Observational and genetic associations between cardiorespiratory fitness and cancer: a UK Biobank and international consortia study.

BACKGROUND: The association of fitness with cancer risk is not clear. METHODS: We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of lung, colorectal, endometrial, breast, and prostate cancer in a subset of UK Biobank participants who completed a submaximal fitness test in 2009-12 (N = 72,572). We also investigated relationships using two-sample Mendelian randomisation (MR), odds ratios (ORs) were estimated using the inverse-variance weighted method. RESULTS: After a median of 11 years of follow-up, 4290 cancers of interest were diagnosed. A 3.5 ml O2⋅min-1⋅kg-1 total-body mass increase in fitness (equivalent to 1 metabolic equivalent of task (MET), approximately 0.5 standard deviation (SD)) was associated with lower risks of endometrial (HR = 0.81, 95% CI: 0.73-0.89), colorectal (0.94, 0.90-0.99), and breast cancer (0.96, 0.92-0.99). In MR analyses, a 0.5 SD increase in genetically predicted O2⋅min-1⋅kg-1 fat-free mass was associated with a lower risk of breast cancer (OR = 0.92, 95% CI: 0.86-0.98). After adjusting for adiposity, both the observational and genetic associations were attenuated. DISCUSSION: Higher fitness levels may reduce risks of endometrial, colorectal, and breast cancer, though relationships with adiposity are complex and may mediate these relationships. Increasing fitness, including via changes in body composition, may be an effective strategy for cancer prevention.

Manifestación clínica inicial de la lipomatosis epidural lumbar grado III de Naka: serie de casos / Initial clinical signs of Naka's grade III lumbar epidural lipomatosis: A case series

Introducción: La lipomatosis epidural espinal es una enfermedad infrecuente caracterizada por el sobrecrecimiento del tejido adiposo no encapsulado dentro del espacio epidural. Esto genera una estenosis del conducto espinal que puede provocar sintomatología compresiva. La presentación típica es insidiosa a lo largo de meses o años. El objetivo de este estudio fue realizar un análisis descriptivo de la manifestación clínica inicial en pacientes con lipomatosis epidural espinal grado III de Naka. Materiales y métodos: Estudio observacional retrospectivo en la Unidad de Patología Espinal de 4 instituciones, de 2010 a 2023. Se incluyó a pacientes >18 años, de ambos sexos, que acudieron por dolor lumbar con irradiación o sin irradiación, y presentaban lipomatosis lumbar Naka III en la resonancia magnética. Resultados: Se incorporó a 40 pacientes (edad promedio 62.5 años). El 75% era obeso, ninguno era fumador. El motivo de consulta más frecuente fue lumbalgia, con una mediana de evolución del dolor de 5.5 meses. Conclusiones:La lumbalgia fue la consulta más frecuente, con excepción del compromiso de L3-S1 que fue la lumbocruralgia. Los pacientes que sufrieron dolor más tiempo (>6 meses) eran más jóvenes y tenían un índice de masa corporal menor; sin embargo, no resultó estadísticamente significativo. Nivel de Evidencia: IV

Introduction: Spinal epidural lipomatosis (SEL) is a rare pathology characterized by the overgrowth of nonencapsulated adipose tissue within the epidural space. This generates spinal stenosis, which might result in compression symptoms. The typical presentation is insidious pain that lasts months or years. The objective of this study was to carry out a descriptive analysis of the initial clinical signs of patients with Naka's grade III lumbar SEL. materials and methods: Retrospective observational study in the Spinal Pathology Unit of 4 institutions, from 2010 to 2023. Patients over the age of 18, of both sexes, who consulted for low back pain with or without radiation and presented Naka's grade III lumbar lipomatosis on magnetic resonance imaging (MRI) were included. Results: We included 40 patients, with a mean age of 62.5 years; 75% were obese, there were no smokers. The most frequent reason for consultation was low back pain, with a median duration of 5.5 months. Conclusions: The most common reason for consultation was low back pain, with the exception of L3-S1 level involvement, which caused lumbar pain with radiation to the thigh. Patients with a longer period of pain (>6 months) were younger and had a lower BMI; although this was not statistically significant. Level of Evidence: IV

Real-world data on efficacy and safety of pembrolizumab in the first-line treatment of metastatic lung cancer in patients with PD-L1 expression >0% - a single center experience.

