BioMed Central - Latest Articles

Urachal tumour: case report of a poorly understood carcinoma

Stefano Scabini — 2009-11-07T00:00:00Z

Background: Urachal carcinoma is an uncommon neoplasm associated with poor prognosis.Case presentationA 45-year-old man was admitted with complaints of abdominal pain and pollakisuria. A soft mass was palpable under his navel. TC-scan revealed a 11 x 6 cm tumor, which was composed of a cystic lesion arising from the urachus and a solid mass component at the urinary bladder dome. The tumor was removed surgically. Histological examination detected poor-differentiated adenocarcinoma, which had invaded the urinary bladder. The patient has been followed up without recurrence for 6 months. Conclusions: The urachus is the embryological remnant of urogenital sinus and allantois. Involution usually happens before birth and urachus is present as a median umbilical ligament. The pathogenesis of urachal tumours is not fully understood. Surgery is the treatment of choice and role of adjuvant treatment is not clearly understood.

Risk factors for tuberculosis in dialysis patients: a prospective multicenter clinical trial

Antonios Christopoulos — 2009-11-07T00:00:00Z

Background: Profound alterations in immune responses associated with uraemia and exacerbated by dialysis increase the risk of developing active tuberculosis (TB) in chronic haemodialysis patients (HDPs). In the current study, was determined the impact of various risk factors on TB development. Our aim was to identify which HDPs need anti-TB preventive therapy. Methods: Prospective study of 272 HDPs admitted, through a 36-month period, to our institutions. Specific Relative Risk (RR) for TB was estimated, considering age matched subjects from the general population as reference group. Entering the study all patients were tested with tuberculin (TST). Using Cox's proportional hazard model the independent effect of various risk factors associated with TB development was estimated. Results: History of TB, dialysis efficiency, use of Vitamin D supplements, serum albumin and zinc levels were not proved to influence significantly the risk for TB, in contrast to: advanced age (>65 years), BMI, diabetes mellitus, tuberculin reactivity, healed TB lesions on chest X-ray and time on dialysis. Elderly (>70 years old) HDPs (Adjusted RR 25.3, 95%CI 20.4-28.4, P<0.02), diabetics (Adj.RR 25.3, 95%CI 17.2-21.1, P<0.03), underweighted (Adj.RR 72.3, 95%CI 65.2-79.8 P<0.001), tuberculin responders (Adj.RR 41.4, 95%CI 37.9-44.8, P<0.03), HDPs with fibrotic lesions on chest x-ray (Adj.RR 82.3, 95%CI 51.3-95.5, P<0.03) and those treated with haemodialysis for < 12 months (Adj.RR 110.0, 95%CI 97.4-135.3, P<0.001), presented significantly higher specific RR for TB even after adjusting for the effect of the remaining studied risk factors. Conclusion: The above mentioned factors have to be considered by the clinicians, evaluating for TB in HDPs. Positive TST, the existence of predisposing risk factors and/or old TB lesions on chest X-ray, will guide the diagnosis of latent TB infection and the selection of those HDPs who need preventive chemoprophylaxis.

Repair of injured right inferior pulmonary vein during mitral valve replacement

Efstratios Apostolakis — 2009-11-07T00:00:00Z

During mitral valve surgery right pulmonary veins injury, subsequent to excessive traction (for better exposure of the mitral apparatus), is often unavoidable. This is more likely in patients with small left atrium. This common complication may cause severe intraoperative bleeding, while its surgical repair may lead to complications such as late stenosis or obstruction of the pulmonary veins. This injury should be early detected, before left atriotomy closing, and it is suggested to be repaired using a patch so as to avoid any possible late constriction.We describe a case -to our knowledge, the first reported in the literature- of intraoperatively injured right inferior pulmonary vein in a patient who underwent mitral valve replacement. As outlined we propose that the ostium of the right inferior pulmonary vein can be repaired by using autologous pericardial patch, incorporated in the completion of left atriotomy closure.

Use of endobronchial one-way valves reveals questions on etiology of spontaneous pneumothorax: report of three cases

Wai Cho Yu — 2009-11-07T00:00:00Z

Spontaneous pneumothoraces are believed to arise when air from the supplying airway exit via a ruptured visceral pleural bleb into the pleural cavity. Endobronchial one-way valves (EBVs) allow air exit (but not entry) from individual segmental airways. Systematic deployment of EBVs was applied to three patients with secondary spontaneous pneumothoraces and persistent airleak. In all cases, balloon-catheter occlusion of the upper lobe bronchus stopped the airleak. EBVs applied to individual upper lobe segmental airways failed to terminate the airleak, which only stopped after placements of multiple EBVs to occlude all upper lobe segments. The observation questions the traditional belief of 'one-airway-one-bleb-one-leak' in spontaneous pneumothorax.

