A colourimetric evaluation of the effect of bacterial contamination on teeth stained with blood in vitro: Evaluation of the efficacy of two different bleaching regimes.

BACKGROUND: Tooth discolouration could occur due to bacterial contamination in traumatized teeth. Hydrogen peroxide is the commonly used bleaching agent. However, due to concerns over safety, alternative bleaching regimes such as sodium perborate (S) and thiourea-hydrogen peroxide (T) have been investigated. METHODS: Apices resected and pulp extirpated 99 premolars were divided into two groups. Group 1 and 2 was injected with blood and blood/bacteria, stored anaerobically for 35 days. The two groups were treated by bleaching with water, S or T. Teeth were rebleached after 7 days. Colourimetric evaluation was assessed using digital imaging, CasMatch standardization and CIE L*a*b colour system preoperatively, 35 days of staining and 7 and 14 of bleaching. A linear mixed model with fixed effects of time, group and bleach was used to examine colour difference. RESULTS: Blood-stained teeth were significantly redder and darker on day 35 compared with blood/bacteria-stained teeth. After bleaching, blood-stained teeth retained significant redness compared with blood/bacteria-stained teeth using either S or T. T produced a significantly whiter shade in both the groups after 14 days. CONCLUSIONS: Blood-stained teeth were significantly darker and red compared with blood/bacteria-stained teeth. T bleaching regime was more effective than S.

Clonal diversity in biofilm formation by Enterococcus faecalis in response to environmental stress associated with endodontic irrigants and medicaments.

AIM: To determine whether clonal diversity within E. faecalis affects biofilm formation when exposed to antimicrobial compounds found in endodontic medicaments and irrigants. METHODOLOGY: Five human isolates of E. faecalis were compared; biofilms were grown in microtitre trays in the presence of sodium hypochlorite, calcium hydroxide, chlorhexidine, tetracycline or clindamycin. Biofilms were quantified by staining with crystal violet and optical density determined with a microplate reader. Slime production (an amorphous extracellular matrix comprising polysaccharides, glycoproteins and glycolipids loosely attached to the cell surface) was determined qualitatively by growth on Congo red agar plates. Linear mixed models were used to examine whether medicaments affected biofilm growth of the isolates in the presence of the medicaments or irrigants. RESULTS: Overall, different endodontic antimicrobials significantly altered biofilm growth in E. faecalis isolates. Two E. faecalis isolates significantly (P < 0.0001) increased biofilm formation in the presence of tetracycline and one in the presence of NaOCl (P = 0.018). Qualitatively, slime production also varied between isolates and correlated with biofilm production. CONCLUSIONS: When subjected to sub-minimum inhibitory concentration (MIC) levels of antimicrobial compounds found in endodontic medicaments, E. faecalis isolates demonstrated significant clonal variation in their capacity to form biofilms. Interestingly, there was a correlation between slime production and the ability of isolates to form a biofilm in the presence of antimicrobials. The results indicate that isolates of E. faecalis that form biofilms in response to endodontic medicaments may be more likely to survive endodontic treatment.

Adherence and outcomes of patients prescribed dabigatran (Pradaxa) in routine clinical practice.

AIM: To explore and detail clinical experiences of dabigatran, a novel anticoagulant, after it became available in New Zealand in July 2011. METHODS: A cohort of patients was recruited from Hutt Hospital and the two largest primary care practices in the Hutt Valley region. They were included if they took at least one dose of dabigatran between July 2011 and April 2012. Participants undertook a questionnaire 3-12 months after starting dabigatran assessing adherence, perceived side-effects and complications. Those presenting due to an adverse event were analysed separately. RESULTS: Of 102 patients identified, 92 were recruited to this study. At a median of 8 months, 70% of participants were still taking dabigatran, significantly lower than in the RE-LY trial at 12 months (P = 0.0002). The commonest reason given for discontinuation was gastrointestinal (GI) side-effects. Rates of serious adverse outcomes on dabigatran therapy were relatively low. Patients expressed polarised comments, both positive and negative, regarding their experiences of dabigatran. CONCLUSIONS: A high rate of discontinuation of dabigatran, mainly due to GI symptoms, was observed. There does not appear to be any specific predictor of dabigatran tolerance. When prescribed according to guidelines, rates of serious adverse events associated with dabigatran appear to be low.

