Effects of intermittent fasting on periodontal inflammation and subgingival microbiota.

BACKGROUND: Studies on the impact of intermittent fasting on periodontal health are still scarce. Thus, this study evaluated the effects of long-term intermittent fasting on periodontal health and the subgingival microbiota. METHODS: This pilot study was part of a nonrandomized controlled trial. Overweight/obese participants (n = 14) entered an intermittent fasting program, specifically the 5:2 diet, in which they restricted caloric intake to about a quarter of the normal total daily caloric expenditure for two nonconsecutive days/week. Subjects underwent a thorough clinical and laboratory examination, including an assessment of their periodontal condition, at baseline and 6 months after starting the diet. Additionally, subgingival microbiota was assessed by 16S rRNA gene sequencing. RESULTS: After 6 months of intermittent fasting, weight, body mass index, C-reactive protein, hemoglobin A1c (HbA1c), and the cholesterol profile improved significantly (p < 0.05). Moreover, significant reductions were observed in bleeding on probing (p = 0.01) and the presence of shallow periodontal pockets after fasting (p < 0.001), while no significant change was seen in plaque index (p = 0.14). While we did not observe significant changes in α- or ß-diversity of the subgingival microbiota related to dietary intervention (p > 0.05), significant differences were seen in the abundances of several taxa among individuals exhibiting ≥60% reduction (good responders) in probing pocket depth of 4-5 mm compared to those with <60% reduction (bad responders). CONCLUSION: Intermittent fasting decreased systemic and periodontal inflammation. Although the subgingival microbiota was unaltered by this intervention, apparent taxonomic variability was observed between good and bad responders.

[Periodontitis - an often neglected risk factor for several other diseases]. / Parodontit ­ en ofta förbisedd riskfaktor för en rad sjukdomar.

Periodontitis is a chronic inflammatory disease that degrades dental supporting tissues, including the alveolar bone. The global prevalence is 19%, in Sweden it is 11%. Left untreated, periodontitis can cause loss of teeth. The initial clinical manifestations of periodontitis usually start between 35 and 45 years of age. The underlying pathological mechanism is an aberrant inflammatory response to the bacteria colonizing the gingival crevice. Periodontitis has been associated with several other diseases, most prominently diabetes. The relation between periodontitis and diabetes is bidirectional in the sense that diabetes increases the risk for periodontitis and vice versa. Periodontitis also increases the risk for cardiovascular disease and cancer.

[Diabetes and periodontitis - common, important but often neglected]. / Diabetes och parodontit ­ viktig aspekt av diabetesvården.

Diabetes and periodontitis are two global epidemics. There is a two-way relationship between diabetes and periodontitis. Diabetes increases the risk of periodontitis and periodontitis increases the risk for deteriorating glucose levels, having undetected diabetes, and for future diabetes. A recent Cochrane report summarized that there is moderate-certainty evidence that periodontal treatment improves glycaemic control in people with both periodontitis and diabetes. The recent PAROKRANK study found that undetected dysglycaemia was independently associated to both myocardial infarction and to periodontitis. To increase awareness of oral health in people with diabetes this article summarizes recent evidence.

Cathodoluminescence investigations of dark-line defects in platelet-based InGaN nano-LED structures.

We have investigated the optical properties of heterostructured InGaN platelets aiming at red emission, intended for use as nano-scaled light-emitting diodes. The focus is on the presence of non-radiative emission in the form of dark line defects. We have performed the study using hyperspectral cathodoluminescence imaging. The platelets were grown on a template consisting of InGaN pyramids, flattened by chemical mechanical polishing. These templates are defect free, whereas the dark line defects are introduced in the lower barrier and tend to propagate through all the subsequent layers, as revealed by the imaging of different layers in the structure. We conclude that the dark line defects are caused by stacking mismatch boundaries introduced by multiple seeding and step bunching at the edges of the as-polished, dome shaped templates. To avoid these defects, we suggest that the starting material must be flat rather than dome shaped.

Periodontitis in young individuals: Important factors for disease progression.

