Risk of malignancy in incidental oropharyngeal lesions exhibiting fluorodeoxyglucose uptake which proceed to tissue biopsy

BACKGROUND

Utilization of positron emission tomography/computed tomography (PET/CT) with fluorodeoxyglucose is increasing in use for a variety of indications, including surveillance of cancer patients. There is a paucity of evidence pertaining to the significance of incidental PET-avid oropharyngeal lesions. This study aims to examine the clinical and radiological features of these incidental oropharyngeal lesions in patients undergoing PET for indications other than head and neck cancer.

METHODS

Retrospective cohort study of three Australian tertiary hospitals, from 2015 to 2021, on adult patients undergoing biopsy of incidental PET-avid oropharyngeal lesions. Primary outcome of interest was the incidence of malignancy. Patients with a previous history of, or undergoing investigations for, head and neck cancer were excluded.

RESULTS

Thirty-one patients were included, wherein 21 patients had tonsillar uptake, and 13 patients had base of tongue uptake. Tonsillar disease was mostly asymmetrical (n = 15/21), bilateral (n = 11/21), and had median SUVmax 9.35 (n = 12, IQR 7.4-11.15). Base of tongue was mostly asymmetrical (n = 7/13, 54%), bilateral (n = 8/13, 62%), and had median SUVmax 8.2 (n = 10, IQR 6.9-12.65). Seven patients had malignancy confirmed on tissue biopsy: five biopsies confirmed the tissue diagnosis of suspected lymphoma, and two incidental findings of unexpected malignancies: one p16 positive tonsillar squamous cell carcinoma, and one metastatic breast cancer.

CONCLUSION

In 31 patients undergoing tissue biopsy for incidental PET-avid oropharyngeal lesions, there were two unexpected malignancies. Our study results indicate that although unexpected malignancies are uncommon, a malignant diagnosis cannot be excluded from clinical features alone.

Staged neck dissection prior to transoral robotic surgery for oropharyngeal cancer: does it reduce post-operative complication rates? A multi-centre study of 104 patients

PURPOSE

Transoral robotic surgery (TORS) has become increasingly recognised as a safe and effective treatment for early oropharyngeal squamous cell carcinoma, often performed in conjunction with neck dissection (ND) and vessel ligation. It has been proposed that performing the neck dissection in a staged fashion prior to TORS results in low rates of transoral haemorrhage and pharyngocutaneous fistula, and may aid in TORS patient selection by eliminating patients who would require multi-modality treatment based on nodal pathology. This study aims to assess the effect of staged neck dissection with TORS in mitigating pharyngocutaneous fistulae and post-operative haemorrhage as well as the impact of staged ND on TORS patient selection.

METHODS

A retrospective cohort analysis was performed of patients undergoing staged ND with intent to proceed to TORS at two Australian hospitals between 2014 and 2022. Incidence of post-operative haemorrhage and pharyngocutaneous fistula and length of inpatient stay was identified. The number of patients who did not proceed to TORS was recorded.

RESULTS

One hundred and four patients were identified who underwent staged neck dissection with an intention to proceed to TORS. Six patients did not proceed to TORS following pathological assessment of the neck dissection specimen and ninety-eight patients (91 primary, 7 salvage) underwent TORS. There were six cases of secondary haemorrhage (one major, two intermediate and three minor). There were no cases of pharyngocutaneous fistula.

CONCLUSION

Staged neck dissection prior to TORS results in low rates of haemorrhage and pharyngocutaneous fistula and can improve TORS patient selection.

Transoral approach to accessory parotid tumours: case series and literature review

Accessory parotid tumours are rare, accounting for less than 10% of parotid neoplasms. Although similar tumours affect both the accessory parotid and parotid, accessory parotid tumours are associated with higher rates of malignancy. Surgery is first line management. Standard surgical management involves a similar approach to superficial parotidectomy, despite the anterior location of these lesions. This approach requires extensive subcutaneous access and facial nerve dissection and therefore, poses significant risk. It can also result in poor cosmetic result due to scarring and Frey's Syndrome. On the contrary, a transoral approach to reduces the risk of cosmetic deformity, reduces recovery time and does not increase risk to the facial nerve. We present a case series of patients with accessory parotid masses, which have been successfully excised transoral and without endoscopic assistance.

