Solution structures by 1H NMR of the novel cyclic trypsin inhibitor SFTI-1 from sunflower seeds and an acyclic permutant

SFTI-1 is a recently discovered cyclic peptide trypsin inhibitor from sunflower seeds comprising 14 amino acid residues. It is the most potent known Bowman-Birk inhibitor and the only naturally occurring cyclic one. The solution structure of SFTI-1 has been determined by 1H-NMR spectroscopy and compared with a synthetic acyclic permutant. The solution structures of both are remarkably similar. The lowest energy structures from each family of 20 structures of cyclic and acyclic SFTI-1 have an rmsd over the backbone and heavy atoms of 0.29 A and 0.66 A, respectively. The structures consist of two short antiparallel beta-strands joined by an extended loop containing the active site at one end. Cyclic SFTI-1 also has a hairpin turn completing the cycle. Both molecules contain particularly stable arrangements of cross-linking hydrogen bonds between the beta-strands and a single disulfide bridge, making them rigid and well defined in solution. These stable arrangements allow both the cyclic and acyclic variants of SFTI-1 to inhibit trypsin with very high potencies (0.5 nM and 12.1 nM, respectively). The cyclic nature of SFTI-1 appears to have evolved to provide higher trypsin inhibition as well as higher stability. The solution structures are similar to the crystal structure of the cyclic inhibitor in complex with trypsin. The lack of a major conformational change upon binding suggests that the structure of SFTI-1 is rigid and already pre-organized for maximal binding due to minimization of entropic losses compared to a more flexible ligand. These properties make SFTI-1 an ideal platform for the design of small peptidic pharmaceuticals or pesticides.

Axillary nerve temperatures during radiofrequency capsulorrhaphy of the shoulder

PURPOSE

The purpose of this study was to determine the temperatures along the course of the axillary nerve during radiofrequency (RF) capsulorrhaphy of the shoulder in a cadaver model. The hypothesis of this project was that temperatures capable of damaging neural tissue would be recorded during simulated RF capsulorrhaphy.

TYPE OF STUDY

Basic science evaluation.

METHODS

This study used 9 fresh-frozen cadaver shoulder capsules removed en bloc along with the underlying axillary nerve and soft tissue. The axillary nerve was instrumented with 4 thermocouples placed along the course of the nerve (2 thermocouples anterior and 2 posterior to the 6 o'clock position, spaced 7 mm apart). Each of the specimens underwent RF thermal capsulorrhaphy during which the temperature at each of the thermocouple positions was continuously recorded.

RESULTS

The average of the maximum temperature at each of the 4 positions measured along the course of the axillary nerve were 52.2 +/- 18.0 degrees C at the most anterior place probed, 45.8 +/- 5.44 degrees C (mid anterior), 44.5 +/- 8.7 degrees C (mid posterior), and 42.8 +/- 10.1 degrees C at the most posteriorly positioned probe. Two specimens had a maximum temperature greater than the 67 degrees C set point of the device, and 7 specimens had a maximum temperature greater than 45 degrees C in at least 1 thermocouple position.

CONCLUSIONS

This study shows that heating of the axillary nerve can occur during RF capsular shrinkage of the shoulder and may potentially reach levels that can damage neural tissue.

Mutations of the beta- and gamma-catenin genes are uncommon in human lung, breast, kidney, cervical and ovarian carcinomas

Beta-catenin forms complexes with Tcf and Lef-1 and functions as a transcriptional activator in the Wnt signalling pathway. Although recent investigations have been focused on the role of the adenomatous polyposis coli (APC)/ beta-catenin/Tcf pathway in human tumorigenesis, there have been very few reports on mutations of the beta-catenin gene in a variety of tumour types. Using PCR and single-strand conformational polymorphism analysis, we examined 93 lung, 9 breast, 6 kidney, 19 cervical and 7 ovarian carcinoma cell lines for mutations in exon 3 of the beta-catenin gene. In addition, we tested these same samples for mutations in the NH2-terminal regulatory region of the gamma-catenin gene. Mutational analysis for the entire coding region of beta-catenin cDNA was also undertaken in 20 lung, 9 breast, 5 kidney and 6 cervical carcinoma cell lines. Deletion of most beta-catenin coding exons was confirmed in line NCI-H28 (lung mesothelioma) and a silent mutation at codon 214 in exon 5 was found in HeLa (cervical adenocarcinoma). A missense mutation at codon 19 and a silent mutation at codon 28 in the NH2-terminal regulatory region of the gamma-catenin gene were found in H1726 (squamous cell lung carcinoma) and H1048 (small cell lung carcinoma), respectively. Neither deletions nor mutations of these genes were detected in the other cell lines examined. These results suggest that beta- and gamma-catenins are infrequent mutational targets during development of human lung, breast, kidney, cervical and ovarian carcinomas.