AIM: To investigate the progression of periodontitis in young individuals and identify factors that contribute to progression rate and whether periodontitis stage and grade have an impact on disease progression. MATERIALS AND METHODS: This retrospective cohort study was based on patients younger than 36 years at two periodontal clinics between 2003 and 2009. At least 10 years later, a clinical and radiographic examination was performed on 215 patients. The marginal bone loss between baseline and follow-up for the tooth with the most severe bone loss at follow-up was estimated by radiographic measurements. Linear regression analysis was used to investigate the influence of potential risk indicators on periodontitis progression. RESULTS: Most patients (83%) were classified as periodontitis stage III at baseline. At follow-up, 70% of these patients remained in stage III. The frequency of patients with grade C decreased from 79% to 17% at follow-up. The median (Q25%; Q75%) of the longitudinal marginal bone loss was 0.5 mm (0.0; 2.0). High bleeding on probing (BOP) index at baseline, smoking and interruption of periodontal treatment were found to significantly increase longitudinal bone loss. CONCLUSIONS: High levels of BOP at baseline, smoking and interruption of periodontal treatment increased the risk of marginal bone loss. The stage and grade at baseline had no significant impact on disease progression.

Associations between the Bacterial Composition of Farm Bulk Milk and the Microbiota in the Resulting Swedish Long-Ripened Cheese.

The maturation of a traditional Swedish long-ripened cheese has shown increasing variation in recent years and the ripening time is now generally longer than in the past. While the cheese is reliant on non-starter lactic acid bacteria for the development of its characteristic flavour, we hypothesised that the observed changes could be due to variations in the microbiota composition and number of bacteria in the raw milk used for production of the cheese. To evaluate associations between microbiota in the raw milk and the resulting cheese, three clusters of commercial farms were created to increase variation in the microbiota of dairy silo milk used for cheese production. Cheese production was performed in three periods over one year. Within each period, milk from the three farm clusters was collected separately and transported to the cheese production facility. Following pasteurisation, the milk was processed into the granular-eyed cheese and matured at a dedicated cheese-ripening facility. For each cheese batch, farm bulk and dairy silo milk samples, a starter culture, early process samples and cheese samples from different stages of maturation (7-20 months) were collected and their microbiota characterised using 16S rRNA amplicon sequencing. The microbiota in the farm bulk milk differed significantly between periods and clusters. Differences in microbiota in dairy silo milk were observed between periods, but not between farm clusters, while the cheese microbiota differed between periods and clusters. The top 13 amplicon sequence variants were dominant in early process samples and the resulting cheese, making up at least 93.3% of the relative abundance (RA). Lactococcus was the dominant genus in the early process samples and, together with Leuconostoc, also dominated in the cheese samples. Contradicting expectations, the RA of the aroma-producing genus Lactobacillus was low in cheese during ripening and there was an unexpected dominance of starter lactic acid bacteria even at the later stages of cheese ripening. To identify factors behind the recent variations in ripening time of this cheese, future studies should address the effects of process variables and the dairy environment.

The Resolution of Periodontal Inflammation Promotes Changes in Cytokine Expression in the Intestine and Gingival Tissues of Aged Rats with DSS-Induced Colitis.

Our research aimed to explore how resolving periodontal inflammation impacts cytokine expression in the colons of aged Wistar rats. Research studies involving animals have been conducted to investigate the two-way relationship between periodontitis and inflammatory bowel disease (IBD), where chronic inflammation in either the mouth or intestines can negatively affect the other. We allocated seventeen male Wistar rats aged between 8 and 11 months to one of four groups: (1) ligature-induced periodontitis (LIP) without the resolution of periodontal inflammation (RPI) (LIP; n = 4), (2) LIP + RPI (n = 4), (3) LIP + dextran-sulphate-sodium-induced colitis (DIC) without RPI (n = 4), and LIP + DIC + RPI (n = 5). We performed histopathological and immunological analyses on periodontal and intestinal tissues and analysed cytokine expressions using a Rat Cytokine 23-Plex Immunoassay. Our findings showed that animals with and without DIC who underwent RPI showed significantly lower levels of IL-2, IL-4, IL-5, IL-10, IL-13, IL-17, IL-18, and TNF-α in the intestine compared to those without treatment. The RPI effectively reduced the number of inflammatory cells in the lamina propria and restored the epithelial barrier in the intestine in animals with DIC. The resolution of periodontal inflammation significantly reduced the levels of pro-inflammatory cytokines and chemokines in the intestines of aged rats with and without DSS-induced colitis.

Higher expression of Th1/Th2-related cytokines in the intestine of Wistar rats with ligature-induced periodontitis.

