bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular modeling and in silico characterization of Mycobacterium tuberculosis TlyA: Possible misannotation of this tubercle bacilli-hemolysin
Authors: Arenas Nelson E , Salazar Luz M , Soto Carlos Y , Vizcaíno Carolina , Patarroyo Manuel E , Patarroyo Manuel A , Gómez Arley
Published: April 2011

Background

The TlyA protein has a controversial function as a virulence factor in Mycobacterium tuberculosis (M. tuberculosis). At present, its dual activity as hemolysin and RNA methyltransferase in M. tuberculosis has been indirectly proposed based on in vitro results. There is no evidence however for TlyA relevance in the survival of tubercle bacilli inside host cells or whether both activities are functionally linked. A thorough analysis of structure prediction for this mycobacterial protein in this study shows the need for reevaluating TlyA's function in virulence.

Results

Bioinformatics analysis of TlyA identified a ribosomal protein binding domain (S4 domain), located between residues 5 and 68 as well as an FtsJ-like methyltranferase domain encompassing residues 62 and 247, all of which have been previously described in translation machinery-associated proteins. Subcellular localization prediction showed that TlyA lacks a signal peptide and its hydrophobicity profile showed no evidence of transmembrane helices. These findings suggested that it may not be attached to the membrane, which is consistent with a cytoplasmic localization. Three-dimensional modeling of TlyA showed a consensus structure, having a common core formed by a six-stranded β-sheet between two α-helix layers, which is consistent with an RNA methyltransferase structure. Phylogenetic analyses showed high conservation of the tlyA gene among Mycobacterium species. Additionally, the nucleotide substitution rates suggested purifying selection during tlyA gene evolution and the absence of a common ancestor between TlyA proteins and bacterial pore-forming proteins.

Conclusion

Altogether, our manual in silico curation suggested that TlyA is involved in ribosomal biogenesis and that there is a functional annotation error regarding this protein family in several microbial and plant genomes, including the M. tuberculosis genome.
Respirator fit of a medium mask on a group of South Africans: a cross-sectional study
Authors: Spies Adri , Wilson Kerry S , Ferrie Robert
Published: April 2011

Background

In South Africa, respiratory protective equipment is often the primary control method used to protect workers. This preliminary study investigated how well a common disposable P2 respirator fitted persons with a range of facial dimensions.

Methods

Quantitative respirator fit tests were performed on 29 volunteers from different racial, gender and face size groups. Two facial dimensions width (bizygomatic) and length (menton-sellion) were measured for all participants.

Results

In this study 13.8% of the participants demonstrated a successful fit with the medium sized mask. These included participants from three different racial and both gender groups. The large percentage of failed fit tests (86%) indicates that reliance on off-the-shelf respirators could be problematic in South Africa.

Conclusions

The limitations of this preliminary study notwithstanding, respirator fit appear to be associated with individual facial characteristics and are not specific to racial/ethnic or gender characteristics.
Singlet oxygen mediated DNA degradation by copper nanoparticles: potential towards cytotoxic effect on cancer cells
Authors: Jose Gregor P , Santra Subhankar , Mandal Swadhin K , Sengupta Tapas K
Published: April 2011

The DNA degradation potential and anti-cancer activities of copper nanoparticles of 4-5 nm size are reported. A dose dependent degradation of isolated DNA molecules by copper nanoparticles through generation of singlet oxygen was observed. Singlet oxygen scavengers such as sodium azide and Tris [hydroxyl methyl] amino methane were able to prevent the DNA degradation action of copper nanoparticles confirming the involvement of activated oxygen species in the degradation process. Additionally, it was observed that the copper nanoparticles are able to exert cytotoxic effect towards U937 and Hela cells of human histiocytic lymphoma and human cervical cancer origins, respectively by inducing apoptosis. The growth characteristics of U937 and Hela cells were studied applying various concentrations of the copper nanoparticles.
Novel docetaxel-loaded nanoparticles based on poly(lactide-co-caprolactone) and poly(lactide-co-glycolide-co-caprolactone) for prostate cancer treatment: formulation, characterization, and cytotoxicity studies
Authors: Sanna Vanna , Roggio Anna Maria , Posadino Anna Maria , Cossu Annalisa , Marceddu Salvatore , Mariani Alberto , Alzari Valeria , Uzzau Sergio , Pintus Gianfranco , Sechi Mario
Published: April 2011

Docetaxel (Dtx) chemotherapy is the optional treatment in patients with hormone-refractory metastatic prostate cancer, and Dtx-loaded polymeric nanoparticles (NPs) have the potential to induce durable clinical responses. However, alternative formulations are needed to overcome the serious side effects, also due to the adjuvant used, and to improve the clinical efficacy of the drug.