Plasma sodium-osmotic dissociation and hormonal interaction with drinking-induced hypervolemia at 2800 m altitude

PURPOSE

To study hormonal factors that may account for the dissociation between beverage-induced plasma sodium p[Na+] and osmotic p[Osm] concentrations that appear to refute the high theoretical correlation between p[Na+] and p[Osm].

METHODS

Ten men (24 +/- SD 3 yr of age) sat reclining (head up) for 12 h in a chamber (21-23 degrees C dry bulb, 25-33% relative humidity) at 2800 m (9184 ft, 539 mm Hg) altitude (ALT), and at 321 m (1053 ft, 732 mm Hg) on the ground (GND). During 1000-1030 hours they consumed 3 fluids (12 ml x kg(-1),X = 948 ml x d(-1)) with large differences in sodium and osmotic contents: AstroAde (AA) with 185 mEq x L(-1) Na+ and 283 mOsm x kg(-1), Performance 1 (Shaklee) (P1) with 22 mEq x L(-1) Na+ and 365 mOsm kg(-1), or H2O at ALT; and only H2O on the GND.

RESULTS

After drinking: plasma volume (PV) increased at 1200 hours by 8.3% (p < 0.05) with AA but was not significantly (NS) changed in the other sessions (Xdelta = +0.9%, range -0.9 to 2.8%); p[Na+] and p[Osm] were unchanged. Urinary rates and free-water clearances were attenuated with AA and P1 vs. those with H2O. Correlations between and among p[Na+] and p[Osm] suggest that the pNa+ ion is more tightly controlled than pOsm; and that there was no clear hormonal response that could account for this dissociation from theoretical considerations.

CONCLUSIONS

There is significant dissociation between plasma sodium and osmotic concentrations after fluid intake. Induction and maintenance of hypervolemia requires increased (near isotonic) drink Na+ osmols rather than increased non-ionic osmols.

Recovery of Cardiac Function after Standard Hypothermic Storage Versus Preservation with Peg-Hemoglobin

Preservation of the heart for transplantation after infusion of cardioplegia and extirpation of a cardiac allograft results in an ischemic insult to the myocardium. This ischemic insult may lead to a loss of function in the transplanted heart. Hypothermic perfusion preservation with an oxygen hemoglobin carrying solution may avert ischemic injury and lead to improved recovery of cardiac function. The purpose of this study was to compare cardiac function after 8 hours of continuous hypothermic perfusion with a unique polyethylene-glycol-hemoglobin (PEG-Hb) solution to hearts preserved by 4 hours of hypothermic ischemic storage. Freshly extirpated hearts served as functional controls. The hearts of 26 anesthetized and intubated New Zealand white rabbits were harvested after cold cardioplegic arrest. Group I (n = 12) hearts were perfused with a PEG-Hb solution at 20 degrees C and 30 mm Hg for 8 hours. PO2 was maintained > or = 500 mm Hg. Group II (n = 7) hearts were preserved by cold ischemic storage for 4 hours at 4 degrees C. Group III (n = 7) were tested immediately after harvest. Left ventricular (LV) function was measured in the nonworking state at 15 minutes, 1 hour, and 2 hours after transfer to a standard crystalloid Langendorff circuit. Measurement of LV developed pressure, peak + dP/dt and -dP/dt revealed a superior trend between Group I and Group II hearts in comparison with freshly extirpated hearts. Heart rate was similar among all groups throughout testing (p = ns). Coronary blood flow was not significantly different between groups. Continuous perfusion preservation of rabbit hearts for 8 hours with PEG-Hb solution at 30 mm Hg and 20 degrees C yielded LV function that was similar to 4 hours of ischemic hypothermic storage. Furthermore, return of cardiac function after 8 hours of perfusion preservation using this PEG-Hb solution may be superior to that obtained in freshly extirpated hearts. These data suggest that some recovery of myocardial function may occur during perfusion preservation with this PEG-Hb solution after the ischemic insult of cardioplegic arrest. Continuous perfusion preservation using this PEG-Hb solution deserves further investigation in large animal transplant models.