Predictors of distress associated with altered appearance and function in people treated surgically for oral cancers: a cross-sectional study

This cross-sectional study was performed to examine sources of variation in distress associated with altered appearance and fundamental functions in oral cancer patients at 2 months, 12-15 months, 24-36 months, and ≥ 5 years post-definitive treatment. Eligible patients completed six scales from the FACE-Q Head and Neck Cancer Module. Pre-specified regression models were used to examine sources of variation in study outcomes for 145 patients. Patient self-reports indicated that distress associated with altered appearance and fundamental functions was highly variable, and distress was present beyond 5 years post-definitive treatment in some patients. Associations between distress scores and time post-definitive treatment, reconstructive surgery, and adjuvant therapy were not statistically significant. There was, however, moderate to strong evidence against the null hypothesis of no association between eating distress scores and sex, primary cancer site, and T-stage; smiling distress scores and age and primary cancer site; appearance distress scores and geographical remoteness and primary cancer site; and speaking distress scores and primary cancer site. Primary cancer site was the only significant independent predictor of multiple distress scores. These findings suggest that predicting the psychological impact of oral cancer treatment remains a challenge for the multidisciplinary team. Screening and interventions for psychological distress are essential beyond the preoperative and acute care settings.

Surgical outcomes and longitudinal quality of life after endoscopic endonasal surgery for anterior skull base meningioma

OBJECTIVE

The objective of this study was to establish the effect of endoscopic endonasal surgery on longitudinal quality of life (QOL) in patients with anterior skull base meningioma.

METHODS

A prospectively collected cohort of consecutively operated anterior skull base meningiomas was analyzed. All cases were performed using the endoscopic endonasal approach (EEA). Sinonasal-specific and overall QOL were measured using the 22-Item Sinonasal Outcome Test and the Anterior Skull Base Questionnaire longitudinally (at 3 weeks, 6 weeks, and 3, 6, and 12 months) across the first postoperative year. The relationship between surgical and QOL outcomes to clinical and radiological characteristics was analyzed using multivariate regression.

RESULTS

Fifty cases were available, with a mean age of 61.5 years and female predominance (74.0%). Visual dysfunction and headache were the most common presenting symptoms, and tumors commonly took origin from the planum (46.0%), tuberculum (44.0%), and olfactory groove (24.0%). Median tumor volume was 4.6 cm3. Visual improvement was noted in 73.1% of cases with preoperative field deficits, while nonimprovement was associated with greater tumor height (p = 0.04). Gross-total resection was not possible in patients with 360° vessel encasement and high-grade cavernous sinus extension with ophthalmoplegia. Postoperative diabetes insipidus was observed only in cases with suprasellar extension. Sinonasal-specific QOL worsened transiently after surgery but returned to baseline levels after 3 weeks. Olfaction and taste scores returned to preoperative baseline scores within the year. Overall QOL at presentation was worse in those with larger tumors (p = 0.04) and visual failure (p = 0.04) and better in those presenting with headache (p = 0.04). Transient worsening of QOL was seen in the first 3 weeks, which returned to baseline by 6 weeks, and then improved to above preoperative levels at 6 months and beyond. Worse QOL at baseline (p = 0.01) and visual improvement (p = 0.01) predicted QOL improvement after surgery.

CONCLUSIONS

Longitudinal QOL in anterior skull base meningioma has been examined for the first time. Endoscopic endonasal surgery improves overall QOL after a transient 3-week worsening due to the sinonasal morbidity of the approach. Visual function is intimately tied to QOL, with worse vision associated with worse preoperative QOL, and QOL improving in parallel with visual restoration after surgery. The EEA is associated with better visual outcomes and should be the preferred approach in accessible tumors.

The effects of cerebrospinal fluid (CSF) diversion on post-operative CSF leak following extended endoscopic anterior skull base surgery

There is a paucity of high quality evidence regarding the routine placement of lumbar drain (LD) in reducing post-operative (op) cerebrospinal fluid (CSF) leak after extended endoscopic trans-sphenoidal resection of anterior skull base lesions. In this study, we sought to compare the incidence of post-op CSF leak between patients with upfront LD insertion and those without it. This was a prospective randomized controlled trial conducted over a period of 5 years with patients undergoing extended endoscopic trans-sphenoidal surgery randomly assigned to either LD insertion at the time of surgery, or no LD placement. Thirty-eight patients with anterior skull base tumors were accrued from three tertiary hospitals of Melbourne. Post-op leak was confirmed by β2-transferrin-positive rhinorrhea, and/or worsening pneumocephalus on brain imaging. Skull base defect size and pedicled nasoseptal flap viability were assessed on post-op CT and MRI, respectively. There was no significant difference in post-op CSF leak incidence between the two subgroups (12.50% in LD arm vs. 9.10% in no LD arm). Patients with LD insertion however, demonstrated substantially raised complication rates, longer hospital lengths of stay and lower subjective quality of life measures at 12 months compared with those without LD. In conclusion, routine placement of LD at the time of surgery for extended anterior skull base trans-nasal approach did not reduce the risk of post-op CSF leak. Discretion is warranted when using LD as an adjunct due to its associated morbidities, prolonged hospital stay and adverse effect on patients' subjective outcome measures.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium

BACKGROUND

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies.

PATIENTS AND METHODS

Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients).

RESULTS

A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality.

CONCLUSIONS

Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies.

CLINICAL TRIAL IDENTIFIER

NCT04354701.

0330 Sleep Hygiene in Preschoolers: Assessing Biopsychosocial Factors Associated with Preschoolers’ Readiness to Learn

Introduction

Sleep is crucial during early development to promote health, education, growth, and quality of life. Insufficient sleep is a public health problem, and this is clearly true for young children. The National Institutes of Health reported that preschoolers need 11-12 hours of sleep daily. We hypothesized that more physically active children would experience better sleep quality which would be associated with higher scores on cognitive and socioemotional measures. We also hypothesized that increased parental awareness of their child’s sleep patterns would predict more successful sleep health indicators in their children, leading to positive impact on preschoolers’ readiness to learn.

Methods

82 preschoolers (ages 3-5) completed memory tests, a sleep hygiene scale, and a socioemotional assessment. Following initial cognitive and socioemotional testing, Fitbit devices collected activity and sleep measures for 12 weeks. Additionally, parents recorded bedtimes, wake times, total sleep time, naps, and activity levels in daily sleep journals. We assessed the association between physical activity and sleep quality, bedtime, wake time, memory, sleep hygiene, and socioemotional measures.

Results

Physical activity was positively associated with better sleep habits, including earlier bedtimes, earlier wake times, more consistent sleep-wake patterns, socioemotional scores, and working memory capacity. Higher child and parent sleep hygiene scales were associated with more consistent bedtimes. On average, the 82 preschoolers tested fell short of the recommended 11-12 hours of sleep per night.

Conclusion

Greater child and parent awareness of practicing good sleep hygiene increased the likelihood for the child to practice better sleep habits. Since physical activity was positively associated with sleep health measures, it is critical that parents and teachers prioritize sleep and activity in young children. Results of this study provide greater knowledge regarding associations between sleep, physical activity, and biopsychosocial outcomes that may be useful in implementing better education for parents and children geared toward improving sleep.

Support

This research was generously supported by the Caplan Foundation for Early Childhood and the Hope College Psychology Department.

Extracellular dsRNA induces a type I interferon response mediated via class A scavenger receptors in a novel Chinook salmon derived spleen cell line

Despite increased global interest in Chinook salmon aquaculture, little is known of their viral immune defenses. This study describes the establishment and characterization of a continuous cell line derived from Chinook salmon spleen, CHSS, and its use in innate immune studies. Optimal growth was seen at 14-18 °C when grown in Leibovitz's L-15 media with 20% fetal bovine serum. DNA analyses confirmed that CHSS was Chinook salmon and genetically different from the only other available Chinook salmon cell line, CHSE-214. Unlike CHSE-214, CHSS could bind extracellular dsRNA, resulting in the rapid and robust expression of antiviral genes. Receptor/ligand blocking assays confirmed that class A scavenger receptors (SR-A) facilitated dsRNA binding and subsequent gene expression. Although both cell lines expressed three SR-A genes: SCARA3, SCARA4, and SCARA5, only CHSS appeared to have functional cell-surface SR-As for dsRNA. Collectively, CHSS is an excellent cell model to study dsRNA-mediated innate immunity in Chinook salmon.

Development and use of an Arctic charr cell line to study antiviral responses at extremely low temperatures

Arctic charr (Salvelinus alpinus) are the northernmost distributed freshwater fish and can grow at water temperatures as low as 0.2 °C. Other teleost species have impaired immune function at temperatures that Arctic charr thrive in, and thus, charr may maintain immune function at these temperatures. In this study, a fibroblastic cell line, named ACBA, derived from the bulbus arteriosus (BA) of Arctic charr was developed for use in immune studies at various temperatures. ACBA has undergone more than forty passages at 18 °C over 3 years, while showing no signs of senescence-associated β-galactosidase activity and producing nitric oxide. Remarkably, ACBA cells survived and maintained some mitotic activity even at 1 °C for over 3 months. At these low temperatures, ACBA also continued to produce MH class I proteins. After challenge with poly I:C, only antiviral Mx proteins were induced while MH proteins remained constant. When exposed to live viruses, ACBA was shown to permit viral infection and replication of IPNV, VHSV IVa and CSV at 14 °C. Yet at the preferred temperature of 4 °C, only VHSV IVa was shown to replicate within ACBA. This study provides evidence that Arctic charr cells can maintain immune function while also resisting infection with intracellular pathogens at low temperatures.