OBJECTIVE: With the advent of immunotherapy, there has been a significant improvement in the outcomes of non-small cell lung cancer treatment. Several clinical trials have confirmed the efficacy and safety of pembrolizumab, but research with real-world data is needed to confirm the findings from clinical trials. PATIENTS AND METHODS: In this retrospective study, data on the treatment of lung cancer with pembrolizumab were analyzed in 78 patients who started pembrolizumab therapy as first-line treatment for metastatic disease at University Hospital Centre Osijek, from May 15, 2018, until December 31, 2021. November 30, 2022, was set as the last date of data monitoring. Patients who had received less than 3 cycles of pembrolizumab were excluded from the study. The main objectives of the study were OS (overall survival) and PFS (progression-free survival). The differences in the incidence and type of adverse events between the two groups of patients were also compared. RESULTS: Kaplan-Meier analysis of the survival determined that the median OS was 20 months and PFS was 13 months. Although OS and PFS are longer in patients with PD-L1 (programmed death-ligand 1) ≥ 50%, the differences are not statistically significant. The most commonly reported adverse events related to pembrolizumab treatment were gastrointestinal adverse events. No significant differences were found in the frequency of occurrence of certain adverse events between the two groups of patients. CONCLUSIONS: This study demonstrates that real-world data for pembrolizumab treatment of non-small cell lung cancer confirm the efficacy and safety indicated by clinical trials. Nevertheless, it is necessary to assess the patient's general condition more objectively before starting the treatment.

Accuracy of periodontitis diagnosis obtained using multiple molecular biomarkers in oral fluids: A systematic review and meta-analysis.

AIM: To determine the accuracy of biomarker combinations in gingival crevicular fluid (GCF) and saliva through meta-analysis to diagnose periodontitis in systemically healthy subjects. METHODS: Studies on combining two or more biomarkers providing a binary classification table, sensitivity/specificity values or group sizes in subjects diagnosed with periodontitis were included. The search was performed in August 2022 through PUBMED, EMBASE, Cochrane, LILACS, SCOPUS and Web of Science. The methodological quality of the articles selected was evaluated using the QUADAS-2 checklist. Hierarchical summary receiver operating characteristic modelling was employed to perform the meta-analyses (CRD42020175021). RESULTS: Twenty-one combinations in GCF and 47 in saliva were evaluated. Meta-analyses were possible for six salivary combinations (median sensitivity/specificity values): IL-6 with MMP-8 (86.2%/80.5%); IL-1ß with IL-6 (83.0%/83.7%); IL-1ß with MMP-8 (82.7%/80.8%); MIP-1α with MMP-8 (71.0%/75.6%); IL-1ß, IL-6 and MMP-8 (81.8%/84.3%); and IL-1ß, IL-6, MIP-1α and MMP-8 (76.6%/79.7%). CONCLUSIONS: Two-biomarker combinations in oral fluids show high diagnostic accuracy for periodontitis, which is not substantially improved by incorporating more biomarkers. In saliva, the dual combinations of IL-1ß, IL-6 and MMP-8 have an excellent ability to detect periodontitis and a good capacity to detect non-periodontitis. Because of the limited number of biomarker combinations evaluated, further research is required to corroborate these observations.

Cardiorespiratory fitness assessment using risk-stratified exercise testing and dose-response relationships with disease outcomes.

Cardiorespiratory fitness (CRF) is associated with mortality and cardiovascular disease, but assessing CRF in the population is challenging. Here we develop and validate a novel framework to estimate CRF (as maximal oxygen consumption, VO2max) from heart rate response to low-risk personalised exercise tests. We apply the method to examine associations between CRF and health outcomes in the UK Biobank study, one of the world's largest and most inclusive studies of CRF, showing that risk of all-cause mortality is 8% lower (95%CI 5-11%, 2670 deaths among 79,981 participants) and cardiovascular mortality is 9% lower (95%CI 4-14%, 854 deaths) per 1-metabolic equivalent difference in CRF. Associations obtained with the novel validated CRF estimation method are stronger than those obtained using previous methodology, suggesting previous methods may have underestimated the importance of fitness for human health.

