The effect of wearing loupes on upper extremity musculoskeletal disorders among dental hygienists

OBJECTIVES

It is well established that musculoskeletal disorders (MSD) are a significant occupational health issue for dentists and hygienists. Despite this, there has been little advancement in the application of ergonomic principles in the dental profession. While the use of loupes is often promoted as an ergonomic solution, there is little published research to robustly support this claim. The aim of the present study was to investigate the effect of the use of loupes on upper extremity MSD among dental hygienists.

METHODS

The study was conducted using an exploratory pretest and post-test design, comparing musculoskeletal measures in practising dental hygienists wearing loupes with final-year dental hygiene students who did not wear loupes. Pre- and post-test measures included valid self-reported and objective outcome measures and were measured at baseline and 6 months following the intervention. Statistical analysis was conducted as a series of mixed anovas with time and treatment as the independent variables.

RESULTS

The analysis revealed a significant interaction between time and treatment for the Disabilities of the Shoulder, Arm and Hand (DASH) scores (P < 0.04), indicating an improvement in symptoms for the treatment group but a reversed trend for the controls. There was also a significant mean increase in scapular position measures; however, this finding was evident in both groups, indicating that these were not a result of the intervention.

CONCLUSIONS

Overall, this study suggests that wearing loupes appears to have both positive and negative effects on upper extremity MSD among dental hygienists. Ongoing research is required to determine the long-term effects of loupes wear, over an extended period of time.

Inconsolable infant crying and maternal postpartum depressive symptoms

OBJECTIVE

To quantify the extent to which maternal report of inconsolable infant crying, rather than colic (defined by Wessel's criteria of daily duration of fussing and crying >3 hours), is associated with maternal postpartum depressive symptoms.

METHODS

Participants were 587 mothers who were recruited shortly before or after delivery and followed longitudinally. At 5 to 6 weeks postpartum, mothers recorded the duration and mode (fussing, crying, or inconsolable crying) of their infant's distress by using the Baby's Day Diary. The Edinburgh Postnatal Depression Scale (EPDS) was administered at enrollment and at 8 weeks postpartum. Using regression models that included baseline EPDS scores and multiple confounders, we examined associations of colic and inconsolable crying with later maternal EPDS scores at 8 weeks postpartum.

RESULTS

Sixty mothers (10%) met the EPDS threshold for "possible depression" (score ≥9) at 8 weeks postpartum. For mothers reporting >20 minutes of inconsolable crying per day, the adjusted odds ratio for an EPDS score ≥9 was 4.0 (95% confidence interval: 2.0-8.1), whereas the adjusted odds ratio for possible depression in mothers whose infants had colic was 2.0 (95% confidence interval: 1.1-3.7). These associations persisted after adjusting for baseline depression symptoms.

CONCLUSIONS

Maternal report of inconsolable infant crying may have a stronger association with postpartum depressive symptoms than infant colic. Asking a mother about her ability to soothe her infant may be more relevant for potential intervention than questions about crying and fussing duration alone.

Application of a novel microtitre plate-based assay for the discovery of new inhibitors of DNA gyrase and DNA topoisomerase VI

DNA topoisomerases are highly exploited targets for antimicrobial drugs. The spread of antibiotic resistance represents a significant threat to public health and necessitates the discovery of inhibitors that target topoisomerases in novel ways. However, the traditional assays for topoisomerase activity are not suitable for the high-throughput approaches necessary for drug discovery. In this study we validate a novel assay for screening topoisomerase inhibitors. A library of 960 compounds was screened against Escherichia coli DNA gyrase and archaeal Methanosarcina mazei DNA topoisomerase VI. Several novel inhibitors were identified for both enzymes, and subsequently characterised in vitro and in vivo. Inhibitors from the M. mazei topoisomerase VI screen were tested for their ability to inhibit Arabidopsis topoisomerase VI in planta. The data from this work present new options for antibiotic drug discovery and provide insight into the mechanism of topoisomerase VI.

Population pharmacokinetics of epsilon-aminocaproic acid in infants undergoing craniofacial reconstruction surgery

BACKGROUND

Understanding the clinical pharmacology of the antifibrinolytic epsilon-aminocaproic acid (EACA) is necessary for rational drug administration in children. The aim of this study is to determine the pharmacokinetics (PKs) of EACA in infants aged 6-24 months undergoing craniofacial reconstruction surgery.

METHODS

Cohorts of six infants were enrolled sequentially to one of the three escalating loading dose-continuous i.v. infusion (CIVI) regimens: 25 mg kg(-1), 10 mg kg(-1) h(-1); 50 mg kg(-1), 20 mg kg(-1) h(-1); 100 mg kg(-1), 40 mg kg(-1) h(-1). Plasma EACA concentrations were determined using a validated high-performance liquid chromatography-tandem mass spectrometry assay. A population non-linear mixed effects modelling approach was used to characterize EACA PKs.

RESULTS

Population PK parameters of EACA were estimated using a two-compartment disposition model with weight expressed as an allometric covariate and an age effect. The typical patient in this study had an age of 38.71 weeks and a weight of 8.82 kg. PK parameters for this typical patient were: pre-/postoperative plasma drug clearance of 32 ml min(-1) (3.6 ml kg(-1) min(-1)), inter-compartmental clearance of 42.4 ml min(-1) (4.8 ml min(-1) kg(-1)), central volume of distribution of 1.27 litre (0.14 litre kg(-1)), and peripheral volume of distribution of 2.53 litre (0.29 litre kg(-1)). Intra-operative clearance and central volume of distribution were 89% and 80% of the pre-/postoperative value, respectively.

CONCLUSIONS

EACA clearance increased with weight and age. The dependence of clearance on body weight supports weight-based dosing. Based on this study, a loading dose of 100 mg kg(-1) followed by a CIVI of 40 mg kg(-1) h(-1) is appropriate to maintain target plasma EACA concentrations in children aged 6-24 months undergoing these procedures.

Abstract P3-08-03: Urinary levels of prostaglandin E2 metabolite and postmenopausal breast cancer

Estrogens are considered a key player in the mammary carcinogenesis. In postmenopausal women, peripheral aromatization of androgens is the predominant source of estrogens. Given that prostaglandin E2 (PGE2) is a potent activator of aromatase expression, we hypothesized that endogenous level of PGE2 would influence estrogen bioavailability and subsequent breast cancer risk in postmenopausal women. In addition, because PGE2 synthesis is suppressed by treatment of non-steroidal anti-inflammatory drugs (NSAIDs) via inhibition of cyclooxygenase enzyme activity, we further hypothesized that regular use of NSAIDs may modify the association between PGE2 and postmenopausal breast cancer risk. We carried out a case-cohort analysis within the NIEHS Sister Study, a prospective cohort study of 50,884 women. Postmenopausal women who were aged 50 or older and did not report current use of hormones were eligible for the present analysis (N = 11,338). Urinary levels of a major PGE2 metabolite (PGE-M), which is generally accepted as the most accurate index of endogenous PGE2 formation, were quantified using liquid chromatography/tandem mass spectrometry in 302 incident breast cancer cases and 305 subcohort members who were randomly selected by frequency matching for age among cases. Hazard ratios (HR) and 95% confidence intervals (95% CI) were estimated using Prentice's pseudo-likelihood approach with Barlow's weighting scheme. Several factors were associated with higher levels of urinary PGE-M in the multivariable analysis, including current smoking, obesity, high caloric intake from saturated fat and surgical menopause. No associations were observed for dietary intake of omega 3 fatty acids, use of vitamin supplements and physical activity. Overall, there was no association between urinary PGE-M and postmenopausal breast cancer risk. After including the interaction terms between NSAID use and urinary levels of PGE-M in the model, however, high levels of urinary PGE-M were associated with an increased risk of breast cancer in postmenopausal women who did not regularly use NSAIDs (likelihood ratio test p &lt;0.01).

Choriophobia: a 1-act play

The management of a newborn born to a mother with chorioamnionitis is controversial. By using data collected on neonates born in the era of routine maternal screening for Group B Streptococcus, we calculate that the risk of early-onset sepsis in a hypothetical infant born at term to a mother with chorioamnionitis, who has a normal physical examination at birth, is likely substantially <1% if the mother's screen for Group B Streptococcus was negative. This low rate of sepsis calls into question current guidelines recommending treatment of all such newborns with intravenous antibiotics for 48 hours pending the results of a blood culture. Current guidelines for the management of infants born to mothers with chorioamnionitis also raise an important ethical issue; the recommendation to treat these infants with intravenous antibiotics is, in essence, a de facto determination of what constitutes unacceptable risk to the newborn. We argue that this determination is ultimately value-based and therefore requires broader deliberation than that which frequently occurs among medical experts who develop medical guidelines.

High-throughput microtitre plate-based assay for DNA topoisomerases

We have developed a rapid, high-throughput assay for measuring the catalytic activity (DNA supercoiling or relaxation) of DNA topoisomerases. The assay utilizes intermolecular triplex formation between an immobilized triplex-forming oligo (TFO) and a triplex-forming region inserted into the plasmid substrate (pNO1), and capitalizes on the observation that supercoiled DNA forms triplexes more readily than relaxed DNA. Thus, supercoiled DNA is preferentially retained by the TFO under triplex-forming conditions while relaxed DNA can be washed away. Due to its high speed of sample analysis and reduced sample handling over conventional gel-based techniques, this assay can be used to screen chemical libraries for novel inhibitors of topoisomerases.

Characterizing providers' immunization communication practices during health supervision visits with vaccine-hesitant parents: a pilot study

OBJECTIVE

To determine the feasibility of using direct observation of provider-parent immunization discussions and to characterize provider communication practices with vaccine-hesitant parents.

METHODS

Over a 6 month period in 2010, we videotaped immunization discussions between pediatric providers and vaccine-hesitant parents during health supervision visits involving children 2-15 months old (N=24) in the Seattle area, Washington, USA. Videotapes were analyzed using the qualitative method of conversation analysis.

RESULTS

We approached 96 parents seen by 9 different providers. Of those who were eligible (N=56), we enrolled 43% (N=24). Four videotaped visits were excluded from analysis for failure to obtain parental HIPAA authorization. Of the remaining 20 visits, there were ≥2 visits each that involved children aged 2, 4, 6, 9, 12, and 15 months, and all videotaped visits contained at least a brief immunization discussion. We identified 6 communication practices and several behavior types within each practice relevant to immunization: Practice 1, providers' initiations of the topic of vaccination; Types: participatory or presumptive format; Practice 2, parents' responses to providers' topic initiations; Types: strong or weak acceptance or resistance; Practice 3, providers' follow-ups to parent's responses; Types: no, immediate, or delayed pursuit; Practice 4, parents' vaccine-related questions or statements; Types: fact- or concern-based; Practice 5, providers' explicit solicitations of parent's questions/concerns; Types: designed to discourage or encourage discussion; and Practice 6, parents' responses to providers' solicitations of questions/concerns; Types: no question or fact- or concern-based inquiry.

CONCLUSION

Direct observation of immunization discussions in the primary care pediatric setting is feasible and yields insight into several provider-parent immunization communication practices that are worthy of further study to determine which are effective at improving parental acceptance of immunization.

Homeopathic ear drops as an adjunct to standard therapy in children with acute otitis media

OBJECTIVE

To assess the effectiveness of a homeopathic ear drop for treatment of otalgia in children with acute otitis media (AOM).

METHODS

Children with AOM were enrolled in the study at the time of diagnosis and randomized to receive either standard therapy alone or standard therapy plus a homeopathic ear drop solution that was to be used on as needed basis for up to 5 days. Parents of children in both treatment groups rated the severity of 5 AOM symptoms twice daily for 5 days in a symptom diary. A symptom score was computed for each assessment with lower scores denoting less severe symptoms. Parents of children randomized to receive ear drops also recorded information regarding symptoms being treated and response to treatment.

RESULTS

A total of 119 eligible children were enrolled in the study; symptom diaries were received from 94 (79%). Symptom scores tended to be lower in the group of children receiving ear drops than in those receiving standard therapy alone; these differences were significant at the second and third assessments (P = 0.04 and P = 0.003, respectively). In addition, the rate of symptom improvement was faster in children in the ear drop group compared with children in standard therapy alone group (P = 0.002). The most common reason for administration of ear drops was ear pain, recorded for 93 doses; improvement was noted after 78.4% of doses for this indication. There were no significant side effects related to use of the ear drops.

CONCLUSIONS

This study suggests that homeopathic ear drops were moderately effective in treating otalgia in children with AOM and may be most effective in the early period after a diagnosis of AOM. Pediatricians and other primary health care providers should consider homeopathic ear drops a useful adjunct to standard therapy.

