongly related to increase of dietary sucrose consumption in modern society. In the biofilm, sucrose is metabolized by S. mutans to acids causing tooth decay. S. mutans also produces glucosyltransferases (Gtfs) for synthesis of sticky glucan polymers from sucrose that provides matrix for biofilm formation on teeth. For reducing biofilm build-up, one preventive measure could be blocking of Gtf synthesis. The aim of this study was to test antisense phosphorothioate oligodeoxyribonucleotide (PS-ODN) targeting simultaneously S. mutans gtfB and gtfC mRNAs in order to inhibit biofilm formation in vitro. Materials and methods. S. mutans bacteria were grown anaerobically on glass slides inserted vertically in 24-well cell culture plates containing Todd Hewitt broth with sucrose under exposure to antisense or missense PS-ODNs at the final concentration of 10 μM. Untreated bacteria served as controls. After 24 h of incubation, glass slides were removed, air-dried and further used for the quantitative evaluation of the streptococci biofilm applying an optical profilometry technique. Results. It was revealed that antisense PS-ODN considerably reduced the most critical biofilm surface roughness parameter Sa (average difference between the peak hight and valleys) inhibiting the biofilm development by 46% and 77% in comparison to untreated (p = 0.06) and missense PS-ODN-treated bacteria (p < 0.05), respectively. Conclusions. The results demonstrate that antisense PS-ODN considerably decreases streptococci-induced biofilm development on glass slides, and might therefore significantly suppress dental biofilm formation through simultaneous inactivation of S. mutans gtfB and gtfC mRNAs.

Antimicrobial Resistance and the Prevalence of the Panton-Valentine Leukocidin Gene among Clinical Isolates of Staphylococcus aureus in Lithuania

This study aimed to determine resistance to antimicrobials of Staphylococcus aureus strains isolated from clinical specimens in Lithuanian hospitals and to identify the genes conferring resistance and virulence. The study was carried out from June 2019 to September 2021. S. aureus strains were isolated from skin, soft tissues, blood, lower respiratory tract, urine and other specimens. Antibiotic susceptibility testing was performed using the disc diffusion method according to EUCAST guidelines. All isolates were analyzed for detection of the ermA, ermC, mecA, mecC, tetK, tetM, and lukF-PV genes by multiplex real-time PCR. The 16S rRNA coding sequence was applied as an internal PCR control. Altogether, 745 S. aureus strains were analyzed. Antimicrobial susceptibility testing revealed that all isolates were susceptible to rifampin and vancomycin. Of the 745 strains, 94.8% were susceptible to tetracycline, 94.5% to clindamycin, and 88.3% to erythromycin. The lowest susceptibility rate was found for penicillin (25.8%). Six percent of the tested strains were methicillin-resistant S. aureus (MRSA). The majority of methicillin-resistant strains were isolated from skin and soft tissues (73.3%), with a smaller portion isolated from blood (17.8%) and respiratory tract (8.9%). The ermC gene was detected in 41.1% of erythromycin-resistant S. aureus strains, whereas ermA was detected in 32.2% of erythromycin-resistant S. aureus strains. 69.2% of tetracycline-resistant S. aureus strains had tetK gene, and 28.2% had tetM gene. 7.3% of S. aureus isolates harbored lukF-PV gene. The frequency of the pvl gene detection was significantly higher in MRSA isolates than in methicillin-susceptible S. aureus isolates (p < 0.0001).

Detection of multidrug-resistance in Mycobacterium tuberculosis by phenotype- and molecular-based assays

BACKGROUND

The whole-genome sequencing (WGS) is becoming an increasingly effective tool for rapid and accurate detection of drug resistance in Mycobacterium tuberculosis complex (MTBC). This approach, however, has still been poorly evaluated on strains from Central and Eastern European countries. The purpose of this study was to assess the performance of WGS against conventional drug susceptibility testing (DST) for the detection of multi-drug resistant (MDR) phenotypes among MTBC clinical strains from Poland and Lithuania.

METHODS

The study included 208 MTBC strains (130 MDR; 78 drug susceptible), recovered from as many tuberculosis patients in Lithuania and Poland between 2018 and 2021. Resistance to rifampicin (RIF) and isoniazid (INH) was assessed by Critical Concentration (CC) and Minimum Inhibitory Concentration (MIC) DST as well as molecular-based techniques, including line-probe assay (LPA) and WGS. The analysis of WGS results was performed using bioinformatic pipeline- and software-based tools.

RESULTS

The results obtained with the CC DST were more congruent with those by LPA compared to pipeline-based WGS. Software-based tools showed excellent concordance with pipeline-based analysis in prediction of RIF/INH resistance. The RIF-resistant strains demonstrated a relatively homogenous MIC distribution with the mode at the highest tested MIC value. The most frequent RIF-resistance conferring mutation was rpoB S450L. The mode MIC for INH was two-fold higher among double katG and inhA mutants than among single katG mutants. The overall rate of discordant results between all methods was calculated at 5.3%. Three strains had discordant results by both genotypic methods (LPA and pipeline-based WGS), one strain by LPA only, three strains by MIC DST, two strains by both MIC DST and pipeline-based WGS, and the remaining two strains showed discordant results with all three methods, compared to CC DST.

CONCLUSIONS

Considering MIC DST results, current CCs of the first-line anti-TB drugs might be inappropriately high and may need to be revised. Both molecular methods demonstrated 100% specificity, while pipeline-based WGS had slightly lower sensitivity for RIF and INH than LPA, compared to CC DST.

Reducing dental plaque formation and caries development. A review of current methods and implications for novel pharmaceuticals

Dental caries is an oral disease, which has a high worldwide prevalence despite the availability of various prophylactic means, including the daily use of fluoride toothpastes, water fluoridation, dental sealants, oral health educational programs and various antiseptic mouth-rinses. One important reason for this is uncontrolled increase in consumption of foods containing considerable sucrose concentration, especially among children. Sucrose is easily metabolized by oral bacteria (mostly streptococci) to acids and, subsequently, causing tooth decay or dental caries. In the oral ecosystem, streptococci principally reside on tooth surfaces forming biofilm. Important structural and binding materials of biofilm are glucan polymers synthesized by several isoforms of glucosyltransferase enzyme present in certain species of oral bacteria, including mutans group streptococci - Streptococcus mutans and Streptococcus sobrinus, which preferably colonize humans. Thus, there is a constant need to develop the methods and chemotherapeutics for improving oral health care and decreasing teeth decay through the suppression of cariogenic biofilm formation in the oral cavity. The aim of this paper was to review literature related to the pathogenesis of dental caries as well as currently existing and experimental pharmaceutical substances used for prevention of this process.