Sex-Dependent Effects of 7,8-Dihydroxyflavone on Metabolic Health Are Associated with Alterations in the Host Gut Microbiome

7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies.     

Survival in cancer of the cervix: treatment in a population-based cancer registry in a developing country (Bangalore, India)

A survival analysis of treated cases of cervix cancer that were registered in the Bangalore (India) Population Based Cancer Registry between 1 January 1987 and 31 December 1989 was performed. Information on vital status of patients was obtained principally through follow-up visits to homes of patients. Follow-up information was available for 860 (92.7 percent) of 928 registered cases. Of the 860 cases, information on treatment was available for 559 patients, on whom the analysis of treatment outcome was performed. The overall five-year observed survival (5YS) was 41.1 percent with a relative survival of 46.3 percent. The 5YS was significantly (P = 0.01) influenced by clinical stage and by addition of brachytherapy (BT) to external radiotherapy (EXT) (5YS = 60.1 percent cf 27.4 percent, P = < 0.001). In 343 patients who received EXT only, comparatively better survival was seen in the group who had received between 4,800 to 5,999 centigray (cGy) (5YS = 36.1 percent) when compared with those who received less than 3,000 and 3,000 to 4,799 cGy (5YS = 16.7 percent and 24.9 percent, respectively). Doses of EXT higher than 5,999 cGy (in patients who were not suitable for BT) did not have any benefit in the 5YS (27.4 percent). The study has generated a specific hypothesis about possible needless excess dose of external radiotherapy.     

Prophylactic implantable cardioverter-defibrillator therapy in patients with left ventricular systolic dysfunction: a pooled analysis of 10 primary prevention trials

Strategies to decrease sudden cardiac death in patients with left ventricular systolic dysfunction are evolving. Recent clinical trials have evaluated the role of prophylactic implantable cardioverter-defibrillators (ICDs) in patients with and without additional risk stratifiers. We pooled studies comparing treatment with and without ICDs from published data and presented abstracts, irrespective of QRS duration and etiology of systolic dysfunction. On the basis of the available clinical trials, implantation of an ICD for primary prevention of death provides a 7.9% absolute mortality reduction (p = 0.003) in patients with left ventricular (LV) systolic dysfunction who were receiving optimized medical therapy. This finding was not sensitive to the exclusion of any individual trial. The ICD is an effective primary preventative measure in patients who are at risk for death; however, the application of this therapy needs to be individualized for the patient, similar to drug therapies in LV systolic dysfunction. In health care settings without unlimited resources, optimal use of this therapy will require better risk stratification methods or lowering of the initial device cost.     

Assessment of dental anxiety and its correlation with denture satisfaction in edentulous patients

Objective: The objectives of this study were to measure the level of dental anxiety and its correlation with dental history, denture satisfaction and other variables. Materials and methods: A cross-sectional study was conducted on 150 completely edentulous patients reporting to the Department of Prosthodontics, KLES's Institute of Dental Sciences, Belgaum, over a period of 17 months (August 2005 to March 2007). The anxiety level of the patients was assessed with the help of a questionnaire, after obtaining an informed consent. Reliability of the dental anxiety scale was assessed by means of coefficient alpha. Results: The results of this study concluded that dental anxiety scale for edentulous patients was a reliable scale for measuring dental anxiety. The anxiety score was higher for female than male patients. A significant correlation was found between denture satisfaction score and anxiety. Discussion: Anxiety plays a major role in denture satisfaction. The variables included: Previous denture experience, occupation, medical history, age, gender, dental anxiety scale, period of edentulousness, age of previous dentures, number of complete dentures, denture satisfaction score, and the score on the Hamilton anxiety scale Conclusion: The study indicated that gender correlates significantly with dental anxiety. Patients with medical history were found to be more anxious than normal patients. Patients with higher anxiety values were less satisfied with the treatment. Lastly, subjects with higher general anxiety showed greater values on the dental anxiety scale. Clinical significance: The assessment of dental anxiety will help the prosthodontist in the management of anxious patients and secondly to provide evidence-based research into this psychological construct which has been shown to predict dental avoidance. Keywords: Dental anxiety, Denture satisfaction, Completely edentulous patients. How to cite this article: Shrivastava R, Srivastava R, Shigli K, Prashanth MB, Kumaraswamy BN, Nethravathi TD. Assessment of Dental Anxiety and its Correlation with Denture Satisfaction in Edentulous Patients. J Contemp Dent Pract 2012;13(3):257-260. Source of support: Nil Conflict of interest: None declared.     

