Use of a mobile device app: a potential new tool for poster presentations and surgical education.

INTRODUCTION: Poster presentations are an important part of presenting scientific techniques and represent an integral part of conferences and meetings. Traditionally, paper format is used; however, in recent years electronic posters and other methods, such as incorporating a DVD player as part of a poster, have been successfully used. We describe and demonstrate the use of an augmented reality application for smartphones and tablets as a potential future addition to the presentation of scientific work and surgical techniques in poster format. This method allows the audience to view surgical techniques and research as 3D animation or video by using a trigger image in a poster/journal/text book via their smart device. METHOD: The author used the free Aurasma© application available on both iOS and Android 2.2 and higher platforms from iTunes App Store and Google Play. Once installed, any user with a 3G or WiFi connection via a smart phone or tablet can subscribe to the Medical Illustration channel for free. The user can then scan the trigger image placed on a poster with a mobile device to view videos, animations or 3D data. Further interaction can direct the user to a website for more content. RESULT: The author has trialled this method at a regional burns and plastic surgery centre and found it to be highly effective. CONCLUSION: The use of this novel method adds a new dimension to the presentation of scientific work at surgical and medical conferences and as part of journals and textbooks by permitting users to view scientific data and techniques on mobile devices as videos or as three dimensional environments at their own leisure.

Tumor necrosis factor-alpha in cisplatin nephrotoxicity: a homebred foe?

A robust inflammatory response involving tumor necrosis factor-alpha (TNF-alpha) is induced during cisplatin nephrotoxicity. Using chimeric models, Reeves and colleagues now demonstrate that resident kidney cells, rather than infiltrating immune cells, are the major producers of TNF-alpha. Blockade of TNF-alpha attenuates inflammation and associated kidney injury.

Acute retinal necrosis: insights into pathogenesis from the mouse model.

Acute retinal necrosis (ARN) is a relatively rare syndrome that is caused by infection with one of several members of the human herpesvirus family. ARN usually occurs in otherwise healthy patients, although it has also been observed in immunocompromised individuals. It is characterized by retinal vasculitis and haemorrhaging, areas of retinal necrosis, vitreous and aqueous inflammation and optic neuritis. It may affect one or both eyes and frequently results in severely reduced vision or blindness in the affected eye. Results using the mouse model of ARN have provided insight into the pathogenesis of this disease. However, many unanswered questions remain, such as why does only a very small fraction of individuals infected with one or more herpesvirus develop ARN? Increased understanding of the interactions of herpesviruses with T cells and cytokines may enable the development of therapeutic strategies targeted specifically to control viral infection in the eye and/or brain.

Murine cytomegalovirus infection causes apoptosis of uninfected retinal cells.

PURPOSE: To determine the role of apoptosis in prevention and/or exacerbation of retinal disease in a mouse model of cytomegalovirus retinitis. METHODS: Immunocompetent or T-cell- depleted BALB/c mice were injected with murine cytomegalovirus (MCMV) by supraciliary injection. On sequential days after infection, mice were killed, and eyes were harvested for cryosectioning or for DNA extraction. Ocular sections were stained with monoclonal antibodies specific for MCMV or for T cells or used in the TdT-dUTP terminal nick-end labeling (TUNEL) assay to detect apoptotic cells. RESULTS: In immunocompetent BALB/c mice, TUNEL assays revealed that a large area of the retina was apoptotic in relation to the relatively small number of MCMV-infected cells that were observed in the subjacent choroid and/or retinal pigment epithelium. In infected eyes from T-cell- depleted mice, there were more TUNEL-positive cells, and the areas of apoptosis were more extensive than in immunocompetent mice. These observations correlated with the increased extent of MCMV infection that is observed in the eyes of T-cell- depleted mice. However, irrespective of immune status, TUNEL-positive apoptotic cells were present mainly in areas of the retina overlying areas of MCMV-infected choroid and/or retinal pigment epithelium. More intense DNA laddering, indicative of increased apoptosis, was observed in the posterior segments of the eyes of T-cell- depleted mice after supraciliary inoculation with murine cytomegalovirus compared with less intense DNA laddering in the posterior segments of eyes of immunocompetent MCMV-infected mice. CONCLUSIONS: The ability of the mouse's immune system to control MCMV infections in some tissues depends on induction of apoptosis in virus-infected cells. However, in the retina, cells undergoing apoptosis were not virus-infected, a finding that suggests that apoptosis of uninfected retinal cells may play a role in the pathogenesis of MCMV retinitis.

