Outcomes of Injection Laryngoplasty for Deep Interarytenoid Groove

Introduction  Deep interarytenoid groove (DIG) may cause swallowing dysfunction in children; however, the management of DIG has not been established. Objective  We evaluated the subjective and objective outcomes of interarytenoid augmentation with injection in children with DIG. Methods  Consecutive children under 18 years of age who underwent injection laryngoplasty for DIG were reviewed. Data pertaining to demographics, past medical history, past surgical history, and results of pre and postoperative video fluoroscopic swallow study (VFSS) were obtained. The primary outcome measure was the presence of thin liquid aspiration or penetration on postoperative VFSS. The secondary outcome measure was caregiver-reported improvement of symptoms. Results  Twenty-seven patients had VFSS before and after interarytenoid augmentation with injection (IA). Twenty (70%) had thin liquid penetration and 12 (44%) had thin liquid aspiration before the IA. Thin liquid aspiration resolved in 9 children (45%) and persisted in 11 (55%). Of the 12 children who had thin liquid aspiration prior to IA, 6 (50%) had resolution of thin liquid aspiration after IA. Conclusions  Injection laryngoplasty is a safe tool to improve swallowing function in children with DIG. Further studies are needed to assess the long-term outcomes of IA and identify predictors of successful IA in children with DIG.

Survival After Declining Pediatric Tracheostomy Placement

OBJECTIVE

To determine survival among critically ill children when caregivers decline tracheostomy placement.

STUDY DESIGN

Retrospective cohort.

METHODS

All children (<18 years) obtaining a pre-tracheostomy consultation at a tertiary children's hospital between 2016 and 2021 were included. Comorbidities and mortality were compared between children of caregivers that declined or agreed to tracheostomy.

RESULTS

Tracheostomy was declined for 58 children but was placed for 203 children. After consultation, mortality was 52% (30/58) when declining and 21% (42/230) when agreeing to tracheostomy (p < 0.001) at a mean of 10.7 months (standard deviation [SD]: 16) and 18.1 months (SD: 17.1), respectively (p = 0.07). For those declining, 31% (18/58) died during the hospitalization within a mean of 1.2 months (SD: 1.4) while 21% (12/58) died at a mean of 23.6 months (SD: 17.5) after discharge. Among children of caregivers declining tracheostomy, older age (odds ratio [OR]: 0.85, 95% confidence interval [CI]: 0.74-0.97, p = 0.01) and chronic lung disease (OR: 0.18, 95% CI: 0.04-0.82, P = .03) were associated with lower odds of mortality but sepsis (OR: 9.62, 95% CI: 1.161-57.43, p = 0.01) and intubation (OR: 4.98, 95% CI: 1.24-20.08, p = 0.02) were associated with higher odds of mortality. Median survival after declining tracheostomy was 31.9 months (interquartile range [IQR]: 2.0-50.7) and declining placement was associated with increased mortality risk (hazard ratio [HR]: 4.04, 95% CI: 2.49-6.55, p < 0.001).

CONCLUSION

When caregivers declined tracheostomy placement, less than half of critically ill children in this cohort survived with younger age, sepsis, and intubation associated with higher mortality. This information offers valuable insight for families weighing decisions pertaining to pediatric tracheostomy placement.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3602-3607, 2023.

Accidental Tracheostomy Decannulations in Children-A Prospective Cohort Study of Inpatients

OBJECTIVES

To determine the incidence of tracheostomy accidental decannulations (AD) among pediatric inpatients and identify risks for these events.

STUDY DESIGN

Prospective cohort.

METHODS

All tracheostomy patients (≤18 years) admitted at a tertiary children's hospital between August 2018 and April 2021 were included. AD were recorded and patient harm was classified as no harm/minor, moderate, or severe. Monthly AD incidence was described as events per 1000 tracheostomy-days.

RESULTS

One-hundred seventeen AD occurred among 67 children with 33% (22/67) experiencing multiple events (median: 2.5 events, range: 2-10). Mean age at AD was 4.7 years (SD: 4.4). AD resulted from patient movement (32%, 37/117), performing tracheostomy care (27%, 31/117), repositioning or transporting (15%, 17/117), or unclear reasons (27%, 32/117). A parent or guardian was involved in 28% (33/117) of events. Nearly all AD resulted in no more than minor harm (84%, 98/117) but moderate (12%, 14/117) and severe (4%, 5/117) events did occur. There were no deaths. Tracheostomy care or repositioning were frequently responsible in acute versus subacute events (48% vs. 26%, p = 0.04). Mean monthly AD incidence was 4.7 events per 1000 tracheostomy-days (95% CI: 3.7-5.8) and after implementation of safety initiatives, the mean rate decreased from 5.9 events (95% CI: 4.2-7.7) to 3.7 events (95% CI: 2.5-5.0) per 1000 tracheostomy-days (p = 0.04).

CONCLUSIONS

AD in children occur at nearly 5 events per 1000 tracheostomy-days and often result in minimal harm. Quality initiatives targeting patient movement, provider education, and tracheostomy care might reduce the frequency of these complications.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:963-969, 2023.

Mortality Among Children with a Tracheostomy

OBJECTIVES

To characterize the cause of death among children with a tracheostomy.

STUDY DESIGN

Prospective cohort.

METHODS

All pediatric patients (<18 years) who had a tracheostomy placed at a tertiary care institution between 2015 and 2020 were included. The location and cause of death were recorded along with patient demographics and age.

