The investigation of antibacterial activity of hyperlight fluid fusion subcellular essential complex.

INTRODUCTION: This study aimed to investigate the possibility of applying the hyperlight fluid fusion essential complex in dental plaque control, and to evaluate the effectiveness of new and modern agents used for the prevention and early treatment of gingivitis. METHODOLOGY: The study included 60 subjects randomly divided into two groups. The control group was assigned to 0.12% chlorhexidine (CHX) mouth rinse, whereas the test group used a solution based on hyper-harmonized hydroxylated fullerene water complex (3HFWC), twice daily for 2 weeks. The plaque, gingivitis and bleeding scores were evaluated and recorded. Collected plaque samples were seeded on blood agar and incubated aerobically at a temperature of 37 °C for 24-48 hours. In order to isolate anaerobic bacteria, samples were seeded on Schaedler Agar and incubated anaerobically at 37 °C for seven days. Serial dilutions in saline from 101 - 106 were made, and grown colonies were counted and identified using the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) system. RESULTS: The reduction in the number of bacteria was significant in both control and test groups. The reduction was greater in the control group compared to the experimental group, but without statistically significant difference. CONCLUSIONS: 3HFWC treatment causes significant reduction in the number of dental plaque microorganisms. Since 3HFWC solution exhibited a bacteriostatic effect similar to chlorhexidine it could be an adequate addition to solution of a growing problem in prevention and early treatment of gingivitis and periodontitis.

Epidemiological Predictors of Positive SARS-CoV-2 Polymerase Chain Reaction Test in Three Cohorts: Hospitalized Patients, Healthcare Workers, and Military Population, Serbia, 2020.

(1) Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resulting coronavirus disease 2019 (COVID-19) has caused a fast-moving pandemic. Diagnostic testing, aimed to identify patients infected with SARS-CoV-2, plays a key role in controlling the COVID-19 pandemic in different populations. (2) Methods: This retrospective cohort study aimed to investigate predictors associated with positive polymerase chain reaction (PCR) SARS-CoV-2 test results in hospitalized patients, healthcare workers (HCWs), and military personnel (MP) during 2020, before the widespread availability of COVID-19 vaccines. Persons with a positive test result were compared with persons with a negative test result in three cohorts during the study period. (3) Results: A total of 6912 respondents were tested, and 1334 (19.3%) of them had positive PCR SARS-CoV-2 test results. Contact with a known COVID-19 case within 14 days (p < 0.001; OR: 1.48; 95% CI: 1.25-1.76), fever (p < 0.001; OR: 3.66; 95% CI: 3.04-4.41), cough (p < 0.001; OR: 1.91; 95% CI: 1.59-2.30), headache (p = 0.028; OR: 1.24; 95% CI: 1.02-1.50), and myalgia/arthralgia (p < 0.001; OR: 1.99; 95% CI: 1.65-2.42) were independently associated with positive PCR SARS-CoV-2 test results in the cohort of MP. Furthermore, fever (p < 0.001; OR: 2.75; 95% CI: 1.83-4.13), cough (p < 0.001; OR: 2.04; 95% CI: 1.32-3.13), headache (p = 0.008; OR: 1.76; 95% CI: 1.15-2.68), and myalgia/arthralgia (p = 0.039; OR: 1.58; 95% CI: 1.02-2.45) were independently associated with positive PCR SARS-CoV-2 test results in the cohort of HCWs. Moreover, independent predictors of positive PCR SARS-CoV-2 test results in hospitalized patients were contact with a known COVID-19 case within 14 days (p < 0.001; OR: 2.56; 95% CI: 1.71-3.83), fever (p < 0.001; OR: 1.89; 95% CI: 1.38-2.59), pneumonia (p = 0.041; OR: 1.45; 95% CI: 1.01-2.09), and neurological diseases (p = 0.009; OR: 0.375; 95% CI: 0.18-0.78). (4) Conclusions: According to data gathered from cohorts of hospitalized patients, HCWs, and MP, before the widespread availability of COVID-19 vaccines in Serbia, we can conclude that predictors of positive PCR SARS-CoV-2 test results in MP and HCWs were similar. Accurate estimates of COVID-19 in different population groups are important for health authorities.

Inhibitory effects of propolis and essential oils on oral bacteria.

INTRODUCTION: Propolis is a natural composite balsam. In the past decade, propolis has been extensively investigated as an adjuvant for the treatment of periodontitis. This study aimed to investigate antimicrobial activities of propolis solutions and plant essential oils against some oral cariogenic (Streptococcus mutans, Streptococcus mitis, Streptococcus sanguis, Lactobacillus acidophilus) and periodontopathic bacteria (Actinomyces odontolyticus, Eikenella corrodens, Fusobacterium nucleatum). METHODOLOGY: Determination of the minimum inhibitory concentration (MIC): The antimicrobial activity of propolis and essential oils was investigated by the agar dilution method. Serial dilutions of essential oils were prepared in plates, and the assay plates were estimated to contain 100, 50, 25 and 12.5 µg/mL of active essential oils. Dilutions for propolis were 50, 25, 12.5 and 6.3 µg/mL of active propolis solutions. RESULTS: Propolis solutions dissolved in benzene, diethyl ether and methyl chloride, demonstrated equal effectiveness against all investigated oral bacteria (MIC=12.5 µg/mL). Propolis solution dissolved in acetone displayed MIC of 6.3 µg/mL only for Lactobacillus acidophilus. At the MIC of 12.5 µg/mL, essential oils of Salvia officinalis and Satureja kitaibelii were effective against Streptococcus mutans and Porphyromonas gingivalis, respectively. For the latter, the MIC value of Salvia officinalis was twice higher. CONCLUSIONS: The results indicate that propolis and plant essential oils appear to be a promising source of antimicrobial agents that may prevent dental caries and other oral infectious diseases.