Shifting access to pools of shoot water sustains gas exchange and increases stem hydraulic safety during seasonal atmospheric drought.

Understanding how plants acclimate to drought is crucial for predicting future vulnerability, yet seasonal acclimation of traits that improve drought tolerance in trees remains poorly resolved. We hypothesized that dry season acclimation of leaf and stem traits influencing shoot water storage and hydraulic capacitance would mitigate the drought-associated risks of reduced gas exchange and hydraulic failure in the mangrove Sonneratia alba. By late dry season, availability of stored water had shifted within leaves and between leaves and stems. While whole shoot capacitance remained stable, the symplastic fraction of leaf water increased 86%, leaf capacitance increased 104% and stem capacitance declined 80%. Despite declining plant water potentials, leaf and whole plant hydraulic conductance remained unchanged, and midday assimilation rates increased. Further, the available leaf water between the minimum water potential observed and that corresponding to 50% loss of stem conductance increased 111%. Shifting availability of pools of water, within and between organs, maintained leaf water available to buffer periods of increased photosynthesis and losses in stem hydraulic conductivity, mitigating risks of carbon depletion and hydraulic failure during atmospheric drought. Seasonal changes in access to tissue and organ water may have an important role in drought acclimation and avoidance.

Complementary Saphenous Nerve Block to Intra-Articular Analgesia Reduces Pain After Total Knee Arthroplasty: A Prospective Randomized Controlled Trial.

BACKGROUND: Numerous strategies exist for pain management after total knee arthroplasty (TKA), with a fast recovery and early ambulation required for full function. Currently, there is no universal standard of care to facilitate this management. We assessed pain management safety and efficacy after TKA, using intra-articular infiltration associated with peripheral saphenous nerve block (SNB) vs intra-articular infiltration alone. METHODS: We performed a controlled, double-blinded, and randomized trial to evaluate postoperative pain in TKA. One group was treated with intra-articular analgesia associated with SNB, whereas a second group received the same intra-articular cocktail, associated with placebo. Efficacy was evaluated according to average pain, pain-free time, and morphine rescue indices. Safety was assessed by intervention complications and surgery. RESULTS: About 70 patients were recruited. At time 0 (immediately postoperative), 51.43% of the intra-articular analgesia + placebo group presented pain <3, whereas in the intra-articular analgesia + SNB group, 8.82% (P = .001) presented with pain. This difference was maintained at 6, 12, and 24 hours, postoperatively. After 24 hours, the placebo group received an average 0.66 morphine rescues (standard deviation, 0.86), when compared with the SNB group that received 0.14 rescues (standard deviation, 0.43), (P = .002). We recorded a paresis of the external popliteal sciatic nerve, with spontaneous recovery without other complications. CONCLUSION: Complementary SNB to intra-articular analgesia was more effective in reducing average pain and the amount of pain-free time in the first 24 hours after TKA, with fewer requests for morphine rescue analgesia.

Expression of gingival crevicular fluid markers during early and late healing of intrabony defects after surgical treatment: a systematic review.

BACKGROUND: Surgical treatments such as guided tissue regeneration (GTR) and access flap surgery are widely employed for the treatment of intrabony defects. However, little is known regarding the postoperative expression of gingival crevicular fluid (GCF) markers. OBJECTIVE: The aim of this systematic review was to compare the expression of GCF markers following treatment of periodontal intrabony defects with guided tissue regeneration or access surgery. The association of the markers' expression with the clinical outcome was also assessed. METHODS: An electronic literature search was conducted in MEDLINE, EMBASE, OpenGrey, LILACS and Cochrane Library up to December 2018 complemented by a manual search. Human, prospective clinical studies were identified. The changes from baseline up to 30 days (early healing) and 3 months (late healing) were assessed. RESULTS: A total of 164 publications were identified and reviewed for eligibility. Of these, 10 publications fulfilled the inclusion criteria. The included studies evaluated 15 different GCF markers with a follow-up time between 21 and 360 days postoperatively. PDGF, VEGF and TIMP-1 changes were often investigated in the included studies; however, contrasting results were reported. Two studies agreed that both GTR and OFD lead to similar OPG level changes. TGF-ß1 is increased early postoperatively, irrespective of the surgical technique employed. CONCLUSION: There is limited evidence available on the expression of GCF markers after surgical interventions of intrabony periodontal defects. However, OPG and TGF-ß1 tend to increase early post-operatively, irrespective of the surgical technique employed, irrespective of the surgical technique employed. CLINICAL RELEVANCE: More well-designed, powered studies with sampling periods reflecting the regenerative process are needed, and future research should focus on employing standardised protocols for collecting, storing and analysing GCF markers.