Adjusting interphase FISH results in epithelial tissue sections to whole cell complement

OBJECTIVE

To derive an equation to compensate for the discrepancies between whole cell preparations and tissue sections for more accurate enumeration of fluorescence in situ hybridization (FISH) signals per cell.

STUDY DESIGN

Mean centromere signal counts in touch preparations and corresponding 4-6-micron sections of paraffin-embedded tissue were calculated. Mean widest nuclear diameters were also determined from the tissue sections. The observed data were analyzed to define the volumetric relationships between tissue sections and whole cell preparations.

RESULTS

Analysis of results from six lung specimens yielded an equation that approximates whole versus sectioned nuclear volume and permits accurate quantification of mean FISH signal count in histologic sections, as follows: [formula: see text].

A Numerical Simulation of the Diffusion of Near Infrared Light Through Brain Tissue

A numerical simulation of the transport of light energy in the near infrared region of the spectrum through human brain tissue is presented. This simulation models the use of near infrared spectroscopic techniques to quantify the levels of oxygen present in brain tissue. Successful application of the technique requires knowledge of the optical pathlength in the tissue, and it is the goal of this simulation to quantify the relationship of the optical pathlength and the oxygenation state of the tissue. Both implicit and explicit finite element schemes for unstructured grids are implemented and discussed. Several application simulations using three tissue grids of varying degrees of physiological accuracy are then conducted, and figures for the optical pathlength of light through the tissue at varying levels of oxygenation are computed. These results are then used to develop a quantitative relationship between the pathlength and the absorption parameter for the three tissue models which we explore.

Factors modulating the epithelial response to toxicants in tracheobronchial airways

As one of the principal interfaces between the organism and the environment, the respiratory system is a target for a wide variety of toxicants and carcinogens. The cellular and architectural complexity of the respiratory system appears to play a major role in defining the focal nature of the pulmonary response to environmental stressors. This review will address the biological factors that modulate the response of one of the major target compartments within the respiratory system, the tracheobronchial airway tree. Individual airway segments respond uniquely to toxic stress and this response involves not only the target cell population, e.g. epithelium, but also other components of the airway wall suggesting a trophic interaction within all components of the airway wall in maintaining steady state and responding to injury. A number of biological factors modulate the nature of the response, including: (1) metabolic potential at specific sites for activation and detoxification; (2) the nature of the local inflammatory response; (3) age of the organism at the time of exposure; (4) gender of the exposed organism; (5) history of previous exposure; and (6) species and strain of the organism exposed.

A randomized controlled study of the use of transscleral diode laser and cryotherapy in the management of rhegmatogenous retinal detachment

PURPOSE

Cryotherapy, the most common modality used to create a chorioretinal adhesion during retinal reattachment surgery, is associated with the dispersion of viable pigment epithelial cells and breakdown of the blood-ocular barrier, which are thought to be causative in a number of postoperative events, including macular pucker, proliferative vitreoretinopathy (PVR), and cystoid macular edema. Transscleral diode laser has been used successfully to create a chorioretinal adhesion in retinal reattachment surgery (diopexy) and experimentally has been shown to cause less pigment dispersion and blood-ocular barrier breakdown than cryotherapy. The authors carried out a prospective randomized study to compare the results and complication rates of transscleral diopexy with those of cryopexy during surgery for rhegmatogenous retinal detachment (RRD).

METHODS

Data from 120 patients with recent onset RRD without significant PVR who were suitable for scleral buckling surgery and randomized to treatment using diode laser or cryotherapy were analyzed. The primary outcome measure was reattachment at 6 months with one operation. Secondary outcome measures were pain and swelling on the first postoperative day, cystoid macular edema as assessed angiographically at 6 weeks, and visual acuity, macular epiretinal membrane, and pigment migration under the fovea at 3 months.

RESULTS

There was no significant difference between the primary and secondary outcome measures between the two treatment groups, with a primary success rate of 83% in the diode group and 92% in the cryotherapy group. Pain and postoperative swelling on the first postoperative day were equivalent. Cystoid macular edema was angiographically present in 12% in the diode group and 14% in the cryotherapy group. Visual acuity of at least 20/40 was achieved in 54% of patients in both groups. The rate of PVR was 5% in the diode group and 3% in the cryotherapy group.