Francisella tularensis subsp. novicida isolated from a human in Arizona

Dawn Birdsell — 2009-11-06T00:00:00Z

Background: Francisella tularensis is the etiologic agent of tularemia and is classified as a select agent by the Centers for Disease Control and Prevention. Currently four known subspecies of F. tularensis that differ in virulence and geographical distribution are recognized: tularensis (type A), holarctica (type B), mediasiatica, and novicida. Because of the Select Agent status and differences in virulence and geographical location, the molecular analysis of any clinical case of tularemia is of particular interest. We analyzed an unusual Francisella clinical isolate from a human infection in Arizona using multiple DNA-based approaches. Results: We report that the isolate is F. tularensis subsp. novicida, a subspecies that is rarely isolated. Conclusion: The rarity of this novicida subspecies in clinical settings makes each case study important for our understanding of its role in disease and its genetic relationship with other F. tularensis subspecies.

Does physical activity change predict functional recovery in low back pain? Protocol for a prospective cohort study

Paul Hendrick — 2009-11-06T00:00:00Z

Background: Activity advice and prescription are commonly used in the management of low back pain (LBP). Although there is evidence for advising patients with LBP to remain active, facilitating both recovery and return to work, to date no research has assessed whether objective measurements of free living physical activity (PA) can predict outcome, recovery and course of LBP. Methods: An observational longitudinal study will investigate PA levels in a cohort of community-dwelling working age adults with acute and sub-acute LBP. Each participant's PA level, functional status, mood, fear avoidance behaviours, and levels of pain, psychological distress and occupational activity will be measured on three occasions during for 1 week periods at baseline, 3 months, and 1 year. Physical activity levels will be measured by self report, RT3 triaxial accelerometer, and activity recall questionnaires. The primary outcome measure of functional recovery will be the Roland Morris Disability Questionnaire (RMDQ). Free living PA levels and changes in functional status will be quantified in order to look at predictive relationships between levels and changes in free living PA and functional recovery in a LBP population.DiscussionThis research will investigate levels and changes in activity levels of an acute LBP cohort and the predictive relationship to LBP recovery. The results will assess whether occupational, psychological and behavioural factors affect the relationship between free living PA and LBP recovery. Results from this research will help to determine the strength of evidence supporting international guidelines that recommend restoration of normal activity in managing LBP.Trial registration: [Clinical Trial Registration Number, ACTRN12609000282280]

Vascular endothelial growth factor - prognostic factor in children with neuroblastoma: a retrospective analysis

Gordana Jakovljevic — 2009-11-06T00:00:00Z

Background: Despite aggressive therapy, advanced stage neuroblastoma patients have poor survival rates. Although angiogenesis correlates with advanced tumour stage and plays an important role in determining the tumour response to treatment in general, clinical data are still insufficient, and more clinical evaluations are needed to draw conclusions. The aim of this study was to evaluate vascular endothelial growth factor (VEGF) expression in patients with neuroblastoma, determine whether it correlates with other prognostic factors and/or therapeutic response, and to assess should VEGF be considered in a routine diagnostic workup. Materials and Methods: VEGF expression was determined by immunohistochemistry using anti-VEGF antibody in paraffin embedded primary tumour tissue from 56 neuroblastoma patients. Semiquantitative expression of VEGF was estimated and compared with gender, age, histology, disease stage, therapy, and survival. Statistical analyses, including multivariate analysis, were performed. Results: VEGF expression correlated with disease stage and survival in neuroblastoma patients. Combination of VEGF expression and disease stage as a single prognostic value for survival (P-value = 0.0034; odds ratio (OR) (95%CI) = 26.17 (2.97-230.27) exhibited greater correlation with survival than individually. Hematopoietic stem cell transplantation significantly improved survival of the advanced stage patients with high VEGF expression. Conclusions: VEGF expression should be considered in a routine diagnostic workup of children with neuroblastoma, especially in those more than 18 months old and with advanced disease stage. High VEGF expression at the time of disease diagnosis is a bad risk prognostic factor, and can be used to characterize subsets of patients with an unfavourable outcome.