Unusual Listeria monocytogenes hematogenous infection in total knee replacement treated with one-stage revision surgery.

Septic arthritis due to Listeria monocytogenes (LM) is extremely rare and most infections due to this organism are seen in immunocompromised patients. We describe a patient without immunological compromise, with a late total knee arthroplasty infection caused by LM treated with one-stage revision surgery. She had an elevated erythrocyte sedimentation rate (79 mm/h) and C-reactive protein (13 mg/dL). Aspiration of the knee joint yielded purulent fluid; cultures showed LM. The patient was given 6 weeks of intravenous ampicillin, followed by trimethoprim/sulfamethoxazole, and finally amoxicillin orally for 7 months. Two years after revision surgery, radiographs showed no evidence of implant loosening. This is a single case and although one-stage approach seemed to have worked, it should not be recommended on the basis of a single report.

Secondary leaves of an outbreak-adapted tree species are both more resource acquisitive and more herbivore resistant than primary leaves.

The magnitude and frequency of insect outbreaks are predicted to increase in forests, but how trees cope with severe outbreak defoliation is not yet fully understood. Winter deciduous trees often produce a secondary leaf flush in response to defoliation (i.e., compensatory leaf regrowth or refoliation), which promotes fast replenishment of carbon (C) storage and eventually tree survival. However, secondary leaf flushes may imply a high susceptibility to insect herbivory, especially in the event of an ongoing outbreak. We hypothesized that in winter deciduous species adapted to outbreak-driven defoliations, secondary leaves are both more C acquisitive and more herbivore resistant than primary leaves. During an outbreak by Ormiscodes amphimone F. affecting Nothofagus pumilio (Poepp. & Endl.) Krasser forests, we (i) quantified the defoliation and subsequent refoliation by analyzing the seasonal dynamics of the normalized difference vegetation index (NDVI) and (ii) compared the physiological traits and herbivore resistance of primary and secondary leaves. Comparisons of the NDVI of the primary and second leaf flushes relative to the NDVI of the defoliated forest indicated 31% refoliation, which is close to the leaf regrowth reported by a previous study in juvenile N. pumilio trees subjected to experimental defoliation. Primary leaves had higher leaf mass per area, size, carbon:nitrogen ratio and soluble sugar concentration than secondary leaves, along with lower nitrogen and starch concentrations, and similar total polyphenol and phosphorus concentrations. In both a choice and a non-choice bioassay, the leaf consumption rates by O. amphimone larvae were significantly higher (>50%) for primary than for secondary leaves, indicating higher herbivore resistance in the latter. Our study shows that secondary leaf flushes in outbreak-adapted tree species can be both C acquisitive and herbivore resistant, and suggests that these two features mediate the positive effects of the compensatory leaf regrowth on the tree C balance and forest resilience.

Cytokine Thresholds in Gingival Crevicular Fluid with Potential Diagnosis of Chronic Periodontitis Differentiating by Smoking Status.

