Antibody-Drug Conjugates in Triple Negative Breast Cancer

Triple negative breast cancer (TNBC) accounts for 15%-20% of all breast cancer. It is a heterogeneous breast cancer subtype with a poor prognosis. Given these negative features, there is a need for new treatment options beyond conventional chemotherapy in both the early stage and palliative setting. Impressive results have been reported with antibody-drug conjugates (ADCs) that link a cytotoxic payload to a monoclonal antibody, such as sacituzumab govitecan and trastuzumab deruxtecan, in the metastatic stage. The focus of this review is to discuss completed and ongoing trials involving ADCs in TNBC.

Trop-2 as a Therapeutic Target in Breast Cancer

The emergence of Trop-2 as a therapeutic target has given rise to new treatment paradigms for the treatment of patients with advanced and metastatic breast cancer. Trop-2 is most highly expressed in triple negative breast cancer (TNBC), but the receptor is found across all breast cancer subtypes. With sacituzumab govitecan, the first FDA-approved, Trop-2 inhibitor, providing a survival benefit in patients with both metastatic TNBC and hormone receptor positive breast cancer, additional Trop-2 directed therapies are under investigation. Ongoing studies of combination regimens with immunotherapy, PARP inhibitors, and other targeted agents aim to further harness the effect of Trop-2 inhibition. Current investigations are also underway in the neoadjuvant and adjuvant setting to evaluate the therapeutic benefit of Trop-2 inhibition in patients with early stage disease. This review highlights the significant impact the discovery Trop-2 has had on our patients with heavily pretreated breast cancer, for whom few treatment options exist, and the future direction of novel Trop-2 targeted therapies.

Features of inhalant allergy on nasal endoscopy: a systematic review and meta-analysis

BACKGROUND

Nasal endoscopy is increasingly accessible to ENT surgeons. The characteristics of the allergic upper airway are not well recognised.

METHODOLOGY

MEDLINE (1946-2021), EMBASE (1974-2021), and the Cochrane Library were searched on 16th November 2021 to identify articles that reported endoscopic findings of patients with documented allergy who had undergone nasal endoscopy. The review followed the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. Meta-analysis was performed by pooling sensitivities and specificities using the hierarchical summary receiver operating characteristics model.

RESULTS

A total of 4108 articles were identified, of which 15 manuscripts met the inclusion criteria. The included studies involved 4660 patients who had undergone nasal endoscopy. Middle turbinate (diffuse/polypoid) oedema (sensitivity 58.0%, specificity 84.5%), watery secretions (sensitivity 65.7%, specificity 76.5%), inferior turbinate hypertrophy (sensitivity 86.2%, specificity 32.2%), and unspecified turbinate hypertrophy (sensitivity 82.0%, specificity 42.9%) were identified as the features with the highest predictive value of inhalant allergy.

CONCLUSIONS

Diffuse or polypoid oedema of the middle turbinate or watery secretions seen on nasal endoscopy can be a useful adjunct in the identification and diagnosis of inhalant allergy. These clinical features should be part of the diagnostic workup for patients that includes a clinical history and surrogate markers of allergic sensitisation from the skin and serum.

Outcomes of patients with oropharyngeal squamous cell carcinoma treated with induction chemotherapy followed by concurrent chemoradiation compared with those treated with concurrent chemoradiation

BACKGROUND

Induction chemotherapy (IC) has been associated with a decreased risk of distant metastasis in locally advanced head and neck squamous cell carcinoma. However, its role in the treatment of oropharyngeal squamous cell carcinoma (OPSCC) is not well established.

METHODS

The outcomes of patients with OPSCC treated with IC followed by concurrent chemoradiation (CRT) were compared with the outcomes of those treated with CRT alone. The primary outcome was overall survival (OS), and the secondary end points were the times to locoregional and distant recurrence.

RESULTS

In an existing database, 585 patients met the inclusion criteria: 137 received IC plus CRT, and 448 received CRT. Most patients were positive for human papillomavirus (HPV; 90.9%). Patients receiving IC were more likely to present with a higher T stage, a higher N stage, and low neck disease. The 3-year OS rate was significantly lower in patients receiving IC (75.7%) versus CRT alone (92.9%). In a multicovariate analysis, receipt of IC (adjusted hazard ratio [aHR], 3.4; P < .001), HPV tumor status (aHR, 0.36; P = .002), and receipt of concurrent cetuximab (aHR, 2.7; P = .002) were independently associated with OS. The risk of distant metastasis was also significantly higher in IC patients (aHR, 2.8; P = .001), whereas an HPV-positive tumor status (aHR, 0.44; P = .032) and completion of therapy (aHR, 0.51; P = .034) were associated with a lower risk of distant metastasis. In HPV-positive patients, IC remained associated with distant metastatic progression (aHR, 2.6; P = .004) but not OS.

CONCLUSIONS

In contrast to prior studies, IC was independently associated with worse OS and a higher risk of distant metastasis in patients with OPSCC. Future studies are needed to validate these findings.

