Testing of skeletonized human remains using GC/MS – development of a personal environmental profile

ABSTRACT

Gas chromatography/mass spectrometry (GC/MS) is well used in forensic science for the identification of materials present in toxicology, pharmacology and arson investigation. However, GC/MS has been underused in human identification. In this study, highly commingled skeletonized remains from a mass fatality incident involving over 400 individuals were examined. Environmental compounds and those present in the remains themselves were extracted from osseous materials removed from the surface of the skeletal elements using two different solvents, dichloromethane and acetonitrile. Solvent extracts were concentrated and resuspended in methanol prior to injection on the GC/MS instrument. Compounds present from the environment surrounding the individual post-mortem, as well as biological materials present in the individual ante-mortem, are detectable. Traces generated from the GC/MS instrument provide distinctive images, and analysis of those materials shows patterns that are specific to the individual and may be used for individuation. Results indicate that GC/MS analysis of skeletonized remains may be a new tool for human identification.     

Consumption of green tea favorably affects oxidative stress markers in weight-trained men

OBJECTIVE: This study investigated the effects of the consumption of green tea (GT) for 7 d on biomarkers of oxidative stress in young men undergoing resistance exercise. METHODS: Fourteen subjects performed a bench press exercise (four sets, 10 to 4 repetitions) after undergoing a period without (control group) or with the intake of GT (GT group; 2 g of leaves in 200 mL of water, three times per day). Blood samples were obtained before and after exercise and analyzed for total antioxidant capacity (ferric reducing ability of plasma [FRAP]), total polyphenols, reduced glutathione (GSH), lipid hydroperoxide (LH) and thiobarbituric acid-reactive substances, creatine kinase (CK), aspartate aminotransferase (AST), xanthine oxidase (XO), hypoxanthine, and uric acid (UA). RESULTS: In the control group, exercise did not affect the values of LH, thiobarbituric acid-reactive substances, and FRAP, although it did reduce the levels of GSH (P < 0.05). In addition, exercise increased CK, AST, and XO activities, although it did not change the values for hypoxanthine or UA. Green tea reduced the postexercise concentration of LH and increased the values of total polyphenols, GSH, and FRAP. GT also inhibited a significant rise in CK and XO activities induced by exercise. Furthermore, GT decreased the AST activity and hypoxanthine and UA concentrations before and after exercise. The assessment of food consumption revealed that the participants had an unbalanced diet, particularly in relation to vitamin E and carotenoids. CONCLUSION: Consumption of GT, a beverage rich in polyphenols, may offer protection against the oxidative damage caused by exercise, and dietary guidance for sports participants should be emphasized.     

Influence of different endodontic filling materials on root fracture susceptibility

OBJECTIVE: To evaluate the influence of different endodontic materials on root fracture susceptibility. METHODS: Seventy-two mandibular incisors were sectioned 1mm below the cementoenamel junction to obtain roots of 12 mm length. Roots were submitted to chemomechanical preparation with the rotary instruments of Profile system. The obturation of root canals were performed with the following filling materials (n=12): GI, unfilled teeth (control); GII, Endofill+gutta-percha; GIII, Sealer 26+gutta-percha; GIV, AH Plus+gutta-percha; GV, Epiphany+gutta-percha; GVI, Epiphany+Resilon. After the sealers setting time, each root was embedded in acrylic resin. The specimens were then submitted to fracture resistance test using an Instron testing machine at 1mm/min. RESULTS: The ANOVA test showed no significant statistical difference (p>.05) among GI (162.16+/-41.4N), GII (168.46+/-37.5N), GIII (164.83+/-35.7N), GIV (168.29+/-38.7N), GV (172.36+/-20.6N) and GVI (193.11+/-42.8N). CONCLUSION: The core materials (gutta-percha or Resilon) combined with the tested endodontic sealers are not able to increase the root fracture resistance in canals submitted to chemomechanical preparation.     