CONCLUSION

In this study of patients with uncomplicated RD without significant preoperative PVR, the experimentally shown benefits of transscleral diode laser did not result in significant improvement in the results of reattachment surgery compared with cryotherapy.

Gene therapy for pulmonary diseases

Gene therapy for pulmonary disease has attracted a great deal of attention since the first report of successful gene delivery 10 years ago. Potential indications for gene therapy include chronic illnesses such as cystic fibrosis and alpha(1)-antitrypsin deficiency, and acute illnesses such as acute transplant rejection and chemotherapy-induced lung injury. The key technological impediment to successful gene therapy is vector optimization. Viral vectors, including adenovirus and adeno-associated virus, have relatively low efficiency in vivo. In addition, adenovirus has been associated with a brisk inflammatory response and limited duration of expression in the lung. Nonviral vectors, particularly liposomes, have also been tried, with limited expression efficiency and some toxicity. Although work is ongoing to improve adenoviral and adeno-associated viral vectors and test other viral and nonviral vectors, an ideal vector has not yet been identified. Several important barriers to successful gene therapy, including the host inflammatory response, promotor down-regulation, tissue-specific targeting, and physical barriers to gene delivery in the airway, will need to be overcome. Despite these daunting problems, several human gene therapy trials have been completed, using adenovirus, adeno-associated virus, and liposomes. In general, these trials have been focused on safety, and have shown that there is dose-dependent inflammation in response to adenovirus. Adeno-associated virus appears to cause little inflammation. Demonstration of successful gene delivery and transcription has been quite variable in human trials. In general, the level of expression of transgene appears to be quite low. In summary, although there is great promise for gene therapy in the lung, significant challenges remain in translating this technology to successful human therapy.

Interleukin 20: discovery, receptor identification, and role in epidermal function

A structural, profile-based algorithm was used to identify interleukin 20 (IL-20), a novel IL-10 homolog. Chromosomal localization of IL-20 led to the discovery of an IL-10 family cytokine cluster. Overexpression of IL-20 in transgenic (TG) mice causes neonatal lethality with skin abnormalities including aberrant epidermal differentiation. Recombinant IL-20 protein stimulates a signal transduction pathway through STAT3 in a keratinocyte cell line, demonstrating a direct action of this ligand. An IL-20 receptor was identified as a heterodimer of two orphan class II cytokine receptor subunits. Both receptor subunits are expressed in skin and are dramatically upregulated in psoriatic skin. Taken together, these results demonstrate a role in epidermal function and psoriasis for IL-20, a novel cytokine identified solely by bioinformatics analysis.

Time perception in boys with attention-deficit/hyperactivity disorder according to time duration, distraction and mode of presentation

In a recent theoretical model of attention-deficit/hyperactivity disorder (ADHD), Barkley (1997a) predicted that ADHD children experience impairments in their psychological sense of time. This was demonstrated in a series of experiments by Barkley, Koplowicz, Anderson, and McMurray (1997). The present study sought to investigate the effects of ADHD subtype, stimulus duration, mode of presentation (visual versus auditory) and distractors on the performance of a simple time reproduction task. Data were obtained from 44 ADHD children (14 predominantly inattentive and 30 combined type) and 44 age-matched Controls using the Time Perception Application version 1.0 (Barkley, University of Massachusetts Medical Center, 1998). Results revealed that the ADHD children made significantly larger errors on Visual time reproduction tasks than the Controls, regardless of ADHD subtype or the presence of distractors. Furthermore, ADHD children were more likely to overestimate the shorter time intervals (0.5 and 2 s) and underestimate the longer time intervals (3, 4 and 6 s) relative to Controls. No group differences were observed on the auditory time reproduction task, with both ADHD and Control groups consistently underestimating the durations to be reproduced. The results of this study provide further support for the prediction that children with ADHD have an impaired sense of time.

Recombinant VIIa concentrate in the management of bleeding following prothrombin complex concentrate-related myocardial infarction in patients with haemophilia and inhibitors

Prothrombin complex concentrates (PCCs) and, more recently, activated prothrombin complex concentrates (APCCs), are widely used for the treatment of active bleeding in haemophiliacs with inhibitors. Myocardial infarction (MI), associated with the use of these concentrates, is a well-recognized, but uncommon, complication. We review the 14 previous cases published in the literature and describe two additional patients. MI related to the use of activated and non-activated PCCs predominantly affects young patients who often have no preceding history of, or risk factors for, MI and tends to be associated with large cumulative doses of concentrate. The most frequent pathological finding is myocardial haemorrhage, with no evidence of coronary artery atheroma or thrombosis. The management of further bleeding in these patients is difficult. We have safely used recombinant factor VIIa to treat bleeding in the immediate and long-term period following PCC-related MI.