RESULTS

A total of 271 tracheostomies were placed with 46 mortalities reviewed for a mortality rate of 16.8%. Mean age at placement was 1.7 years (SD: 3.4) and mean age at death was 2.9 years (SD: 3.5). Most tracheostomies were placed for respiratory failure (N = 33, 72%). The mean time to death after tracheostomy was 1.2 years (SD: 1.2) and 28% (N = 13) occurred during the same admission as placement. Mean time to death after hospital discharge was 1.3 years (SD: 1.3). Etiology of death was respiratory failure (33%, N = 15), cardiopulmonary arrest (15%, N = 7), unknown (43%, N = 20), or secondary to a tracheostomy-related complication for 9% (N = 4). Location of death was in intensive care units for 41% (N = 19) and 30% died at home (N = 14). Comfort care measures were taken for 37% (N = 17). Severe neurological disability (HR: 4.06, p = 0.003, 95% CI: 1.59-10.34) and congenital heart disease (HR: 2.36, p = 0.009, 95% CI: 1.24-4.48) correlated with time to death on Cox proportional hazard modeling.

CONCLUSIONS

Nearly one-third of children with a tracheostomy who expire will do so during the same admission as tracheostomy placement. Although progression of underlying disease will lead to most deaths, 9% will be a result of a tracheostomy-related complication, which represents a meaningful target for quality improvement initiatives.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:403-409, 2023.

Caregiver quality of life after pediatric tracheostomy

OBJECTIVE

To determine the impact of a child with a tracheostomy on caregiver quality of life.

METHODS

A repeated cross-sectional analysis included families with tracheostomy-dependent children between 2019 and 2021. Caregivers were surveyed using the PedsQL™ Family Impact Module with assessments at tracheostomy placement and during ambulatory office visits.

RESULTS

Two-hundred and fifty-five surveys were performed with 66 at tracheostomy placement (26%) and 189 at follow-up visits (74%). Compared to families with healthy children, total scores at placement (77.2 vs. 87.6, P < .001) and follow-up visits (78.9 vs. 87.6, P < .001) were significantly lower among pediatric tracheostomy families. Caregivers were likely to report significant improvement in emotional functioning (6.2 points; 95% CI: 0.5-12, P = .03) and worry (9 points, 95% CI: 2.1-15.9, P = .01) over time. Demographic variables demonstrated no confounding or interactive effects.

CONCLUSIONS

The presence of a tracheostomy is associated with lower caregiver quality of life scores in the short- and long-term compared to caregivers of healthy children. Providers should be sensitive to these challenges and provide appropriate support for families of tracheostomy-dependent children.

Pediatric Tracheostomy Outcomes After Development of a Multidisciplinary Airway Team: A Quality Improvement Initiative

Objectives

To analyze a multidisciplinary tracheostomy team's effect on length of stay and cost.

Methods

An airway management program using a balanced scorecard was created to track key performance measures. Interventions included weekly rounding, standardized placement, postoperative care, and caregiver education. Process measures included time to first education, speech-language pathology consultation rates, and pretracheostomy consultations. Outcome measures focused on the total length of stay, 30-day revisit rates after discharge, accidental decannulation rate, and standardized cost. Regression analysis was used to predict the program's effect on length of stay and total cost.

Results

In total, 239 children met inclusion. The mean time to first education class was reduced from 13.7 to 1.9 days (P < .001). The speech-language pathology consultation rate increased from 68% to 95% (P < .001), and the presurgical consultation rate with the tracheostomy team increased from 14% to 93% (P < .001). The length of stay decreased from 133 to 96 days (P = .006). Total costs were lower for short admissions but higher for prolonged admissions. Revisits within 30 days remained stable over time (18%).

Discussion

Establishing a multidisciplinary tracheostomy team results in improvements in quality metrics when caring for children with tracheostomies. Controlling for associated factors showed the mean length of stay decreased significantly in the first full year of program implementation. Cost analysis estimated significant reductions for tracheostomy patients spending less time in the hospital.

Implications for Practice

A airway management program can positively affect tracheostomy processes and outcomes.

Recovery of Vocal Cord Motion Among Pediatric Patients

OBJECTIVES

Patients with vocal cord paralysis can experience feeding, respiratory, and vocal problems leading to disability and decreased quality of life. Current evidence suggests waiting a period of 12 months for spontaneous recovery before permanent interventions. This study aims to determine the time to recover spontaneously and vocal cord movement in a pediatric population and create a model for evidence-based patient counseling.

STUDY DESIGN

Retrospective longitudinal cohort study.

METHODS

The report is a single institution longitudinal study on vocal cord paralysis recovery. Patients were categorized based on spontaneous recovery with vocal cord movement or no recovery. Recovery rates were determined using the Kaplan-Meier method.

RESULTS

Of 158 cases of vocal cord paralysis over a 4-year period, 36 had spontaneous recovery with symptom improvement and motion return. The average recovery was 8.8 months for those who recovered, and 78% recovered within 9 months. Two groups emerged from the data: an early recovery group with spontaneous recovery before 12 months and a late recovery group after 12 months. Children with dysphonia and paralysis due to cardiac surgery were less likely to recover, and children with aspiration were more likely to recover. Children with gastrointestinal comorbidities were less likely to recover; however, those who did recover were more likely to have recovered after 12 months. Based on our model, there is about a 3% chance of recovery between 9 and 12 months.

CONCLUSIONS

Patients should be counseled about earlier interventions. Waiting the conventional 12 months for only a 3% chance of spontaneous recovery without intervention or laryngeal EMG may not be the preferred option for some patients and their families.

Recommendations for locus-specific databases and their curation

Expert curation and complete collection of mutations in genes that affect human health is essential for proper genetic healthcare and research. Expert curation is given by the curators of gene-specific mutation databases or locus-specific databases (LSDBs). While there are over 700 such databases, they vary in their content, completeness, time available for curation, and the expertise of the curator. Curation and LSDBs have been discussed, written about, and protocols have been provided for over 10 years, but there have been no formal recommendations for the ideal form of these entities. This work initiates a discussion on this topic to assist future efforts in human genetics. Further discussion is welcome.