Basic research: Issues with animal experimentations

In vivo studies using the animals are helpful in developing the treatment strategies as they are important link between the successful in vitro testing and safe human use. Various research projects in the field of fixation of fractures, development of newer biomaterials, chemotherapeutic drugs, use of stem cells in nonunion of fractures and cartilage defects etc., have hugely depended on animal experimentation. The employment of animals in experiments is both scientific and ethical issue. There must be reasonable reasons to show that it will significantly advance the present knowledge and lead to improvement in care. The regulatory bodies exist for humane use and care of animals used for experiments e.g., International Council for Laboratory Animal Science, Council for International Organizations of Medical Sciences, International Union of Biological Sciences, International Committee on Laboratory Animals. In India, Indian National Science Academy, Indian Council of Medical Research, National Centre for Laboratory Animal Sciences promote high standards of laboratory animal quality, care and health. The Committee for the Purpose of Control and Supervision on Experiments on Animals guidelines are well defined and is a must read document for any one interested to carry out research with animal facilities.     

Evolving electroanatomic substrate and intra-atrial reentrant tachycardia late after Fontan surgery

Atrial Remodeling After the Fontan Operation. Introduction: The prevalence of intra‐atrial reentrant tachycardia (IART) increases with age in Fontan patients. This study aimed to characterize the atrial electroanatomic substrate for IART late after Fontan surgery. Methods and Results: Detailed electroanatomic mapping of the right atrium (RA) was performed in 11 consecutive patients (33 ± 9 years) with older style Fontan circulation (atriopulmonary and atrioventricular connection) who underwent their first radiofrequency catheter ablation (RFCA) for IART. A comparative group of 30 non‐Fontan congenital heart disease (CHD) patients were also studied. Fontan patients had larger RA (P = 0.004), larger low‐voltage area ≤0.5 mV (P = 0.01), and more fractionated potentials (P < 0.001) than non‐Fontan CHD patients. RA enlargement correlated significantly with both low‐voltage zones (Spearman ρ= 0.68, P < 0.001) and fractionated potentials (Spearman ρ= 0.48, P = 0.001). Among Fontan patients, both age and time since Fontan surgery were significantly correlated to the amount of low‐voltage areas (Spearman ρ= 0.87, P < 0.001; Spearman ρ= 0.63, P = 0.04, respectively). Successful RFCA was accomplished in 30 (73%) patients and was less likely in Fontan patients (54% vs 83%, P = 0.04). Larger RA was significantly associated with a lower success rate (P = 0.04). During a follow‐up duration of 2.3 ± 1.6 years, IART recurred in 47% of patients. Larger RA size and larger low‐voltage areas predicted IART recurrence after RFCA. Conclusion: Fontan patients demonstrate progressive adverse atrial electrical remodeling with increasing age and time since surgery. Newer strategies beyond surgical incisions, such as pharmacotherapies that retard the progression of atrial fibrosis, may be required to reduce the long‐term risk of atrial arrhythmias.     

Is Inappropriate Implantable Defibrillator Shock Therapy Predictable?

Objective: To identify implantable cardioverter defibrillator (ICD) patients who are at risk of receiving inappropriate shock. Background: Inappropriate ICD shock, usually from atrial fibrillation (AF) or sinus tachycardia (ST), is a common problem. We hypothesized that clinical variables would predict which patients with single chamber ICDs would be more likely to receive inappropriate therapy and be candidates for more accurate discriminators such as those available in dual chamber ICDs. Methods: The ICD registry at St. Michael's Hospital has it's clinical information and demographic data updated after each clinic visit. Inappropriate shock was considered as the outcome variable. Possible predictors considered were age, gender, ejection fraction, NYHA class, prior CABG and prior history of AF. Univariate predictors were identified using t-test for continuous variables and Chi-square test for categorical variables. Multivariate predictors were identified using stepwise logistic regression analyses. Results: Of 299 patients, 261 had complete data for analysis. In this population 78% were male, mean age was 60 ± 13 years, mean ejection fraction was 37 ± 15% and mean follow up was 53 ± 36 months. One hundred and sixteen of the 261 patients (44%) received one or more inappropriate therapies (73% within 2 years of receiving their device), and 140 (51%) received one or more appropriate therapies. Significant predictors of inappropriate therapy by multivariate model were prior AF (OR 2.6, 95% CI 1.5–4.5) and NYHA class 1 vs. classes 2–4 (OR 2.2, 95% CI 1.2–3.7). Conclusion: Clinical characteristics of ICD patients can predict those at risk for inappropriate shock and should be considered for interventions to decrease such shocks.