The association between tricuspid regurgitation velocity and 5-year survival in a North West London population of patients with sickle cell disease in the United Kingdom

Raised tricuspid regurgitant velocity (TRV) occurs in approximately 30% of adults with sickle cell disease (SCD), and has been shown to be an independent risk factor for death. TRV was assessed in 164 SCD patients who were subsequently followed up for survival. Raised pulmonary pressures were defined as a TRV jet ≥2.5 m/s on echocardiography. Elevated TRV was present in 29.1% of patients and it was associated with increased age and left atrial diameter. There were 15 deaths (9.1%) over a median of 68.1 months follow up; seven patients had increased TRV, and eight patients had a TRV<2.5 m/s. Higher TRV values were associated with a greater than 4-fold increased risk of death (Hazard Ratio: 4.48, 99% confidence interval 1.01-19.8), although we found a lower overall mortality rate than has been reported in previous studies. TRV was not an independent risk factor for death. We have confirmed the association between raised TRV and mortality in a UK SCD population whose disease severity appears to be less than that reported in previous studies. Further prospective studies are needed to more clearly characterize which patient factors modify survival in SCD patients with raised TRV.

MESAFace, a graphical interface to analyze the MESA output

MESA (Modules for Experiments in Stellar Astrophysics) has become very popular among astrophysicists as a powerful and reliable code to simulate stellar evolution. Analyzing the output data thoroughly may, however, present some challenges and be rather time-consuming. Here we describe MESAFace, a graphical and dynamical interface which provides an intuitive, efficient and quick way to analyze the MESA output.

NATURE OF PROBLEM

Find a way to quickly and thoroughly analyze the output of a MESA run, including all the profiles, and have an efficient method to produce graphical representations of the data.

SOLUTION METHOD

We created two scripts (to be run consecutively). The first one downloads all the data from a MESA run and organizes the profiles in order of age. All the files are saved as tables or arrays of tables which can then be accessed very quickly by Mathematica. The second script uses the Manipulate function to create a graphical interface which allows the user to choose what to plot from a set of menus and buttons. The information shown is updated in real time. The user can access very quickly all the data from the run under examination and visualize it with plots and tables.

UNUSUAL FEATURES

Moving the slides in certain regions may cause an error message. This happens when Mathematica is asked to read nonexistent data. The error message, however, disappears when the slides are moved back. This issue does not preclude the good functioning of the interface.

ADDITIONAL COMMENTS

The program uses the dynamical capabilities of Mathematica. When the program is opened, Mathematica prompts the user to "Enable Dynamics". It is necessary to accept before proceeding.

RUNNING TIME

Depends on the size of the data downloaded, on where the data are stored (hard-drive or web), and on the speed of the computer or network connection. In general, downloading the data may take from a minute to several minutes. Loading directly from the web is slower. For example, downloading a 200MB data folder (a total of 102 files) with a dual-core Intel laptop, P8700, 2 GB of RAM, at 2.53 GHz took about a minute from the hard-drive and about 23 minutes from the web (with a basic home wireless connection).

Morpho-Physiological and Biochemical Criteria of Acanthamoeba spp. Isolated from the Egyptian Aquatic Environment

BACKGROUND

The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed.

METHODS

Some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acanthamoeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis.

RESULTS

Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-pathogenic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba.

CONCLUSION

The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified.

Prophylactic vaccine approach for colon and pancreatic cancers: present and future

Vaccines against cancers have not been as effective as vaccines against infectious diseases. However, recent studies have advanced our understanding of the stages of tumor cell development and of mechanisms of immune surveillance, immune suppression, and of tumor escape from the immune system. The development of animal models that mimic development of human cancers has helped advance the understanding of these processes and is aiding the development of greatly improved vaccines. Here we review the recent progress in developing vaccines and prophylactic approaches for pancreatic and colon cancers. Improved understanding of the expression of various oncogenes and tumor-associated antigens helps in selecting antigenic targets for stage-specific immune prevention. Identification of the earliest alterations in precancerous lesions and selection of epitopes unique to the aberrant cells and capable of triggering strong cytotoxic and helper T cell responses may aid the development of safe and effective vaccines for use in those at high risk of progressing to invasive cancers. The responses can be enhanced with carefully selected adjuvants to boost immunity and by selecting epitopes that are expressed on dendritic cells, thereby promoting T cell responses. Tumor resistance via loss of the targeted antigen can be mitigated by inclusion of multiple tumor epitopes in vaccine constructs. Tumor immune escape can be diminished by targeting various immunosuppressive mechanisms used by different tumors, such as tumor production of immunosuppressive cytokines (e.g., interleukin 10, and Transforming Growth Factor-beta, which can promote activity of immunosuppressive regulatory T cells), or by inhibiting production of inflammatory prostanoids with combined cyclooxygenase/lipoxygenase inhibitors. Finally, prevention of many cancers may be enhanced by carefully selecting and scheduling of vaccine administration in combination with other chemotherapeutic or chemopreventive agents. Preclinical and early clinical trials incorporating these principles are discussed.

Does use of a World Health Organization obstetric safe surgery checklist improve communication between obstetricians and anaesthetists? A retrospective study of 389 caesarean sections

We evaluated the impact of the World Health Organization Obstetric Safe Surgery Checklist (WHO Checklist) on perioperative communication between anaesthetists and obstetricians by performing a retrospective audit in a Teaching hospital in London, UK. Caesarean section births from February to March 2009 and April to May 2011 were studied. Caesarean section notes from obstetricians and anaesthetists managing the same woman during the study period were reviewed. Grading differences between obstetricians and anaesthetists before and after checklist introduction were evaluated. Communication failure (where obstetricians and anaesthetists had documented different caesarean section grades [level of urgency]) and good communication (where obstetricians and anaesthetists had documented the same caesarean section grade) were observed. In total, 195 caesarean sections before introduction of the WHO safe surgery checklist and 194 caesarean sections after checklist introduction were studied. Grading differences occurred in 24.1% of caesarean sections without checklists compared with 10.3% with checklists (P < 0.001). During emergency caesarean section alone, grading differences between obstetricians and anaesthetists were smaller, although this was not significant (P = 0.222). We conclude that implementation of a WHO Obstetric Safe Surgery checklist improves the communication of caesarean section grade (urgency) between obstetricians and anaesthetists.

Cumulative exposure to gamma interferon-dependent chemokines CXCL9 and CXCL10 correlates with worse outcome after lung transplant

Outcomes following lung transplant are suboptimal owing to chronic allograft failure termed bronchiolitis obliterans syndrome (BOS). Prior work in both mice and humans has shown that interferon gamma (IFNG)-induced chemokines, including CXCL9 and CXCL10, are elevated in patients with established BOS. We hypothesized that patients who ultimately developed BOS would have elevations in these chemokines before losing lung function. We utilized a high throughput multiplex enzyme-linked immunosorbent assay (ELISA) to measure biomarkers in bronchoalveolar lavage fluid (BALF). We modeled cumulative exposure to seven biomarkers (CXCL9, CXCL10, RANTES, IL1-RA, IL-17, MCP1 and IL-13) by calculating the 1-year area under the curve (AUC) for each biomarker in the BALF of 40 lung transplant patients who had at least four samples obtained in the first year posttransplant. Cumulative elevations in CXCL9 and CXCL10 were associated with a significant risk of subsequent graft failure after transplant (HR 9.37 and 5.52, respectively; p < 0.01 for both). Further these chemokines were also elevated in patients before the onset of BOS. CXCL9 and CXCL10 elevations were seen between 3 and 9 months before graft failure. Our data show that persistent presence of CXCL9 and CXCL10 portents worsening lung allograft function; measuring these IFNG-induced chemokines might prospectively identify patients at risk for BOS.

Angiosarcoma of the small intestine

Primary gastrointestinal angiosarcomas are very rare and those of the small bowel even more rare. We report a case which is the first in the literature from this part of the world. It presented in a 25-year-old woman with multiple dissemination and rapid fatality. Diagnosis was based on histological morphology using Hematoxylin and Eosin (H and E) stains, plus reticulin special stain to outline the vascular nature.

Inflammatory bowel disease in Nigerians: still a rare diagnosis?

Inflammatory bowel disease (IBD) has been thought to have a low incidence among subSaharan Africans mainly because of the sporadic cases reported from the continent in comparison with the larger numbers reported from North America and Western European countries. Is this difference based on real demographic susceptibilities or a reflection of lower level of healthcare delivery? Three cases of ulcerative colitis and one case of Crohn's disease diagnosed in a tertiary institution in northern Nigeria in the span of three years are reported. Their presentation coincided with the creation of the Gastrointestinal Surgery Unit of our hospital and with it the availability of endoscopic diagnostic procedures. All four patients were indigenous Nigerians. Our findings suggest that IBD may be more common in this part of the world than previously thought. With an increased awareness of the disease in our population, a greater utilization of modern medicine as against alternative medicine and with wider availability of diagnostic tools in our hospitals, it is our guess that more cases may be found in the future to dispel the belief that Africans are somewhat immune to this affliction.

A randomised study of peri-prosthetic bone density after cemented versus trabecular fixation of a polyethylene acetabular component

The ideal acetabular component is characterised by reliable, long-term fixation with physiological loading of bone and a low rate of wear. Trabecular metal is a porous construct of tantalum which promotes bony ingrowth, has a modulus of elasticity similar to that of cancellous bone, and should be an excellent material for fixation. Between 2004 and 2006, 55 patients were randomised to receive either a cemented polyethylene or a monobloc trabecular metal acetabular component with a polyethylene articular surface. We measured the peri-prosthetic bone density around the acetabular components for up to two years using dual-energy x-ray absorptiometry. We found evidence that the cemented acetabular component loaded the acetabular bone centromedially whereas the trabecular metal monobloc loaded the lateral rim and behaved like a hemispherical rigid metal component with regard to loading of the acetabular bone. We suspect that this was due to the peripheral titanium rim used for the mechanism of insertion.

A single episode of haematospermia can be safely managed in the community

INTRODUCTION

This study is a ten-year single institution retrospective study of patients presenting with haematospermia, to establish standard tests for investigation, and what tests have low yield and can be omitted.

MATERIALS AND METHODS

Investigations that were used were analysed to establish their diagnostic yield. The parameters examined were: digital rectal examination (DRE) findings, prostate specific antigen (PSA), abdominal and scrotal ultrasound, TRUS biopsy result (wherever applicable), flexible cystoscopy findings and final diagnosis.

RESULTS

The central findings were that abdominal ultrasound never yielded an abnormality and that flexible cystoscopy never showed bladder tumours. TRUS prostate biopsies were performed in 17% of patients, and prostate cancer was confirmed in 5% of patients. Testicular malignancy was found in 2%. In 90% of patients, no specific diagnosis was made, and 85% of patients were discharged at review.

CONCLUSIONS

A single episode of haematospermia is usually benign. Flexible cystoscopy and abdominal ultrasound appear valueless. Assessment should consist of clinical examination (including testicular), DRE and PSA testing. It can safely be managed in the community and only referred in the presence of, abnormal examination, elevated PSA or recurrent symptoms.

Electrocautery of the patellar rim in primary total knee replacement: beneficial or unnecessary?

The management of the patella during total knee replacement is controversial. In some studies the absence of patellar resurfacing results in residual anterior knee pain in over 10% of patients. One form of treatment which may be used in an endeavour to reduce this is circumferential patellar rim electrocautery. This is believed to partially denervate the patella. However, there is no evidence of the efficacy of this procedure, nor do we know if it results in harm.

A retrospective comparative cohort study was performed of 192 patients who had undergone a primary total knee replacement with the porous coated Low Contact Stress rotating platform prosthesis without patellar resurfacing between 2003 and 2007. In 98 patients circumferential electrocautery of the patellar rim was performed and in 94 patients it was not. The two groups were matched for gender and age. The general Oxford Knee Score and the more specific patellar score for anterior knee pain were used to assess patient outcomes a minimum of two years post-operatively.

No statistically significant differences were noted between the groups for either scoring system (p = 0.41 and p = 0.87, respectively). Electrocautery of the patella rim did not improve the outcome scores after primary total knee replacement in our patients.