Exploring recent patterns of migration of doctors to the United Kingdom: a mixed-methods study.

INTRODUCTION: A shortage of doctors is currently one of the biggest challenges faced by the healthcare workforce in the United Kingdom (UK). While plans are in place to increase the number of medical school places, in the short-term this gap will need to continue to be filled by the international recruitment of doctors. The aim of this study is to identify key factors that explain the patterns of migration of doctors to the UK, in order to aid the development of policies to recruit and retain a sustainable workforce. METHODS: We analysed General Medical Council (GMC) secondary data on the patterns of migration of internationally trained doctors (2009-2019). Qualitative interviews were conducted with 17 stakeholders by videoconferencing which were audio-recorded, transcribed and thematically analysed using NVivo. RESULTS: In 2019, 34.5% of UK doctors were trained internationally mainly in India, Pakistan, Italy, Nigeria, Greece, Romania and Egypt. Most new registrations by internationally trained doctors from 2009-2019 did not have a specialty at the time of initial registration (96.2% in 2019). Only a relatively small number of these doctors go on to gain specialist or GP registration (11.6% within 5 years and 27.2% within 10 years of registration). The stakeholder interviews highlighted training opportunities and career progression as the main drivers of migration. The barriers internationally trained doctors face regarding specialty training included differences between UK and destination health systems, systematic bias, bureaucracy and selection processes not being accessible. CONCLUSION: This study makes a contribution to the literature by identifying recent patterns in the migration of doctors to the UK. The UK's dependence on internationally trained doctors has important global implications as source countries are losing skilled health workers which is undermining their health systems. In keeping with the WHO Global Code on the International Recruitment of Healthcare Personnel, policymakers need to consider how to reduce the UK's reliance on internationally trained doctors, particularly from countries on the safeguard list whilst continuing the drive to increase medical school places. Additional support is required for internationally trained doctors, to ensure that they get on the training programmes they seek, enabling their career progression.

Drivers and barriers of international migration of doctors to and from the United Kingdom: a scoping review.

BACKGROUND: Many high-income countries are heavily dependent on internationally trained doctors to staff their healthcare workforce. Over one-third of doctors practising in the UK received their primary medical qualification abroad. Simultaneously, an average of around 2.1% of doctors leave the UK medical workforce annually to go overseas. The aim of this study was to identify the drivers and barriers of international migration of doctors to and from the UK. METHODS: A scoping review was conducted. We searched EMBASE, MEDLINE, CINAHL, ERIC and BEI in January 2020 (updated October 2021). Grey literature and citation searching were also carried out. Empirical studies reporting on the drivers and barriers to the international migration of doctors to and from the UK published in the English language from 2009 to present were included. The drivers and barriers were coded in NVivo 12 building on an existing framework. RESULTS: 40 studies were included. 62% were quantitative, 18% were qualitative, 15% were mixed-methods and 5% were literature reviews. Migration into and out of the UK is determined by a variety of macro- (global and national factors), meso- (profession led factors) and micro-level (personal factors). Interestingly, many of the key drivers of migration to the UK were also factors driving migration from the UK, including: poor working conditions, employment opportunities, better training and development opportunities, better quality of life, desire for a life change and financial reasons. The barriers included stricter immigration policies, the registration process and short-term job contracts. CONCLUSIONS: Our research contributes to the literature by providing a comprehensive up-to-date review of the drivers and barriers of migration to and from the UK. The decision for a doctor to migrate is multi-layered and is a complex balance between push/pull at macro-/meso-/micro-levels. To sustain the UK's supply of overseas doctors, it is vital that migration policies take account of the drivers of migration particularly working conditions and active recruitment while addressing any potential barriers. Immigration policies to address the impact of Brexit and the COVID-19 pandemic on the migration of doctors to and from the UK will be particularly important in the immediate future. Trial registration PROSPERO CRD42020165748.

Rehearsal's effect on recall and comprehension of orthodontic informed consent.

INTRODUCTION: Proper informed consent allows patients to take an active role in their own treatment decisions, and enhanced compliance might improve treatment outcomes. The objective of this research was to determine if handwritten rehearsal of core and custom consent items would increase short-term recall and comprehension. METHODS: A total of 90 patient-parent pairs were randomly assigned to 2 groups. After case presentation, each subject was provided 10 minutes to read a modified informed consent document. Group A received visual printouts containing the 4 core elements (root resorption, decalcification, pain, and relapse/retention) likely to be encountered by all patients and up to 4 custom elements (eg, impacted teeth, orthognathic surgery, or other case-specific treatment issues). Subjects identified and wrote what the image depicted and how it could affect treatment. Group B viewed a slideshow presentation on all 18 consent elements arranged from general to specific. All participants were interviewed, and each provided their sociodemographic data, as well as completed literacy, health literacy, and state anxiety questionnaires. The groups were compared for recall and comprehension through an analysis of covariance. RESULTS: The rehearsal intervention significantly improved recall and comprehension of the core elements (P = 0.001). Rehearsal also improved custom recall and comprehension, but not significantly. Group B performed significantly better on treatment questions (P = 0.001). Overall, as anxiety increased, correct responses decreased. CONCLUSIONS: The rehearsal group improved recall and comprehension of the core and custom elements of informed consent and proved a more efficient method than an audiovisual presentation to provide informed consent. It also improved meeting legal obligations.

Identification of the Corticobulbar Tracts of the Tongue and Face Using Deterministic and Probabilistic DTI Fiber Tracking in Patients with Brain Tumor.

BACKGROUND AND PURPOSE: The corticobulbar tract of the face and tongue, a critical white matter tract connecting the primary motor cortex and the pons, is rarely detected by deterministic DTI fiber tractography. Detection becomes even more difficult in the presence of a tumor. The purpose of this study was to compare identification of the corticobulbar tract by using deterministic and probabilistic tractography in patients with brain tumor. MATERIALS AND METHODS: Fifty patients with brain tumor who underwent DTI were studied. Deterministic tractography was performed by using the fiber assignment by continuous tractography algorithm. Probabilistic tractography was performed by using a Monte Carlo simulation method. ROIs were drawn of the face and tongue motor homunculi and the pons in both hemispheres. RESULTS: In all subjects, fiber assignment by continuous tractography was ineffectual in visualizing the entire course of the corticobulbar tract between the face and tongue motor cortices and the pons on either side. However, probabilistic tractography successfully visualized the corticobulbar tract from the face and tongue motor cortices in all patients on both sides. No significant difference (P < .08) was found between both sides in terms of the number of voxels or degree of connectivity. The fractional anisotropy of both the face and tongue was significantly lower on the tumor side (P < .03). When stratified by tumor type, primary-versus-metastatic tumors, no differences were observed between tracts in terms of the fractional anisotropy and connectivity values (P > .5). CONCLUSIONS: Probabilistic tractography successfully reconstructs the face- and tongue-associated corticobulbar tracts from the lateral primary motor cortex to the pons in both hemispheres.

Challenges in Identifying the Foot Motor Region in Patients with Brain Tumor on Routine MRI: Advantages of fMRI.

BACKGROUND AND PURPOSE: Accurate localization of the foot/leg motor homunculus is essential because iatrogenic damage can render a patient wheelchair- or bed-bound. We hypothesized the following: 1) Readers would identify the foot motor homunculus <100% of the time on routine MR imaging, 2) neuroradiologists would perform better than nonradiologists, and 3) those with fMRI experience would perform better than those without it. MATERIALS AND METHODS: Thirty-five attending-level raters (24 neuroradiologists, 11 nonradiologists) evaluated 14 brain tumors involving the frontoparietal convexity. Raters were asked to identify the location of the foot motor homunculus and determine whether the tumor involved the foot motor area and/or motor cortex by using anatomic MR imaging. Results were compared on the basis of prior fMRI experience and medical specialty by using Mann-Whitney U test statistics. RESULTS: No rater was 100% correct. Raters correctly identified whether the tumor was in the foot motor cortex 77% of the time. Raters with fMRI experience were significantly better than raters without experience at foot motor fMRI centroid predictions (13 ± 6 mm versus 20 ± 13 mm from the foot motor cortex center, P = 2 × 10(-6)) and arrow placement in the motor gyrus (67% versus 47%, P = 7 × 10(-5)). Neuroradiologists were significantly better than nonradiologists at foot motor fMRI centroid predictions (15 ± 8 mm versus 20 ± 14 mm, P = .005) and arrow placement in the motor gyrus (61% versus 46%, P = .008). CONCLUSIONS: The inability of experienced readers to consistently identify the location of the foot motor homunculus on routine MR imaging argues for using fMRI in the preoperative setting. Experience with fMRI leads to improved accuracy in identifying anatomic structures, even on routine MR imaging.