Temporary protection of rainbow trout gill epithelial cells from infection with viral haemorrhagic septicaemia virus IVb

The branchial epithelium is not only a primary route of entry for viral pathogens, but is also a site of viral replication and subsequent shedding may also occur from the gill epithelium. This study investigated the potential of agents known to stimulate innate immunity to protect rainbow trout epithelial cells (RTgill-W1) from infection with VHSV IVb. RTgill-W1 cells were pretreated with poly I:C, FuGENE(®) HD + poly I:C, lipopolysaccharide (LPS), LPS + poly I:C or heat-killed VHSV IVb and then infected with VHSV IVb 4 days later. Cytopathic effect (CPE) was determined at 2, 3, 4, 7 and 11 days post-infection. Virus in cells and supernatant was detected using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). All of the treatments delayed the onset of CPE (per cent of monolayer destruction), compared with untreated controls; however, killed VHSV or poly I:C combined with LPS was the most effective. Similarly, the detection of viral RNA in the supernatant was delayed, and the quantity was significantly (P < 0.05) reduced by all treatments with the exception of LPS alone (4 days). Unlike many of the other treatments, pretreatment of RTgill-W1 with heat-killed VHSV did not upregulate interferon 1, 2 or MX 1 gene expression.

A trial of nebulised heparin to limit lung injury following cardiac surgery

Cardiac surgery with cardiopulmonary bypass triggers an acute inflammatory response in the lungs. This response gives rise to fibrin deposition in the microvasculature and alveoli of the lungs. Fibrin deposition in the microvasculature increases alveolar dead space, while fibrin deposition in alveoli causes shunting. We investigated whether prophylactic nebulised heparin could limit this form of lung injury. We undertook a single-centre double-blind randomised trial. Forty patients undergoing elective cardiac surgery with cardiopulmonary bypass were randomised to prophylactic nebulised heparin (50,000 U) or placebo. The primary endpoint was the change in arterial oxygen levels over the operative period. Secondary endpoints included end-tidal CO₂, the alveolar dead space fraction and bleeding complications. We found nebulised heparin did not improve arterial oxygen levels. Nebulised heparin was, however, associated with a lower alveolar dead space fraction (P <0.05) and lower tidal volumes at the end of surgery (P <0.01). Nebulised heparin was not associated with bleeding complications. In conclusion, prophylactic nebulised heparin did not improve oxygenation, but was associated with evidence of better alveolar perfusion and CO₂elimination at the end of surgery.

Differential viral haemorrhagic septicaemia virus genotype IVb infection in fin fibroblast and epithelial cell lines from walleye, Sander vitreus (Mitchill), at cold temperatures

A cell line, WE-cfin11e, with an epithelial-like morphology was developed from a caudal fin of walleye, Sander vitreus (Mitchill), characterized as distinct from the established walleye caudal fin fibroblast-like cell line, WE-cfin11f, and compared with WE-cfin11f for susceptibility to VHSV IVb. Immunocytochemistry and confocal microscopy were used to localize the intermediate filament protein, vimentin, the tight junction protein, zonula occludens-1 (ZO-1), the extracellular matrix protein, collagen I, and the viral protein, G. Although both cell lines contained vimentin, only WE-cfin11e stained for ZO-1 and only WE-cfin11f stained for collagen I. Ascorbic acid increased the accumulation of collagen I and caused the appearance of collagen fibres only in WE-cfin11f cultures. At 14 °C, both cell lines produced VHSV IVb, but the infection developed more rapidly in WE-cfin11f. At 4 °C, both cell lines became infected with VHSV IVb as judged by the expression of viral proteins, N and G, but only WE-cfin11f produced virus. The results suggest that cold temperatures can modulate viral tropism.

Walleye Sander vitreus (Mitchill) are relatively resistant to experimental infection with VHSV IVb and extant walleye strains vary in susceptibility

Compared to fathead minnow, walleye demonstrate low susceptibility to experimental infection with VHSV IVb, regardless of route of exposure or water temperature at time of infection. In triplicate and duplicate groups, walleye were intraperitoneally (i.p.) injected (10² -10⁸  pfu/fish) or waterborne-exposed (w; 1.4 × 10⁷  pfu mL^-1 ) with VHSV IVb. High cumulative mortality (64-100%) and severe gross lesions associated with VHSV IVb infection were evident only in fish i.p. injected with 10⁸  pfu at 12 °C. These fish had multifocal necrosis of several tissues including the gill and heart. There was no difference in mortality between walleye infected (w or i.p.) at 12 °C (spring stocking) compared with a declining temperature profile from 18 to 12 °C (fall stocking). There were significant differences (P < 0.05) in mortality between four extant walleye strains following i.p. infection, indicating that the choice of walleye strain for stocking might be an important consideration. Viral antigen was found in both i.p. and w-exposed walleye using immunohistochemistry, mostly within the gill and skin of w-exposed fish and most prominently in dermal fibrocytes. VHSV IVb was detected in multiple tissues from 6 to 21 days post-infection using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR).

Development of a walleye cell line and use to study the effects of temperature on infection by viral haemorrhagic septicaemia virus group IVb

A cell line, WE-cfin11f, with a fibroblast-like morphology was developed from a walleye caudal fin and used to study the intersection of thermobiology of walleye, Sander vitreus (Mitchill), with the thermal requirements for replication of viral haemorrhagic septicaemia virus (VHSV) IVb. WE-cfin11f proliferated from 10 to 32 °C and endured as a monolayer for at least a week at 1-34 °C. WE-cfin11f adopted an epithelial shape and did not proliferate at 4 °C. Adding VHSV IVb to cultures at 4 and 14 °C but not 26 °C led to cytopathic effects (CPE) and virus production. At 4 °C, virus production developed more slowly, but Western blotting showed more N protein accumulation. Infecting monolayer cultures at 4 °C for 7 days and then shifting them to 26 °C resulted in the monolayers being broken in small areas by CPE, but with time at 26 °C, the monolayers were restored. These results suggest that at 26 °C, the VHSV IVb life cycle stages responsible for CPE can be completed, but the production of virus and the initiation of infections cannot be accomplished.

Molecular characterization of three novel chemokine receptors in rainbow trout (Oncorhynchus mykiss)

Chemokines signal through a family of seven-transmembrane domain G-coupled receptors in order to regulate both leukocyte mobilization and activate the recruited cells. Although many chemokines have been identified in rainbow trout (Oncorhynchus mykiss), only a few chemokine receptors have been reported to date. In this work, we have cloned three novel chemokine receptors in rainbow trout. One of these receptors seems to be a clear orthologue of CCR6, while the second one constitutes a novel CCR9 gene different from the previous CCR9 reported in this species. This gene, which we have designated as CCR9B, represents another lineage of fish CCR9 genes, not previously identified. Finally, a deeper phylogenetic analysis of the third novel chemokine receptor gene, which had been identified on the basis of sequence similarity to CCR3, constitutes a novel lineage of CCR receptors which has no equivalent in humans and that may be teleost-specific. We have designated this novel gene as CCR13, to avoid any possible ascription to mammalian genes. Further transcriptional studies revealed that CCR6 was constitutively transcribed in thymus, gills, hindgut and peripheral blood leukocytes (PBLs), while CCR9B was strongly transcribed in thymus and PBLs but also in spleen, gills, hindgut and brain at lower levels. CCR13, on the other hand, was strongly detected in spleen, head kidney and PBLs and faintly in thymus, gills, brain and gonad. The data provided constitutes a step forward the identification of novel chemokine receptors that may contribute to a future understanding of chemokine signalling in fish.

Differential effects of viral hemorrhagic septicaemia virus (VHSV) genotypes IVa and IVb on gill epithelial and spleen macrophage cell lines from rainbow trout (Oncorhynchus mykiss)

The two most prominent genotypes of viral hemorrhagic septicemia virus (VHSV) are -I in the Northeastern Atlantic region and -IV in North America, but much more is known about the cellular pathogenesis of genotype -I than -IV. VHSV genotype -IV is divided into -IVa from the Northeast Pacific Ocean and -IVb from the Great Lakes and both of which are less virulent to rainbow trout than genotype -I. In this work, infections of VHSV-IVa and -IVb have been studied in two rainbow trout cell lines, RTgill-W1 from the gill epithelium, and RTS11 from spleen macrophages. RTgill-W1 produced infectious progeny of both VHSV-IVa and -IVb. However, VHSV-IVa was more infectious than -IVb toward RTgill-W1: -IVa caused cytopathic effect (CPE) at a lower viral titre, elicited CPE earlier, and yielded higher titres. By contrast, no CPE and no increase in viral titre were observed in RTS11 cultures infected with either genotype. Yet in RTS11 all six VHSV genes were expressed and antiviral genes, Mx2 and Mx3, were up regulated by VHSV-IVb and -IVa. However, replication appeared to terminate at the translational stage as viral N protein, presumably the most abundant of the VSHV proteins, was not detected in either infected RTS11 cultures. In RTgill-W1, Mx2 and Mx3 were up regulated to similar levels by both viral genotypes, while VHSV-IVa induced higher levels of IFN1, IFN2 and LGP2A than VHSV-IVb.

Modulation of the response of a rodent fibrosarcoma to photodynamic therapy by hyperbaric-oxygen treatment

The ability of hyperbaric oxygen (HBO) treatment to modulate the response of a rodent fibrosarcoma to interstitial photodynamic therapy (PDT) using 630 nm light and intravenous polyhaematoporphyrin (PHP) was examined. Application of HBO for 30 min immediately prior to PDT resulted in a light dose-dependent increase in tumour growth retardation, maximum effect (+227%) being observed with 100J light, and no enhancement being seen at or above 400J. Application of HBO during or immediately after PDT had no effect on response. Reducing the interval between giving PHP and administering light from the usual 48 h to just 1 h increased the efficacy of PDT even in the absence of HBO pre-treatment. Under these circumstances, application of HBO did not realise any further increase in tumour response at any light dose. Our findings suggest that manipulation of tumour oxygenation may be able to improve the outcome of PDT under some circumstances, but that careful consideration of other treatment variables, such as light dose and drug-to-light interval, may provide similar, more easily achievable, improvements in efficacy.

Global major histocompatibility class II β (mh-IIβ)-polymorphism in Arctic charr Salvelinus alpinus

This study explored the use of the gene encoding the β subunit of the major histocompatibility (MH) receptor as a population marker in Arctic charr Salvelinus alpinus. The use of this polymorphic marker allowed differentiation of the S. alpinus lineages previously defined using mitochondrial DNA (mtDNA) but also allowed differentiation between the populations studied within those lineages. The majority of the variation observed here occurred prior to the last glaciation event. Nevertheless, all S. alpinus populations were differentiated using both MH Class II β (mh-IIβ) sequences and allelic frequencies. The fact that all the populations studied presented high rates of non-synonymous: synonymous substitutions and high levels of interpopulation variation, suggested mh-IIβ as an ideal marker to assess differentiation among S. alpinus populations in ways that may represent divergence both by genetic drift and natural adaptation to the local environment.

Determination of emitted airborne microorganisms from a BIO-PAK wastewater treatment plant

Results of a study conducted to assess the degree of airborne microbial contamination generated by a wastewater treatment plant (WWTP) with bioreactor "BIO-PAK" closed treatment system and evaluation of the dispersion of potential pathogens are described. Over the year aerosol samples were collected simultaneously with sedimentation and impact methods from several plant sites and the surroundings. External upwind sites were used as control. Total colony-forming counts of heterotrophic psychrophilic, psychrotrophic, mesophilic, haemolytic bacteria, as well as members of the Enterobacteriaceae family, Staphylococcus, Enterococcus and Pseudomonas genera, actinomycetes and fungi (moulds, yeasts and yeast-like fungi) were determined. Their highest concentrations ranged up to 10(1)-10(3)CFU/m(3) (with the exception of moulds exceeding 2x10(4)) were determined in air sampled inside the bioreactor, its vicinity, and near the grate chamber. Higher species diversity of the family Enterobacteriaceae (including Shigella spp., Yersinia enterocolitica, Escherichia coli, Klebsiella pneumoniae ozaenae) in the air sampled inside or near the bioreactor may imply a health risk for staff exposed for longer periods of time. Notwithstanding, no increased emission of the analysed groups of microorganisms, including faecal bacteria, were found outside the WWTP.

Effect of 17beta-hydroxysteroid dehydrogenase type 2 inhibitor on bone strength in ovariectomized cynomolgus monkeys

In both sexes, a reduction in sex steroid production with aging impairs the musculoskeletal system. The goal of our study was to test the ability of WH-9062, a novel non-steroidal small molecule inhibitor of the 17beta-Hydroxysteroid Dehydrogenase type 2 enzyme, to maintain or improve bone strength without raising serum levels of testosterone or estradiol. Mature, female cynomolgus monkeys with sealed growth plates were allocated into six groups: Sham controls, OVX controls, OVX+Premarin (15 mg/kg/d), and three groups of OVX monkeys receiving WH-9062 at 1, 5 and 25 mg/kg/day. All treatments were administered by daily oral dosing for 23 weeks. Changes in lipid profile caused by OVX were corrected with WH-9062 and included lowering total of cholesterol and non-HDL cholesterol, and maintenance of initial plasma levels of HDL cholesterol. Only the highest dose of WH-9062 lowered bone resorption relative to OVX controls. Elevated bone specific alkaline phosphatase, osteocalcin, BMC and dynamic bone histomorphometry data resulted in desirable bone balance and bone strength. The obtained results support our theory that inhibition of 17beta-HSD type 2 resulted in high local estrogen and/or testosterone levels leading to maintenance of bone formation and bone strength. Collectively, our data demonstrated that the treatment paradigm that utilizes tissue selectivity and receptor bioavailability in conversion of inactive hormones to active forms could be achieved and could result in desirable effects on target tissues such as bone and muscles.