In the present study, two novel biodegradable block-copolymers, poly(lactide-co-caprolactone) (PLA-PCL) and poly(lactide-co-caprolactone-co-glycolide) (PLGA-PCL), were explored for the formulation of Dtx-loaded NPs and compared with PLA- and PLGA-NPs. The nanosystems were prepared by an original nanoprecipitation method, using Pluronic F-127 as surfactant agent, and were characterized in terms of morphology, size distribution, encapsulation efficiency, crystalline structure, and in vitro release. To evaluate the potential anticancer efficacy of a nanoparticulate system, in vitro cytotoxicity studies on human prostate cancer cell line (PC3) were carried out. NPs were found to be of spherical shape with an average diameter in the range of 100 to 200 nm and a unimodal particle size distribution. Dtx was incorporated into the PLGA-PCL NPs with higher (p < 0.05) encapsulation efficiency than that of other polymers. Differential scanning calorimetry suggested that Dtx was molecularly dispersed in the polymeric matrices. In vitro drug release study showed that release profiles of Dtx varied on the bases of characteristics of polymers used for formulation. PLA-PCL and PLGA-PCL drug loaded NPs shared an overlapping release profiles, and are able to release about 90% of drug within 6 h, when compared with PLA- and PLGA-NPs. Moreover, cytotoxicity studies demonstrated advantages of the Dtx-loaded PLGA-PCL NPs over pure Dtx in both time- and concentration-dependent manner. In particular, an increase of 20% of PC3 growth inhibition was determined by PLGA-PCL NPs with respect to free drug after 72 h incubation and at all tested Dtx concentration. In summary, PLGA-PCL copolymer may be considered as an attractive and promising polymeric material for the formulation of Dtx NPs as delivery system for prostate cancer treatment, and can also be pursued as a validated system in a more large context.
Development of a blood-based gene expression algorithm for assessment of obstructive coronary artery disease in non-diabetic patients
Authors: Elashoff Michael R , Wingrove James A , Beineke Philip , Daniels Susan E , Tingley Whittemore G , Rosenberg Steven , Voros Szilard , Kraus William E , Ginsburg Geoffrey S , Schwartz Robert S , Ellis Stephen G , Tahirkheli Naheem , Waksman Ron , McPherson John , Lansky Alexandra J , Topol Eric J
Published: April 2011

Background

Alterations in gene expression in peripheral blood cells have been shown to be sensitive to the presence and extent of coronary artery disease (CAD). A non-invasive blood test that could reliably assess obstructive CAD likelihood would have diagnostic utility.

Results

Microarray analysis of RNA samples from a 195 patient Duke CATHGEN registry case:control cohort yielded 2,438 genes with significant CAD association (p < 0.05), and identified the clinical/demographic factors with the largest effects on gene expression as age, sex, and diabetic status. RT-PCR analysis of 88 CAD classifier genes confirmed that diabetic status was the largest clinical factor affecting CAD associated gene expression changes. A second microarray cohort analysis limited to non-diabetics from the multi-center PREDICT study (198 patients; 99 case: control pairs matched for age and sex) evaluated gene expression, clinical, and cell population predictors of CAD and yielded 5,935 CAD genes (p < 0.05) with an intersection of 655 genes with the CATHGEN results. Biological pathway (gene ontology and literature) and statistical analyses (hierarchical clustering and logistic regression) were used in combination to select 113 genes for RT-PCR analysis including CAD classifiers, cell-type specific markers, and normalization genes.

RT-PCR analysis of these 113 genes in a PREDICT cohort of 640 non-diabetic subject samples was used for algorithm development. Gene expression correlations identified clusters of CAD classifier genes which were reduced to meta-genes using LASSO. The final classifier for assessment of obstructive CAD was derived by Ridge Regression and contained sex-specific age functions and 6 meta-gene terms, comprising 23 genes. This algorithm showed a cross-validated estimated AUC = 0.77 (95% CI 0.73-0.81) in ROC analysis.

Conclusions

We have developed a whole blood classifier based on gene expression, age and sex for the assessment of obstructive CAD in non-diabetic patients from a combination of microarray and RT-PCR data derived from studies of patients clinically indicated for invasive angiography.