Acute corneal hydrops in keratoconus: a national prospective study of incidence and management.

PurposeTo determine incidence and management of acute corneal hydrops in the UK.MethodsWe used the BOSU report card system to survey cases of acute corneal hydrops in patients with keratoconus that occurred in the UK between November 2009 and December 2010. Ophthalmologists who reported a case were sent an initial questionnaire, with a follow-up questionnaire after 6 months. We collected information on the demographics, complications, changes in visual acuity, and management. The 2011 National Census was used as a source for population and ethnicity in the UK.ResultsThere were 73 incident cases of acute corneal hydrops, with a response to the initial questionnaire for 64 (88%) patients and follow-up data at 6 months for 57 (78%) patients. For the 64 confirmed cases the median (interquartile range) age of onset was 31.9 (23.2, 41.3) years and 48 (75%) of the cases occurred in males. A total of 42 (66%) patients were white, 14 (22%) were South Asian, and 7 (11%) were black. The proportion of South Asian and black patients with acute corneal hydrops was significantly higher than in the general population (P<0.001). The minimum estimated annual incidence of acute corneal hydrops in patients with keratoconus was estimated to be 1.43 (1.10, 1.83) per 1000. At 6 months following acute corneal hydrops a decision to proceed with keratoplasty had been made for 12 (20.3%) patients.ConclusionsThis is the first population-based estimate of the incidence of acute corneal hydrops in keratoconus.

The three-surgeon technique for liver tissue dissection: towards real bloodless hepatectomy.

PURPOSE: Bleeding during hepatectomy remains a major cause of mortality despite recent developments in surgical and anaesthetic techniques. To date there is no single surgical device that combines speed, efficient haemostasis and safety for the adjacent vital structures during parenchymal division. This article presents the Three Surgeon Technique (3ST), a novel method of parenchymal dissection for major hepatectomies and compare it with our standard radiofrequency ablation (RFA) - assisted technique. METHODS: 77 patients who underwent major liver resection were divided into two groups: 38 of them (group A) underwent 41 RFA-assisted liver resections and 39 (group B) underwent 41 hepatectomies with the 3ST. The data for the 3ST were prospectively collected and compared to the already collated RFA patient group. RESULTS: Blood transfusion was necessary in 28 and 13 patients in group A and B respectively (p=0.016), with an average of 1.7 and 0.6 units of red blood cells (p<0.001). The Pringle maneuver was not required with the 3ST. The mean time of parenchymal dissection was 90.49 and 77.52 min in group A and B, respectively (p=0.007). CONCLUSION: The 3ST is a novel, reliable and safe alternative to the stand alone RFA-assisted technique. It is a faster procedure, and requires less blood units transfusion.

Serous cystadenocarcinoma of the pancreas: report of a case and management reflections.