The objective of the present study was to determine cytokine thresholds derived from predictive models for the diagnosis of chronic periodontitis, differentiating by smoking status. Seventy-five periodontally healthy controls and 75 subjects affected by chronic periodontitis were recruited. Sixteen mediators were measured in gingival crevicular fluid (GCF) using multiplexed bead immunoassays. The models were obtained using binary logistic regression, distinguishing between non-smokers and smokers. The area under the curve (AUC) and numerous classification measures were obtained. Model curves were constructed graphically and the cytokine thresholds calculated for the values of maximum accuracy (ACC). There were three cytokine-based models and three cytokine ratio-based models, which presented with a bias-corrected AUC > 0.91 and > 0.83, respectively. These models were (cytokine thresholds in pg/ml for the median ACC using bootstrapping for smokers and non-smokers): IL1alpha (46099 and 65644); IL1beta (4732 and 5827); IL17A (11.03 and 17.13); IL1alpha/IL2 (4210 and 7118); IL1beta/IL2 (260 and 628); and IL17A/IL2 (0.810 and 1.919). IL1alpha, IL1beta and IL17A, and their ratios with IL2, are excellent diagnostic biomarkers in GCF for distinguishing periodontitis patients from periodontally healthy individuals. Cytokine thresholds in GCF with diagnostic potential are defined, showing that smokers have lower threshold values than non-smokers.

Cytokine-based Predictive Models to Estimate the Probability of Chronic Periodontitis: Development of Diagnostic Nomograms.

Although a distinct cytokine profile has been described in the gingival crevicular fluid (GCF) of patients with chronic periodontitis, there is no evidence of GCF cytokine-based predictive models being used to diagnose the disease. Our objectives were: to obtain GCF cytokine-based predictive models; and develop nomograms derived from them. A sample of 150 participants was recruited: 75 periodontally healthy controls and 75 subjects affected by chronic periodontitis. Sixteen mediators were measured in GCF using the Luminex 100™ instrument: GMCSF, IFNgamma, IL1alpha, IL1beta, IL2, IL3, IL4, IL5, IL6, IL10, IL12p40, IL12p70, IL13, IL17A, IL17F and TNFalpha. Cytokine-based models were obtained using multivariate binary logistic regression. Models were selected for their ability to predict chronic periodontitis, considering the different role of the cytokines involved in the inflammatory process. The outstanding predictive accuracy of the resulting smoking-adjusted models showed that IL1alpha, IL1beta and IL17A in GCF are very good biomarkers for distinguishing patients with chronic periodontitis from periodontally healthy individuals. The predictive ability of these pro-inflammatory cytokines was increased by incorporating IFN gamma and IL10. The nomograms revealed the amount of periodontitis-associated imbalances between these cytokines with pro-inflammatory and anti-inflammatory effects in terms of a particular probability of having chronic periodontitis.

Leukocyte receptor expression in chronic periodontitis.

BACKGROUND AND OBJECTIVE: Microbial recognition in the periodontium through specific leukocyte receptors gives rise to the response which in susceptible individuals can lead to periodontal diseases. The aim of this study was to explore the expression of leukocyte receptors in the gingival tissues of chronic periodontitis patients and to analyse differences between diseased and control sites (sites with probing pocket depth <4 mm). MATERIAL AND METHODS: Thirty-seven chronic periodontitis patients were included in the study. Gingival biopsies were harvested from diseased and control sites and processed by flow cytometry for the determination of the expression of 16 leukocyte receptors (CD4, CD8, CD11b, CD14, CD16, CD19, CD25, CD28, CD49d, CD49e, CD62, CD71, CD80, CCR7, Ly6G and HLA-DR). RESULTS: Expression of all studied receptors was higher in test compared with control sites (p < 0.005). Sampled sites with less bleeding on probing exhibited higher expression of CD16 and CD14 receptors (p = 0.020 and 0.011, respectively). CONCLUSIONS: This study points towards considerable differences in the expression of leukocyte receptors between diseased and control sites in the same periodontal patients.

[Effectiveness of a school-based program to prevent obesity]. / Efectividad de una intervención escolar contra la obesidad.