When the World Throws You a Curve Ball: Lessons Learned in Breast Cancer Management

In the care of patients with operable breast cancer, there has been a shift toward increasing use of neoadjuvant therapy. There are benefits to neoadjuvant therapy, such as monitoring for response, as well as an increased rate of breast conservation and reduction of potential morbidity associated with breast surgery, including axillary management. Among patients with highly proliferative tumors, such as HER2-positive or triple-negative breast cancer, those with residual disease are at higher risk of recurrence, which informs the recommended systemic therapy in the adjuvant setting. For instance, in patients with residual disease after neoadjuvant chemotherapy and HER2-targeted therapy, there is a role for adjuvant trastuzumab emtansine for those with residual disease at the time of surgery. The same holds true regarding the role of adjuvant capecitabine in patients with residual disease after neoadjuvant chemotherapy. With the added complexities of treating patients in the era of the COVID-19 outbreak, additional considerations are critical, including initiation of surgery within an appropriate time from completion of neoadjuvant therapy. National consensus guidelines on time to surgery must be developed to improve measurement and comparison across systems. In addition, there is emerging radiation treatment management research addressing a number of factors, including hypofractionation, role of proton beam therapy, safe omission of radiotherapy, and preoperative radiotherapy with or without drug combination. In this article, the multidisciplinary approach of treating patients with operable breast cancer is highlighted, with updates and future considerations described.

Subjective functional outcomes in oropharyngeal cancer treated with induction chemotherapy using the MD Anderson Symptom Inventory (MDASI)

OBJECTIVES

Evaluate the use of induction chemotherapy (IC) in oropharyngeal cancer (OPC) and its impact on subjective functional outcomes using a validated MD Anderson Symptom Inventory-Head and Neck (MDASI-HN) survey tool.

METHODS

A single institution retrospective review of OPC patients who received IC, including reasons given for using IC, regimens employed, responses, and patient-reported outcomes (PRO). The latter included pain, distress, dysphagia, xerostomia, and feeding tube placement and dependency. PRO's were assessed using the validated MD Anderson Symptom Inventory-Head and Neck (MDASI-HN) conducted at baseline, during treatment, and at six-month follow up.

RESULTS

One hundred and twenty-five patients were evaluable. They were more likely to have large primary and/or bulky or low neck nodal disease as a reason for IC. A taxane-containing regimen was most common. Primary tumor response was seen in 83.2% and the nodal response in 81.6%. Pain and xerostomia improved with IC, dysphagia was not adversely affected with IC. These symptoms all increased with consolidation chemoradiotherapy (CRT) but returned to baseline by 6 months post treatment. Feeding tube placement did not increase with IC but did with CRT, most patients were no longer feeding tube dependent at 6 months.

CONCLUSION

This retrospective review of subjective functional outcomes, especially swallowing and feeding tube dependency, using the MDASI survey tool in 125 oropharyngeal cancer patients with large primary tumors and/or bulky adenopathy treated predominantly with platinum-taxane based induction chemotherapy showed that such outcomes were not adversely impacted. While not standard, such approach may be beneficial in such patients.

LEVEL OF EVIDENCE

2.

Unique Patterns of Distant Metastases in HPV-Positive Head and Neck Cancer

BACKGROUND

HPV-positive head and neck squamous cell carcinoma (HPV+ HNSCC) demonstrates favorable outcomes compared to HPV-negative SCC, but distant metastases (DM) still occur. The pattern of DM in HPV+ HNSCC is unclear.

METHODS

1,494 HNSCC patients were treated from 2006 to 2012. Recurrence time and metastatic sites in HPV+ HNSCC (Group 1) were compared to patients with HPV-negative/unknown cancers arising in the hypopharynx, larynx, or glottis (Group 2) as well as to patients with HPV-negative/unknown cancers in theoral cavity, oropharynx, hard palate, or tonsil (Group 3).

RESULTS

7/109 (6.4%) patients with HPV+ HNSCC developed DM. The median time to metastases was 11 months. At a median follow-up of 18-25 months, there was no difference in the overall rate of DM for the HPV+ HNSCC group compared to Group 2 (HPV-/unknown) (p = 0.21) and Group 3 (HPV-/unknown) (p = 0.13). There was a significant difference in the rate of DM to the lung in the HPV+ HNSCC group compared to Group 2 (HPV-/unknown) (p = 0.012) and Group 3 (HPV-/unknown) (p = 0.002).

CONCLUSIONS

There was no observed difference in the time to development of DM between the HPV-/unknown and HPV+ HNSCC groups. However, the HPV+ HNSCC group showed a higher rate of DM to the lung compared to the HPV-/unknown -HNSCC group (p = 0.002).

Characteristics of macrolide responders in persistent post-surgical rhinosinusitis

INTRODUCTION

The anti-inflammatory effects of long term low dose macrolide therapy have shown benefit in the management of diffuse panbronchiolitis. Dramatic responses to macrolide in the upper airway are seen but our understanding of the patient phenotype predisposing to macrolide response in chronic rhinosinusitis (CRS) is poor.

