A Simple and Inexpensive Method to Gain Diatom Absolute Abundances from Permanent Mounts in Hydrobiological and Paleoecological Research

Here, we describe and discuss a method based on microscopical field of view (FOV) area to estimate diatom absolute abundances (densities or concentrations), and we statistically verify its reliability, also comparing it to another commonly used method (microspheres). To test the new method, we purposely performed replicate counts, both with the FOV and with the microsphere method, on both subfossil and recent material (samples) from mires. Intraclass correlation (ICC) revealed a high degree of agreement between the measurements obtained for the replicates with each of the two methods, suggesting that both are reliable for measuring diatom valve concentrations. However, the FOV consistently overestimated diatom absolute abundances, as compared to the microsphere method, and the ICC value used to assess the reliability of the two methods combined suggested that the two methods cannot be used interchangeably. The FOV method is relatively simple, has a lower cost, wider applicability, higher resolution, and warrants compatibility with existing datasets. However, there may also be drawbacks, such as the potential for sample distortion during the concentration process. Therefore, it is important to carefully evaluate the strengths and limitations of the different methods before adopting one for specific research or applied questions

Subgingival Instrumentation for Treatment of Periodontitis. A Systematic Review

OBJECTIVES: To evaluate the efficacy of subgingival instrumentation (PICOS-1), sonic/ultrasonic/hand instruments (PICOS-2) and different subgingival instrumentation delivery protocols (PICOS-3) to treat periodontitis. METHODS: Systematic electronic search (CENTRAL/MEDLINE/EMBASE/SCOPUS/LILACS) to March 2019 was conducted to identify randomized controlled trials (RCT) reporting on subgingival instrumentation. Duplicate screening and data extraction were performed to formulate evidence tables and meta-analysis as appropriate. RESULTS: As only one RCT addressed the efficacy of subgingival instrumentation compared to supragingival cleaning alone (PICOS-1), baseline and final measures from 11 studies were considered. The weighted pocket depth (PD) reduction was 1.7 mm (95%CI: 1.3-2.1) at 6/8 months and the proportion of pocket closure was estimated at 74% (95%CI: 64-85). Six RCTs compared hand and sonic/ultrasonic instruments for subgingival instrumentation (PICOS-2). No significant differences were observed between groups by follow-up time point or category of initial PD. Thirteen RCTs evaluated quadrant-wise vs full-mouth approaches (PICOS-3). No significant differences were observed between groups irrespective of time-points or initial PD. Five studies reported patient-reported outcomes, reporting no differences between groups. CONCLUSIONS: Nonsurgical periodontal therapy by mechanical subgingival instrumentation is an efficacious means to achieve infection control in periodontitis patients irrespective of the type of instrument or mode of delivery. Prospero ID:CRD42019124887

Complications and treatment errors in periodontal therapy in medically compromised patients

Patients who are medically compromised may be at an increased risk of complications and treatment errors following periodontal therapy. A review of the evidence on the topic is presented, in relation to the type of complication reported, of periodontal treatment, and of patients' medical status. Further, a framework for risk assessment and appropriate treatment modifications is introduced, with the aim of facilitating the management of patients with existing comorbidities and reducing the incidence of treatment complications

Periodontitis and Systemic Lupus Erythematosus: A systematic review and meta-analysis

This systematic review and meta-analysis evaluated the association between periodontitis (PD) and systemic lupus erythematosus (SLE). A systematic search was conducted through the following electronic databases: Cochrane Library, MEDLINE, EMBASE, Scopus, LILACS, CINAHL and SIGLE (System for Information on Grey Literature in Europe) for relevant publications up to September 2020 with no language restriction. The association between PD and SLE was assessed by the prevalence of PD in SLE patients (both sex and females only) as the primary outcome. Secondary outcomes included differences in common gingival parameters including probing pocket depth (PPD), clinical attachment level (CAL), disease activity index (SLEDAI) scores of SLE patients with or without PD. A total of 1183 citations and 22 full text articles were screened. Eighteen articles were included in the qualitative synthesis, and 13 in the quantitative analysis. SLE diagnosis was associated with greater odds of PD (OR = 1.33, 95% Confidence Interval [CI]: 1.20–1.48), but these were non-significant when examined in females (OR = 3.20, 95%CI: 0.85–12.02). Patients with SLE exhibited no differences in PPD (SMD: −0.09 mm, 95%CI: −0.45–0.27) and CAL (SMD: 0.05 mm, 95%CI: −0.30–0.40) when compared with systemically healthy controls. PD diagnosis was, however, associated with higher SLEDAI scores in patients suffering from SLE (SMD: 0.68, 95% CI: 0.03–1.32). PD and SLE are both inflammatory diseases and their association could be bi-directional. This review suggested that the patients with SLE have greater odds of suffering with PD. Further investigations are required to assess the association between PD and SLE

Periodontitis and vascular inflammatory biomarkers: an experimental in vivo study in rats