The immune and stress responses of Atlantic cod to long-term increases in water temperature

Sea-caged cod are limited in their movements in the water column, and thus can be exposed to large seasonal ( approximately 0-20 degrees C) temperature fluctuations. To investigate the physiological response of Atlantic cod to summer-like increases in temperature, we exposed 10 degrees C acclimated juvenile cod to a graded thermal challenge (1 degrees C increase every 5 days) and measured: (1) plasma cortisol and glucose levels; (2) the respiratory burst activity of blood leukocytes; and (3) the expression of specific immune-related genes [MHC Class I, Interleukin-1beta (IL-1beta), beta2-microglobulin (beta2-M), Immunoglobulin M (IgM)-light (L) and -heavy (H) chains] in the blood using quantitative reverse transcription-polymerase chain reaction (QRT-PCR). The experiment was stopped at 19.1 degrees C, with 26.7% of the fish surviving to this point. Plasma glucose levels increased slightly at 16 and 18 degrees C (by 1.39- and 1.74-fold, respectively), in contrast, cortisol levels were elevated significantly (by 2.9-fold) at 16 degrees C but returned to control levels thereafter. The effect of increasing temperature on the expression of immune related genes in blood cells (leukocytes) was variable and depended on the gene of interest. The expression of IgM-H remained stable for the duration of the experiment. In contrast, IL-1beta expression was increased significantly (by approximately 25-fold) at 19 degrees C as compared to time-matched control fish, and changes in the expression of beta2-M, MHC Class I and IgM-L followed a pattern similar to that seen for cortisol: increasing at 16 degrees C (by 4.2-, 5.3- and 17-fold, respectively), but returning to pre-stress levels by 19 degrees C. Interestingly, increasing temperatures had no effect on respiratory burst activity. This study is the first to examine the effects of a chronic regimen of increasing temperature on the stress physiology and immunology of a marine teleost, and suggests that immune function is influenced by complex interactions between thermal effects and temperature-induced stress (elevated circulating cortisol levels).

Sex change strategy and the aromatase genes

Sequential hermaphroditism is a common reproductive strategy in many teleosts. Steroid production is known to mediate both the natural and induced sex change, yet beyond this the physiology directing this process has received little attention. Cytochrome P450 aromatase is a key enzyme in the hormonal pathway catalysing the conversion of sex steroids, androgens to oestrogens, and thus is highly relevant to the process of sex change. This study reports the isolation of cDNA sequences for aromatase isoforms CYP19A1 and CYP19A2 from teleost species representing three forms of sexual hermaphroditism: Lates calcarifer (protandry), Cromileptes altivelis (protogyny), and Gobiodon histrio (bi-directional). Deduced amino acid analysis of these isoforms with other reported isoforms from gonochoristic (single sex) teleosts revealed 56-95% identity within the same isoform while only 48-65% identity between isoforms irrespective of species and sexual strategy. Phylogenetic analysis supported this result separating sequences into isoform exclusive clades in spite of species apparent evolutionary distance. Furthermore, this study isolates 5' flanking regions of all above genes and describes putative cis-acting elements therein. Elements identified include steroidogenic factor 1 binding site (SF-1), oestrogen response element (ERE), progesterone response element (PRE), androgen response element (ARE), glucocorticoid response elements (GRE), peroxisome proliferator-activated receptor alpha/retinoid X receptor alpha heterodimer responsive element (PPARalpha/RXRalpha), nuclear factor kappabeta (NF-kappabeta), SOX 5, SOX 9, and Wilms tumor suppressor (WTI). A hypothetical in vivo model was constructed for both isoforms highlighting potential roles of these putative cis-acting elements with reference to normal function and sexual hermaphroditism.

Outbreak of cyclosporiasis in British Columbia associated with imported Thai basil

Sporadic outbreaks of cyclosporiasis, a common cause of protracted diarrhoea in underdeveloped countries, are often undetected and undiagnosed in industrial countries. In May 2001, an outbreak of Cyclospora cayetanensis gastroenteritis was identified in British Columbia, Canada, with 17 reported cases. We conducted a case-control study involving 12 out of the 17 reported and confirmed case patients. Eleven (92%) of the patients had consumed Thai basil, an essential ingredient in Vietnamese cuisine, compared to 3 out of 16 (19%) of the control patients (P = 0.003). Trace-back investigations implicated Thai basil imported via the United States as the vehicle for this outbreak. This is the first documented sporadic outbreak of cyclosporiasis linked to Thai basil in Canada, and the first outbreak of cyclosporiasis identified in an ethnic immigrant population. This outbreak provides the opportunity to increase our understanding of this emerging pathogen and improve on our prevention and control for future outbreaks.