METHODS

A case control study was performed in a tertiary level rhinology practice of consecutive chronic rhinosinusitis patients placed on a 3-month low dose macrolide therapy after failing at least 3 months of corticosteroid irrigation therapy post-endoscopic sinus surgery. Patients were defined as a macrolide responder when having near normal endoscopy after a 3-month period of clarithromycin treatment. Patient characteristics of smoking, asthma, atopy status, revision surgery, symptom severity (SNOT-22) along with biomarkers from serum and tissue histopathology results were compared between groups.

RESULTS

Of twenty-eight consecutive macrolide treated patients, 19 responders were compared to 9 non-responders. The groups were similar in age, female gender, non-smoking, asthma, and atopy. Macrolide response was associated with a lack of tissue eosinophilia (more than 10/HPF) and lower serum eosinophilia. Neutrophil expression was similar in tissue and serum. Squamous metaplasia was overexpressed in non-responders.

CONCLUSION

Low tissue and serum eosinophilia, and absence of tissue squamous metaplasia may predict a CRS phenotype suitable to a trial of long-term macrolide therapy when surgery and topical therapy has failed.

Airflow and symptom outcomes between allergic and non-allergic rhinitis patients from turbinoplasty

BACKGROUND

Inferior turbinate procedures are applied to relieve medically refractory nasal obstruction. However, the nature of congestion differs between allergic(AR) and non-allergic rhinitis(NAR). This study compares surgical outcomes between AR and NAR patients.

METHODOLOGY

A case-control study of patients undergoing turbinate with or without septoplasty surgery for nasal obstruction was performed. Patient reported outcomes were: nasal obstruction, global nasal function(GNF), and sino-nasal outcome test(SNOT-22) with rhinitis, facial symptom, sleep and psychological sub-scores. Nasal peak inspiratory flow(NPIF) assessed nasal airflow. Measurements were obtained preoperatively and 3 months postoperatively.

RESULTS

190 patients were assessed. AR had worse obstruction and worse GNF. All outcomes improved post-surgery; nasal obstruction, GNF, SNOT-22, rhinitis-symptoms, facial-symptoms, sleep-function, psychological-function and NPIF. GNF improvement was greater in AR. NPIF improvement was similar between groups.

CONCLUSIONS

Both AR and NAR patients gained benefit from surgery to relieve nasal obstruction. AR patients demonstrate greater improvement in GNF score but allergy management may contribute to this.

Periostin as a marker of mucosal remodelling in chronic rhinosinusitis

BACKGROUND

Although extracellular matrix (ECM) proteins are associated with irreversible lower airway changes, the relationship with upper airway remodelling which occurs during chronic rhinosinusitis (CRS) is poorly understood. This study assessed the expression of ECM proteins periostin, fibulin-1, fibronectin and collagenIV in nasal mucosa of patients with and without histologic features of remodelling.

METHODS

A cross-sectional study of sinonasal mucosal biopsies taken from patients, undergoing surgery for CRS was performed, where patients were grouped according to remodelling, defined by basement membrane thickening (BMT over 7.5 micrometer) and subepithelial fibrosis. An overall view and three random fields of immunostained tissue sections that included epithelium, basement membrane and submucosa, were imaged using Zeiss Zen software. The area and intensity of positive staining were scored by two blinded observers, using a 12-point ordinal scale of weak to strong.

RESULTS

65 patients (47.6 +/- 13.4years, 44.6% female) were assessed. Patients were grouped as controls 26.2%, BMT/no fibrosis 38.5% or BMT and fibrosis 33.8%. Stronger grade of periostin expression was associated with remodelling changes and tissue eosinophilia over 10/HPF. Fibulin-1, fibronectin and collagenIV did not differ.

CONCLUSION

Periostin expression was associated with the presence of BMT, fibrosis and tissue eosinophilia and may identify patients undergoing remodelling changes.

Periostin as a marker of mucosal remodelling in chronic rhinosinusitis

BACKGROUND

Although extracellular matrix (ECM) proteins are associated with irreversible lower airway changes, the relationship with upper airway remodelling which occurs during chronic rhinosinusitis (CRS) is poorly understood. This study assessed the expression of ECM proteins periostin, fibulin-1, fibronectin and collagenIV in nasal mucosa of patients with and without histologic features of remodelling.

METHODS

A cross-sectional study of sinonasal mucosal biopsies taken from patients, undergoing surgery for CRS was performed, where patients were grouped according to remodelling, defined by basement membrane thickening (BMT over 7.5 micrometer) and subepithelial fibrosis. An overall view and three random fields of immunostained tissue sections that included epithelium, basement membrane and submucosa, were imaged using Zeiss Zen software. The area and intensity of positive staining were scored by two blinded observers, using a 12-point ordinal scale of weak to strong.

RESULTS

65 patients (47.6 +/- 13.4years, 44.6% female) were assessed. Patients were grouped as controls 26.2%, BMT/no fibrosis 38.5% or BMT and fibrosis 33.8%. Stronger grade of periostin expression was associated with remodelling changes and tissue eosinophilia over 10/HPF. Fibulin-1, fibronectin and collagenIV did not differ.