Verification of dynamic multileaf collimation using an electronic portal imaging device.

High standards of treatment verification are necessary where complex new delivery techniques, such as intensity modulated radiation therapy using dynamic multileaf collimation, are being developed. This paper describes the use of a fluoroscopic electronic portal imaging device (EPID) to provide real-time qualitative verification of leaf position during delivery of a dynamic MLC prescription in addition to off-line quantitative verification. A custom-built circuit triggers the EPID to capture a series of snap-shot images at equally spaced dose points during a dynamic MLC prescription. Real-time verification is achieved by overlaying a template of expected leaf positions onto the images as they are acquired. Quantitative off-line verification is achieved using a maximum gradient edge detection algorithm to measure individual leaf positions for comparison with required leaf positions. Investigations have been undertaken to optimize image acquisition and assess the edge detection algorithm for variations in machine dose rate, leaf velocity and beam attenuation. On-line verification enables the operator to monitor the progress of a dynamic delivery and has been used for independent confirmation of accurate dynamic delivery during intensity modulated treatments. Off-line verification allows measurement of leaf position with a precision of 1 mm although image acquisition times must be less than or equal to 140 ms to ensure coincidence of the maximum gradient in the image with the 50% dose level.

Natural killer cells prevent direct anterior-to-posterior spread of herpes simplex virus type 1 in the eye.

PURPOSE: Anterior chamber (AC) inoculation of the KOS strain of herpes simplex virus type 1 (HSV-1) results in morphologic sparing of the ipsilateral retina, whereas the retina of the uninoculated contralateral eye becomes infected and undergoes acute retinal necrosis. Natural killer (NK) cells are an important component of the primary immune response to most virus infections. The purpose of this study was to determine whether NK cells are involved in preventing early direct anterior-to-posterior spread of HSV-1 after AC inoculation. METHODS: Normal BALB/c mice were inoculated with 4 X 10(4) plaque-forming units (PFU) of the KOS strain of HSV-1 using the AC route. NK activity was measured in the spleen, the superficial cervical and submandibular lymph nodes, and the inoculated eye by lysis of chromium-labeled, NK-sensitive YAC-1 target cells. Histopathologic scoring and immunohistochemical staining for HSV-1 were performed in NK-depleted (injected intravenously with anti-asialo GM1) or mock-depleted (injected intravenously with normal rabbit serum) mice. RESULTS: In mock-depleted mice, NK activity in the spleens, superficial cervical and submandibular lymph nodes, and inoculated eyes peaked at postinoculation (pi) day 5 and declined by pi day 7. Treatment with anti-asialo GM1 eliminated NK activity in the eye and at nonocular sites. The histopathologic scores at pi day 5 indicated more damage to the retinas of NK-depleted mice than to those of mock-depleted mice, and immunohistochemical staining for HSV-1 showed spread of the virus to the sensory retina only in NK-depleted mice. CONCLUSIONS: NK cells were activated within 5 days after AC inoculation of the KOS strain of HSV-1. Activation of NK cells appears to play a role in preventing direct anterior-to-posterior spread of the virus in the inoculated eye which, in turn, protects the retina of this eye and helps to explain why the architecture of the retina of this eye is spared.

Fluorescence studies of lens epithelial cells and their constituents.

Steady-state and time-resolved fluorescence measurements have been made of human and rabbit lens epithelial cells and their total soluble protein. Excitation at 350 nm results in broad fluorescence spectra peaking at 450 nm and stretching into the visible past 650 nm. The fluorescence excitation spectra peak around 350 nm. We assign the species responsible for this absorption and fluorescence as NADPH. Because the absorption of near-UV light (300-400 nm) is responsible for cell damage and death, we postulate that excited states of NADPH are implicated in the mechanisms of cell damage. Preirradiation with 355 nm light leads to a loss of NADPH fluorescence but with no change in decay kinetics. Possible mechanisms for cell damage are explored.

Protection against murine cytomegalovirus retinitis by adoptive transfer of virus-specific CD8+ T cells.