Washington State pediatricians' attitudes toward alternative childhood immunization schedules

OBJECTIVE

To determine the frequency of parents' requests for alternative childhood immunization schedules (ACISs) and pediatricians' comfort with and willingness to use ACISs.

METHODS

Washington State primary care pediatricians were asked to complete an Internet-based survey on ACISs. The main outcome measures were the frequency of parents' requests for ACISs, pediatricians' comfort with their use, and pediatricians' willingness to use ACISs for individual vaccines. In addition, respondents were asked to characterize their practices and to provide demographic information.

RESULTS

Of the 311 respondents (response rate: 65%), 209 met inclusion criteria and were included in analyses. Overall, 77% of eligible respondents reported that parents sometimes or frequently requested ACISs, and 61% were comfortable using an ACIS if requested by a parent. Pediatricians were least willing to consider using ACISs for diphtheria-tetanus toxoids-acellular pertussis vaccine, Haemophilus influenzae type b vaccine, and pneumococcal conjugate vaccine. Pediatricians who practiced in a neighborhood or community clinic were less comfortable using ACISs than were those in a 1- or 2-physician practice (odds ratio: 0.10).

CONCLUSIONS

Washington State pediatricians are regularly being asked to use ACISs, and most of them are comfortable using them if requested. Pediatricians are least willing to delay H influenzae type b vaccine, diphtheria-tetanus toxoids-acellular pertussis vaccine, and pneumococcal conjugate vaccine, which suggests prioritization of immunizations that protect against potentially devastating bacterial infections of infancy and early childhood.

The Caulobacter crescentus chromosome replication origin evolved two classes of weak DnaA binding sites

The Caulobacter crescentus replication initiator DnaA and essential response regulator CtrA compete to control chromosome replication. The C. crescentus replication origin (Cori) contains five strong CtrA binding sites but only two apparent DnaA boxes, termed G-boxes (with a conserved second position G, TGATCCACA). Since clusters of DnaA boxes typify bacterial replication origins, this discrepancy suggested that C. crescentus DnaA recognizes different DNA sequences or compensates with novel DNA-binding proteins. We searched for novel DNA sites by scanning mutagenesis of the most conserved Cori DNA. Autonomous replication assays showed that G-boxes and novel W-boxes (TCCCCA) are essential for replication. Further analyses showed that C. crescentus DnaA binds G-boxes with moderate and W-boxes with very weak affinities significantly below DnaA's capacity for high-affinity Escherichia coli-boxes (TTATCCACA). Cori has five conserved W-boxes. Increasing W-box affinities increases or decreases autonomous replication depending on their strategic positions between the G-boxes. In vitro, CtrA binding displaces DnaA from proximal G-boxes and from distal W-boxes implying CtrA-DnaA competition and DnaA-DnaA cooperation between G-boxes and W-boxes. Similarly, during cell cycle progression, CtrA proteolysis coincides with DnaA binding to Cori. We also observe highly conserved W-boxes in other replication origins lacking E. coli-boxes. Therefore, strategically weak DnaA binding can be a general means of replication control.

Development of a survey to identify vaccine-hesitant parents: the parent attitudes about childhood vaccines survey

OBJECTIVE

To develop a survey to accurately assess parental vaccine hesitancy.

RESULTS

The initial survey contained 17 items in four content domains: (1) immunization behavior; (2) beliefs about vaccine safety and efficacy; (3) attitudes about vaccine mandates and exemptions; and (4) trust. Focus group data yielded an additional 10 survey items. Expert review of the survey resulted in the deletion of nine of 27 items and revisions to 11 of the remaining 18 survey items. Parent pretesting resulted in the deletion of one item, the addition of one item, the revision of four items, and formatting changes to enhance usability. The final survey contains 18 items in the original four content domains.

METHODS

An iterative process was used to develop the survey. First, we reviewed previous studies and surveys on parental health beliefs regarding vaccination to develop content domains and draft initial survey items. Focus groups of parents and pediatricians generated additional themes and survey items. Six immunization experts reviewed the items in the resulting draft survey and ranked them on a 1-5 scale for significance in identifying vaccine-hesitant parents (5 indicative of a highly significant item). The lowest third of ranked items were dropped. The revised survey was pretested with 25 parents to assess face validity, usability and item understandability.