CONCLUSION

Periostin expression was associated with the presence of BMT, fibrosis and tissue eosinophilia and may identify patients undergoing remodelling changes.

Modified Lund Mackay Postoperative Endoscopy Score for defining inflammatory burden in chronic rhinosinusitis

OBJECTIVE

The Lund Mackay Postoperative Endoscopy Score (LMES) for chronic rhinosinusitis (CRS) is a poor measure of the patient experience. A proposed Modified Lund Mackay Postoperative Endoscopy Score (MLMES) aims to better describe the inflammatory burden in CRS.

METHODS

A prospective study on CRS patients having endoscopic sinus surgery (ESS) was conducted. Endoscopy was recorded at the 6th and the 12th week post-op. The MLMES recorded changes in mucosa, mucus and purulence for each of the maxillary, ethmoid, sphenoid, frontal sinuses and olfactory fossa in post-ESS cavities. The correlation between MLMES and visual analogue scale of total rhinosinusitis symptoms, global anchor score of nasal function, Sino-Nasal Outcome Test 22 (SNOT-22) and nasal symptom score was analyzed. The inter-observer reliability, intra-observer reliability and correlation between the change in MLMES and in subjective measures were also investigated.

RESULTS

Thirty patients were assessed. The MLMES significantly correlated with visual analogue scale, SNOT-22, global anchor and nasal symptom score. The change in MLMES correlated with the change in SNOT-22 and nasal symptom score. The inter-observer and intra-observer reliability were excellent.

CONCLUSION

Objectives measurements for post-ESS patients can be reconsidered to represent the cumulative inflammatory burden of all sinuses. The proposed MLMES represents total sinus inflammatory burden and correlates well with patient reported outcome measures.

The impact of bitter taste receptor genetics on culturable bacteria in chronic rhinosinusitis

BACKGROUND

Extra-oral bitter taste receptors have been associated with innate bacterial defence mechanisms. Genetic variation in T2R38 functionality has been shown to be associated with susceptibility to upper respiratory tract infections and chronic rhinosinusitis (CRS). We sought to independently assess the influence of bitter taste receptor genotype on the presence of culturable bacteria in the sinuses.

METHODOLOGY

A cross-sectional analysis of patients with CRS undergoing surgery was performed. Middle meatal nasal swabs were sent for microbiological evaluation at the time of the procedure. Mucosal biopsies were taken and sent for bitter taste receptor genotype analysis. Sequencing of 3 polymorphisms in the TAS2R38 gene was performed to identify genotypes as super-tasters (PAV/PAV), non-tasters (AVI/AVI) or heterozygous expression (PAV/AVI). The presence of culturable organisms and common pathogens were compared with bitter taste receptor genotypes.

RESULTS

25 patients (age 52.4 +/- 18.28 years, 51% female) were assessed. Super-tasters comprised 16% of the group, 24% were non-tasters and 48% had heterozygous expression. A cultured pathogen was grown in 48% of patients; 32% gram-positive, 20% gram-negative, 28% grew Staphylococcus aureus and 12% Pseudomonas aeruginosa. A non-taster genotype was predictive of colonised pathogens. Tissue eosinophilia (more than 10 HPF) was seen in 48%.

CONCLUSION

Even in a small sample of patients with CRS, non-taster T2R38 genotype appears to predict the presence of culturable bacteria colonising the sinus cavity at the time of surgery for their condition. A genetic link to patients more likely to become infected is likely.

Association of gastro-oesophageal reflux and chronic rhinosinusitis: systematic review and meta-analysis

INTRODUCTION

Gastro-oesophageal reflux disease (GORD) has been implicated in the development of chronic rhinosinusitis (CRS). The association of GORD with CRS is systematically assessed from the medical literature.

METHODOLOGY

Embase and MEDLINE were searched using a comprehensive strategy limited to English language and Human subjects. Any study with original data on the experimental, diagnostic, treatment or prognostic association of CRS with GORD was included. Studies without a control group, case reports and review articles were excluded.

RESULTS

The search returned 958 records, with an additional 10 found from bibliographic lists; this produced 32 studies. The included studies (n=32) consisted of studies reporting pathogenic factors (n=20), epidemiological association (n=8), prognostic interactions (n=3), and a combination of these outcomes (n=1). Potential pathogenic roles for GORD in CRS were supported; CRS subjects had greater prevalence of intranasal Helicobacter pylori and acid reflux than subjects without CRS. CRS is more prevalent in GORD sufferers than those without GORD. Evidence is conflicting for GORD as a factor in CRS treatment failure.

CONCLUSION

The results support a significant association of GORD with CRS. Physicians should be cognizant of the potential for acid and non-acid reflux as a driving factor in CRS.

Intranasal corticosteroids do not affect intraocular pressure or lens opacity: a systematic review of controlled trials

BACKGROUND

Intranasal corticosteroids (INCS) are prescribed for the long-term prophylactic treatment of inflammatory upper airway conditions. Although some systemic absorption can occur via topical routes, the clinical relevance is controversial. The effects of orally administered corticosteroids on intraocular pressure (IOP) and lens opacity (LO) are well established, but the impact of the INCS is less well defined. This study aims to systematically review the literature for evidence of adverse occular events with INCS use.