INTRODUCTION: Intervention for childhood obesity is a public health priority. The purpose of this study was to evaluate the effectiveness of an elementary school-based intervention against obesity in children. MATERIAL AND METHODS: Non-randomised controlled trial was conducted on children from first to fifth grade from two public schools of Avilés (Spain). The intervention lasted for 2 school years comprising healthy diet workshops, educational chats, educational meetings, informative written material, and promotion of physical activities. Primary outcome measure was body mass index z-score. Secondary outcomes included: obesity and overweight prevalence, waist circumference, dietary habits, and physical activity. RESULTS: A total of 382 (177 girls, 205 boys) out of 526 pupils of both schools were included in the study. Complete anthropometric data were obtained in 340 of the 382 individuals. Compared to children in control group, those in intervention group decreased body mass index z-score from 1.14 to 1.02 (P=.017), and improved KIDMED score from 7.33 to 7.71 points (P=.045). The percentage of students who carried on an optimal diet increased from 42.6% to 52.3% (P=.021). There were no statistical differences in the prevalence of obesity and overweight, or in waist circumference between the intervention and control groups. CONCLUSIONS: This school-based program resulted in modest beneficial changes in body mass index and diet quality.

Impact of delay in diagnosis on survival to head and neck carcinomas: a systematic review with meta-analysis.

OBJECTIVE: To address the contradictory information on the role of delay in diagnosis on head and neck cancer survival. STUDY DESIGN: Systematic review and meta-analysis. SEARCH STRATEGY: Search on MEDLINE (1966 to March 2011), EMBASE (1980 to March 2011) and ISI proceedings (from inception to March 2011). The terms used were ('Head and neck cancers') AND ('delay'OR'prognostic'OR'survival') both in MeSH terms and free-text words. The reference lists of the retrieved articles were also revised manually to identify other potentially relevant papers. All searches were independently undertaken by two clinicians and one epidemiologist, and the results merged. SETTING: Primary and specialised care levels. PARTICIPANTS: Meta-analysis of data from papers on the subject published from 1966 to 2011. MAIN OUTCOME MEASURES: Survival. METHODS: After search in Medline and other databases, we computed pooled relative risks (RR) and 95% confidence interval (95%CI) from the 10 studies retrieved. RESULTS: The estimate of the relative risk of mortality related to any diagnostic delay (either patient or professional delay) was 1.34 (95%CI 1.12-1.61). Referral delay was associated with a three-fold increase in mortality. Total delay was marginally related to mortality (RR: 1.04, 95%CI: 1.01-1.07). By anatomic location, pharynx cancer shows the highest association (RR: 1.68, 95%CI: 1.22-2.31). CONCLUSIONS: Diagnostic delay is a moderate risk factor of mortality from head and neck cancer. However, part of the effect observed may be due to residual confounding (confounding from unknown variables that are not eliminated by adjustment).

A novel mutation in the OFD1 (Cxorf5) gene may contribute to oral phenotype in patients with oral-facial-digital syndrome type 1.

BACKGROUND: Oral-facial-digital syndrome (OFDS) type 1 (OFD1) is an X-linked dominant condition associated with embryonic male lethality. It almost always affects the oral cavity, face, and digits. It is considered to be a ciliopathy caused by mutations in the OFD1 gene. A variety of mutations have been described, and a genotype-phenotype correlation has been suggested. OBJECTIVE AND METHODS: The proband was an 8-year-old Spanish girl with suspected OFD1. We extended the pedigree to three proband's generations, performing a thorough physical examination and screening for OFD1 mutations in nine individuals. RESULTS: The proband, her mother, and her sister showed oral findings consistent with OFD1. Ultrasound evaluation revealed the existence of renal cysts only in the proband's mother. The rest of the family (all male) had no relevant morphological abnormalities. A single-base deletion in exon 16 of OFD1 (c.2183delG) leading to a frameshift was detected in the proband, her mother, and her sister. CONCLUSION: Because all three women had a similar oral phenotype, this new mutation might be involved in the development of the OFD1 oral manifestations. In cases of OFDS, physical examination (including the oral cavity and renal function) and genetic screening of the probands and their relatives are mandatory.

Bacteraemia following dental implants' placement.