Effects of an oral vasopressin receptor antagonist (OPC-31260) in a dog with syndrome of inappropriate secretion of antidiuretic hormone

OBJECTIVE

The syndrome of inappropriate secretion of antidiuretic hormone is a rare disorder in dogs characterised by hypo-osmolality and persistent arginine vasopressin production in the absence of hypovolaemia and/or hypotension. The study describes the efficacy and safety of the nonpeptide selective arginine vasopressin V2 receptor antagonist OPC-31260 in a dog with the naturally occurring syndrome.

DESIGN

The detailed case history of a dog with spontaneous syndrome of inappropriate secretion of antidiuretic hormone that received long-term therapy with oral OPC-31260 is presented. Effects of the first dose of OPC-31260 and of a dose administered after a continuous dosing period of 12 days are reported.

PROCEDURE

Packed cell volume, plasma sodium, total protein, arginine vasopressin, renin activity, atrial natriuretic peptide, urine specific gravity, urine output, heart rate and body weight were monitored for 2 h before, and for 4 h after, the first dose of OPC-31260. The same parameters plus plasma osmolality and urine osmolality were monitored when an identical dose was administered after 12 days of therapy.

RESULTS

Oral administration of OPC-31260 at 3 mg/kg body weight resulted in marked aquaresis with increased urine output and decline in urine specific gravity within 1 h. Corresponding increases in concentrations of plasma sodium, plasma osmolality and plasma renin activity were recorded over a 4 h period. Arginine vasopressin concentration remained inappropriately elevated throughout the study. Results were similar when the trial procedure was repeated after a stabilisation period of 12 days. Long-term therapy with OPC-31260 at a dose of 3 mg/kg body weight orally every 12 h resulted in good control of clinical signs with no deleterious effects detected during a 3-year follow-up period. Despite sustained clinical benefits observed in this case, plasma sodium did not normalise with continued administration of the drug.

CONCLUSIONS

Treatment of a dog with naturally occurring syndrome of inappropriate secretion of antidiuretic hormone with OPC-31260 at 3 mg/kg body weight orally every 12 h resulted in marked aquaresis and significant palliation of clinical signs with no discernible side-effects detected over a 3-year period. Thus, OPC-31260 appears to offer a feasible medical alternative to water restriction for treatment of dogs with syndrome of inappropriate secretion of antidiuretic hormone. Higher doses of OPC-31260 may be required to achieve and maintain normal plasma sodium in dogs with this syndrome.

The impact of open access flexible sigmoidoscopy: a comparison of two services

BACKGROUND

Open access flexible sigmoidoscopy (OAFS) is an integral part of colorectal cancer services. This study compares the impact of two types of open-access flexible sigmoidoscopy services on the utilisation of barium enema and tumour-stage migration.

METHODS

This was a non-randomised comparison (over two one-year periods, four years apart) of two unselected groups of patients, with different inclusion criteria, in adjacent similarly populated health districts. One offered a nurse practitioner endoscopy service while the other had a doctor-led colorectal clinic.

RESULTS

The doctor-led service with its broad inclusion criteria detected more colorectal cancers [13.2% versus 0.7%; OR = 16.05; 2.16-119.2]. Neither nurse practitioner (130 cases) nor doctor-led (262 cases) flexible sigmoidoscopy reduced the total number of barium enemas [Odds Ratio (OR) = 1.16 (95% CI 1.03-1.3)]. However, the doctor-led service did reduce the number of barium enemas requested by general practitioners (from 249 to 152). The total number of colorectal cancers (detected by all available methods) were similar [OR = 0.82 (0.53-1.25)] and both services resulted in a similar tumour-stage migration [OR = 1.39 (0.31-6.23)].

CONCLUSION

Open access flexible sigmoidoscopy services have minimal impact on the utilisation of radiology services. Broader inclusion criteria of doctor-led services produce a higher cancer-yield. Tumour-stage migration may be related to greater awareness of colorectal cancer symptoms rather than to the type of OAFS.