BACKGROUND: Serous adenomas represent 1-2% of pancreatic neoplasms and typically are asymptomatic not requiring any treatment and simple observation is the option of choice. Although, they carry a realistic risk of malignancy despite the general view that they never become malignant. We report a case, which, according to our best knowledge is the 27th case reported in the literature. METHODS: We reviewed the literature by performing a search in Pub Med and Medline. RESULTS: A 86-year old patient known to have a serous cystadenoma of the pancreas treated conservatively through a close clinical and radiological follow up which was unattended for 4 years ending up to our emergency department suffering an acute abdomen. Exploratory laparotomy revealed a perforated prepyloric ulcer which was treated accordingly. Patient died some weeks later due to severe medical co morbidities. CONCLUSION: Serous cystic neoplasms of the pancreas carry a realistic risk of malignancy despite the general view that they never become malignant. In our opinion the treatment strategy of serous cystic neoplasms of the pancreas should be aggressive even in cases of remote metastases since prognosis of the disease is satisfactory.

Preclinical development of CAT-354, an IL-13 neutralizing antibody, for the treatment of severe uncontrolled asthma.

BACKGROUND AND PURPOSE: IL-13 is a pleiotropic Th2 cytokine considered likely to play a pivotal role in asthma. Here we describe the preclinical in vitro and in vivo characterization of CAT-354, an IL-13-neutralizing IgG4 monoclonal antibody (mAb), currently in clinical development. EXPERIMENTAL APPROACH: In vitro the potency, specificity and species selectivity of CAT-354 was assayed in TF-1 cells, human umbilical vein endothelial cells and HDLM-2 cells. The ability of CAT-354 to modulate disease-relevant mechanisms was tested in human cells measuring bronchial smooth muscle calcium flux induced by histamine, eotaxin generation by normal lung fibroblasts, CD23 upregulation in peripheral blood mononuclear cells and IgE production by B cells. In vivo CAT-354 was tested on human IL-13-induced air pouch inflammation in mice, ovalbumin-sensitization and challenge in IL-13 humanized mice and antigen challenge in cynomolgus monkeys. KEY RESULTS: CAT-354 has a 165 pM affinity for human IL-13 and functionally neutralized human, human variant associated with asthma and atopy (R130Q) and cynomolgus monkey, but not mouse, IL-13. CAT-354 did not neutralize human IL-4. In vitro CAT-354 functionally inhibited IL-13-induced eotaxin production, an analogue of smooth muscle airways hyperresponsiveness, CD23 upregulation and IgE production. In vivo in humanized mouse and cynomolgus monkey antigen challenge models CAT-354 inhibited airways hyperresponsiveness and bronchoalveolar lavage eosinophilia. CONCLUSIONS AND IMPLICATIONS: CAT-354 is a potent and selective IL-13-neutralizing IgG4 mAb. The preclinical data presented here support the trialling of this mAb in patients with moderate to severe uncontrolled asthma.

The significance of DNA image cytometry and Edmondson-Steiner grading on prognosis after curative resection of hepatocellular carcinoma.

PURPOSE: Hepatocellular carcinoma (HCC) is the commonest primary cancer of the liver. Hepatic resection remains the main curative option, although the incidence of disease recurrence in the remaining hepatic parenchyma is high and accounts for the leading cause of death post resection. For this reason, the need to identify prognostic factors which may determine treatment response and survival is of paramount importance. In this study we assessed whether DNA image cytometry and Edmondson-Steiner grading could be used as prognostic factors in a cohort of patients with HCC undergoing radical hepatic resection. METHODS: Forty-four patients with HCC who underwent radical resection were retrospectively analyzed. Histological grading according to Edmondson and Steiner and DNA ploidy using DNA image cytometry, were the two parameters analyzed. Pearson's x(2) or Fisher's exact tests were used to test for any associations between categorical variables. Univariate semi-parametric Cox proportional hazard regression models were used to assess the effect of explanatory variables on death. All reported p values were based on two-sided tests and compared to a significance level of 0.05. RESULTS: In univariate Cox regression analysis, adverse survival outcome was strongly associated with high DNA score and advanced histological grading. Patients with ploidy score >2.2 had 3.95 times higher probability of death, as compared to those with ploidy score ≤ 2.2. Edmondson-Steiner grades III and IV were also associated with 20.49 and 34.47 higher probability of death respectively as compared to grade I. CONCLUSION: Our results validate the prognostic significance of DNA image cytometry and Edmondson-Steiner grading following curative resection of HCC.

Characteristics of patients presenting with erythema nodosum and sarcoidosis.

We explored the relationship between erythema nodosum (EN) and sex, age, serum angiotensin converting enzyme (ACE), bronchoalveolar lavage lymphocytosis (BAL-I), interstitial granulomas and radiological stage in patients presenting with pulmonary sarcoidosis in Ireland. Sixty-nine patients diagnosed with sarcoidosis between 2003 and 2006 were studied. Forty one patients (59%) were male. Sixteen patients (23%) presented with EN. Forty one patients of 65 (63%) had transbronchial biopsies demonstrating non-caseating granulomas. Patients with sarcoidosis presenting with EN were more likely to be female (p=0.042), younger (p=0.012) and have earlier stage pulmonary disease (p=0.02). There were no correlations between serum ACE, interstitial granulomas and disease stage. BAL-I did however predict increasing disease radiological stage (p=0.042). In this study, one quarter of patients with sarcoidosis presented with EN among their presenting features. These patients were more likely to be young females with early stage radiological disease.

Assessment of the language laterality index in patients with brain tumor using functional MR imaging: effects of thresholding, task selection, and prior surgery.

BACKGROUND AND PURPOSE: Functional MR imaging (fMRI) is used to determine preoperatively the laterality of cortical language representation along with the relationship of language areas to adjacent brain tumors. The purpose of this study was to determine whether changing the statistical threshold for different language tasks influences the language laterality index (LI) for a group of controls, patients with tumor without prior surgery, and patients with tumor and prior surgery. MATERIALS AND METHODS: Seven controls, 9 patients with tumor without prior surgery, and 4 patients with tumor and prior surgery performed verb-generation, phonemic fluency, and semantic fluency language tasks during fMRI. Interhemispheric activation differences between the left and right Broca regions of interest were determined by calculating language LIs. LIs were compared within each group, between groups, and between language tasks. Intraoperative electrocortical mapping or the presence of aphasia during postoperative neurology examinations or both were used as ground truth. RESULTS: The language LI varied as a result of statistical thresholding, presence of tumor, prior surgery, and language task. Although patients and controls followed a similar shape in the LI curve, there was no optimal P value for determining the LI. Three patients demonstrated a shift in the LI between hemispheres as a function of statistical threshold. Verb generation was the least variable task both between tasks and across groups. CONCLUSION: For preoperative patients with tumor, the LI should be examined across a spectrum of P values and a range of tasks to ensure reliability. Our data suggest that the LI may be threshold- and task-dependent, particularly in the presence of adjacent tumor.

Stability of the biodiversity of the surface consortia of Gubbeen, a red-smear cheese.

A total of 1,052 bacteria and 828 yeasts were isolated from the surface flora of 6 batches of Gubbeen cheese made in 1996-1997 and 2002-2003. Stability of the microflora was evaluated over time and also during ripening at 4, 10, and 16 d (batches 4, 5, and 6) or at 4, 16, 23, and 37 d (batches 1, 2, and 3). Bacteria were identified using pulsed-field gel electrophoresis, repetitive extragenic palindromic-PCR, and 16S rRNA gene sequencing, and yeasts were identified by Fourier transform infrared spectroscopy. The bacteria included at least 17 species, of which the most common were Staphylococcus saprophyticus (316 isolates), Corynebacterium casei (248 isolates), Brevibacterium aurantiacum (187 isolates), Corynebacterium variabile (146 isolates), Microbacterium gubbeenense (55 isolates), Staphylococcus equorum/cohnii (31 isolates), and Psychrobacter spp. (26 isolates). The most common yeasts were Debaryomyces hansenii (624 isolates), Candida catenulata (135 isolates), and Candida lusitaniae (62 isolates). In all batches of cheese except batch 2, a progression of bacteria was observed, with staphylococci dominating the early stages of ripening and coryneforms the later stages. No progression of yeast was found. Pulsed-field gel electrophoresis showed that several different strains of the 5 important species of bacteria were present, but generally only one predominated. The commercial strains used for smearing the cheese were recovered, but only in very small numbers early in ripening. Four species, B. aurantiacum, C. casei, C. variabile, and Staph. saprophyticus, were found on all batches of cheese, but their relative importance varied considerably. The results imply that significant variation occurs in the surface microflora of cheese.

Sources of the adventitious microflora of a smear-ripened cheese.

AIMS: To determine the relationships between the major organisms from the cheese-making personnel and environment and the surface of a smear cheese. METHODS AND RESULTS: 360 yeast and 593 bacteria from the cheese surface, the dairy environment and the hands and arms of personnel were collected. Pulsed-field gel electrophoresis, repetitive sequence-based polymerase chain reaction and 16S rDNA sequencing were used for typing and identifying the bacteria, and mitochondrial DNA restriction fragment length polymorphism and Fourier-transform infrared spectroscopy for typing and identifying the yeast. The three most dominant bacteria were Corynebacterium casei, Corynebacterium variabile and Staphylococcus saprophyticus, which were divided into three, five and seven clusters, respectively, by macrorestriction analysis. The same clones from these organisms were isolated on the cheese surface, the dairy environment and the skin of the cheese personnel. Debaryomyces hansenii was the most dominant yeast. CONCLUSIONS: A 'house' microflora exists in the cheese plant. Although the original source of the micro-organisms was not identified, the brines were an important source of S. saprophyticus and D. hansenii and, additionally, the arms and hands of the workers the sources of C. casei and C. variabile. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first time that the major contribution of the house microflora to the ripening of a smear-ripened cheese has been demonstrated.

Rapidly changing pulmonary infiltrates.

Pulmonary eosinophilia responds very quickly to steroid treatment. Chronic pulmonary eosinophilia is common in middle aged females. We report on a patient who presented with subacute onset of shortness of breath, severe weight loss associated with a rise in the peripheral eosinophil count. She was treated successfully with steroids resulting in complete resolution of the pulmonary infiltrates.

Short term treatment with St. John's wort, hypericin or hyperforin fails to induce CYP450 isoforms in the Swiss Webster mouse.

This investigation was designed to determine whether St. John's wort (SJW)(435 mg/kg/d), a readily available antidepressant, or its purported active constituents hypericin (1 mg/kg/d) and hyperforin (10 mg/kg/d) were able to induce various hepatic cytochrome P450 (CYP450) isoforms. SJW, hypericin and hyperforin were administered to male Swiss Webster mice for four consecutive days and hepatic microsomes were prepared on day 5. None of the three treatments resulted in a statistical change in total hepatic CYP450 (SJW treated 0.95 +/- 0.09 nmol/mg vs control 1.09 +/- 0.14 nmol/mg). Furthermore, the catalytic activities of CYP1A2. CYP2E1 and CYP3A were unchanged from control following all three treatments as determined by ethoxyresorufin O-deethylation, p-nitrophenol hydroxylation and erythromycin N-demethylation respectively. Additionally, western immunoblotting demonstrated that there was no significant change in the polypeptide levels of any of the three isoforms. These results indicate that four days of treatment with moderate to high doses of SJW, hyperforin or hypericin fails to induce these CYP450 isoforms in the male Swiss Webster mouse.

Corynebacterium mooreparkense sp. nov. and Corynebacterium casei sp. nov., isolated from the surface of a smear-ripened cheese.