The role of microvascular thrombosis in sepsis

The acute inflammatory response to sepsis gives rise to significant morbidity and mortality. The mechanisms underlying this form of tissue injury are poorly understood. This review examines the evidence that tissue ischaemia due, to generalized microvascular thrombosis may play an important role. Microvascular thrombosis is probably an adaptive response that prevents bacteria in the tissues reaching the systemic circulation via the capillaries. In time, a definitive response by leucocytes removes the bacteria and repairs the damaged tissues. There is however evidence that if microvascular thrombosis becomes generalized, then extensive tissue ischaemia may precipitate organ failure and death. Post-mortem studies of patients with sepsis demonstrate microvascular thrombi in many organs including the kidney, liver, lung, gut, adrenals and brain, and the degree of organ injury is related to the quantity of thrombi. Furthermore studies in human and animal models of sepsis demonstrate therapies that inhibit coagulation or promote fibrinolysis reduce organ failure and mortality. In view of the personal and economic burdens that tissue injury associated with the acute inflammatory response places on the community, further studies to establish the role of microvascular thrombosis are clearly required. Such studies may lead to new therapies to limit or prevent this form of injury.

Conversation starters: re-examining and reconstructing first encounters within the therapeutic relationship

This paper describes, analyses and reconstructs early encounters between nurse and client. Too often nurses take for granted ordinary encounters with clients and thus overlook opportunities to develop the nurse-client relationship. Common encounters, drawn from reflection on practice, are analysed using contemporary cultural theories. Creative alternatives are suggested and we argue that they represent opportunities to make meaningful connections with and for clients. As conversation starters, these ideas may be used by nurses to facilitate a more trusting therapeutic relationship. They may help to deepen understanding or insight into mental health problems and help to reveal hidden strengths and solutions. By noticing, valuing, discussing and developing this space, we as mental health nurses are extending our discipline base and articulating, with more precision and persuasion, exactly how we contribute to better health outcomes.

Cloning and characterization of cDNA clones encoding membrane-bound and potentially secreted major histocompatibility class I receptors from walleye (Stizostedion vitreum)

Major histocompatibility (MH) gene polymorphism has been used to type populations of humans, mice, and fish. Walleye ( Stizostedion vitreum) comprise an economically important fishery in Lake Erie, but whether those in the western basin form a single population or separate shoal- and river-breeding populations is not known. To develop MH gene markers for use in defining their population structure, we constructed a head kidney cDNA library from which five full-length class I heavy-chain clones were isolated and sequenced. Although they came in roughly three sizes, 1300, 1400, and over 2000 bp, the clones all exhibited a high degree of sequence similarity to each other and to known teleost MH class I cDNAs in the area encoding the extracellular domains, but showed dramatic differences in their transmembrane and cytoplasmic domains. One clone had an AG repeat that eliminated the hydrophobicity of the transmembrane domain, indicating that it may encode a secreted class I receptor. The other four clones encode three distinctly different cytoplasmic domains. The two clones that encode the same cytoplasmic domain resemble those of the known teleost MH class I sequences the most. Southern blotting indicated that there were four copies of the gene present in the walleye genome. Northern blotting showed that class I MH genes are expressed in most tissues and mRNAs of all three size classes can be detected. A preliminary survey of the polymorphism of these genes indicates that they will provide useful markers for differentiating fish stocks.

The relationship between major histocompatibility receptors and innate immunity in teleost fish

Studies of the innate immune system have recently shown that, in addition to its role in producing the primary response that slows down pathogens, it may also play an important role in initiating and directing the type of response that the adaptive immune system makes. These discoveries have shown a complex web of control containing new roles for the innate immune system in organizing responses of T-cell to antigens being presented by major histocompatibility receptors, as well as new roles for those receptors in innate immune responses. Both of these activities are managed through feedback networks involving elements of both the innate and adaptive immune system. This paper will discuss these newly discovered interactions and how they are influencing current theories regarding the initiation of adaptive immune responses. In particular, it will highlight the recent progress that is being made towards understanding these relationships in the immune systems of teleost fish.

Activation of the kallikrein-kinin system by cardiopulmonary bypass in humans

We used cardiopulmonary bypass (CPB) as a model of activation of the contact system and investigated the involvement of the plasma and tissue kallikrein-kinin systems (KKS) in this process. Circulating levels of bradykinin and kallidin and their metabolites, plasma and tissue kallikrein, low and high molecular weight kininogen, and kallistatin were measured before, during, and 1, 4, and 10 h after CPB in subjects undergoing cardiac surgery. Bradykinin peptide levels increased 10- to 20-fold during the first 10 min, returned toward basal levels by 70 min of CPB, and remained 1.2- to 2.5-fold elevated after CPB. Kallidin peptide levels showed little change during CPB, but they were elevated 1.7- to 5.2-fold after CPB. There were reductions of 80 and 60% in plasma and tissue kallikrein levels, respectively, during the first minute of CPB. Kininogen and kallistatin levels were unchanged. Angiotensin-converting enzyme inhibition did not amplify the increase in bradykinin levels during CPB. Aprotinin administration prevented activation of the KKS. The changes in circulating kinin and kallikrein levels indicate activation of both the plasma and tissue KKS during activation of the contact system by CPB.