METHODOLOGY

A systematic review of literature from Medline and Embase databases (January 1974 to 21st of November 2013) was performed. Using the PRISMA guidelines, all controlled clinical trials of patients using INCS, that reported original measures of IOP, LO, glaucoma or cataract incidences were included. Studies with adjuvant administration of oral, inhaled and intravenous steroids were excluded.

RESULTS

665 articles were retrieved with 137 were considered for full-text review. Of these, 116 (85%) were literature reviews and two were case reports. 19 studies (10 RCTs, 1 case-control, 8 case series) were included for the qualitative review, of which 18 reported data on IOP and 10 on cataract/LO. None (n=0) of the 10 RCT reporting data on glaucoma or IOP demonstrated changes in IOP compared to control. Also none (n=0) of the 6 RCTs reporting cataract or lens opacity demonstrated changes compared to control.

CONCLUSION

Data from studies with low levels of bias, do not demonstrate a clinically relevant impact of INCS on neither ocular pressure, glaucoma, lens opacity nor cataract formation.

Group 2 innate lymphoid cells (ILC2s) are increased in chronic rhinosinusitis with nasal polyps or eosinophilia

BACKGROUND

Chronic rhinosinusitis (CRS) is a heterogeneous disease with an uncertain pathogenesis. Group 2 innate lymphoid cells (ILC2s) represent a recently discovered cell population which has been implicated in driving Th2 inflammation in CRS; however, their relationship with clinical disease characteristics has yet to be investigated.

OBJECTIVE

The aim of this study was to identify ILC2s in sinus mucosa in patients with CRS and controls and compare ILC2s across characteristics of disease.

METHODS

A cross-sectional study of patients with CRS undergoing endoscopic sinus surgery was conducted. Sinus mucosal biopsies were obtained during surgery and control tissue from patients undergoing pituitary tumour resection through transphenoidal approach. ILC2s were identified as CD45(+) Lin(-) CD127(+) CD4(-) CD8(-) CRTH2(CD294)(+) CD161(+) cells in single cell suspensions through flow cytometry. ILC2 frequencies, measured as a percentage of CD45(+) cells, were compared across CRS phenotype, endotype, inflammatory CRS subtype and other disease characteristics including blood eosinophils, serum IgE, asthma status and nasal symptom score.

RESULTS

35 patients (40% female, age 48 ± 17 years) including 13 with eosinophilic CRS (eCRS), 13 with non-eCRS and 9 controls were recruited. ILC2 frequencies were associated with the presence of nasal polyps (P = 0.002) as well as high tissue eosinophilia (P = 0.004) and eosinophil-dominant CRS (P = 0.001) (Mann-Whitney U). They were also associated with increased blood eosinophilia (P = 0.005). There were no significant associations found between ILC2s and serum total IgE and allergic disease. In the CRS with nasal polyps (CRSwNP) population, ILC2s were increased in patients with co-existing asthma (P = 0.03). ILC2s were also correlated with worsening nasal symptom score in CRS (P = 0.04).

CONCLUSION AND CLINICAL RELEVANCE

As ILC2s are elevated in patients with CRSwNP, they may drive nasal polyp formation in CRS. ILC2s are also linked with high tissue and blood eosinophilia and have a potential role in the activation and survival of eosinophils during the Th2 immune response. The association of innate lymphoid cells in CRS provides insights into its pathogenesis.

Nasal peak inspiratory flow (NPIF) as a diagnostic tool for differentiating decongestable from structural nasal obstruction

BACKGROUND

Identifying the cause of nasal obstruction is critical before surgical intervention. Structural nasal obstruction, due to nasal valve stenosis, is unlikely to benefit from simple septoplasty and turbinate reduction. This study assesses changes in nasal peak inspiratory flow (NPIF) as a tool for discriminating decongestable versus structural obstruction.

METHODOLOGY

Cross-sectional study of patients undergoing nasal airflow assessment was performed. Rhinomanometry, nasal obstruction visual analogue scores (VAS) and NPIF were performed pre- and post-decongestion. Population groups were defined with decongestable or structural obstruction by relative post-decongestion changes in airways resistance and symptoms.

RESULTS

Fifty two patients were assessed, 24 with decongestable, 28 with structural obstruction. Pre- and post-decongestion NPIF were similar between groups. Absolute and percentage NPIF change were larger with decongestable versus structural obstruction. Sensitivity and specificity for predicting decongestable obstruction were 75.0% and 60.7% for NPIF increase >20 L/min; 75.0% and 64.3% for NPIF increase >20%. The respective positive predictive values were 62.1% and 64.3%.

CONCLUSION

NPIF increase after decongestion is larger with decongestable than structural nasal obstruction. NPIF alone cannot discriminate the two conditions and does not replace more formal assessment.