Altered HOX and WNT7A expression in human lung cancer

HOX genes encode transcription factors that control patterning and cell fates. Alterations in HOX expression have been clearly implicated in leukemia, but their role in most other malignant diseases remains unknown. By using degenerate reverse transcription-PCR and subsequent real-time quantitative assays, we examined HOX expression in lung cancer cell lines, direct tumor-control pairs, and bronchial epithelial cultures. As in leukemia, genes of the HOX9 paralogous group and HOXA10 were frequently overexpressed. For HOXB9, we confirmed that elevated RNA was associated with protein overexpression. In some cases, marked HOX overexpression was associated with elevated FGF10 and FGF17. During development, the WNT pathway affects cell fate, polarity, and proliferation, and WNT7a has been implicated in the maintenance of HOX expression. In contrast to normal lung and mortal short-term bronchial epithelial cultures, WNT7a was frequently reduced or absent in lung cancers. In immortalized bronchial epithelial cells, WNT7a was lost concomitantly with HOXA1, and a statistically significant correlation between the expression of both genes was observed in lung cancer cell lines. Furthermore, we identified a homozygous deletion of beta-catenin in the mesothelioma, NCI-H28, associated with reduced WNT7a and the lowest overall cell line expression of HOXA1, HOXA7, HOXA9, and HOXA10, whereas HOXB9 levels were unaffected. Of note, both WNT7a and beta-catenin are encoded on chromosome 3p, which undergoes frequent loss of heterozygosity in these tumors. Our results suggest that alterations in regulatory circuits involving HOX, WNT, and possibly fibroblast growth factor pathways occur frequently in lung cancer.

Interleukin 21 and its receptor are involved in NK cell expansion and regulation of lymphocyte function

Cytokines are important in the regulation of haematopoiesis and immune responses, and can influence lymphocyte development. Here we have identified a class I cytokine receptor that is selectively expressed in lymphoid tissues and is capable of signal transduction. The full-length receptor was expressed in BaF3 cells, which created a functional assay for ligand detection and cloning. Conditioned media from activated human CD3+ T cells supported proliferation of the assay cell line. We constructed a complementary DNA expression library from activated human CD3+ T cells, and identified a cytokine with a four-helix-bundle structure using functional cloning. This cytokine is most closely related to IL2 and IL15, and has been designated IL21 with the receptor designated IL21 R. In vitro assays suggest that IL21 has a role in the proliferation and maturation of natural killer (NK) cell populations from bone marrow, in the proliferation of mature B-cell populations co-stimulated with anti-CD40, and in the proliferation of T cells co-stimulated with anti-CD3.

Detecting gene copy number fluctuations in tumor cells by microarray analysis of genomic representations

In this work, we explore the use of representations in conjunction with DNA microarray technology to measure gene copy number changes in cancer. We demonstrate that arrays of DNA probes derived from low-complexity representations can be used to detect amplifications, deletions, and polymorphic differences when hybridized to representations of genomic DNA. The method is both reproducible and verifiable, and is applicable even to microscopic amounts of primary tumors. We also present a mathematical model for array performance that is useful for designing and understanding DNA microarray hybridization protocols. The future applications and challenges of this approach are discussed.

Molecular analysis of FRIGIDA, a major determinant of natural variation in Arabidopsis flowering time

Vernalization, the acceleration of flowering by a long period of cold temperature, ensures that many plants overwinter vegetatively and flower in spring. In Arabidopsis, allelic variation at the FRIGIDA (FRI) locus is a major determinant of natural variation in flowering time. Dominant alleles of FRI confer late flowering, which is reversed to earliness by vernalization. We cloned FRI and analyzed the molecular basis of the allelic variation. Most of the early-flowering ecotypes analyzed carry FRI alleles containing one of two different deletions that disrupt the open reading frame. Loss-of-function mutations at FRI have thus provided the basis for the evolution of many early-flowering ecotypes.

The nurse practitioner endoscopist

Most upper and lower gastrointestinal endoscopies in Great Britain and Ireland are performed by surgeons, physicians or radiologists. Since the introduction of the 'nurse endoscopist' by the British Society of Gastroenterology Working Party, few centres in the UK have adopted this policy. We have reviewed the anxiety about nurse practitioner endoscopists among patients and physicians. Finally, the role and future of the nurse practitioner endoscopist in the UK is discussed.