A structured simple form for ordering genetic tests is needed to ensure coupling of clinical detail (phenotype) with DNA variants (genotype) to ensure utility in publication and databases

Researchers and clinicians ideally need instant access to all the variation in their gene/locus of interest to efficiently conduct their research and genetic healthcare to the highest standards. Currently much key data resides in the laboratory books or patient records around the world, as there are many impediments to submitting this data. It would be ideal therefore if a semiautomated pathway was available, with a minimum of effort, to make the deidentified data publicly available for others to use. The Human Variome Project (HVP) meeting listed 96 recommendations to work toward this situation. This article is planned to initiate a strategy to enhance the collection of phenotype and genotype data from the clinician/diagnostic laboratory nexus. Thus, the aim is to develop universally applicable forms that people can use when investigating patients for each inherited disease, to assist in satisfying many of the recommendations of the HVP Meeting [Cotton et al., 2007]. We call for comment and collaboration in this article.

Ciguatera poisoning: a global issue with common management problems

Ciguatera poisoning, a toxinological syndrome comprising an enigmatic mixture of gastrointestinal, neurocutaneous and constitutional symptoms, is a common food-borne illness related to contaminated fish consumption. As many as 50000 cases worldwide are reported annually, and the condition is endemic in tropical and subtropical regions of the Pacific Basin, Indian Ocean and Caribbean. Isolated outbreaks occur sporadically but with increasing frequency in temperate areas such as Europe and North America. Increase in travel between temperate countries and endemic areas and importation of susceptible fish has led to its encroachment into regions of the world where ciguatera has previously been rarely encountered. In the developed world, ciguatera poses a public health threat due to delayed or missed diagnosis. Ciguatera is frequently encountered in Australia. Sporadic cases are often misdiagnosed or not medically attended to, leading to persistent or recurrent debilitating symptoms lasting months to years. Without treatment, distinctive neurologic symptoms persist, occasionally being mistaken for multiple sclerosis. Constitutional symptoms may be misdiagnosed as chronic fatigue syndrome. A common source outbreak is easier to recognize and therefore notify to public health organizations. We present a case series of four adult tourists who developed ciguatera poisoning after consuming contaminated fish in Vanuatu. All responded well to intravenous mannitol. This is in contrast to a fifth patient who developed symptoms suggestive of ciguatoxicity in the same week as the index cases but actually had staphylococcal endocarditis with bacteraemia. In addition to a lack of response to mannitol, clinical and laboratory indices of sepsis were present in this patient. Apart from ciguatera, acute gastroenteritis followed by neurological symptoms may be due to paralytic or neurotoxic shellfish poisoning, scombroid and pufferfish toxicity, botulism, enterovirus 71, toxidromes and bacteraemia. Clinical aspects of ciguatera toxicity, its pathophysiology, diagnostic difficulties and epidemiology are discussed.

Analysis of the study design and manuscript deficiencies in research articles submitted to Emergency Medicine

OBJECTIVE

To describe and analyse the study design and manuscript deficiencies in original research articles submitted to Emergency Medicine.

METHODS

This was a retrospective, analytical study. Articles were enrolled if the reports of the Section Editor and two reviewers were available. Data were extracted from these reports only. Outcome measures were the mean number and nature of the deficiencies and the mean reviewers' assessment score.

RESULTS

Fifty-seven articles were evaluated (28 accepted for publication, 19 rejected, 10 pending revision). The mean (+/- SD) number of deficiencies was 18.1 +/- 6.9, 16.4 +/- 6.5 and 18.4 +/- 6.7 for all articles, articles accepted for publication and articles rejected, respectively (P = 0.31 between accepted and rejected articles). The mean assessment scores (0-10) were 5.5 +/- 1.5, 5.9 +/- 1.5 and 4.7 +/- 1.4 for all articles, articles accepted for publication and articles rejected, respectively. Accepted articles had a significantly higher assessment score than rejected articles (P = 0.006). For each group, there was a negative correlation between the number of deficiencies and the mean assessment score (P > 0.05). Significantly more rejected articles ' em leader did not further our knowledge' (P = 0.0014) and ' em leader did not describe background information adequately' (P = 0.049). Many rejected articles had ' em leader findings that were not clinically or socially significant' (P = 0.07). Common deficiencies among all articles included ambiguity of the methods (77%) and results (68%), conclusions not warranted by the data (72%), poor referencing (56%), inadequate study design description (51%), unclear tables (49%), an overly long discussion (49%), limitations of the study not described (51%), inadequate definition of terms (49%) and subject selection bias (40%).

CONCLUSIONS

Researchers should undertake studies that are likely to further our knowledge and be clinically or socially significant. Deficiencies in manuscript preparation are more frequent than mistakes in study design and execution. Specific training or assistance in manuscript preparation is indicated.

Rheological characterization of bioadhesive, antimicrobial, semisolids designed for the treatment of periodontal diseases: transient and dynamic viscoelastic and continuous shear analysis

This study examined the creep behavior and oscillatory and flow properties of tetracycline-containing, bioadhesive semisolid formulations, designed for localized treatment of periodontal disease. Formulations were prepared containing hydroxyethylcellulose (HEC, 1, 3, or 5% w/w), poly(vinylpyrrolidone) (PVP, 2 or 3% w/w), polycarbophil (PC, 1 or 3% w/w), and tetracycline (5% w/w, as the hydrochloride). In creep analysis, each formulation exhibited several distinct regions that were mathematically modelled using a multi-element Voigt model with a residual spring and dashpot. Increasing the concentrations of each polymeric component decreased the elastic compliance (J(0)) yet increased the residual viscosity. In oscillatory analysis, increased polymer concentrations increased the storage modulus (G'), the loss modulus (G") and the dynamic viscosity (eta'), yet decreased the loss tangent (tan delta). The relationships between G' or G" and frequency were observed to plateau at higher frequencies, which is indicative of polymer chain entanglement and network formation. With the exception of formulations containing 1% HEC, the formulations were elastic (tan delta < 1), with large G' and small J(0) values. All formulations exhibited pseudoplastic flow with thixotropy. Increasing concentrations of each polymeric component increased the zero-shear viscosity (determined using the Cross model) and was further evidence of polymer chain entanglement. Formulations containing 1% w/w HEC possessed excellent flow properties, however, their thixotropic behavior and essentially elastoviscous nature (large J(0) and tan delta) would be disadvantageous for use in the treatment of periodontal disease because of rapid removal from the pocket and relatively uncontrolled drug release. Despite their advantageous viscoelastic properties, the flow properties of formulations containing 5% w/w HEC were inappropriate, rendering administration through a periodontal syringe potentially difficult. Based on their rheological behavior, formulations containing HEC (3% w/w), PVP (2 or 3% w/w), and PC (1 or 3% w/w) would be suitable for clinical application. However, consideration of other physicochemical properties (e.g., bioadhesion, drug release kinetics) must be performed prior to selection of the most suitable formulation for clinical examination. This study has highlighted the successful complimentary application of creep analysis and oscillatory and flow rheometry for the characterization and development of bioadhesive semisolid formulations for the treatment of periodontal disease.

Emergency department anaphylaxis: A review of 142 patients in a single year

BACKGROUND

There are few data on the incidence, clinical features, and management of patients with acute anaphylaxis presenting to the emergency department. We investigated all presentations to one department during the course of a year to improve current awareness of this medical emergency.

OBJECTIVE

The purpose of the study was to describe the clinical features, management, and outcome of anaphylaxis presentations to a single Australian adult emergency department in a single year, 1998-1999.

METHODS

This was a retrospective, case-based study of adult patients (>or=13 years of age) attending a single emergency department in Brisbane, Australia, during the year 1998-1999. The medical records of 304 patients satisfying the relevant discharge diagnostic codes were studied. We determined incidence, sex ratio, age, clinical features, management, disposal, asthma prevalence, and causes in patients presenting with acute allergic reactions and anaphylaxis.

RESULTS

In all, 162 emergency department patients with acute allergic reactions and 142 emergency department patients with anaphylaxis, including 60 whose anaphylaxis was severe, were seen during the year, for an anaphylaxis presentation incidence of 1 in 439. One patient died; this gave a case fatality rate of 0.70%. Cutaneous features were present in 94% of the patients with anaphylaxis. Of those with severe anaphylaxis, 35% had dizziness/syncope before hospital presentation, 25% laryngeal edema, and 21.7% systolic hypotension on hospital presentation. A cause was recognized in 73% of the anaphylaxis cases; most commonly, the causative agent was a drug, insect venom, or food. Adrenaline was used in 57% of the severe cases before hospital presentation or in the hospital. The emergency department alone definitively cared for 94% of all patients, though only 43% severe anaphylaxis cases were referred for follow-up.

CONCLUSION

The emergency department anaphylaxis presentation incidence of 1 in 439 cases is greater than previously recognized, though death remains rare. In three fourths of cases, a precipitant was identified, a fact that emphasizes the need for a detailed initial history. Definitive management in the emergency department alone is possible in most cases, provided that the appropriate use of adrenaline and the need for allergy clinic follow-up are appreciated.

Gene flow versus local adaptation in the northern acorn barnacle, Semibalanus balanoides: insights from mitochondrial DNA variation

In reciprocal transplant experiments, Bertness and Gaines (1993) found that Semibalanus balanoides juveniles that had settled in an upper Narragansett Bay estuary survived better in that estuary that did juveniles from coastal localities. The observed pattern of survivorship led to the claim that local adaptation may result from a combination of limited gene flow between and strong selection within these habitats. Here we test the hypothesis that limited gene flow has led to habitat-specific population differentiation using sequence and restriction fragment length polymorphism analyses of the mitochondrial DNA D-loop region of S. balanoides. Samples were analyzed from replicated coastal and estuary localities in both Narragansett Bay, Rhode Island, and Damariscotta River, Maine. The patterns of F(ST) indicate that gene flow between coast and estuary is extensive (Nm > 100) and is not lower in the estuary with lower flushing rates (Narragansett Bay). Given the high estimate of genetic exchange, adaptations for unpredictable environments seem more likely than local adaptation in this species because loci that respond to selection in one generation are essentially homogenized by the next seasons' settlement. Nevertheless, these estimates of neutral gene flow can help identify the strength of selection necessary for local adaptation to accumulate in Semibalanus.

Abdominal injury and the seat-belt sign

OBJECTIVE

To report on: 1. Prevalence of seat-belt sign in motor vehicle accident victims with abdominal injuries; 2. Prevalence of intestinal injuries in patients with seat-belt sign; and 3. Spectrum of abdominal injuries in a population with high usage of three-point restraints.

METHODS

A retrospective chart review was conducted in an adult tertiary-referral hospital from January 1992 to August 1998. Patients were identified from International Classification of Disease-9 codes for abdominal wall and intra-abdominal injuries.

RESULTS

The seat-belt sign was present in 60/99. The proportion of intestinal injuries in patients with and without seat-belt sign were 9/60 and 0/39, respectively (P = 0.01). In the 25 patients with intra-abdominal injuries, there were 10 hepatic, 8 splenic, 9 intestinal and 4 retroperitoneal injuries.

CONCLUSION

The seat-belt sign is indicative of an increased risk of intestinal injury, which is difficult to detect with no single test providing reliable diagnosis. Other intra-abdominal and retroperitoneal injuries may also occur, which are more readily diagnosed on computed tomography scan or focused abdominal utlrasound when available, but are no more frequent in patients with the seat-belt sign than those without.

Quantitative Trait Loci in Sweet Corn Associated with Partial Resistance to Stewart's Wilt, Northern Corn Leaf Blight, and Common Rust

ABSTRACT Partial resistance to Stewart's wilt (Erwina stewartii, syn. Pantoea stewartii), northern corn leaf blight (NCLB) (Exserohilum turcicum), and common rust (Puccinia sorghi) was observed in an F(2:3) population developed from a cross between the inbred sweet corn lines IL731a and W6786. The objective of this study was to identify quantitative trait loci (QTL) associated with partial resistance using restriction fragment length polymorphic markers. Phenotypic data were collected for 2 years for Stewart's wilt, NCLB, and common rust but, due to significant family-environment interaction, analysis was conducted individually on data from each year. In 2 years of evaluation for the three diseases, a total of 33 regions in the maize genome were associated with partial resistance describing from 5.9 to 18% of the total phenotypic variability. Of six regions common in both years, three were associated with partial resistance to Stewart's wilt (chromosomes 4:07, 5:03, and 6:04), one was associated with NCLB (chromosome 9:05), and two were associated with common rust (chromosomes 2:04 and 3:04). The rust QTL on 3S mapped to within 20 cM of the rp3 locus and explained 17.7% of the phenotypic variability. Some of the QTL associated with partial resistance to the three diseases have been reported previously, and some are described here for the first time. Results suggest it may be possible to consolidate QTL from various elite backgrounds in a manner analogous to the pyramiding of major resistance genes. We also report here on two QTL associated with anthocyanin production on chromosomes 10:6 and 5:03 in the general location of the a2 gene.

Design, characterisation and preliminary clinical evaluation of a novel mucoadhesive topical formulation containing tetracycline for the treatment of periodontal disease

This study describes the formulation, characterisation and preliminary clinical evaluation of mucoadhesive, semi-solid formulations containing hydroxyethylcellulose (HEC, 1-5%, w/w), polyvinylpyrrolidine (PVP, 2 or 3%, w/w), polycarbophil (PC, 1 or 3%, w/w) and tetracycline (5%, w/w, as the hydrochloride). Each formulation was characterised in terms of drug release, hardness, compressibility, adhesiveness (using a texture analyser in texture profile analysis mode), syringeability (using a texture analyser in compression mode) and adhesion to a mucin disc (measured as a detachment force using the texture analyser in tensile mode). The release exponent for the formulations ranged from 0.78+/-0.02 to 1. 27+/-0.07, indicating that drug release was non-diffusion controlled. Increasing the concentrations of each polymeric component significantly increased the time required for 10 and 30% release of the original mass of tetracycline, due to both increased viscosity and, additionally, the unique swelling properties of the formulations. Increasing concentrations of each polymeric component also increased the hardness, compressibility, adhesiveness, syringeability and mucoadhesion of the formulations. The effects on product hardness, compressibility and syringeability may be due to increased product viscosity and, hence, increased resistance to compression. Similarly, the effects of these polymers on adhesiveness/mucoadhesion highlight their mucoadhesive nature and, importantly, the effects of polymer state (particularly PC) on these properties. Thus, in formulations where the neutralisation of PC was maximally suppressed, adhesiveness and mucoadhesion were also maximal. Interestingly, statistical interactions were primarily observed between the effects of HEC and PC on drug release, mechanical and mucoadhesive properties. These were explained by the effects of HEC on the physical state of PC, namely swollen or unswollen. In the preliminary clinical evaluation, a formulation was selected that offered an appropriate balance of the above physical properties and contained 3% HEC, 3% PVP and 1% PC, in addition to tetracycline 5% (as the hydrochloride). The clinical efficacy of this (test) formulation was compared to an identical tetracycline-devoid (control) formulation in nine periodontal pockets (>/=5 mm depth). One week following administration of the test formulation, there was a significant improvement in periodontal health as identified by reduced numbers of sub-gingival microbial pathogens. Therefore, it can be concluded that, when used in combination with mechanical plaque removal, the tetracycline-containing semi-solid systems described in this study would augment such therapy by enhancing the removal of pathogens, thus improving periodontal health.

Examination of the physical state of chlorhexidine within viscoelastic, bioadhesive semisolids using raman spectroscopy

This study examined the effects of polymeric components on the physical state of chlorhexidine within bioadhesive, semisolid formulations using Raman spectroscopy. Semisolid formulations were prepared in which chlorhexidine base (CHX, 5%w/w, particle size <63 microm) was dispersed in aqueous (phosphate-buffered saline, pH 6.8) polymer matrices consisting of one or more polymeric components, namely HEC (3%w/w), PVP (3%), and PC (PC, 3%). Raman spectra were recorded using 785-nm excitation and were typically accumulated for 360 s. The Raman spectra were dominated by the presence of CHX. The spectra of CHX in HEC and in HEC/PVP gels were indistinguishable from that for solid CHX as a result of the insolubility of CHX in these formulations. However, in systems containing PC and CHX, there was a shift in the strongest band from 1564 cm(-1) to 1608 cm(-1), which may be accredited to protonation of the basic CHX by the numerous carboxylic acidic groups on PC. Identical shifts in the band positions were observed when this protonation was modeled using ethanoic acid, supporting the view that there was a simple acid base reaction between PC and CHX. However, there were notable differences in the relative intensities of the peaks from these samples, with the spectrum of CHX in the PC matrix displaying properties intermediate between those of CHX dissolved in ethanoic acid and solid CHX diacetate. This may be accredited to the limited solubility of the CHX-PC ion pair. In matrices containing HEC and PC, no peak was observed at 1564 cm(-1), whereas the intensity of the peak at 1608 cm(-1) was increased. Therefore, in these formulations CHX was completely converted to the di-cation as a result of the synergistic effects of PC (which protonated CHX) and HEC (which solubilized the di-cation). In the absence of either HEC or PC, complete protonation was not achieved. It is suggested that this enhancement of solubility of H(2)CHX(2+) may be due to hydrogen bonding, given the hydroxylated nature of HEC. In conclusion, this study has shown the applicability of Raman spectroscopy for both the analysis of opaque, semisolid formulations and, additionally, for the examination of the state of therapeutic agents within such matrices. In particular, using Raman spectroscopy, it was uniquely possible to identify the roles of various polymeric components on both the ionization and solubilization of CHX within aqueous semisolid systems.

MuStaR and other software for locus-specific mutation databases

As the human genome sequencing project nears completion, there has been a vast increase in the rate at which disease and nondisease associated variant sequences are being sought and detected. This has heightened the need for software with which to accumulate allelic variant (mutation) data, and with which to make the data accessible to the scientific community. Many ad hoc solutions have been developed by those interested in specific genes and diseases, and the creation of central databases which hold data for all genes has provided an alternative repository for some of the locus data. Despite this, few specialised software tools exist for researchers to create their own locus-specific allelic variant databases. This article describes methods available to potential curators, including software systems developed with the sole purpose of generating locus-specific mutation databases. In particular, the authors' own software, MuStaRtrade mark, is described. MuStaRtrade mark allows curators to maintain a database on a laptop computer if desired, while being able to export the data to an automatically generated Website which will run on any cgi compliant Web server. Searching the database and the submission of new mutations are made possible through fill-in Web forms. A number of other software tools which may be of use to curators are also described.

Ethnic differences in hormone replacement prescribing patterns

OBJECTIVE

To determine whether prescription patterns of hormone replacement therapy (HRT) differ in African-American, Asian, Latina, Soviet immigrant, and white women.

DESIGN

Retrospective review of computerized medical records.

SETTING

The general internal medicine, family medicine, and gynecology practices of an academic medical center.

PATIENTS

Women aged 50 years or older with at least one outpatient visit from January 1, 1992, to November 30, 1995.

MEASUREMENTS AND MAIN RESULTS

Use of HRT was defined as documentation of systemic estrogen use. The main predictor variable was self-identified ethnicity. Age, diagnosis (coronary heart disease, hypertension, diabetes, osteoporosis, or breast cancer), and median income were included in the analysis. Of the 8,968 women (mean age, 65.4 years) included, 50% were white, 20% Asian, 15% African American, 9% Latina, and 6% Soviet immigrants. Whites (33%) were significantly more likely to be prescribed HRT than Asians (21%), African Americans (25%), Latinas (23%), or Soviet immigrants (6.6%), p < 0.01 for each. Multivariate analysis, comparing ethnic groups and controlling for confounding variables, showed that Asians (odds ratio [OR] 0.56; 95% confidence interval [CI] 0.49, 0.64), African Americans (OR 0.70; 95% CI 0.60, 0.81), Latinas (OR 0.70; 95% CI 0.58, 0.84), and Soviet immigrants (OR 0.14; 95% CI 0.10, 0. 20) were each less likely to be prescribed HRT than were white women. Although women with osteoporosis were more likely to receive HRT (OR 2.28; 95% CI 1.71, 2.99), those with coronary heart disease were not (OR 0.88; 95% CI 0.68, 1.09).

CONCLUSIONS

Physicians at this medical center were more likely to prescribe HRT for white women and women with osteoporosis. Further study is needed to address whether these differences in HRT prescribing result in different health outcomes.

Hormone replacement therapy for African American women: missed opportunities for effective intervention

OBJECTIVES

Because of the potential benefits and risks of hormone replacement therapy (HRT), information about the efficacy of HRT in different groups of women is important to patients and providers. The objectives of this study were to review the evidence on the benefits and risks of HRT in African American women and to present a quantitative analysis of the potential reduction in mortality from osteoporotic fractures and coronary heart disease and the potential increase in risk of breast and endometrial cancer.

METHODS

A MEDLINE search of English-language observational studies and clinical trials on the effects of HRT on osteoporotic fractures and coronary heart disease (CHD) was conducted for the time period from 1966 to September 1998. Using available CHD mortality data for African American women and white women, potential reductions in mortality with HRT were explored for African American and white women.

RESULTS

In the 30 studies on CHD and HRT, African American women were known to comprise only 173 (0.1%) of 148,437 participants. In 11 studies of HRT and osteoporotic fractures, only 128 (0.4%) of 40,299 participants were known to be African American women. An analysis of CHD mortality by decade intervals indicated that African American women, aged 55 to 64, are more likely to die from CHD each year than white women. Despite a lower incidence of breast and endometrial cancer among African American women, the mortality rates of African American women with these cancers is higher compared with white women.

CONCLUSIONS

With the higher underlying CHD mortality rate among African American women, HRT is an important potential preventive therapy. The absence of African American women and other non-white women from clinical studies of HRT makes it difficult to fully assess the risks and benefits of HRT in this group of women.

Variation of glucosinolates in vegetable crops of Brassica oleracea

Glucosinolates were evaluated in 5 groups and 65 accessions of Brassica oleracea (50 broccoli, 4 Brussels sprouts, 6 cabbage, 3 cauliflower, and 2 kale) grown under uniform cultural conditions. Glucosinolates and their concentrations varied among the different groups and within each group. The predominant glucosinolates in broccoli were 4-methylsulfinylbutyl glucosinolate (glucoraphanin), 3-butenyl glucosinolate (gluconapin), and 3-indolylmethyl glucosinoate (glucobrassicin). Glucoraphanin concentration in broccoli ranged from 0.8 micromol g(-1) DW in EV6-1 to 21.7 micromol g(-1) DW in Brigadier. Concentrations of the other glucosinolates in broccoli varied similarly over a wide range. In Brussels sprouts, cabbage, cauliflower, and kale, the predominant glucosinolates were sinigrin (8.9, 7.8, 9.3, and 10.4 micromol g(-1) DW, respectively) and glucobrassicin (3.2, 0.9, 1.3, and 1.2 micromol g(-1) DW, respectively). Brussels sprouts also had significant amounts of gluconapin (6.9 micromol g(-1) DW). Wide variations in glucosinolate content among genotypes suggest differences in their health-promoting properties and the opportunity for enhancement of their levels through genetic manipulation.

Viscoelastic properties of bioadhesive, chlorhexidine-containing semi-solids for topical application to the oropharynx

PURPOSE

This study examined the viscoelastic properties of bioadhesive, chlorhexidine-containing semi-solid formulations, designed for topical application to the oropharynx.

METHODS

Oscillatory rheometry was performed using a Carri-Med CSL2-100 rheometer at 20.0 +/- 0.1 degrees C in conjunction with parallel plate geometry (2 cm diameter, 0.5 mm sample thickness). Samples were subjected to a constant strain (6.5 x 10(-3) rad) and defined viscoelastic parameters, namely storage modulus (G'), loss modulus (G"), loss tangent (tan delta) and dynamic viscosity (eta'), measured over a defined frequency range (0.01-1.0 Hz).

RESULTS

As the oscillatory frequency was increased, G' G" of all formulations increased, whereas both eta' and tan delta significantly decreased. The magnitude of increase of G' and G" as a function of frequency was relatively small, indicating that, in general, the formulations were non-cross-linked elastic systems. Increasing concentrations of HEC, PVP and PC significantly increased G', G", eta' yet decreased tan delta, observations that may be attributed to the physical state of each polymer in the formulations. Formulation elasticity increased (i.e. tan delta decreased) as a result of increased entanglement of polymeric chains of dissolved components (i.e. HEC and PVP) and the restrained extension of swollen, cross-linked chains of PC. Additionally, in formulations where the saturation solubility of PVP was exceeded and/or insufficient "free-water" was available for maximal swelling of PC, formulation elasticity increased as a result of the increasing mass of dispersed solid particles of PVP and/or PC. Formulation eta' increased due to the attendant effects of polymer chain entanglement and polymer state on overall formulation viscosity.

CONCLUSIONS

Following application to the oropharynx, the formulations will behave as elastic systems. Thus, these formulations would be expected to offer advantageous clinical properties, e.g., prolonged drug release, increased bioadhesion. However, it is noteworthy that the final choice of formulation for clinical evaluation will involve a compromise between viscoelastic characteristics and acceptable textural properties, e.g. ease of product application. This study has shown the applicability of oscillatory rheometry for both the characterisation and selection of candidate, topical bioadhesive formulations for clinical evaluation.

Tick bite anaphylaxis in Australia

Tick bite anaphylaxis has rarely been reported. It may follow the bite of any of the different tick life cycle forms, is related to the release of salivary juices, and may range from mild itch to severe wheeze or shock. Data obtained suggest that it is more common and potentially life threatening than tick paralysis, which is more widely reported. Emergency physicians should recognise this possibility following a tick bite and be prepared to give treatment such as adrenaline rapidly. Patients should be referred to an allergist after recovery.

Ciguatera poisoning: an example of a public health challenge

Ciguatera is a common form of fish poisoning, endemic in all nations of the Pacific region. Several thousand cases have been notified to Queensland authorities over a 10-year period. However, many cases remain undiagnosed and most go unreported. The public health implications include raising awareness of the condition, ensuring that ciguatera is considered in differential diagnosis and promoting better documentation and reporting.

Textural analysis and flow rheometry of novel, bioadhesive antimicrobial oral gels

PURPOSE

This study examined the rheological and textural characteristics (hardness, compressibilty, adhesiveness and cohesiveness) of bioadhesive oral gels containing the antimicrobial agent chlorhexidine.

METHODS

Textural analysis was performed using a Stable Micro Systems texture analyser (model TA-XT 2) in texture profile analysis (TPA) mode. In this, an analytical probe was twice compressed into each formulation to a defined depth (15 mm) and at defined rates (2, 4, 6, 8, 10 mm s-1), allowing a delay period (15 s) between the end of the first and beginning of the second compressions. Flow rheograms were performed using a Carri-Med CSL2-100 rheometer with parallel plate geometry under controlled shearing stresses at 20.0 +/- 0.1 degrees C.

RESULTS

All formulations exhibited pseudoplastic flow with thixotropy. Increasing concentrations of each polymer significantly increased formulation hardness, compressibility, adhesiveness and zero-rate viscosity. Increased hardness and compressibility were due to the attendent increased viscosities of these formulations. Increased adhesiveness was related to the concentrations of the (bioadhesive) polymers employed in these formulations and, in addition, was dependent on the physical state of polycarbophil. Formulation viscosity contributed to product adhesiveness, reflecting the importance of product rheology on this parameter. Decreased formulation cohesiveness, observed as the concentrations of the PVP, PC and HEC (3-5% w/w) were increased, was due an increase in semi-solid character. Numerical values of hardness, compressibility and adhesiveness were affected by the choice of probe speed, a parameter related to rate of shear in flow rheometry. Statistical interactions were observed and were assigned to the effects of HEC on the physical state of PVP (dissolved or dispersed) and PC (swollen or unswollen).

CONCLUSIONS

This study has demonstrated both the applicability of textural analysis for the mechanical characterisation of bioadhesive semi-solid gel systems and, additionally, the direct influence of viscosity on the parameters defined by textural analysis, namely, hardness, compressibility and adhesiveness.

Hospitalization for congestive heart failure. Explaining racial differences

OBJECTIVE

To determine whether the higher rate of hospitalization among African Americans for congestive heart failure (CHF) could be explained by racial differences in the prevalence of clinical risk factors for CHF.

DESIGN

Retrospective cohort study.

SETTING

A large health maintenance organization (HMO).

PATIENTS

A sample of 64,877 enrollees (27% African American and 73% white) of the Northern California Kaiser Permanente Medical Care Program who took at least one multiphasic health checkup (MHC) at or after the age of 40 years and were free of CHF at that time.

MAIN OUTCOME MEASURES

First hospitalization with a principal diagnosis of CHF.

RESULTS

Among cohort members younger than 60 years at baseline MHC, the age-adjusted risk ratio (RR) (African American/white) for CHF hospitalization was 2.14 for men and 2.73 for women, while for persons 60 years of age and older at MHC, the age-adjusted RR was 1.48 for both sexes. Cox proportional hazards models were used to adjust for risk factors and length of follow-up. In persons aged 60 years and older, the race difference was explained by greater prevalence of hypertension and diabetes in African Americans (RR = 1.12; 95% confidence interval [CI], 0.94 to 1.34 after adjustment for hypertension and diabetes). In those younger than 60 years, findings differed by sex. For men, African-American race was no longer a significant predictor of CHF after adjusting for hypertension, diabetes, left ventricular hypertrophy on electrocardiogram, and body mass index (adjusted RR = 1.16; 95% CI, 0.86 to 1.56). However, among younger women, African Americans continued at increased risk despite adjustment for these variables as well as smoking, plasma cholesterol, renal function, alcohol use, and myocardial infarction (adjusted RR = 1.49; 95% CI, 1.00 to 2.21).

CONCLUSIONS

In this HMO population, the race differences in first hospitalization for CHF are largely explained by known clinical and behavioral risk factors, although in younger women these risk factors do not completely explain the excess risk among African Americans. These findings highlight the role of hypertension and diabetes in the development of CHF, particularly among African Americans.

Automated linkage analysis in psychiatric disorders

A genome-wide search for linkage of microsatellite markers to chromosomal loci containing genes responsible for the major psychoses is a laborious task which can be carried out with greater speed and economy by introducing automation to several steps in the procedure. We describe the use of the Automated Linkage Preprocessor (ALP) program for the computer analysis of the waveform generated by fluorescein-labelled markers after electrophoretic separation. (To obtain a copy send a request to A.F. Brown at the below MRC address or use Anonymous FTP to ftp.hgu.mrc.ac.uk. Software is in directory pub/ALP). The program runs on a PC in the Microsoft Windows environment, and is used in conjunction with an automated laser fluorescence (ALF) sequencer (Pharmacia) and its Fragment Manager software to detect and size the PCR products, filter out peaks of fluorescence due to nonallele fragments, and generate genotypes in a format suitable for direct input to standard linkage analysis programs. The method should offer the advantages of speed, accuracy, and reduced cost. Its use in linkage studies in a large family with manic-depressive illness is discussed.

Chainsaw penetrating neck injury

A case of chainsaw injury to the neck is described. Previous reports in the English language are exceedingly rare. A brief discussion of safety features on chain saws is followed by a review of selective vs. mandatory surgical exploration in penetrating neck trauma, including the role of ancillary diagnostic tests.

Anaphylactic shock: mechanisms and treatment

This paper reviews the mechanisms of anaphylactic shock in terms of the immunoglobulin and non-immunoglobulin triggering events, and the cellular events based on the rise in intracellular cyclic AMP and calcium that release preformed granule-associated mediators and the rapidly formed, newly synthesized mediators predominantly based on arachidonic acid metabolism. These primary mediators recruit other cells with the release of secondary mediators that either potentiate or ultimately curtail the anaphylactic reaction. The roles of these mediators in the various causes of cardiovascular collapse are examined. The treatment of anaphylactic shock involves oxygen, adrenaline and fluids. The importance and safety of intravenous adrenaline are discussed. Combined H1 and H2 blocking antihistamines and steroids have a limited role. Glucagon and other adrenergic drugs are occasionally used, and several new experimental drugs are being developed.

Automation of genetic linkage analysis using fluorescent microsatellite markers

Automation of the typing of genetic markers offers advantages of speed, accuracy, and cost in the mapping of genetic traits and the construction of high-resolution linkage maps. We have developed an automated linkage analysis system by (i) using a robotic pipettor to set up polymerase chain reactions (PCR) to amplify microsatellites with incorporation of a single fluorescent label; (ii) using an automated sequencing apparatus for detection of the PCR products; (iii) sizing alleles automatically by the use of internal and external standards; (iv) iteratively filtering out nonallelic fragments and checking for Mendelian consistency; (v) calculating the probabilities of selected genotypes; and (vi) automatically formatting the results for input to linkage analysis programs. The method provides accurate sizing of alleles, minimizes the risk of error during manual reading and transcription of data, and increases the throughput of reliable data. It brings any inconsistencies or ambiguities in the data to the attention of the user and facilitates examination of the raw data. The ALF/ALP system, together with new, optimized microsatellite sets, particularly tetranucleotide repeats, is likely to be well-suited to fully automatic genetic linkage analysis.

The Flexipore 6000 membrane as a wound dressing for use in the accident and emergency department

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