Adjustment to infertility: the role of intrapersonal and interpersonal resources/vulnerabilities.

BACKGROUND: Great variability exists in the degree of adjustment to infertility, which in turn is known to influence wellbeing. The main objective of this study is to identify intrapersonal [neuroticism, adult attachment style (AAS), perceived internal control, meaning of parenthood and intrinsic religiosity] and interpersonal (social support and marital adjustment) associates of adjustment to infertility. METHOD: A cross-sectional analysis of 85 consecutive heterosexual women, attending three infertility clinics in northern India during July 2005-March 2006, participated in the study. A range of scales were used to measure the intrapersonal and interpersonal attributes. The degree of adjustment to infertility was assessed using the Fertility Adjustment Scale. The data were analysed using multiple regression. RESULTS: The intrapersonal model (49.3%) explained a larger proportion of variance than did the interpersonal model (28.4%). Perception of children as necessary for marital completion, and the avoidance type of AAS was associated with poorer adjustment and constituted intrapersonal vulnerabilities. In contrast, intrinsic religiosity, sexual satisfaction and familial support were associated with better adjustment and were identified as helpful intrapersonal and interpersonal coping resources. CONCLUSIONS: The findings of the study highlight the merit of understanding intra- and interpersonal attributes for achieving better wellbeing outcomes. These findings would also prove valuable for researchers and practioners involved in designing and implementing psychosocial interventions.

Factors and perceptions that influence women's decisions to have a single embryo transferred.

The aim of this study was to identify factors that inhibit or promote the adoption of single embryo transfer (SET). A cohort of 163 women patients receiving IVF/intracytoplasmic sperm injection treatment, comprising 87 women choosing SET and 63 women choosing double embryo transfer (DET), were interviewed using a structured questionnaire. The data were compared using logistic regression analysis. Confidence in the chance of pregnancy with SET, younger age and first treatment were predictive of a decision for SET. Preference for a healthy and singleton pregnancy was predictive but perceptions of the incidence or risk of multiple gestation were not. Factors such as a sense of time urgency and past experience of treatment were significant and predictive of diminished choice of SET. The clinic doctor was an important influencing factor. The results of this study confirm that improved pregnancy rates in SET coupled with an official clinic policy to promote SET in younger, first cycle patients influenced many women to choose SET. However, repeated treatment, advancing age and urgency to become pregnant are factors that moderate a woman's choice for SET.

Seat belt use among Hispanic ethnic subgroups of national origin.

OBJECTIVE: Findings from over a dozen studies of Hispanic/white disparities in seat belt use have been inconsistent, variably revealing that seat belt use prevalence among Hispanics is higher, lower, or comparable to use among non-Hispanics. In contrast to previous studies, this study investigates disparities in seat belt use by Hispanic subgroups of national origin. METHODS: Data from the US Fatality Analysis Reporting System were used to compare seat belt use among 60 758 non-Hispanic whites and 6879 Hispanics (Mexican American (MA), n = 5175; Central American/South American (CASA), n = 876; Puerto Rican (PR), n = 412; Cuban (CU), n = 416) killed in crashes from 1999-2003. Logistic regression was used to adjust for age, gender, seat belt law, seat position, urban/rural region, and income. RESULTS: Overall adjusted odds ratios for seat belt use among Hispanic subgroups, relative to non-Hispanic whites, were 1.04 (95% confidence interval (CI) 0.85 to 1.28) for CUs, 1.17 (95% CI 0.95 to 1.44) for PRs, 1.33 (95% CI 1.25 to 1.42) for MAs, and 1.66 (95% CI 1.44 to 1.91) for CASAs. Relative to their non-Hispanic white counterparts, odds ratios among MA and CASA Hispanics were highest for men, younger age groups, drivers, primary law states, rural areas, and lower income quartiles. CONCLUSION: Among all Hispanic subgroups, seat belt use was at least as prevalent as among non-Hispanic whites. In the CASA and MA subgroups, which have the most rapidly growing subpopulations of immigrants, seat belt use was significantly more common than among whites.

Using a nursing protocol to assure equitable delivery of cancer-related prevention services.