OBJECTIVE: This study aimed to investigate the impact of ligature-induced periodontitis (LIP) on histopathological and immunological outcomes in the colon of Wistar rats. BACKGROUND: It has been repeatedly shown that inflammatory bowel disease (IBD) patients are at higher risk of developing periodontitis and presenting worse oral health than non-IBD patients. However, whether the chronic inflammatory process around teeth contributes to the pathophysiology of IBD needs to be further explored. MATERIALS AND METHODS: Thirteen Wistar rats were allocated into LIP (n = 7) and controls (n = 6). Half of the colon was processed for histopathological analyses and immunohistochemical (CD45); the other half was homogenized for immunological analyses. Periodontal destruction was confirmed by measuring the distance from the cementum-enamel junction to the mandible's apical position of the mesial interproximal bone. The immunological analyses were performed with the Bio-Plex Th1/Th2 assay. RESULTS: There was a significantly higher interproximal bone loss in LIP compared to controls. The LIP group showed a moderate infiltrate of inflammatory cells, predominantly mononucleated cells in the intestinal tissues. There was significantly higher expression of GM-CSF, IFN-γ, IL-1α, IL-1ß, IL-2, IL-4, IL-5, IL-10, IL-12 (p70), IL-13, and TNF-α in the intestinal tissues of LIP group compared to controls. CONCLUSION: Ligature-induced periodontitis was associated with an overexpression of Th1/Th2-related cytokines in the colon of Wistar rats.

Colitis induced by dextran sulphate sodium causes histopathological and immunological changes in the periodontal tissues of Wistar rats.

OBJECTIVE: This study investigated the impact of colitis induced by dextran sulphate sodium (DSS)-induced colitis (DIC) on histopathological and immunological outcomes in the periodontal tissues of Wistar rats. BACKGROUND: Inflammatory bowel diseases (IBD) and periodontitis have been reported to present a bidirectional relationship. However, the inflammatory pathway that connects both diseases needs further investigation. MATERIAL AND METHODS: Twenty-five male Wistar rats were allocated in four groups: unilateral ligature-induced periodontitis for 14 days: LIP (n = 7); dextran sulphate sodium-induced colitis only: DIC (n = 6); DIC + LIP (n = 6) and controls (n = 6). Digital images were obtained from the histological sections. In order to assess the attachment loss (AL), the linear distance between the cementoenamel junction (CEJ) and the alveolar bone crest was measured on the mesial root using histological photomicrography's ImageJ software. Immunological analyses of gingival tissues and plasma were performed by Bio-Plex Th1/Th2 Assay. RESULTS: The DIC group showed inflammatory cells extending to the periodontal connective tissues, which contained significantly elevated expressions of IL-1α, IL-1ß, IL-2, IL-6, IL-12, IL-13, GM-CSF, IFN-γ and TNF-α compared to controls. There was no significant difference in bone loss between controls and DIC. There were no significant histopathological differences between DIC + LIP and LIP. However, DIC + LIP presented a significantly lower IL-2 and IL-5 than the LIP group. There was no bone loss difference between LIP+DIC and LIP groups. DIC + LIP group presented significantly higher levels of GM-CSF in plasma. CONCLUSION: DSS-induced colitis was associated with an overexpression of Th1/Th2- related cytokines in the gingival tissue.

Association of peptidoglycan recognition protein 1 to post-myocardial infarction and periodontal inflammation: A subgroup report from the PAROKRANK (Periodontal Disease and the Relation to Myocardial Infarction) study.

BACKGROUND: Peptidoglycan recognition protein 1 (PGLYRP1) is an antimicrobial and proinflammatory innate immunity protein activated during infections. We aimed to investigate whether PGYLRP1 and associated molecules of the immune response in saliva is a cumulative outcome result of both MI and periodontal inflammation. METHODS AND RESULTS: Two hundred patients with MI and another 200 matched non-MI controls were included. A full-mouthexamination was conducted to assess periodontal inflammation and collection of stimulated saliva was performed 6 to 10 weeks after the first MI. PGLYRP1, triggering receptor expressed on myeloid cells 1 (TREM-1), interleukin-1 beta (IL-1ß) were analyzed by ELISA. Matrix metalloproteinase (MMP)-8 levels were determined by IFMA. Compared to controls, MI patients showed higher salivary PGLYRP1, but not TREM-1 levels. The difference in PGLYRP1 levels remained after adjustment for covariates. In MI patients, the PGLYRP1 levels positively correlated with BOP and PPD 4 to 5 mm. Among non-MI subjects, the levels of PGLYRP1 correlated positively and significantly with BOP and total PPD. Salivary PGLYRP1 concentrations also showed strong positive correlations with levels of TREM-1, IL-1ß and MMP-8. In multivariate linear regression analysis, in MI patients, BOP and former smokingstatus displayed an association with salivary PGLYRP1 concentration. CONCLUSION: MI patients showed higher salivary PGLYRP1 levels than healthy controls, also after adjusting for smoking, sex, age and periodontal health status. Salivary levels of PGLYRP1 may reflect the overall inflammatory burden to chronic bacterial exposure, possibly underpinning the observed associations between periodontitis and exposure with MI.

Milking system and premilking routines have a strong effect on the microbial community in bulk tank milk.

In this study, we investigated the variation in the microbial community present in bulk tank milk samples and the potential effect of different farm management factors. Bulk tank milk samples were collected repeatedly over one year from 42 farms located in northern Sweden. Total and thermoresistant bacteria counts and 16S rRNA gene-based amplicon sequencing were used to characterize microbial community composition. The microbial community was in general heterogeneous both within and between different farms and the community composition in the bulk tank milk was commonly dominated by Pseudomonas, Acinetobacter, Streptococcus, unclassified Peptostreptococcaceae, and Staphylococcus. Principal component analysis including farm factor variables and microbial taxa data revealed that the microbial community in milk was affected by type of milking system. Milk from farms using an automatic (robot) milking system (AMS) and loose housing showed different microbial community composition compared with milk from tiestall farms. A discriminant analysis model revealed that this difference was dependent on several microbial taxa. Among farms using an automatic milking system, there were further differences in the microbial community composition depending on the brand of the milking robot used. On tiestall farms, routines for teat preparation and cleaning of the milking equipment affected the microbial community composition in milk. Total bacteria count (TBC) in milk differed between the farm types, and TBC were higher on AMS than tiestall farms (log 4.05 vs. log 3.79 TBC/mL for AMS and tiestalls, respectively). Among tiestall farms, milk from farms using a chemical agent in connection to teat preparation and a more frequent use of acid to clean the milking equipment had lower TBC in milk, than milk from farms using water for teat preparation and a less frequent use of acid to clean the milking equipment (log 3.68 vs. 4.02 TBC/mL). There were no significant differences in the number of thermoresistant bacteria between farm types. The evaluated factors explained only a small proportion of total variation in the microbiota data, however, despite this, the study highlights the effect of routines associated with teat preparation and cleaning of the milking equipment on raw milk microbiota, irrespective of type of milking system used.

Designing satisfying service encounters: website versus store touchpoints.

This study investigated how touchpoints moderate the antecedents of customer satisfaction with service encounters by comparing online and in-store encounters. Construal level theory was used within the Touchpoint, Context, Qualities (TCQ) Framework (De Keyser et al., 2020) to integrate a comprehensive model of how touchpoints-websites or stores-influence the magnitude of customer responses to qualities of service encounters. A hierarchical linear model (HLM) was estimated using survey data describing the service encounters of 2.4 million customers with a global retailer. Online customers weighed cognitive and behavioral qualities more heavily than in-store customers, whereas they weighed emotional and sensorial qualities less heavily. Moreover, random effects in the HLM model indicated that each country and store would have unique clientele effects for specific qualities. Since each firm has limited resources, this research offers guidance on key qualities in designing satisfying service encounters for each touchpoint and how qualities should be standardized and customized in global omnichannel environments. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11747-021-00808-9.

Periodontitis is associated to increased systemic inflammation in postmyocardial infarction patients.

OBJECTIVE: Periodontitis has been independently associated to cardiovascular disease. However, the biological mechanisms underlying such association are still partially unknown. Thus, this study aimed to discover immunological clues accounting for the increased risk of myocardial infarction (MI) in patients having periodontitis. METHODS: We included 100 patients with a first MI, 50 with and 50 without severe periodontitis, and 100 age-matched, sex-matched and area-matched controls from the Periodontitis and Its Relation to Coronary Artery Disease Study. Participants underwent comprehensive clinical and laboratory examinations 6-10 weeks after the MI and plasma expression of 92 inflammation-related markers was assessed through proximity extension assay. RESULTS: Patients who had an MI displayed altered expression of CCL19, TNFRSF9 and LAP TGF-ß1 in comparison with controls. TNFRSF9 correlated significantly with the amount of alveolar bone loss. MI patients with deep periodontal pockets showed increased white cell count and higher expression of FGF-21, HGF, OSM, CCL20 and IL-18R1 than patients without. White cell count correlated significantly with four of these proteins. CONCLUSIONS: Collectively, our results indicate molecular markers that could be responsible for the increased systemic inflammatory activity in patients with MI with periodontitis.

Composition and properties of bovine milk: A study from dairy farms in northern Sweden; Part I. Effect of dairy farming system.