Ten isolates each of two different bacterial species isolated from the surface of a smear-ripened cheese were found to exhibit many characteristics of the genus Corynebacterium. The isolates were Gram-positive, catalase-positive, non-spore-forming rods that did not undergo a rod/coccus transformation when grown on complex media. Chemotaxonomic investigation revealed that the strains belonged unambiguously to the genus Corynebacterium. Their cell walls contained arabinose, galactose and short-chain mycolic acids (C22 to C36) and their peptidoglycan contained meso-diaminopimelic acid. The G+C content of the DNA was 51-60 mol%. MK-9 (H2) was the principal menaquinone. The 16S rDNA sequences of four isolates of each bacterium were determined and aligned with those of other members of the coryneform group. Phylogenetic analysis showed that the strains represented two new sublines within the genus Corynebacterium; Corynebacterium variabile and Corynebacterium ammoniagenes were their nearest known phylogenetic neighbours. Corynebacterium variabile and Corynebacterium ammoniagenes showed the highest levels of sequence homology with the isolates; however, DNA-DNA hydridization studies indicated that the Corynebacterium strains isolated from the cheese smear did not belong to either Corynebacterium variabile or Corynebacterium ammoniagenes (26 and 46% chromosomal similarity, respectively). On the basis of the phylogenetic and phenotypic distinctiveness of the unknown isolates, it is proposed that the bacteria be classified as two new Corynebacterium species, for which the names Corynebacterium mooreparkense sp. nov. and Corynebacterium casei sp. nov. are proposed. Type strains have been deposited in culture collections as Corynebacterium mooreparkense LMG S-19265T (= NCIMB 30131T) and Corynebacterium casei LMG S-19264T (= NCIMB 30130T).

Report of occupational asthma due to phytase and beta-glucanase.

OBJECTIVES: Occupational asthma is the principal cause of respiratory disease in the workplace. The enzymes phytase and beta-glucanase are used in the agricultural industry to optimise the nutritional value of animal feeds. A relation between these enzymes and occupational asthma in a 43 year old man was suspected. METHODS: Inhalation challenge tests were performed with the enzymes phytase, beta-glucanase, and amylase. Skin prick tests were performed with the enzymes diluted to a concentration of 1 mg/ml and 5 mg/ml. Specific IgE to phytase and beta-glucanase were measured with a radioallergosorbent test. RESULTS: Baseline spirometry values were normal. A histamine challenge test showed bronchial hyperreactivity. Exposure to phytase and beta-glucanase led to significant reductions in forced vital capacity and forced expired volume in 1 second. No significant differences were noted after exposure to amylase. Skin tests showed a positive reaction to beta-glucanase (5 mm) at a concentration of 1 mg/ml and positive reactions to beta-glucanase (7 mm) and phytase (5 mm) at a concentration of 5 mg/ml. Similarly specific IgE was present against both phytase and beta-glucanase, at 2.5% and 9.3% binding respectively (2% binding is considered positive). CONCLUSIONS: This is the first description of occupational asthma due to the enzymes phytase and beta-glucanase. Their addition to the ever increasing list of substances associated with occupational asthma will have notable implications for those exposed to these enzymes.

Comparison of the coulometric and polarographic measurement of a high-Dk hydrogel.

BACKGROUND: International Organization for Standardization (ISO) document ISO 9913-1 details procedures for oxygen permeability coefficient (Dk) measurement of hydrogel contact lens materials up to 100 barrer. A draft ISO document 9913-2 describing the coulometric technique states that the recommended procedures are suitable for nonhydrogel materials. New generation hydrogel lens materials exceed 100 barrer, which is outside the scope of both documents. METHODS: A range of rigid gas-permeable materials from Dr. W. Benjamin's standard repository was used as a baseline to assess the accuracy of the polarographic and the coulometric methods. We also measured the permeability of a new generation hydrogel, lotrafilcon A, to explore the suitability of the polarographic and coulometric techniques for high-Dk hydrogel lenses. We modified equipment for both methods that incorporate several improvements including front surface masking to eliminate "edge effect." RESULTS: The coulometric technique provided results similar to those previously reported for the standard rigid gas-permeable materials and yielded relative standard errors typically <10%. The polarographic technique provided results similar to the accepted values for the standard rigid gas-permeable materials Dk <70 barrer only after the edge effect correction algorithm was applied. The polarographic results showed poor precision and significant, systematic differences from accepted values for the rigid gas-permeables with Dk > 70 barrer. CONCLUSIONS: The coulometric method is preferable for the measurement of contact lens materials with permeability >70 barrer. The coulometric method was successfully modified to include hydrogels.