Shiga toxin-producing Escherichia coli O171:H25 strain isolated from a patient with haemolytic uraemic syndrome.

Shiga toxin-producing Escherichia coli (STEC) strains of O157:H7 serotype are a predominant cause of haemolytic uraemic syndrome (HUS) worldwide, but strains of non-O157 serotypes can also be associated with serious disease. Some of them are associated with outbreaks of HUS, others with sporadic cases of HUS, and some with diarrhoea but not with outbreaks or HUS. A large number of STEC serotypes isolated from ruminants and foods have never been associated with human disease. In this study we characterize a STEC strain belonging to serotype O171:H25 that is responsible for a case of HUS. This strain has a single Shiga toxin gene encoding Stx2 toxin, and hlyA gene, but is eae-negative.

[Foodborne disease outbreak among soldiers in Nis garrison associated with the consumption of coleslaw].

AIM/BACKGROUND: Large outbreaks of foodborne diseases are always focused by the general public who expect experts to rapidly explain both the causes of the disease and its growth. This article presents the results of the investigation of an outbreak of foodborne disease that has attracted much of the electronic and written media attention. METHODS: The data on food items consumed by intoxicated and healthy soldiers were obtained by the adapted questionnaire during a field investigation performed on November 3-4, 2005. On the same occasion other relevant data were also collected. For microbiological investigations stool samples from the ill persons were collected, as well as food specimen and swabs from the working surfaces and utensils in the kichen where the food had been prepared. RESULTS: In the outbreak of foodborne disease, which started on November 2, 2005, and terminated on the next day, 103 ill soldiers were registered in 7 units scattered over 4 locations in the garrison of Nis. The attack rate varied in the affected units from 33 to 338 per thousand, with the mean value of 109.7 per thousand. The clinical course of the disease was predominantly light including vomiting, diarrhea and fever as the most frequent signs of illness. All the affected soldiers were hospitalized, treated with symptomatic therapy, and discharged fully recovered. By comparing dishes that had been consumed by the ill and the healthy persons before the beginning of the outbreak, the greatest statistical significance (p < 0.0001), and the only significant relative risk (RR = 3.43) were related to the consumption of the coleslaw served for lunch on November 1, 2005. In addition, two control groups with the total of 151 persons who had not consumed the coleslaws were identified no one of them was affected. An microbiological investigation did not reveal any bacterial enteropathogens. CONCLUSION: In the described foodborne disease outbreak a causative agent was not identified although coleslaw was the way of transmission probably secondarily contaminated by the improper hygiene practice during its processing.

[Epidemiological importance of humans and domestic animals as reservoirs of verocytotoxin-producing Escherichia coli].

BACKGROUND/AIM: A "new" pathogenic agent, verocytotoxin--producing Escherichia coli (VTEC) emerged in the last 20 years, causing an increased number of sporadic cases, as well as of outbreaks of diarrhoeal diseases. Humans and animals can be infected with VTEC, but their epidemiological importance as a reservoir of this agent is not quite clear, especially in the Balkan region. Therefore, the aim of this study was to investigate the frequency of isolation of VTEC from the intestinal tract of humans and animals and to determine the serogroups of the isolated strains. METHODS: A total of, 3 401 stool samples from humans and 2 660 samples from five different species of domestic animals were tested for the presence of this pathogen. RESULTS: VTEC was isolated from 20 (0.6%) humans stools and from 431 (16.2%) animal fecal samples (p < 0.001). Only 15 (3.3%) VTEC strains belonged to human infection-associated serogroups (O26, O55, O111, O128 and O157), designated as enterohaemorrhagic E. coli (EHEC). The most known serogroup-O157 was identified in 6 (1.3%) of the isolated VTEC strains; of them, 1 (5%) was of human origin and 5 (1.2%) were animal strains. CONCLUSION: This study revealed that domestic animals were a more important reservoir of VTEC than humans, and that the isolated VTEC strains rarely belonged to O157, as well as to other EHEC serogroups that might explain rare sporadic cases and the absence of epidemic occurrence of diarrhoeal diseases caused by VTEC in this geographic region.

[First documented case of enterocolitis in Yugoslavia caused by enterohemorrhagic Escherichia coli O157]. / Prvi dokazani slucaj enterokolitisa u Jugoslaviji uzrokovan enterohemoragijskom eserihijom koli O157.

A 'new' group of pathogenic agents, enterohemorrhagic Escherichia coli (EHEC) (particularly the strains of O157 serogroup), emerged in the last 20 years, causing an increased number of sporadic and epidemic diarrhoeal diseases with hemorrhagic enterocolitis as a most common clinical manifestation of the infection. As a consequence of the absorption and cytotoxic effect of the main virulence factor of these bacteria--verotoxin (shiga-toxin), in about 10% of the affected persons extraintestinal complications, most frequently hemolytic-uremic syndrome (HUS), occurred 7-14 days after an episode of diarrhoeal disease. The first case of hemorrhagic enterocolitis with the documented EHEC O157 infection in Yugoslavia is presented in this paper. Considering the existing expansion trend of these carriers, practitioners should be aware of them in case of the occurrence of diarrhoeal disease, (particularly hemorrhagic enterocolitis), and keep these patients under control during the reconvalescence period because of potential development of extraintestinal complications, such as HUS.