A nurse-administered, protocol-driven model (NP) for preventive services delivery was compared with a traditional physician reminder (PR) model with nursing back-up among 473 patients attending Internal Medicine and Family Medicine clinics. A total of 240 patients were randomized to the NP group and 233 to the PR group. Demographic characteristics including gender [71% female (NP) and 71% female (PR)], race (78% and 75% African American, respectively) and age (numbers of persons aged 18-54, 55-64 and 65+ years) were similar in each group. In the NP group 244/244 screening tests for breast, cervical and colon cancers and alcohol abuse were initiated or completed by nurses, while in the PR group 110/215 (51%) were initiated or completed by physicians. The NP group received 552/552 counseling services from nurses for tobacco, alcohol, nutrition, exercise and prostate screening, while in the PR group, physicians delivered 10% of the needed services (56/560). Aside from counseling for prostate cancer screening, which was 100% in both the NP and PR groups, all other between-group differences for each service were significant at the level of p<0.001. Results show the feasibility of a nursing protocol for initiating equitable cancer prevention services in a primary care setting.

A flowchart for managing sexually transmitted infections among Nigerian adolescent females.

OBJECTIVE: To devise a flowchart suitable for assessing risk of trichomoniasis, chlamydia and gonorrhoea in an adolescent population, not all of whom will be sexually experienced or currently in a relationship. METHODS: The data used to derive the flowchart were generated from cross-sectional microbiological surveys of girls aged 14-19 years in Port Harcourt, Nigeria. The flowchart screened on the basis of: (i) sexual experience; (ii) recent sexual activity; (iii) a positive urine leukocyte esterase (LE) test; and (iv) among LE negatives, a history of malodorous/pruritic discharge. FINDINGS: Using this flowchart, we found that 26.2% of all adolescents screened would receive treatment for cervicitis and vaginitis. Chlamydial, gonococcal, and trichomonal infections were correctly diagnosed in 37.5%, 66.7%, and 50% of the cases, respectively. CONCLUSION: Although the flowchart is more suitable for an adolescent population than the vaginal discharge algorithm used in syndromic management protocols, it still lacks precision and needs adapting to local settings.

Black-white inequalities in mortality and life expectancy, 1933-1999: implications for healthy people 2010.

OBJECTIVES: Optimistic predictions for the Healthy People 2010 goals of eliminating racial/ethnic disparities in health have been made based on absolute improvements in life expectancy and mortality. This study sought to determine whether there is evidence of relative improvement (a more valid measure of inequality) in life expectancy and mortality, and whether such improvement, if demonstrated, predicts future success in eliminating disparities. METHODS: Historical data from the National Center for Health Statistics and the Census Bureau were used to predict future trends in relative mortality and life expectancy, employing an Autoregressive Integrated Moving Average (ARIMA) model. Excess mortality and time lags in mortality and life expectancy for blacks relative to whites were also estimated. RESULTS: Based on data for 1945 to 1999, forecasts for relative black:white age-adjusted, all-cause mortality and white:black life expectancy at birth showed trends toward increasing disparities. From 1979, when the Healthy People initiative began, to 1998, the black:white ratio of age-adjusted, gender-specific mortality increased for all but one of nine causes of death that accounted for 83.4% of all US mortality in 1998. From 1980 to 1998, average numbers of excess deaths per day among American blacks relative to whites increased by 20%. American blacks experienced 4.3 to 4.5 million premature deaths relative to whites in 1940-1999. CONCLUSIONS: The rationale that underlies the optimistic Healthy People 2010 forecasts, that future success can be built on a foundation of past success, is not supported when relative measures of inequality are used. There has been no sustained decrease in black-white inequalities in age-adjusted mortality or life expectancy at birth at the national level since 1945. Without fundamental changes, most probably related to the ways medical and public health practitioners are trained, evaluated, and compensated for prevention-related activities, as well as further research on translating the findings of prevention studies into clinical practice, it is likely that simply reducing disparities in access to care and/or medical treatment will be insufficient. Millions of premature deaths will continue to occur among African Americans.

Tetanus antibody levels among adolescent girls in developing countries.