The objective of this preclinical in vivo study was to determine changes in vascular inflammatory biomarkers in systemic circulation after injection of lipopolysaccharide (LPS) from Porphyromonas gingivalis (Pg) in rats. Experimental periodontitis was induced by injections of Pg-LPS. Gingival soft and hard tissues changes were analysed by means of magnetic resonance imaging and micro computed tomography. Serum levels of interleukin (IL)-6, IL-10, pentraxin (PTX) 3, and soluble fragment of tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) were determined at baseline and 24 h, 7, 14, and 21 days after periodontal induction. Significant periodontal inflammation and alveolar bone loss were evident at the end of periodontal induction. Experimental periodontitis posed an acute systemic inflammatory response with increased serum levels of IL-6 and PTX3 at 24 h post-induction, followed by a significant overexpression of sTWEAK at 7 days. This inflammatory state was maintained until the end of the experiment (21 days). As expected, IL-10 serum levels were significantly lower during the follow-up compared to baseline concentrations. In the present animal model, experimental periodontitis is associated with increased systemic inflammation. Further studies are needed to confirm whether PTX3 and sTWEAK could be useful biomarkers to investigate potential mechanisms underlying the relationship between periodontitis and atherosclerotic vascular diseases

Periodontitis and Systemic Markers of Neurodegeneration. A case-control study

Aim: To investigate whether periodontitis is associated with amyloid beta (Aβ) peptides and whether systemic inflammation could act as a potential mediator of this link. Materials and Methods: A case–control study was designed including 75 patients with periodontitis (cases) and 75 age‐balanced and gender‐matched participants without periodontitis (controls). Full‐mouth periodontal evaluation was performed in all participants. Demographic, clinical and behaviour data were also recorded. Fasting blood samples were collected, and serum levels of interleukin 6 (IL‐6), high‐sensitivity C‐reactive protein (hs‐CRP), Aβ1‐40 and Aβ1‐42 were determined. Results: Cases showed higher levels of IL‐6 (8.7 ± 3.2 vs. 4.8 ± 0.5 pg/ml), hs‐CRP (3.3 ± 1.2 vs. 0.9 ± 0.7 mg/L), Aβ1‐40 (37.3 ± 6.0 vs. 30.3 ± 1.8 pg/ml) and Aβ1‐42 (54.5 ± 10.6 vs. 36.5 ± 10.0 pg/ml) when compared to controls (all p < .001). Diagnosis of periodontitis was statistically significantly associated with circulating Aβ1‐40 (urn:x-wiley:03036979:media:jcpe13267:jcpe13267-math-0001 = 6.9, 95% CI: 5.4–8.3; p < .001) and Aβ1‐42 (urn:x-wiley:03036979:media:jcpe13267:jcpe13267-math-0002 = 17.8, 95% CI: 14.4–21.3; p < .001). Mediation analysis confirmed hs‐CRP and IL‐6 as mediators of this association. Conclusions: Periodontitis is associated with increased peripheral levels of Aβ. This finding could be explained by enhanced systemic inflammation that can be seen in patients with periodontitis

Remote ischemic preconditioning (RIPC) protects against endothelial dysfunction in a human model of systemic inflammation: a randomized clinical trial

Objective: Inflammation, oxidative stress, and endothelial dysfunction are known to contribute to ischemia-reperfusion injury. Remote ischemic preconditioning (RIPC) protects from endothelial dysfunction and the damage induced by ischemia-reperfusion. Using intensive periodontal treatment (IPT), an established human model of acute systemic inflammation, we investigated whether RIPC prevents endothelial dysfunction and modulates systemic levels of inflammation and oxidative stress. Approach and Results: Forty-nine participants with periodontitis were randomly allocated to receive either 3 cycles of ischemia-reperfusion on the upper limb (N=24, RIPC) or a sham procedure (N=25, control) before IPT. Endothelial function assessed by flow-mediated dilatation of the brachial artery, inflammatory cytokines, markers of vascular injury, and oxidative stress were evaluated at baseline, day 1, and day 7 after IPT. Twenty-four hours post-IPT, the RIPC group had lower levels of IL-10 (interleukin-10) and IL-12 (interleukin-12) compared with the control group (P<0.05). RIPC attenuated the IPT-induced increase in IL-1β (interleukin-1β), E-selectin, sICAM-3 (soluble intercellular adhesion molecule 3), and sTM (soluble thrombomodulin) levels between the baseline and day 1 (P for interaction <0.1). Conversely, oxidative stress was differentially increased at day1 in the RIPC group compared with the control group (P for interaction <0.1). This was accompanied by a better flow-mediated dilatation (mean difference 1.75% [95% CI, 0.428–3.07], P=0.011). After 7 days from IPT, most of the inflammatory markers, endothelial-dependent and -independent vasodilation, were similar between groups. Conclusions: RIPC prevented acute endothelial dysfunction by modulation of inflammation and oxidation processes in patients with periodontitis following exposure to an acute inflammatory stimulus

Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund