Accuracy of Dental Implant Placement using Robotics. A Systematic Review of in vitro Studies

PURPOSE/AIM

Robotic-assisted techniques have the potential to revolutionize dental implantology by offering enhanced precision, accuracy, and clinical outcomes compared to computer-assisted implant placement techniques. This study aimed to evaluate the accuracy of dental implant placement using robot-assisted implant surgery in vitro settings.

METHODS

An unrestricted search of indexed databases along with a manual search was performed up to March 2024. In vitro, studies comparing the positioning accuracy of robotic systems in dental implant placement of planned pre-operative coordinates and postoperative outcomes in phantom and simulated models were included. QUIN Tool was used to assess the quality of the included studies.

RESULT

A total of 13 in vitro studies were included. All studies except one used entry, exit, or angle deviation as parameters to assess the accuracy of implants placed on phantom models or simulated virtual implant placement. Overall, pooled entry deviations were 0.72 ± 0.68 mm, exit deviations were 0.86 ± 0.92 mm, and angular deviations were 1.47 ± 1.610 favoring robot-assisted implant surgery.

CONCLUSION

Based on the current evidence, robotic-placed implants have the potential to revolutionize dental implantology by offering enhanced precision, accuracy, and clinical outcomes compared to dynamic and static computer-assisted implant surgery techniques.

LipidSIM: Inferring mechanistic lipid biosynthesis perturbations from lipidomics with a flexible, low-parameter, Markov modeling framework

Lipid metabolism is a complex and dynamic system involving numerous enzymes at the junction of multiple metabolic pathways. Disruption of these pathways leads to systematic dyslipidemia, a hallmark of many pathological developments, such as nonalcoholic steatohepatitis and diabetes. Recent advances in computational tools can provide insights into the dysregulation of lipid biosynthesis, but limitations remain due to the complexity of lipidomic data, limited knowledge of interactions among involved enzymes, and technical challenges in standardizing across different lipid types. Here, we present a low-parameter, biologically interpretable framework named Lipid Synthesis Investigative Markov model (LipidSIM), which models and predicts the source of perturbations in lipid biosynthesis from lipidomic data. LipidSIM achieves this by accounting for the interdependency between the lipid species via the lipid biosynthesis network and generates testable hypotheses regarding changes in lipid biosynthetic reactions. This feature allows the integration of lipidomics with other omics types, such as transcriptomics, to elucidate the direct driving mechanisms of altered lipidomes due to treatments or disease progression. To demonstrate the value of LipidSIM, we first applied it to hepatic lipidomics following Keap1 knockdown and found that changes in mRNA expression of the lipid pathways were consistent with the LipidSIM-predicted fluxes. Second, we used it to study lipidomic changes following intraperitoneal injection of CCl4 to induce fast NAFLD/NASH development and the progression of fibrosis and hepatic cancer. Finally, to show the power of LipidSIM for classifying samples with dyslipidemia, we used a Dgat2-knockdown study dataset. Thus, we show that as it demands no a priori knowledge of enzyme kinetics, LipidSIM is a valuable and intuitive framework for extracting biological insights from complex lipidomic data.

Factors contributing to the nonlinear pharmacokinetics of astegolimab: a close examination of potential causes

Aim: This paper describes a case study of an antibody therapeutic targeting a membrane-bound receptor, also present in systemic circulation, as a soluble receptor. During phase I studies of astegolimab, nonlinear pharmacokinetics (PKs) were observed. We investigated the potential contribution of antidrug antibodies, target-mediated drug disposition and assay format. Materials & methods: A more target-tolerant assay was developed, and a subset of phase I samples were evaluated in both free and total PK assay formats. Results & conclusion: Our results demonstrate that there were two main contributors to PK nonlinearity: soluble target interference in the free PK assay, in addition to target-mediated drug disposition. Antidrug antibody status did not significantly impact PK.

Managing an adult CF population in the COVID-19 pandemic-1 year on

BACKGROUND

The advent of the COVID-19 pandemic in 2020 required an alteration in the routine care of people with CF (pwCF), deemed to be extremely vulnerable.

AIM

We wished to report the alterations in clinical practice, including the introduction of remote video-assisted clinics, made to manage the adult pwCF attending our large centre.

METHODS

We studied clinical records over a period of 2 years (March 2019 to February 2021) by comparing 19th March to 20th February (Y1) with 20th March to 21st February (Y2).

RESULTS

We have shown out of hospital Multi Disciplinary Team (MDT) support increased and a greater proportion of IV therapy was administered at home. The VAC model of care increased clinical activity while reducing clinic non-attendance rates, suggesting more individuals engage with their carers.

CONCLUSIONS

This new model of care has allowed greater engagement with pwCF.

Did it hurt? COVID-19 vaccination experience in people with multiple sclerosis

Background

Current guidelines recommend vaccination against SARS-CoV2 for people with multiple sclerosis (pwMS). The long-term review of the safety and effectiveness of COVID-19 vaccines in pwMS is limited.

Methods

Service re-evaluation. PwMS using the MS service at Barts Health National Health Service Trust were sent questionnaires via email to report symptoms following first and second COVID-19 vaccinations (n = 570). A retrospective review of electronic health records was conducted for clinical and safety data post-vaccination(s); cut-off was end of September 2021. Separate logistic regressions were carried out for symptoms experienced at each vaccination. Two sets of regressions were fitted with covariates: (i) Disease-modifying therapy type and (ii) patient characteristics for symptoms experienced.

Results

193/570 pwMS responded. 184 pwMS had both vaccinations. 144 received the AZD1222 and 49 the BNT162b2 vaccine. 87% and 75% of pwMS experienced any symptoms at first and second vaccinations, respectively. The majority of symptoms resolved within a short timeframe. No severe adverse effects were reported. Two pwMS subsequently died; one due to COVID-19 and one due to aspiration pneumonia. Males were at a reduced risk of reporting symptoms at first vaccination. There was evidence that pwMS in certain treatment groups were at reduced risk of reporting symptoms at second vaccination only.

Conclusions

Findings are consistent with our preliminary data. Symptoms post-vaccination were similar to the non-MS population and were mostly temporary. It is important to inform the MS community of vaccine safety data.

PrP concentration in the central nervous system: regional variability, genotypic effects, and pharmacodynamic impact

Prion protein (PrP) concentration controls the kinetics of prion replication and is a genetically and pharmacologically validated therapeutic target for prion disease. In order to evaluate PrP concentration as a pharmacodynamic biomarker and assess its contribution to known prion disease risk factors, we developed and validated a plate-based immunoassay reactive for PrP across six species of interest and applicable to brain and cerebrospinal fluid (CSF). PrP concentration varies dramatically between different brain regions in mice, cynomolgus macaques, and humans. PrP expression does not appear to contribute to the known risk factors of age, sex, or common PRNP genetic variants. CSF PrP is lowered in the presence of rare pathogenic PRNP variants, with heterozygous carriers of P102L displaying 55% and of D178N just 31% the CSF PrP concentration of mutation-negative controls. In rodents, pharmacologic reduction of brain Prnp RNA is reflected in brain parenchyma PrP, and in turn in CSF PrP, validating CSF as a sampling compartment for the effect of PrP-lowering therapy. Our findings support the use of CSF PrP as a pharmacodynamic biomarker for PrP-lowering drugs, and suggest that relative reduction from individual baseline CSF PrP concentration may be an appropriate marker for target engagement.

Best practices for the development and fit-for-purpose validation of biomarker methods: a conference report

This conference report summarized a full-day workshop, “best practices for the development and fit-for-purpose validation of biomarker methods,” which was held prior to the American Association of Pharmaceutical Scientists (AAPS) PharmSci360 Congress, San Antonio, TX, November 2019. The purpose of the workshop was to bring together thought leaders in biomarker assay development in order to identify which assay parameters and key statistical measures need to be considered when developing a biomarker assay. A diverse group of more than 40 scientists participated in the workshop. The workshop and subsequent working dinner stimulated robust discussion. While a consensus on best practices was not achieved, some common themes and major points to consider for biomarker assay development have been identified and agreed on. The focus of this conference report is to summarize the presentations and discussions which occurred at the workshop. Biomarker assay validation is a complex and an evolving area with discussions ongoing.

Experience with the COVID-19 AstraZeneca vaccination in people with multiple sclerosis

Background

Some people with multiple sclerosis (pwMS) are at increased risk of severe Coronavirus disease 19 (COVID-19) and should be rapidly vaccinated. However, vaccine supplies are limited, and there are concerns about side-effects, particularly with the ChAdOx1nCoV-19 (AstraZeneca) vaccine.

Objectives

To report our first experience of pwMS receiving the AstraZeneca vaccine.

Methods

Service evaluation. pwMS using the MS service at Barts Health NHS Trust were sent questionnaires to report symptoms following vaccination.

Results

Thirty-three responses were returned, 29/33 pwMS received a first dose of AstraZeneca vaccine, the remaining four received a first dose of BioNTech/Pfizer vaccine.

All but two patients (94%) reported any symptoms including a sore arm (70%), flu-like symptoms (64%), fever (21%), fatigue (27%), and headache (21%). In more than 2/3 patients, symptoms lasted up to 48 hours, and with the exception of two pwMS reporting symptom duration of 10 and 12 days, respectively, symptoms in the remainder resolved within seven days. No severe adverse effects occurred.

Conclusions

pwMS report transient symptoms following AstraZeneca vaccination, characteristics of which were similar to those reported in the non-MS population. Symptoms may be more pronounced in pwMS due to the temperature-dependent delay in impulse propagation (Uhthoff's phenomenon) due to demyelination.

Severe skin reactions associated with cladribine in people with multiple sclerosis

OBJECTIVE

To report three cases of severe skin reactions in patients treated with cladribine for multiple sclerosis.

METHODS

Case study.

RESULTS

Patients developed severe rash 3-192 days after receiving cladribine. All were effectively treated with steroids and antihistamines. Additional doses of cladribine were administered after pretreatment with steroids and anti-histamines. One patient developed mild recurrence following re-exposure, which resolved within three days, whilst another patient tolerated re-exposure without further adverse reaction.

CONCLUSION

Severe skin reactions, well described in patients receiving cladribine for treatment of haematological conditions, may occur in patients treated with this compound for multiple sclerosis. Neurologists need to be aware of this rare, but significant adverse reaction. Re-exposure may be safe with standard pre-treatment against allergic reactions.

Abstract P1-13-08: A prospective non-randomized clinical trial of adjuvant carboplatin chemotherapy in triple negative breast cancer

Background: The addition of carboplatin in the neoadjuvant setting has demonstrated improved outcomes in patients with triple negative breast cancer (TNBC). Carboplatin in the adjuvant setting has not been demonstrated to be an accepted regimen to date. This trial addresses this issue.

Methods: The primary objectives of this study were to assess the toxicity of an adjuvant carboplatin-containing regimen for early stage TNBC patients, and to correlate outcomes with molecular markers including Spy-1. Secondary objectives included determination of progression free (PFS) and overall survival (OS), and comparing these to our institutional historical controls. Patients received the backbone of a dose dense anthracycline, taxane, cyclophosphamide (DD ACT), with the addition of carboplatin.

Results: Ninety patients with stage I to III patients with triple negative breast cancer were accrued to this trial between Jan 2011 and June 2017. We discovered that DD ACT with carboplatin with an AUC of 5 given on the second and last paclitaxel was well tolerated. Chemotherapy delays were minimized when the parameters for administration of the carboplatin was to allow chemotherapy to proceed if the platelet count was >/= 70,000 x10^9/L and dose adjustment of paclitaxel was allowed based on neuropathy. There were no grade 4 adverse events. 4% of patients had grade 3 peripheral neuropathy (PN), 28% had grade 2 PN and 45% had grade 1 PN. Results of molecular profiles will be reported. Univariate analysis are reported, and were found to be very promising. Using log-rank statistic, a trend to improvement in overall survival was found when compared to historical controls (p=0.089). Median follow-up is 24 months. Longer follow-up is necessary to determine PFS and overall survival benefit.

Conclusion: If considering an adjuvant regimen for triple negative breast cancer patients DDAC/TC with the carboplatin administered with an AUC of 5 on the second and fourth taxol of DDACT is a well-tolerated regimen.

Univariate Analysis Comparing Carboplatin vs Historical Controls that did not receive CarboplatinVariableHistorical (no carbo)Carbo containing chemop overall n = 179n = 82 Age56.3 (13.1)49.8 (11.0)< 0.001Stage0.188Stage I47 (26.3%)15 (18.3%) Stage II88 (49.2%)50 (61.0%) Stage III44 (24.6%)17 (20.7%) Grade0.011Grade 18 (4.5%)0 (0.0%) Grade 233 (18.4%)7 (8.8%) Grade 3138 (77.1%)73 (91.2%) Remission Status0.009In Remission126 (70.4%)70 (86.4%) Relapsed53 (29.6%)11 (13.6%) Survival< 0.001Alive121 (67.6%)73 (90.1%) Deceased58 (32.4%)8 (9.9%) 

Citation Format: Hamm C, Kulkarni S, Gupta R, Mathews J, Amin K, Hussein A, Porter L. A prospective non-randomized clinical trial of adjuvant carboplatin chemotherapy in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-13-08.

Bacterial endotoxins and microorganisms in the oral cavities of patients on cancer therapy

OBJECTIVES

This study investigated the presence of Streptococci, Staphylococci, aerobic gram negative bacteria (AGNB), Candida and bacterial endotoxins in the oral cavities of patients receiving chemo- and/or radiotherapy for cancer.

METHODS

Samples of oral cavity rinse were collected from 100 patients on cancer treatment and 70 healthy individuals. Demographic and clinical data were recorded. Samples were cultured onto various agar plates for qualitative and quantitative analysis and tested for the presence of endotoxin. Results were analysed using the Mann-Whitney and chi-square tests.

RESULTS

In cancer patients, S. aureus counts were high and 66.7% of patients on chemo- and radiotherapy carried these bacteria (p=<0.05). The Candida carrier rate was significantly (p < 0.01) high in cancer patients (54%). No significant difference was found in the carrier rate of Streptococci and AGNB between the healthy and cancer group as well as between the cancer patients with chemo and radio- and chemotherapy alone. No significant difference was found in the level of endotoxin between the cancer patients and healthy individuals, and cancer patients with and without AGNB.

CONCLUSIONS

No differences in the prevalence of bacteria and bacterial endotoxins were found between the cancer patients and healthy individuals. Oral cavity endotoxins did not correlate with the carriage of AGNB. However, due to the high prevalence in cancer patients, the role of Candida species and S. aureus in the pathology may not be excluded.

Prevalence of Deleterious Oral Habits and Oral Mucosal Lesions among Fishermen Population of Mahe, South India

INTRODUCTION

Fishing is an occupation associated with uneven diet, strain, drunkenness, tobacco use, and deleterious habits. The physical state of laborers on a large scale will also be influenced by conditions at their work site. Oral mucosal lesions can occur as a result of infections, local shock or infuriation, systemic diseases, and uncontrolled usage of tobacco, betel quid, and alcohol. The aim of the present study is to assess the prevalence of deleterious oral habits and oral mucosal lesions among fishermen population of Mahe, South India.

MATERIALS AND METHODS

The study population consists of 362 fishermen aged between 15 and 54. The questionnaire consisted of questions on personal data, and information related to the subjects' oral habits were collected by the interview. The World Health Organization (WHO) Oral Health Assessment Form was designed for the assessment of oral mucosal lesions.

RESULTS

Among the 362 fishermen, 266 (73.48%) were males and 96 (26.52%) were females. The overall prevalence of smoking, alcohol consumption, and gutka chewing was found to be 24.3, 48.85, and 32.4% respectively. Smokeless tobacco (32.4%) was the most prevalent habit followed by smoking tobacco (24.3%). The prevalence of oral mucosal lesions was 14.9%. There is a statistically significant association between age groups and habits considered.

CONCLUSION

Findings of the present study suggest that oral health condition of the fisherfolk community was relatively poor, with high habit prevalence and oral mucosal lesions. This epi-demiological study has provided baseline data to plan further research in this area.

CLINICAL SIGNIFICANCE

Low socioeconomic status, strenuous working hours, inadequate diet and nutrition intake, stress, and use of tobacco and alcohol act as contributing factors for ill health and oral diseases. It is a challenging population to the clinician to identify and treat them.

ILC2 contribute to ozone-induced airway hyperresponsiveness in obese mice (HYP6P.266)

Many obese asthmatics have non atopic asthma, but the mechanistic basis is poorly understood. Ozone (O3), a common air pollutant, is an asthma trigger that causes airway hyperresponsiveness (AHR) and neutrophilic inflammation. O3-induced AHR and neutrophilia are augmented in obese vs lean mice. Innate lymphoid cells type 2 (ILC2) may be driving these responses. To address this hypothesis, lean WT and obese db/db mice were exposed to room air or O3 (2 ppm) for 3 h. 24 h later, we measured AHR and performed bronchoalveolar lavage (BAL). BAL IL-5, IL-13 and IL-33 were increased by O3 in obese but not lean mice. IL-5 and IL-13 can drive AHR and are secreted by ILC2. IL-33 signaling through ST2 drives activation of ILC2. Therefore, we pretreated db/db mice with ST2 blocking antibody (provided by Dirk Smith, Amgen) prior to O3 exposure. Blocking ST2 decreased O3-induced AHR, baseline lung mechanics, neutrophilia and BAL IL-5 in db/db mice. Anti-IL-13 also decreases BAL neutrophils and lung mechanics in obese mice after O3. IL-23, IL-7, IL-22, and IL-17A were also increased by O3 in obese mice, suggesting the possible involvement of ILC3, a cell activated by IL-7 and IL-23 that secretes IL-17A and IL-22. Blocking IL-17A in a separate cohort also decreased O3 induced AHR and neutrophilia in obese mice. Taken together, our data indicate that obese mice exposed to O3 have increased activation of ILC2 and ILC3 and that these cells are driving the asthma phenotype in these mice.

Oxidative stress-induced pulmonary neutrophil recruitment is independent of conventional dendritic cells (INC5P.325)

Oxidative stress and airway neutrophilia are key features of some asthma phenotypes. Ozone (O3), a potent oxidant, induces pulmonary neutrophil recruitment which requires IL-17A+ γδ T cells. IL-23 is required for IL-17A production by T cells and conventional dendritic cells (cDC) are a potent source of IL-23. We therefore hypothesized that oxidative stress-induced IL-17A+ γδ T cells require IL-23 production from cDC. Wild type (WT), Tcrd-/- (lacking γδ T cells), and flt3l-/- (deficient in cDC) mice were exposed to air or 0.3 ppm O3 for 72 h. Bronchoalveolar lavage (BAL) was collected for cell differentials and lungs were processed for qPCR analysis. Lungs from mice which were not lavaged were used for flow cytometric analysis. In WT mice, O3 caused a 4 fold increase in the percentage of lung CD11c+/MHCII+/Siglec-F+ dendritic cells. IL-23 mRNA was also increased after O3 exposure. Flt3l-/- and WT mice had similar amounts of IL-23 and IL-17A mRNA and BAL neutrophils, thus indicating that cDC are not the source of IL-23 after such oxidative stress. However, IL-23 mRNA was reduced in Tcrd-/- mice which had fewer CD11c-/ CD11b+/F4/80+ myeloid cells. These cells are thus the potential source of IL-23. Altogether these data suggest oxidative stress induces IL-23 production by non-dendritic myeloid cells leading to IL-17A+ γδ T cell driven neutrophil recruitment.

Sphenoid mucocele: an uncommon complication of a rare condition

A 58-year-old white woman presented with sudden onset of diplopia, headache and vomiting with a history of tiredness and lethargy over the past four to six months. She had smooth, pale, hairless skin and on examination she was found to have left-sided third and sixth nerve palsy. Laboratory tests confirmed pan-anterior hypopituitarism. Computerized tomography scan of head and magnetic resonance imaging appearances were consistent with those of a sphenoid sinus mucocoele. Following adequate replacement with hydrocortisone and thyroxine she underwent sphenoid mucocoele drainage and endoscopic left sphenoethmoidectomy. Her symptoms were relieved over the next few days and she had a near-total recovery of ophthalmoplegia over the following three months. Pituitary function tests showed partial resolution of hypopituitarism with recovery of hypothalamic-pituitary-adrenal axis and hydrocortisone therapy was withdrawn, but she continued to require thyroxine.

γ/δ T cells contribute to inflammation following long term low dose O3 exposure. (120.32)

γ/δ T cells are involved in the responses to acute high dose ozone (O3) exposure (2 ppm for 3 hrs)( Matsubara, S et al, AJRCMB, 2009). However, elevated atmospheric O3 tends to persist not for hours, but for several days. The factors that determine pulmonary responses to short-duration, high-dose O3 exposure are different from those involved in responses to longer, lower-dose exposures and it is not know what role γ/δ T cells have in these longer term exposures. Consequently, we exposed mice deficient in γ/δ T cells (TCRδ-/-) and WT mice to O3 (0.3 ppm for 48 hrs). Bronchoalveolar lavage (BAL) was performed and the lungs were collected, digested, and analyzed by FACS. O3 caused an increase in numbers of γ/δ T cells, macrophages, and neutrophils in the lung tissue and/or BAL fluid. BAL and lung tissue neutrophils and macrophages were reduced in TCRδ-/- versus WT mice. BAL fluid IP-10, IL-6, MCP-1, LIF and KC were lower in TCRδ-/- versus WT mice. These chemokines are chemoattractive for macrophages and/or neutrophils and most can be produced by lung γ/δ T cells. In contrast, we found no difference in O3 induced lung damage between the WT and TCRδ-/- mice, as assessed by BAL protein or scores of terminal bronchiolar lesions on histological sections. Our data indicate that γ/δ T cells are involved in the initiation of inflammation following O3 exposure, potentially through the secretion of chemokines that recruit macrophages and neutrophils.

A single-centre chart review exploring the adjusted association between breast cancer phenotype and prognosis

PURPOSE AND METHODS

Using a retrospective chart review, we investigated the differences in survival and prognostic factors between patients with triple-negative breast cancer (tnbc) and those with non-tnbc. The review included 1018 breast cancer patients who were diagnosed between 2000 and 2005 in Essex, Kent, and Lambton counties in Ontario, Canada.

RESULTS

Our findings indicate that, although the unadjusted results suggested that patients with tnbc were more likely than patients with non-tnbc to die [hazard ratio (hr): 2.29; 95% confidence interval (ci): 1.33 to 2.93], an adjusted survival analysis revealed no significant difference in overall survival between the groups (hr: 1.22; 95% ci: 0.63 to 2.39). The significant predictors of survival in the adjusted analysis were age, stage of cancer, and size of cancer.

CONCLUSIONS

Our findings support those of earlier reports, which suggest that presenting tumour size is the most important prognostic factor in tnbc. Investigations into unique screening methods to identify these tumours at an earlier stage and to prevent advanced-stage cancer in this patient subpopulation are necessary.

The emergence of ADAM10 as a regulator of lymphocyte development and autoimmunity

Proteolytic processing of transmembrane receptors and ligands can have a dramatic impact on cell signaling processes and subsequent cellular responses, including activation and differentiation. A member of the disintegrin and metalloproteinase family, ADAM10, has emerged as a prominent regulator of numerous receptors and ligands, including Notch and CD23. Here, we review studies resulting from the recent generation of ADAM10 conditional knockout mice which revealed a critical role for ADAM10 in Notch-dependent lymphocyte development. Additionally, we discuss results of numerous in vitro and ex vivo studies indicating that ADAM10 regulates the production of multiple secreted factors that contribute to autoimmune reactions.

Glutamate signaling through the kainate receptor enhances human immunoglobulin production

CD23 is implicated as a regulator of IgE synthesis. A soluble form of CD23 (sCD23) is released following cleavage by ADAM10 and enhanced sCD23 is correlated with increased IgE. In the CNS, signaling through the kainate receptor (KAR) increases ADAM10. In B cells, activation of KARs produced a significant increase in ADAM10 and sCD23 release as well as an increase in B cell proliferation and immunoglobulin production. In addition, ADAM10 inhibitors reduce IgE synthesis from in vitro cultures of human B cells. Thus, we report for the first time the unique presence of the kainate receptor in B cells and that activation of KARs could serve as a novel mechanism for enhancing B cell activation.

Acute cardiovascular effects of apelin in humans: potential role in patients with chronic heart failure

BACKGROUND

Apelin, the endogenous ligand for the novel G protein-coupled receptor APJ, has major cardiovascular effects in preclinical models. The study objectives were to establish the effects of acute apelin administration on peripheral, cardiac, and systemic hemodynamic variables in healthy volunteers and patients with heart failure.

METHODS AND RESULTS

Eighteen patients with New York Heart Association class II to III chronic heart failure, 6 patients undergoing diagnostic coronary angiography, and 26 healthy volunteers participated in a series of randomized, double-blind, placebo-controlled studies. Measurements of forearm blood flow, coronary blood flow, left ventricular pressure, and cardiac output were made by venous occlusion plethysmography, Doppler flow wire and quantitative coronary angiography, pressure wire, and thoracic bioimpedance, respectively. Intrabrachial infusions of (Pyr(1))apelin-13, acetylcholine, and sodium nitroprusside caused forearm vasodilatation in patients and control subjects (all P<0.0001). Vasodilatation to acetylcholine (P=0.01) but not apelin (P=0.3) or sodium nitroprusside (P=0.9) was attenuated in patients with heart failure. Intracoronary bolus of apelin-36 increased coronary blood flow and the maximum rate of rise in left ventricular pressure and reduced peak and end-diastolic left ventricular pressures (all P<0.05). Systemic infusions of (Pyr(1))apelin-13 (30 to 300 nmol/min) increased cardiac index and lowered mean arterial pressure and peripheral vascular resistance in patients and healthy control subjects (all P<0.01) but increased heart rate only in control subjects (P<0.01).

CONCLUSIONS

Acute apelin administration in humans causes peripheral and coronary vasodilatation and increases cardiac output. APJ agonism represents a novel potential therapeutic target for patients with heart failure.

Management of post-infectious olfactory dysfunction: a nationwide survey of UK ENT consultants

OBJECTIVE

To determine the current practice of UK ENT consultants in investigating cases of suspected post-infectious olfactory dysfunction.

METHOD

We prepared questionnaires and posted these to every consultant ENT surgeon registered with the British Association of Otolaryngologists Head and Neck Surgeons (BAO-HNS). Questions included preferred radiological investigation, smelling test and follow up.

RESULTS

A total of 510 questionnaires were sent, with a response rate of 51%. Most UK consultant ENT surgeons investigated suspected post-infectious olfactory dysfunction by performing either a CT (44%) or an MRI (29%) scan, but only 37% performed formal smell tests. Most consultant ENT surgeons (76%) decide not to follow up post-infectious olfactory dysfunction.

CONCLUSION

This study gives an indication that suspected post-infectious olfactory dysfunction is not investigated thoroughly in the United Kingdom, with only a minority of clinicians performing formal smell tests and a lack of consensus as to radiological investigation. Standardisation of investigations is key to adequately managing suspected post-infectious olfactory dysfunction.

Impacts of Hurricanes Katrina and Rita on the microbial landscape of the New Orleans area

Floodwaters in New Orleans from Hurricanes Katrina and Rita were observed to contain high levels of fecal indicator bacteria and microbial pathogens, generating concern about long-term impacts of these floodwaters on the sediment and water quality of the New Orleans area and Lake Pontchartrain. We show here that fecal indicator microbe concentrations in offshore waters from Lake Pontchartrain returned to prehurricane concentrations within 2 months of the flooding induced by these hurricanes. Vibrio and Legionella species within the lake were more abundant in samples collected shortly after the floodwaters had receded compared with samples taken within the subsequent 3 months; no evidence of a long-term hurricane-induced algal bloom was observed. Giardia and Cryptosporidium were detected in canal waters. Elevated levels of fecal indicator bacteria observed in sediment could not be solely attributed to impacts from floodwaters, as both flooded and nonflooded areas exhibited elevated levels of fecal indicator bacteria. Evidence from measurements of Bifidobacterium and bacterial diversity analysis suggest that the fecal indicator bacteria observed in the sediment were from human fecal sources. Epidemiologic studies are highly recommended to evaluate the human health effects of the sediments deposited by the floodwaters.

Aspirated stoma button: an unusual complication

The larynx functions as a protective valve of the upper airway. An end-tracheostomy represents a risk factor for foreign body aspiration. We describe a case of tracheostomy stoma button aspiration, leading to recurrent chest infection and irreversible lung damage, necessitating a pneumonectomy. This is the first reported case of this kind. This case also emphasizes the importance of patient education and of stoma button design.

Reflective consideration of postoperative endophthalmitis as a quality marker

PURPOSE

To study the incidence of acute postoperative presumed infectious endophthalmitis (PIE) in a UK district general hospital over a 10-year period. Consideration of such departmental healthcare-associated infection frequency rates as part of reflective and comparative quality practice in the light of local concerns.

METHODS

Hospital-based retrospective case series: 12 831 cataract extraction operations from 01/01/1995 to 31/12/2004 were studied. All cases of PIE within 6 weeks of cataract surgery were ascertained and investigated in a standardised format. PIE incidence rate per 1000 cataract surgical procedures was contrasted with the existing literature.

RESULTS

Seven isolated PIE cases occurred following phacoemulsification. None followed extra-capsular extractions. The PIE rate was 0.55 [95% CI; 0.22 to 1.12] cases per 1000 cataract extractions, or one PIE case within 6 weeks of surgery in every 1833 [95% CI; 893 to 4545] cataract operations undertaken. Five cases were culture positive. Details of PIE cases are presented.

CONCLUSION

PIE incidence rates in our department are slightly lower than reported case series in similar settings. Whether this is due to a variety of preventive measures deployed locally and/or methods of case ascertainment in published studies is problematic and is discussed. Departmental benchmarking data is important in relation to rare, but critical, patient safety incidents. Collection and monitoring of endophthalmitis outcomes is of merit and may inform patient choice. Surgical site infection surveillance systems of relevance are discussed. Implications for making healthcare safer, including reflective practice are, discussed in relation to cataract care.

Regulation of cellular infiltration into tissue engineering scaffolds composed of submicron diameter fibrils produced by electrospinning

We characterize the infiltration of interstitial cells into tissue engineering scaffolds prepared with electrospun collagen, electrospun gelatin, electrospun poly(glycolic) acid (PGA), electrospun poly(lactic) acid (PLA), and an electrospun PGA/PLA co-polymer. Electrospinning conditions were optimized to produce non-woven tissue engineering scaffolds composed of individual fibrils less than 1000 nm in diameter. Each of these materials was then electrospun into a cylindrical construct with a 2 mm inside diameter with a wall thickness of 200-250 microm. Electrospun scaffolds of collagen were rapidly, and densely, infiltrated by interstitial and endothelial cells when implanted into the interstitial space of the rat vastus lateralis muscle. Functional blood vessels were evident within 7 days. In contrast, implants composed of electrospun gelatin or the bio-resorbable synthetic polymers were not infiltrated to any great extent and induced fibrosis. Our data suggests that topographical features, unique to the electrospun collagen fibril, promote cell migration and capillary formation.

Closed versus partially ventilated endotracheal suction in extremely preterm neonates: physiologic consequences

This randomized cross over study aimed to compare the severity and incidences of desaturation and bradycardia between the partially ventilated endotracheal suction method (PVETS) and closed tracheal suction system (CTSS) in extremely preterm neonates. Fifteen intubated and ventilated extremely low birth weight preterm infants (mean birth weight 689g) randomly underwent both suction techniques within a 12-h period to obtain a paired reading group. The process was repeated 24-48h apart until three pairs of reading groups were collected. Changes in oxygen saturation measured with pulse oximetry and heart rate changes measured with electrocardiogram were recorded using Hewlett-Packard m240A monitor trending software. The mean of each parameter's variation from baseline was obtained using SPSS descriptive statistics and analyzed using SPSS repeated measures ANOVA. Fisher Exact Test was used to analyze the incidence of desaturation and bradycardia. The closed tracheal suction system reported a significantly smaller degree of oxygen saturation fall (P<0.005) and significantly fewer incidences of desaturation. There was also a significantly smaller degree of heart rate reduction although episodes of bradycardia were not significantly different between the two methods. Oxygen saturation and heart rate were significantly more stable during the use of CTSS compared to PVETS in the extremely low birth weight preterm population.