Neonatal and maternal tetanus infections remain an important cause of death in many countries. Few studies have reported tetanus toxoid antibody levels of adolescent girls. As part of the Expanded Programme on Immunization most girls receive up to 3 injections in early childhood, and many subsequently do not receive booster vaccinations until pregnant. We determined (by ELISA) tetanus antibody seropositivity in adolescent girls from Malawi (in 1996), Nigeria (in 1993) and Pakistan (in 1996), and response to tetanus vaccination in adolescent girls from Pakistan. Geometric mean titres (GMT, IU/mL) were 0.94 in 117 Malawian, 0.32 in 154 Nigerian and 1.08 in 162 Pakistani girls. In Nigeria, 54.7% of adolescents were seronegative, of whom 26.8% had a history of unsafe abortion. In Malawi and Pakistan all girls were seropositive and in Pakistan, following a booster vaccination, titres increased 3-fold, with a lower response in older girls. The results indicated that adequate childhood immunization is likely to provide protective levels through adolescence. Booster vaccination in late childhood/early adolescence should protect the majority of women throughout their reproductive lives. This practice would reduce the risks of girls exposed to infection through unsafe abortions, and may be the best option for countries seeking to improve their vaccination schedule, especially where tetanus vaccine coverage in pregnant women is unacceptably low.

A real-time volumetric visualization system for electrical impedance tomography.

Three dimensional (3D) electrical impedance tomography (EIT) presents many additional challenges over and above those associated with two dimensional EIT systems. With present two dimensional (2D) systems, tomographs can be reconstructed and displayed on a PC with a standard computer monitor. In addition, using appropriate data acquisition hardware and simple image reconstruction algorithms, it is possible to collect, reconstruct and display volumetric EIT images in real time using parallel processing architectures. The advantages of this 'real-time' capability are many and include the ability to immediately assess the correct functioning of the system and the ability to track patient events and the effect of procedures in real time. Whilst 3D EIT boundary datasets can be collected in real time, their real-time image reconstruction and display presents some computational challenges. This explains why, to date, no real-time solutions have been presented. In addition the use of a standard computer monitor to display 3D volumes is unsatisfactory since not all depth cues are preserved when using this type of 2D display device. We present a system which is capable of displaying 3D EIT datasets in real time and allows interactive modification of the user's viewpoint. This allows the user to fly around (and through) the EIT volumetric dataset.

Anatomical and physiological models for surgical simulation.

A considerable amount of effort has been aimed towards developing real-time deformable objects for surgical simulation, but very little work has been aimed towards including physiology within the soft tissue models. A simulator that links the structural and functional aspects of the human body would allow the user to develop a better understanding of the intrinsic link between anatomy and physiology. This positional paper discusses the challenges facing the creation of and the development of an integrated physiological and anatomical soft tissue model for use in surgical simulators. It explores the artificial dichotomy between anatomy and physiology and the issues it raises, by considering a suturing simulator capable of modelling ischaemia.

A birthweight nomogram for Africa, as a malaria-control indicator.

Low birthweight (LBW) attributable to malaria in pregnancy is a significant risk for millions in Africa. Infants born to primigravidae are at greatest risk and it is proposed that this excess risk can be used as a simple indicator of malaria transmission and exposure in pregnant women in Africa. Birthweight data from different regions in 11 malarious and three non-malarious African countries were investigated. A regression analysis of the excess risk of low birthweight in first pregnancies, compared with later ones, was completed and interpreted in relation to malaria-transmission intensities. The aim was to develop a simple birthweight chart (nomogram) as a tool for monitoring malaria transmission or malaria control in pregnancy. Low-birthweight risk in first pregnancies was associated with levels of malaria-transmission intensity amongst different African countries. The nomogram distinguished longitudinal changes in malaria exposure, related to season and changes in antimalarial-drug policy. Malaria is one of the most important causes of LBW in first pregnancies in Africa. As birthweight and parity are routinely recorded in many delivery centres across Africa, the nomogram provides a simple, available and inexpensive tool for monitoring malaria transmission and exposure in pregnant women and the effectiveness of malaria-control activities for this high-risk group.

Clinical experience with a new solvent detergent-treated intravenous immunoglobulin free of hypotensive effects.

OBJECTIVE: To see if modifications to the processing of intravenous immunoglobulin to include a virus inactivation stage alter immunoglobulin G (IgG) resulting in hypotension in patients. METHODS: Clinical trials were done involving extensive patient monitoring during infusion: in vitro - testing for markers of hypotension, and in vivo - an animal model which closely simulates clinical use. RESULTS: No hypotensive response was seen in the animal model or clinical trial. CONCLUSIONS: The production process used does not damage IgG or create vaso-active kinins as the preparation was free of hypotensive effects.