PURPOSE: Human cytomegalovirus retinitis, the most common ophthalmic infection of AIDS patients, has been modeled in BALB/c mice infected with murine cytomegalovirus by the supraciliary route. A series of depletion and adoptive transfer studies was performed to determine whether adoptive transfer of T cells protects mice from retinitis caused by murine cytomegalovirus infection after supraciliary inoculation and to determine which subset of T cells is responsible for protection. METHODS: BALB/c mice were thymectomized and T cell-depleted by injection of monoclonal antibodies to CD4, CD8, or both. Murine cytomegalovirus (9 x 10(2) plaque forming units [pfu]) was injected into the supraciliary space. Experimental animals received murine cytomegalovirus-specific T cells or subsets of T cells 2 hours before virus injection, whereas control animals received herpes simplex virus type 1-specific T cells by tail vein injection. Eight days after virus injection, retinal pathology was scored by histopathologic examination of hematoxylin and eosin-stained ocular sections. RESULTS: CD8+ T cell depletion was sufficient for development of retinitis after supraciliary injection of murine cytomegalovirus. Adoptive transfer of murine cytomegalovirus-specific T cells, but not herpes simplex virus type 1-specific T cells, provided protection from retinitis. Additionally, separation of the murine cytomegalovirus-specific T cells into CD8+ and CD4+ subsets before adoptive transfer showed that the CD8+ fraction of the adoptive T cells was responsible for protection. CONCLUSIONS: These results suggest that adoptive transfer of cytomegalovirus-specific T cells or T cell subsets might be used to treat or prevent cytomegalovirus retinitis in immunosuppressed human patients.

Is there a risk of cytomegalovirus transmission during in vitro fertilization with donated oocytes?

OBJECTIVE: To define the risk of human cytomegalovirus (HCMV) transmission from donated oocytes. DESIGN: Prospective study. SETTING: University IVF program. PATIENT(S): Sixty-seven couples undergoing 72 cycles of IVF-ET. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Serum from both partners (women: n = 71; men: n = 60) was obtained for detection of antibodies to HCMV. Semen before preparation (n = 53), sperm after preparation (Percoll gradient; n = 47), cervical mucus aspirated at the time of oocyte aspiration (n = 70), and uninseminated oocytes and embryos not suitable for cryopreservation (n = 568) were frozen in liquid nitrogen. Polymerase chain reaction was used for detection of HCMV (immediate early 1 gene) in all samples collected. RESULT(S): Serum antibodies to HCMV were found in 62% of the women and 37% of the men tested. Human cytomegalovirus DNA was detected in 25% of the ejaculates and in 19% of the cervical mucus samples. There was no amplification of HCMV DNA from oocytes or embryos. CONCLUSION(S): Because we were unable to amplify HCMV DNA from any of the oocytes or embryos, it seems unlikely that HCMV is transmissible through oocyte or embryo donation.

The performance of a fluoroscopic electronic portal imaging device modified for portability.

Advances in external beam therapy technology have made routine, efficient conformal therapy a reality. With it comes the increasing need for online treatment verification, which is only achievable at present through the use of electronic portal imaging devices (EPIDs). For a large radiotherapy centre, the provision of one EPID per treatment machine proves extremely expensive. This paper details modifications to the design of a commercial fluoroscopic EPID (the SRI-100) to produce a portable system, capable of providing quick, high quality imaging on more than one treatment machine. We describe the necessary hardware and software changes made to the system, as well as the variety of mechanical and quality control checks performed for testing the stability and quality of the imaging. The modified system has been found to be both electronically and mechanically robust, with associated image quality, scaling, distortion and movement similar to other EPIDs in the department. Although the modification was designed specifically to allow for the acquisition of images from multiple treatment machines, it may also enable the operation of the EPID for other uses such as total body irradiation (TBI) treatment verification and a further range of quality control procedures on the linear accelerator itself.

A system for maintaining the educational and training standards of junior doctors.

The development of junior doctors' competence is complex because the hospital environment in which doctors work places many demands on them. The need for quality education and training and personal development may be in direct conflict with the service commitments required from hospitals. This paper describes the methods by which the Postgraduate Medical. Council of New South Wales, Australia, addresses the needs of junior doctors in the state in order to improve the quality of their education. Key elements of the Council's function include the provision of hospital clinical supervisors who oversee junior doctor education and training, and central involvement in supplying the junior doctor workforce to all state hospitals who must meet defined accreditation standards. This paper also provides data on evaluation of those methods and some educational outcomes.

Acute severe asthma treated by mechanical ventilation: a comparison of the changing characteristics over a 17 yr period.