OBJECTIVE: To investigate the prevalence, duration and aetiology of bacteraemias following the placement of implants as well as the prophylactic efficacy of a chlorhexidine digluconate (CHX) mouthrinse. MATERIAL AND METHODS: Fifty patients undergoing implant placement were randomly distributed into two groups: CONTROL GROUP: 30 patients with no prophylactic intervention before surgery. CHX group: 20 patients who performed a 0.2% CHX mouthrinse before surgery. Blood samples were collected at baseline, at 30 s after the insertion of implants and at 15 min after completion of the suturing of the mucoperiosteal flap. Samples were processed in the Bactec 9240, and the subculture and further identification of the isolates were performed using conventional microbiological techniques. RESULTS: The prevalence of bacteraemias was 2% at baseline. In the control group, the prevalence of bacteraemias was 6.7% at 30 s and 3.3% at 15 min, but no statistically significant differences were achieved compared with the baseline percentage. In the CHX group, there were no positive cultures from blood samples obtained at 30 s or at 15 min. CONCLUSIONS: Implant placement via a mucoperiosteal flap does not carry a significant risk of developing bacteraemias. The use of antibiotic prophylaxis for the prevention of focal infections such as bacterial endocarditis in "at-risk" patients undergoing dental implants is therefore questionable. Although its efficacy has not been confirmed statistically, we recommend a 0.2% CHX mouthrinse before treatment as proposed previously by the British Society for Antimicrobial Chemotherapy.

Culture and characterization of mesenchymal stem cells from human gingival tissue.

BACKGROUND: Tissue engineering using mesenchymal stem cells (MSCs) is a recent therapeutic modality that has several advantages. MSCs have high proliferation potential and may be manipulated to permit differentiation before being transplanted, suggesting they may be an ideal candidate for regenerative procedures. Precise identification of cells capable of regenerating the periodontium is valuable because no predictable regeneration procedure has yet been described. The purpose of this study is to determine the presence of MSCs in human gingival connective tissue and their morphologic and functional characteristics. METHODS: Gingival connective tissue samples were obtained from five healthy students. The samples were deepithelialized, leaving only connective tissue. The explants were minced and cultured on tissue culture dishes for 3 to 4 weeks, after which cells were characterized by flow cytometry. Differentiation into osteogenic, chondrogenic, and adipogenic lineages was induced and evaluated by culture staining. An immunoregulation assay was also performed. RESULTS: The results show that gingival tissue cells fulfill the minimal criteria proposed by the International Society for Cellular Therapy to be defined as MSCs. Cell characterization was consistently positive for CD90, CD105, CD73, CD44, and CD13 markers and negative for hematopoietic markers CD34, CD38, CD45, and CD54. We observed differentiation in positive staining of adipogenic, chondrogenic, and osteogenic lineages. Furthermore, gingival cells showed immunomodulative capacity. CONCLUSION: Gingival connective tissue could be a reservoir of MSCs that could be used in regenerative procedures based on tissue engineering.

Substantivity of a single chlorhexidine mouthwash on salivary flora: influence of intrinsic and extrinsic factors.

OBJECTIVES: To analyse the influence of intrinsic and extrinsic factors on the in vivo antimicrobial activity of a chlorhexidine (CHX) digluconate mouthwash on the salivary flora up to 7h after its application, using epifluorescence microscopy. METHODS: Ten volunteers performed the following mouthwashes: 0.12% CHX (10ml/30s, 15ml/30s and 10ml/1min); 0.2% CHX (10ml/30s, 15ml/30s and 10ml/1min); 0.2% CHX (10ml/30s) plus different daily activities (eating, drinking, chewing or smoking). RESULTS: On comparing 0.12% CHX (10ml versus 15ml), the greatest differences in bacterial viability were detected at 1h and 3h. On comparing 0.12% CHX (30s versus 1min) the greatest differences in viability were detected at 1h, 3h, and 5h; and with 0.2% CHX (30s versus 1min), at 5h and 7h. On comparing 0.12% CHX (15ml) versus 0.2% CHX (10ml) and 0.12% CHX (1min) versus 0.2% CHX (30s), the percentage of viable bacteria was higher with the 0.12% concentration. On comparing 0.2% CHX versus 0.2% CHX plus daily activities, the higher differences were detected after eating and chewing, followed by drinking. CONCLUSION: An increase in the volume of 0.12% or 0.2% CHX mouthwashes does not affect the duration of antimicrobial activity in saliva, whereas increasing the duration produces a marked increase in substantivity. Substantivity was greater with 0.2% CHX than 0.12% CHX. Eating, chewing or drinking significantly reduces the 0.2% CHX substantivity in saliva.