This study was part of a larger project that aimed to understand the causes for increasing variation in cheese ripening in a cheese-producing region in northern Sweden. The influence of different on-farm factors on raw milk composition and properties was investigated and is described in this paper, whereas the monthly variation in the milk quality traits during 1 yr is described in our companion paper. The dairy farming systems on a total of 42 dairy farms were characterized through a questionnaire and farm visits. Milk from farm tanks was sampled monthly over 1 yr and analyzed for quality attributes important for cheese making. On applying principal component analyses to evaluate the variation in on-farm factors, different types of farms were distinguished. Farms with loose housing and automatic milking system (AMS) or milking parlor had a higher number of lactating cows, and predominantly Swedish Holstein (SH) breed. Farms associated with tiestalls had a lower number of lactating cows and breeds other than SH. Applying principal component analyses to study the variation in composition and properties of tank milk samples from farms revealed a tendency for the formation of 2 clusters: milk from farms with AMS or a milking parlor, and milk from farms with tiestall milking. The interaction between the milking system, housing system, and breed probably contributed to this grouping. Other factors that were used in the characterization of the farming systems only showed a minor influence on raw milk quality. Despite the interaction, milk from tiestall farms with various cow breeds had higher concentrations (g/100 g of milk) of fat (4.74) and protein (3.63), and lower lactose concentrations (4.67) than milk from farms with predominantly SH cows and AMS (4.32, 3.47, and 4.74 g/100 g of milk, respectively) or a milking parlor (4.47, 3.54, and 4.79 g/100 g of milk, respectively). Higher somatic cell count (195 × 103/mL) and lower free fatty acid concentration (0.75 mmol/100 g of fat) were observed in milk from farms with AMS than in milk from tiestall systems (150 × 103/mL and 0.83 mmol/100 g of fat, respectively). Type of farm influenced milk gel strength, with milk from farms with predominantly SH cows showing the lowest gel strength (65.0 Pa), but not a longer rennet coagulation time. Effects of dairy farming system (e.g., dominant breed, milking system, housing, and herd size) on milk quality attributes indicate a need for further studies to evaluate the in-depth effects of farm-related factors on milk quality attributes.

Composition and properties of bovine milk: A study from dairy farms in northern Sweden; Part II. Effect of monthly variation.

This study investigated the influence of monthly variation on the composition and properties of raw farm milk collected as part of a full-scale cheese-making trial in a region in northern Sweden. In our companion paper, the contribution of on-farm factors to the variation in milk quality attributes is described. In total, 42 dairy farms were recruited for the study, and farm milk samples were collected monthly over 1 yr and characterized for quality attributes of importance for cheese making. Principal component analysis suggested that milk samples collected during the outdoor period (June-September) were different from milk samples collected during the indoor period. Despite the interaction with the milking system, the results showed that fat and protein concentrations were lower in milk collected during May through August, and lactose concentration was higher in milk collected during April through July than for the other months. Concentrations of free fatty acids were generally low, with the highest value (0.86 mmol/100 g of fat) observed in February and the lowest (0.70 mmol/100 g of fat) observed in June. Plasmin and plasminogen-derived activities varied with sampling month without a clear seasonal pattern. The pH of farm tank milk ranged from 6.60 to 6.82, with the lowest and highest values in September and February, respectively. The highest somatic cell count was observed in August (201 × 103 cells/mL) and the lowest in April (143 × 103 cells/mL). The highest value of gel strength, was recorded in December (88 Pa) and the lowest in July (64 Pa). Rennet coagulation time and gel strength were inversely correlated, with the lowest rennet coagulation time value observed in December. Orthogonal projections to latent structures (OPLS) and discriminant analysis adaptation of OPLS identified casein micelle size and total proteolysis as the milk quality attributes with major responses to sampling month, with smaller casein micelle size and higher total proteolysis associated with the outdoor months. Using discriminant analysis adaptation of OPLS to further investigate causes behind the variation in milk traits revealed that there were factors in addition to feeding on pasture that differed between outdoor and indoor months. Because fresh grass was seldom the primary feed in the region during the outdoor period, grazing was not considered the sole reason for the observed difference between outdoor and indoor periods in raw milk quality attributes.

Synthesis of Vertically Aligned ZnO Nanorods Using Sol-gel Seeding and Colloidal Lithography Patterning.