Imidazoline use in sinonasal surgery

The nasal mucosa is very vascular, receiving more blood flow per cubic centimeter of tissue than does muscle, brain or liver (Drettner and Aust, 1974; [1]). This vascularity can present a major problem during sinus surgery. Surgeons routinely use topical vasoconstrictors in endoscopic sinus surgery however, the optimal regimen is not clear. Imidazoline nasal sprays are often used up to 1hour before sinonasal surgery to aid in intraoperative vasoconstriction. After the induction of anaesthesia, epinephrine-based topical and submucosal preparations are subsequently administered to further enhance vasoconstriction. Imidazolines are non-selective, partial alpha adrenoceptor agonists with a higher affinity, yet lower potency, for alpha adrenoceptors when compared to epinephrine. It is hypothesized that imidazolines block the action of epinephrine on the alpha adrenoceptors of the nasal mucosa resulting in less vasoconstriction, and a poorer intra-operative field, when compared to the use of epinephrine alone. This paper hypothesizes that preoperative imidazoline administration may adversely affect optimal intra-operative vasoconstriction.

Osteitic bone: a surrogate marker of eosinophilia in chronic rhinosinusitis

BACKGROUND

Causes of osteitis in chronic rhinosinusitis (CRS) other than previous surgery are poorly defined. Patients with eosinophilic CRS (ECRS) have more severe disease and poorer outcomes despite repeated surgery. Associations between osteitis and markers of ECRS are not well described.

METHODS

A cross-sectional study of CRS patients undergoing sinus surgery was conducted. Osteitis was scored radiologically using previously published measures. Associations between osteitis and histopathology, symptoms, endoscopy, CT mucosal score and seromarkers were analyzed.

RESULTS

Eighty-eight patients were assessed of whom forty-five had osteitis. Patients undergoing revision surgery recorded higher osteitis scores. Patients with mucosal eosinophilia had higher osteitis score than those without. Patients with osteitis had higher serum eosinophil. Similar relationships were also found in primary surgery. Osteitis was associated with endoscopic and radiologic, but not symptomatic disease severity.

CONCLUSIONS

Osteitis is associated with tissue and serum eosinophilia in both patients with and without prior surgery. Patients with these features may benefit from post-operative corticosteroid therapy to prevent osteitis.

Rapid HIV testing using Determine™ HIV 1/2 antibody tests: is there a difference between the visual appearance of true- and false-positive tests?

HIV point-of-care tests (POCTs) give occasional false positive results, causing unnecessary patient anxiety. We aimed to elicit whether false- and true-positive POCTs differed visually. Seventeen false- and 17 true-positive serum samples were randomized into pairs, comprising one false- and one true-positive sample. Two independent readers identified each POCT as negative or positive and compared line strength between pairs. Six further readers graded line strength, 0-5, from POCT photographs. All true-positive samples were identified positive and 8/17 false-positive samples negative, on repeat testing of stored sera. Eight out of the 9 remaining false-positive tests were described as having weaker pigment uptake than their paired true-positive POCT. Mean grade of line strength was 4.2 in true- and 0.9 in false-positive samples, on photographic evaluation. These results suggest false-positive POCTs may differ visually from true-positive POCTs. If larger studies confirm these findings, we may be able to alleviate anxiety in low risk patients with faintly positive POCTs awaiting their confirmatory laboratory result, where the possibility of a false-positive result could be emphasized.

Risk of prevalent HIV infection associated with incarceration among injecting drug users in Bangkok, Thailand: case-control study

OBJECTIVES

To identify risks for HIV infection related to incarceration among injecting drug users in Bangkok, Thailand.

DESIGN

Case-control study of sexual and parenteral exposures occurring before, during, and after the most recent incarceration.

SETTING

Metropolitan Bangkok.

PARTICIPANTS

Non-prison based injecting drug users formerly incarcerated for at least six months in the previous five years, with documented HIV serostatus since their most recent release; 175 HIV positive cases and 172 HIV negative controls from methadone clinics.

MAIN OUTCOME MEASURE

Injection of heroin and methamphetamine, sharing of needles, sexual behaviour, and tattooing before, during, and after incarceration.

RESULTS

In the month before incarceration cases were more likely than controls to have injected methamphetamine and to have borrowed needles. More cases than controls reported using drugs (60% v 45%; P=0.005) and sharing needles (50% v 31%; P<0.01) in the holding cell before incarceration. Independent risk factors for prevalent HIV infection included injection of methamphetamine before detention (adjusted odds ratio 3.3, 95% confidence interval 1.01 to 10.7), sharing needles in the holding cell (1.9, 1.2 to 3.0), being tattooed while in prison (2.1, 1.3 to 3.4), and borrowing needles after release (2.5, 1.3 to 4.4).

CONCLUSIONS

Injecting drug users in Bangkok are at significantly increased risk of HIV infection through sharing needles with multiple partners while in holding cells before incarceration. The time spent in holding cells is an important opportunity to provide risk reduction counselling and intervention to reduce the incidence of HIV.

