Nitrate reduction capacity of the oral microbiota is impaired in periodontitis: potential implications for systemic nitric oxide availability.

The reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity (NRC) and, therefore, nitric oxide availability has not been evaluated. The current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitrate-reducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals (P < 0.05 in all five datasets with n = 20-82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. The oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate (a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15 healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment (P < 0.05) but recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria (P < 0.01). No significant effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.

Interactions of beet leafhopper (Hemiptera: Cicadellidae), vector of beet curly top virus, and hemp in New Mexico.

The beet leafhopper, Circulifer tenellus (Baker 1896), is the sole vector of beet curly top virus (BCTV). Both the virus and the vector have very wide host ranges, including many crops and weeds. Industrial hemp (Cannabis sativa L.) has been reported as a host for both the virus and leafhopper in the past few years with the legal cultivation of the crop in the United States. This research assessed the interactions of the beet leafhopper and hemp in New Mexico by determining the natural infection of hemp with BCTV in 3 field plots in 2021 and 2022 and monitoring the numbers of leafhoppers using yellow sticky traps. The relative preference of beet leafhopper for hemp types and varieties of hemp was assessed using cafeteria-style choice tests. Higher numbers of beet leafhoppers were trapped in and around hemp fields in 2022 than in 2021 in all 3 locations. BCTV was found to infect all 3 types of hemp (cannabidiol or CBD, fiber, and grain) in 2022 in 1 location and only a single CBD variety of hemp in the other 2 locations. Two BCTV strains were identified in CBD hemp, while an additional BCTV strain was found infecting chile pepper grown at the same location.

The systemic inflammatory response following hand instrumentation versus ultrasonic instrumentation-A randomized controlled trial.

OBJECTIVE: This study sought to investigate whether the immediate systemic inflammatory response following full-mouth debridement differs following use of hand compared with ultrasonic instruments. METHODS: Thirty-nine periodontitis patients were randomized to treatment with full-mouth debridement using either hand or ultrasonic instrumentation completed within 24 hr. Serum and periodontal clinical parameters were collected at baseline, day 1, day 7 and day 90 post-treatment. Differences in systemic inflammatory markers were assessed using general linear models at each timepoint, corrected for age, gender, smoking status, body mass index and baseline levels of each marker. RESULTS: Across all patients, serum C-reactive protein increased at day 1, with no differences between hand and ultrasonic groups (p(adjusted) = .22). There was no difference between groups in interleukin-6 (p(adjusted) = .29) or tumour necrosis factor α (p(adjusted) = .53) at day 1. Inflammatory markers returned to baseline levels by day 7. Treatment resulted in equal and marked improvements in clinical parameters in both groups; however, total treatment time was on average shorter for ultrasonic instruments (p(adjusted) = .002). CONCLUSIONS: Ultrasonic instrumentation resulted in shorter treatment time with comparable clinical outcomes. Levels of serum C-reactive protein at day 1 were similar following debridement with hand or ultrasonic instruments.