Different ZnO nanostructures can be grown using low-cost chemical bath deposition. Although this technique is cost-efficient and flexible, the final structures are usually randomly oriented and hardly controllable in terms of homogeneity and surface density. In this work, we use colloidal lithography to pattern (100) silicon substrates to fully control the nanorods' morphology and density. Moreover, a sol-gel prepared ZnO seed layer was employed to compensate for the lattice mismatch between the silicon substrate and ZnO nanorods. The results show a successful growth of vertically aligned ZnO nanorods with controllable diameter and density in the designated openings in the patterned resist mask deposited on the seed layer. Our method can be used to fabricate optimized devices where vertically ordered ZnO nanorods of high crystalline quality are crucial for the device performance.

Periodontitis, assessed using periodontal treatment as a surrogate marker, has no association with a first myocardial infarction in a Swedish population.

BACKGROUND: Periodontitis is suggested to be associated with a risk of cardiovascular events. Using periodontal treatment recorded in Swedish national registries as a surrogate marker, we aimed to investigate whether periodontitis was associated with a first myocardial infarction. METHODS: This nationwide case-control study, with data from national registries, involved 51,880 individuals with a first myocardial infarction in 2011 to 2013 (index date) and 246,978 controls matched 5:1 for age, gender, and geographic area. Periodontal treatment in the 3 years preceding the index date was classified as (1) no dental treatment, (2) no periodontal treatment, (3) one or more supragingival curettages, or (4) one or more treatments with scaling/root planing and/or periodontal surgery. Annual frequencies of treatment with scaling/root planing and/or periodontal surgery were also calculated. In all analyses, conditional logistic regression analyses estimated ORs for myocardial infarction with 95% CIs, adjusted for matched variables, income, education, and diabetes. RESULTS: Although fewer cases than controls received treatment with scaling/root planing and/or periodontal surgery (19.2% versus 19.8%, P < 0.001), annual frequencies for cases were higher. We found no association of scaling/root planing and/or periodontal surgery with a first myocardial infarction (OR = 1.02; 95% CI: 1.00, 1.05). We did observe a non-significant trend, however, between risk of a first myocardial infarction and a high frequency of scaling/root planing and/or periodontal surgery (OR 1.14; 95% CI: 1.00, 1.29). CONCLUSION: In the contemporary Swedish nationwide setting, no association between a first myocardial infarction and periodontitis, assessed as periodontal treatment, was found.

Adjunctive Antiseptic Irrigation of Periodontal Pockets: Effects on Microbial and Cytokine Profiles.

To evaluate the effect of adjunctive antiseptic irrigation of periodontal pockets on microbial and cytokine profiles. Fifty-nine patients with severe periodontitis were allocated to one of three groups for scaling and root planing facilitated with different adjunctive antiseptics: 1% polyhexamethyleneguanidine phosphate (PHMG-P) (n = 19), 0.2% chlorhexidine (CHX) (n = 21) or distilled water (n = 19). Gingival crevicular fluid and subgingival bacterial samples were collected at baseline, and at 2 weeks, and 1 and 4 months. The levels of interleukin (IL)-1ß, IL-8, IL-10, and IL-17A, matrix metalloproteinase (MMP)-8, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum,Aggregatibacter actinomycetemcomitans, and Prevotella intermedia were determined. There were no intergroup differences in cytokine concentrations and bacterial counts at any follow-up, however, varying patterns were observed. In the PHMG-P and water groups IL-1ß expression peaked at 2 weeks and then gradually declined. In all three groups, the dynamics of MMP-8 concentration were non-linear, increasing by 2 weeks and then declining to below baseline (p > 0.05). P. gingivalis and T. forsythia declined within the first month and increased thereafter, not regaining the baseline level. Adjunctive antiseptic treatment was associated with changes in biomarkers and bacterial counts in the course of the study. The effects of adjunctive antiseptic irrigation were limited in the applied protocol.

Investigating the emerging COVID-19 research trends in the field of business and management: A bibliometric analysis approach.

The COVID-19 pandemic has been labeled as a black swan event that caused a ripple effect on every aspect of human life. Despite the short time span of the pandemic-only four and half months so far-a rather large volume of research pertaining to COVID-19 has been published (107 articles indexed in Scopus and the Web of Science). This article presents the findings of a bibliometric study of COVID-19 literature in the business and management domain to identify current areas of research and propose a way forward. The analysis of the published literature identified four main research themes and 18 sub-themes. The findings and propositions of this study suggest that COVID-19 will be the catalyst of several long- and short-term policy changes and requires the theoretical and empirical attention of researchers. The offered propositions will act as a roadmap to potential research opportunities.