High-speed GC and GC/time-of-flight MS of lemon and lime oil samples

The high-speed GC separation and MS characterization of lime oil and lemon oil samples using programmable column selectivity and time-of-flight mass spectrometry is described. The volatile essential oils are separated on a series-coupled (tandem) column ensemble consisting of a polar trifluoropropylmethyl polysiloxane column and a nonpolar 5% phenyl dimethyl polysiloxane column. Both columns are 7 m long. A 50 degrees C/min linear temperature ramp from 50 to 200 degrees C is used, giving an analysis time of approximately 2.5 min. A time-of-flight MS with time array detection and automated peak finding and characterization software was used to identify 50 components in lime oil samples and 25 components in lemon oil samples. Despite numerous cases of extensive peak overlap, spectral deconvolution software was very successful in the characterization of most overlapping peaks. For cases where a more complete chromatographic separation is desirable, the tandem column ensemble is operated in the first-column stop-flow mode to enhance the separation of selected overlapping clusters of peaks. A valve between the junction point of the tandem column ensemble and a source of carrier gas at the GC inlet pressure is opened for 2-5-s intervals to stop the flow of carrier gas in the first column. This is used to increase the separation of target component groups that overlap in the ensemble chromatogram without first-column stop-flow operation. This procedure is used to isolate the peak for limonene, the largest peak in the analytical-ion chromatogram of both the lime and lemon oil samples.

High-speed GC and GC/MS with a series-coupled column ensemble using stop-flow operation

A pneumatically actuated valve is used to connect the junction point of a series-coupled column ensemble to a ballast chamber containing carrier gas at the ensemble inlet pressure in order to periodically stop the carrier gas flow in the first column. When the valve is opened, mixture components, which have migrated across the column junction, are accelerated toward a time-of-flight mass spectrometer that is used as an ensemble detector. Mixture components, which are still in the first column, are frozen in position. This allows for the insertion of time windows into the ensemble chromatogram that can aid in the separation of some overlapping component peaks. The capillary column ensemble (0.18-mm i.d. x 0.18-microm film thickness) consists of a 7.0-m length of polar, (trifluoropropyl)methyl polysiloxane column followed by a 7.0-m length of nonpolar dimethyl polysiloxane column. A flame ionization detector located at the column junction point is used to monitor a portion of the effluent from the first column in order to determine the valve timing sequence needed to enhance the separation of component pairs that are separated by the first column but coelute from the column ensemble. When one of the components of a targeted pair has crossed the junction but the other component is still in the first column, the valve is opened, typically for 1-5 s. The stop-flow system is used to enhance the separation of a mixture containing some common essential oil components and a mixture containing some common pesticides.

Band-trajectory model for temperature-programmed series-coupled column ensembles with pressure-tunable selectivity

A model and a spreadsheet algorithm is described for the prediction of solute-band migration trajectories in a series-coupled combination of two capillary GC columns with pressure-tunable and -programmable selectivity and operated under temperature-programmed conditions. The model takes into account the acceleration of carrier gas in the two columns as a result of decompression effects, the deceleration of carrier gas as a result of the increase in viscosity during temperature programming, the decrease in solute retention factors with increasing temperature during the temperature program, the differences in retention factors for the two columns, and programmed changes in the carrier-gas flow rates in the two columns during selectivity programming. In the model, the 20-meter-long column ensemble is divided into 1-cm-long intervals, and the carrier-gas velocity and column temperature are assummed to be constant in any interval. Migration times for all of the mixture solutes are computed for each column interval, and the solute-band positons in the column ensemble are plotted versus the running sum of these migration times to obtain band trajectory plots. The sum of these migration times for all 2,000 intervals gives the ensemble retention times for the solutes. Isothermal retention factors (k) for all of the mixture components at various column temperatures (Tc) are used as imput to the algorithm. Slope and intercept values of In(k) vs 1/Tc plots are used in the algorithm. General features of the model are tested using a mixture of C12-C24 normal alkanes. A mixture of polar and nonpolar compounds is used to test the utility of the model for the predicition of peak separations and retention times with pressure-tunable and -programmable selectivity. Good agreement is observed in all cases.

A tandem column ensemble with an atmospheric pressure junction-point vent for high-speed GC with selective control of peak-pair separation

A series-coupled (tandem) ensemble of two capillary GC columns using different stationary phases and a pneumatically actuated low-volume valve connecting the column junction point to an atmospheric-pressure vent line is used to adjust the ensemble separation of selected pairs of target compounds. The valve is normally closed, and the pressure at the column junction point assumes the value that would occur in the absence of any other connections. The valve can be opened for brief periods of time, thus producing pulses of atmospheric pressure at the column junction point. If a component pair is separated by the first column but coelutes from the column ensemble, the ensemble separation can be increased if a pulse occurs when one of the components has migrated across the column junction but the second component is still on the first column. All of the mixture components that are on the same column during the time that the valve is open (pulse duration) will be shifted to either larger or smaller retention times, but the pattern of peaks (elution order) for these components from the column ensemble will be relatively unaffected by the pressure pulse. Multiple pulses can be used to enhance the separation of different component pairs, which sequentially reach the column junction point. Performance of the valve-operated system is described. Time-of-flight mass spectrometry with time-array detection is used to examine the effects of pulse duration on the separation achieved for different component pairs.