Bioinformatic evidence for a stem-loop structure 5'-adjacent to the IGR-IRES and for an overlapping gene in the bee paralysis dicistroviruses

Andrew Firth — 2009-11-06T00:00:00Z

The family Dicistroviridae (order Picornavirales) includes species that infect insects and other arthropods. These viruses have a linear positive-sense ssRNA genome of ~8-10 kb, which contains two long ORFs. The 5' ORF encodes the nonstructural polyprotein while the 3' ORF encodes the structural polyprotein. The dicistroviruses are noteworthy for the intergenic Internal Ribosome Entry Site (IGR-IRES) that mediates efficient translation initation on the 3' ORF without the requirement for initiator Met-tRNA. Acute bee paralysis virus, Israel acute paralysis virus of bees and Kashmir bee virus form a distinct subgroup within the Dicistroviridae family. In this brief report, we describe the bioinformatic discovery of a new, apparently coding, ORF in these viruses. The ORF overlaps the 5' end of the structural polyprotein coding sequence in the +1 reading frame. We also identify a potential 14-18 bp RNA stem-loop structure 5'-adjacent to the IGR-IRES. We discuss potential translation initiation mechanisms for the novel ORF in the context of the IGR-IRES and 5'-adjacent stem-loop.

Elucidation of functional consequences of signalling pathway interactions

Adaoha Ihekwaba — 2009-11-06T00:00:00Z

Background: A great deal of data has accumulated on signalling pathways. These large datasets are thought to contain much implicit information on their molecular structure, interaction and activity information; which provides a picture of intricate molecular networks believed to underlie biological functions. While tremendous advances have been made in trying to understand these systems, how information is transmitted within them is still poorly understood. This ever growing amount of data demands we adopt powerful computational techniques that will play a pivotal role in the conversion of mined data to knowledge, and in elucidating the topological and functional properties of protein-protein interactions. Results: A computational framework is presented which allows for the description of embedded networks, and identification of common components thought to assist in the transmission of information within the systems studied. By employing the graph theories of network biology - such as degree distribution, clustering coefficient, vertex betweenness and shortest path measures - topological features of protein-protein interactions for published datasets of the p53, nuclear factor kappa B and G1/S phase of the cell cycle systems were ascertained. Highly ranked nodes which in some cases acted as connecting proteins most likely responsible for propagation of transduction signals across the networks were identified. The functional consequences of these nodes in the context of their network environment were also determined. These findings highlight the usefulness of the framework in identifying possible combination or links within these systems as targets for therapeutic responses; and put forward the idea of using retrieved knowledge on the shared components in constructing better organised and structured models of signalling networks. Conclusion: It is hoped that through the data mined reconstructed signal transduction networks, well developed models of the published data can be built which in the end would guide the prediction of new targets based on the pathway's environment for further analysis. Source code is available upon request.

Management of severe crush injury in a front-line tent ICU after the 2008 Wenchuan earthquake in China: an experience with 32 cases

Wenfang Li — 2009-11-06T00:00:00Z

IntroductionThe experience on management of crush injury after a devastating earthquake is lacking, and there are even less reports on the front-line critical care of these patients. A front-line intensive care unit (ICU) was set up in a tent after the disastrous Wenchuan earthquake (May, 12, 2008, China), where 32 patients suffering from crush injury were treated from May 12 to May 26. This study summarized our experience on management of 32 crush injury patients in a front-line tent ICU. Methods: We retrospectively analyzed the clinical data of 32 crush injury patients treated in our frontline tent ICU. Using limited equipment, we observed the arterial blood gas parameters, blood routine, alanine aminotransferase, lactate dehydrogenase, creatine kinase, creatinine, blood urea nitrogen, and urine protein of patients. We also closely watched for changes in crush injury symptoms, urine output, and the dangerous complications of crush injury. Results: Eighteen of the 32 patients developed traumatic shock, 9 had acute renal failure, 6 had acute heart failure, 2 had stress ulcers and 4 had multiple organ dysfunction syndrome (MODS). The symptoms of 17 patients met the criteria of crush syndrome; hemodialysis and prompt surgical intervention were given to them when necessary. Prompt treatment in our tent ICU improved the symptoms of patients to different degrees. The limb distension and sensory dysfunction were improved and the urine output was increased or even restored to the normal level in some patients. Serological parameters were improved in most patients after admission. Five (15.63%) patients underwent amputation due to severe infection in our group. Six (18.75%) patients died, 4 due to MODS and 2 due to acute renal failure. Conclusions: Severe crushing injuries and life-threatening complications are major causes of death after major disasters like earthquakes. Prompt treatment and close monitoring of the severe complications are of great importance in saving patients' lives. Establishment of a well-equipped front-line ICU close to the epicentre of the earthquake allows for prompt on the spot rescue of critical patients with crush injury, greatly decreasing the mortality rate and complications and avoiding amputation. There should be sufficient equipment to meet the needs of more patients.