CONCLUSIONS

The Parent Attitudes about Childhood Vaccines survey was constructed using qualitative methodology to identify vaccine-hesitant parents and has content and face validity. Further psychometric testing is needed.

The utility of alkaline phosphatase measurement as a screening test for rickets in breast-fed infants and toddlers: a study from the puget sound pediatric research network

To determine if alkaline phosphatase (AP) levels are a useful screening test for rickets, the authors measured serum AP levels in children 6 to 15 months old who were predominantly breast-fed for > 6 months without vitamin D supplementation. Radiographs were obtained on children with elevated AP levels to determine the presence of rickets. AP levels were obtained on 246 children; levels were elevated in 33 (13.4%). Rickets was present in 4 of 18 children with elevated levels on whom radiographs were obtained. The sensitivity and specificity of AP levels as a test for rickets was maximal at a cutoff value of 552 U/L. Using this cutoff value, the specificity of AP levels as a test for rickets was 97.4%, and the positive predictive value (PPV) was 40.0%. These results suggest that AP levels may be a useful screening test for rickets in children who are breast-fed for prolonged periods without vitamin D supplementation.

14 nights of intermittent hypoxia elevate daytime blood pressure and sympathetic activity in healthy humans

Obstructive sleep apnoea syndrome (OSAS) causes nocturnal chronic intermittent hypoxia (IH) that contributes to excess cardiovascular morbidity. To explore the consequences of IH, we used our recently developed model of nocturnal IH in healthy humans to characterise the profile of this blood pressure increase, to determine if it is sustained and to explore potential physiological mechanisms. We performed 24-h ambulatory monitoring of blood pressure in 12 healthy subjects before and after 2 weeks of IH exposure. We also assessed systemic haemodynamics, muscle sympathetic nerve activity (MSNA), ischaemic calf blood flow responses and baroreflex gain. We obtained blood samples for inflammatory markers before, during and after exposure. IH significantly increased daytime ambulatory blood pressure after a single night of exposure (3 mmHg for mean and diastolic) and further increased daytime pressures after 2 weeks of exposure (8 mmHg systolic and 5 mmHg diastolic). Mean ± sd MSNA increased across the exposure (17.2 ± 5.1 versus 21.7 ± 7.3 bursts·min⁻¹; p < 0.01) and baroreflex control of sympathetic outflow declined from -965.3 ± 375.1 to -598.4 ± 162.6 AIU·min⁻¹ ·mmHg⁻¹ (p < 0.01). There were no evident changes in either vascular reactivity or systemic inflammatory markers. These data are the first to show that the arterial pressure rise is sustained throughout the waking hours beyond the acute phase immediately after exposure. Moreover, they may suggest that sympathoactivation induced by IH likely contributes to blood pressure elevation and may derive from reduced baroreflex inhibition. These mechanisms may reflect those underlying the blood pressure elevation associated with OSAS.

The BAM complex subunit BamE (SmpA) is required for membrane integrity, stalk growth and normal levels of outer membrane {beta}-barrel proteins in Caulobacter crescentus

The outer membrane of Gram-negative bacteria is an essential compartment containing a specific complement of lipids and proteins that constitute a protective, selective permeability barrier. Outer membrane beta-barrel proteins are assembled into the membrane by the essential hetero-oligomeric BAM complex, which contains the lipoprotein BamE. We have identified a homologue of BamE, encoded by CC1365, which is located in the outer membrane of the stalked alpha-proteobacterium Caulobacter crescentus. BamE associates with proteins whose homologues in other bacteria are known to participate in outer membrane protein assembly: BamA (CC1915), BamB (CC1653) and BamD (CC1984). Caulobacter cells lacking BamE grow slowly in rich medium and are hypersensitive to anionic detergents, some antibiotics and heat exposure, which suggest that the membrane integrity of the mutant is compromised. Membranes of the DeltabamE mutant have normal amounts of the outer membrane protein RsaF, a TolC homologue, but are deficient in CpaC*, an aggregated form of the outer membrane secretin for type IV pili. Delta bamE membranes also contain greatly reduced amounts of three TonB-dependent receptors that are abundant in wild-type cells. Cells lacking BamE have short stalks and are delayed in stalk outgrowth during the cell cycle. Based on these findings, we propose that Caulobacter BamE participates in the assembly of outer membrane beta-barrel proteins, including one or more substrates required for the initiation of stalk biogenesis.