Pulsed flow modulation for high-speed GC using a pressure-tunable column ensemble

A computer-driven pressure controller is used to deliver pressure pulses to the junction point of two series-coupled columns using different stationary-phase chemistries. The column ensemble consists of a trifluoropropylmethyl polysiloxane column followed by a dimethyl polysiloxane column. Each pressure pulse causes a differential change in the carrier gas velocities in the two columns, which lasts for the duration of the pulse. A pressure pulse is used to selectively increase the separation of a component pair that is separated by the first column but coelutes from the series-coupled ensemble. If both components are on the same column when the pulse is applied, a small change in the ensemble separation occurs. If one component of the pair is on the first column and the other component is on the second column, a pressure pulse can result in a much larger change in the ensemble separation for the component pair. A model with a spreadsheet algorithm is used to predict the effects of a pressure pulse on the trajectories of component bands on the column ensemble. The effect of the initiation time of a pressure pulse is investigated for a two-component mixture that coelutes from the column ensemble. For the case where the entire pressure pulse occurs when one of the components is on the first column and the other component is on the second column, the peak separation from the ensemble increases nearly linearly with the product of the pressure pulse amplitude and the pulse duration. Peak shape artifacts are observed if the pressure pulse occurs when a solute band is migrating across the column junction point.

Hrs-2 is an ATPase implicated in calcium-regulated secretion

Associations between proteins present on neurotransmitter-containing vesicles and on the presynaptic membrane are thought to underlie docking and fusion of synaptic vesicles with the plasma membrane, which are obligate steps in regulated neurotransmission. SNAP-25 resides on the plasma membrane and interacts with syntaxin (a plasma membrane t-SNARE) and VAMP (a vesicle v-SNARE) to form a core protein complex thought to be an intermediate in a biochemical pathway that is essential for vesicular transport. We have now characterized a protein, Hrs-2, that interacts with SNAP-25. The binding of Hrs-2 to SNAP-25 is inhibited by calcium in the physiological concentration range that supports synaptic transmission. Furthermore, Hrs-2 binds and hydrolyses nucleoside triphosphates with kinetics that suggest that ATP is the physiological substrate for this enzyme. Hrs-2 is expressed throughout the brain and is present in nerve terminals. Moreover, recombinant Hrs-2 inhibits calcium-triggered 3H-noradrenaline release from permeabilized PC12 cells. Our results suggest a role for Hrs-2 in regulating secretory processes through calcium- and nucleotide-dependent modulation of vesicle-trafficking protein complexes.

Synovial metastasis: diagnosis by fine-needle aspiration cytologic investigation

Synovial metastases are a rare occurrence. Only 28 cases have been reported in the literature, 10 of which were diagnosed by fluid cytologic evaluation. We discuss 2 additional cases in which the diagnosis was made by fine-needle aspiration cytologic investigation. The first case is of a 47-yr-old man with small-cell carcinoma of the lung metastatic to the right knee joint; the second is of a 71-yr-old man with non-Hodgkin's mixed-cell nodular lymphoma also involving the right knee joint. The clinical features of these cases are similar to previously published instances of secondary synovial tumor, namely in regard to sex distribution (14 male and 16 female patients), age range (13-96 yr, mean 59 yr), and histologic types (adenocarcinoma, 13 cases; squamous-cell carcinoma, 4; lymphoma, 3; renal clear-cell carcinoma, 3; unknown origin, 2; rhabdomyosarcoma, 1; melanoma, 1; chordoma, 1; pulmonary clear-cell carcinoma, 1; and Ewing's sarcoma, 1). The condition usually has poor prognosis, with average patient survival of < 5 mo.

Comparison of enteral and intramuscular vitamin A supplementation in preterm infants

Vitamin A deficiency associated with preterm delivery is not readily reversible using the recommended supplement of 1500 IU per day. It has been reported that 2000 IU of intramuscular vitamin A administered on alternate days for 28 days will correct the deficiency. The objective of this study was to compare this regime with the practice in our nursery of giving 5000 IU of vitamin A per day with the early introduction of feeds. The vitamin A status of ten preterm infants (mean gestation 30.5 weeks) who received intramuscular vitamin supplementation was compared with that of nine infants (mean gestation 30.7 weeks) given enteral vitamin A. Vitamin A status was evaluated on the 32nd day of life using plasma retinol and retinol-binding protein (RBP) concentrations and a modified relative dose response (RDR) test. Plasma retinol and RBP concentrations were similar in the two groups shortly after birth revealing vitamin A deficiency. By the 32nd day of life, plasma retinol and RBP concentrations had risen significantly in both groups and in 70% the modified RDR was normal. Differences between the groups were not observed irrespective of the method of vitamin A administration. None of the infants developed clinical or biochemical vitamin A toxicity. In most preterm infants who tolerate feeds, vitamin A deficiency can be corrected safely by supplementing the feeds with 5000 IU of vitamin A per day.