Detection of Helicobacter pylori resistance to clarithromycin and fluoroquinolones in Brazil: A national survey

AIMTo evaluate bacterial resistance to clarithromycin and fluoroquinolones in Brazil using molecular methods.METHODSThe primary antibiotic resistance rates of Helicobacter pylori (H. pylori) were determined from November 2012 to March 2015 in the Southern, South-Eastern, Northern, North-Eastern, and Central-Western regions of Brazil. Four hundred ninety H. pylori patients [66% female, mean age 43 years (range: 18-79)] who had never been previously treated for this infection were enrolled. All patients underwent gastroscopy with antrum and corpus biopsies and molecular testing using GenoType HelicoDR (Hain Life Science, Germany). This test was performed to detect the presence of H. pylori and to identify point mutations in the genes responsible for clarithromycin and fluoroquinolone resistance. The molecular procedure was divided into three steps: DNA extraction from the biopsies, multiplex amplification, and reverse hybridization.RESULTSClarithromycin resistance was found in 83 (16.9%) patients, and fluoroquinolone resistance was found in 66 (13.5%) patients. There was no statistical difference in resistance to either clarithromycin or fluoroquinolones (P = 0.55 and P = 0.06, respectively) among the different regions of Brazil. Dual resistance to clarithromycin and fluoroquinolones was found in 4.3% (21/490) of patients. The A2147G mutation was present in 90.4% (75/83), A2146G in 16.9% (14/83) and A2146C in 3.6% (3/83) of clarithromycin-resistant patients. In 10.8% (9/83) of clarithromycin-resistant samples, more than 01 mutation in the 23S rRNA gene was noticed. In fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test. D91N mutation was observed in 34.8% (23/66), D91G in 18.1% (12/66), N87K in 16.6% (11/66) and D91Y in 13.6% (9/66) of cases. Among fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test.CONCLUSIONThe H. pylori clarithromycin resistance rate in Brazil is at the borderline (15%-20%) for applying the standard triple therapy. The fluoroquinolone resistance rate (13.5%) is equally concerning.     

Patient selection criteria for blastocyst transfers in extended embryo culture programs

Purpose

To identify the correlation between different cycles, patient factors and blastocyst characteristics.

Methods

The study included 420 patients undergoing ICSI cycles and 2781 graded blastocysts, which took into account the blastocyst quality. The correlations between the blastocyst parameters and the patient and cycle characteristics were assessed.

Results

The blastocyst development was negatively correlated with the maternal age, BMI and dose of FSH. The ICM was negatively correlated with the FSH dose, whereas the TE quality was influenced by the FSH dose, the maternal age and the number of retrieved oocytes. The embryo morphology on days two and three may predict the blastocyst developmental competence.

Conclusions

Older patients and patients with high BMI should not be included in extended embryo culture programmes. The extended culture may not favour embryos with poor morphology on days two and three of development. Additionally, a lower ovarian stimulation and decreased oocyte yields may lead to the development of high-quality blastocysts.     

Passivity versus unilateral angular misfit: evaluation of stress distribution on implant-supported single crowns: three-dimensional finite element analysis

The aim of this study was to evaluate the effect of unilateral angular misfit of 100 μm on stress distribution of implant-supported single crowns with ceramic veneering and gold framework by three-dimensional finite element analysis. Two three-dimensional models representing a maxillary section of premolar region were constructed: group 1 (control)-crown completely adapted to the implant and group 2-crown with unilateral angular misfit of 100 μm. A vertical force of 100 N was applied on 2 centric points of the crown. The von Mises stress was used as an analysis criterion. The stress values and distribution in the main maps (204.4 MPa for group 1 and 205.0 MPa for group 2) and in the other structures (aesthetic veneering, framework, retention screw, implant, and bone tissue) were similar for both groups. The highest stress values were observed between the first and second threads of the retention screw. Considering the bone tissue, the highest stress values were exhibited in the peri-implant cortical bone. The unilateral angular misfit of 100 μm did not influence the stress distribution on the implant-supported prosthesis under static loading.