Recorded cases of asthma have increased in recent years. It is unclear, however, whether this apparent increase in prevalence is accompanied by an increase in severity of the disorder. One potential measure of asthma severity is the requirement for mechanical ventilation. This paper examines those patients ventilated for severe asthma in a district general hospital over a 17 yr period. Since the methods used to assess asthma attacks and the criteria for instituting mechanical ventilation in this hospital did not alter between 1973 and 1992 (Jones criteria), it was possible to compare directly characteristics of all ventilated patients during the study period. The comparison showed that there was a significant increase between the two study periods in the number of patients who required mechanical ventilation. Moreover, in the more recent period both the subjective speed of onset of the asthma attack and the objective time between admission and ventilation were significantly shorter. However, despite this increase in asthma severity the mortality and morbidity in the more recent study period were lower. Overall the results of this study support the view that, in the population served by our district general hospital, asthma has increased in severity. This increased severity is indicated by an increase in the number of patients requiring mechanical ventilation and in the rapidity with which attacks evolved. However, for patients in whom ventilation was required, improved care has lowered both morbidity and mortality.

NK cell modulation of murine cytomegalovirus retinitis.

CMV retinitis, the most common ophthalmic infection of AIDS patients, causes blindness if left untreated. To study the role of NK cells in the modulation of CMV ocular infection, 9.0 x 10(2) plaque-forming units of the Smith strain of murine CMV (MCMV) was injected into the supraciliary space of the left eyes of BALB/c mice. Lysis of NK-sensitive target cells (YAC-1) by effectors from the draining lymph nodes peaked at day 5 postinfection, while the splenic cytolytic response was biphasic, with peaks at days 2 and 7 postinfection. Flow cytometry showed that NK cells (DX-5+) increased in spleens and eyes 5 days after supraciliary infection with MCMV compared with uninfected or mock-infected controls. Eight days after supraciliary injection with 9.0 x 10(2) plaque-forming units of MCMV, 7 of 10 NK-depleted mice developed retinitis compared with only 2 of 10 non-NK-depleted control mice. Poly(I-C) activation of NK cells in T cell-depleted animals protected mice from MCMV retinitis; only 2 of 10 mice in the poly(I-C)-treated group developed retinitis compared with 8 of 10 T cell-depleted, non-poly(I-C)-treated control mice. These results show the importance of NK cells in preventing MCMV retinitis and suggest that NK cells may also be involved in modulation of cytomegalovirus retinitis in human patients.

T cells in the uninjected eye after anterior chamber inoculation of herpes simplex virus type 1.

PURPOSE: To investigate T cell infiltration in the posterior segment of the uninjected eye after uniocular anterior chamber inoculation of HSV-1. METHODS: The anterior chamber of one eye of euthymic BALB/c mice was injected with 1 x 10(4) plaque-forming units (PFU) to 2 x 10(4) PFU of herpes simplex virus type 1 (HSV-1; KOS strain). All mice were examined for retinitis on day 8 postinoculation (p.i.). Only mice with retinitis were retained and used in these experiments. Animals were killed on days 9, 11, 14, 21, 35, and 63 p.i. The uninjected eyes were removed. Some of the uninjected eyes were sectioned and stained for CD4+ and CD8+ cells using the avidin-biotinylated enzyme complex method. Infiltrating cells were collected from the remaining uninoculated eyes and stained using rat anti-mouse monoclonal antibodies specific for CD4+ or CD8+ T cells, and the percentage of CD4+ and CD8+ T cells was determined by flow cytometry. RESULTS: At day 9 p.i. (acute retinitis), T cells were observed in the uvea but not in the retina of the contralateral eye. CD4+ and CD8+ cells were observed in the sensory retina coincident with the onset of retinal necrosis (day 11 p.i.), and CD4+ and CD8+ T cells continued to be detected in the remnants of the retina up to and including day 63 p.i. The maximum percentage of both CD4+ and CD8+ T cells was observed at day 21 p.i. CONCLUSIONS: These results demonstrate that T cells enter the retina of the uninoculated eye during HSV-1 infection. The observation that T cells arrive in the sensory retina at the onset of retinal necrosis and not during acute retinitis and the peak of virus replication provides further evidence that T cells play a role in development of retinal necrosis. The result that T cells are observed in the uninjected eye as late as day 63 p.i. suggests that T cells might also have a role in the resolution phase of the disease.