Clinical trial registration information

PREDICT,PersonalizedRiskEvaluation andDiagnosisin theCoronaryTree,http://www.clinicaltrials.gov,NCT00500617
Characteristics of non‐AIDS‐defining malignancies in the HAART era: a clinico‐epidemiological study
Authors: Dauby Nicolas , De Wit Stéphane , Delforge Marc , Necsoi Valentina Coca , Clumeck Nathan
Published: April 2011

Background

Non‐AIDS‐defining malignancies (NADM) are becoming a major cause of mortality in the era of highly active antiretroviral therapy. We wished to investigate the incidence, risks factors and outcome of NADM in an urban cohort.

Methods

We carried out an observational cohort of HIV patients with 12,746 patient‐years of follow up between January 2002 and March 2009. Socio‐demographics and clinical characteristics of patients diagnosed with NADM were retrospectively compared with the rest of the cohort. Causes of death and risk factors associated with NADM were assessed using logistic regression. Survival analyses were performed with Kaplan‐Meier estimates. Cancer incidences were compared with those of the general population of the Brussels‐Capital Region using the standardized incidence ratio (SIR).

Results

Forty‐five NADM were diagnosed. At inclusion in the study, patients with NADM were older than patients without NADM (47 years vs. 38 years, p < 0.001), had a longer history of HIV infection (59 months vs. 39 months, p = 0.0174), a lower nadir CD4 count (110 cells/mm3 vs. 224 cells/mm3, p < 0.0001) and a higher rate of previous AIDS events (33% vs. 20%, p = 0.0455) and of hepatitis C virus co‐infection (22.2% vs. 10%, p = 0.0149). In multivariate analysis, age over 45 at baseline (OR 3.25; 95% CI 1.70‐6.22) and a nadir CD4 count of less than 200 cells/mm3 (OR 3.10; 95% CI 1.40‐6.87) were associated with NADM. NADM were independently associated with higher mortality in the cohort (OR 14.79; 95% CI 6.95‐31.49). Women with cancer, the majority of whom were of sub‐Saharan African origin, had poorer survival compared with men. The SIR for both sexes were higher than expected for Hodgkin's lymphoma (17.78; 95% CI 6.49‐38.71), liver cancers (8.73; 95% CI 2.35‐22.34), anal cancers (22.67; 95% CI 8.28‐49.34) and bladder cancers (3.79; 95% CI 1.02‐9.70). The SIR for breast cancer was lower in women (SIR 0.29; 95% CI 0.06‐0.85).

Conclusions

Age over 45 and a nadir CD4 count of less than 200 cells/mm3 were predictive of NADM in our cohort. Mortality was high, especially in sub‐Saharan African women. Cancers with increased incidences were Hodgkin's lymphoma and anal, bladder and liver cancers in both sexes; women had a lower incidence of breast cancer.
Editorial: Hijacking the IL-7/IL-7R system in HIV infection
Authors: Paiardini Mirko
Published: March 2011

The IL-7/IL-7R pathway is activated during HIV-induced lymphopenia, but its function is limited by reduced responsiveness to IL-7.
Experience of stigma by people with schizophrenia compared with people with depression or malignancies
Authors: Świtaj Piotr , Wciórka Jacek , Grygiel Paweł , Smolarska-Świtaj Julita , Anczewska Marta , Grzesik Artur
Published: March 2011

Aims and method

To compare the frequency of experiences of stigma reported by people with schizophrenia and by people with other health problems (depression and malignancies). The Stigma section of the Consumer Experiences of Stigma Questionnaire (CESQ) was administered to 153 people with schizophrenia, 106 people with depression and 85 people with malignancies.

Results

Using multiple regression analysis we showed that after controlling for the differences in the participants' background characteristics, people with depression did not differ significantly in terms of the frequency of self-reported stigma experiences from patients with schizophrenia (β = − 0.064, P < 0.05). However, patients with malignancies felt stigmatised significantly less often than patients with schizophrenia β= − 0.240, P < 0.05).

Clinical implications

Our findings confirm that the stigma of mental illness is more pronounced than the stigma associated with physical health problems. Contrary to expectations, however, we were not able to demonstrate that people with depression are treated more favourably and experience less stigma than people with schizophrenia.
Comparison of emotional intelligence between psychiatrists and surgeons
Authors: Stanton Clive , Sethi Faisil Nasim , Dale Oliver , Phelan Michael , Laban James Theodore , Eliahoo Joseph
Published: March 2011

Aims and method

A comparative analysis of emotional intelligence between psychiatrists and surgeons using the Bar-On Emotional Quotient Inventory (Bar-On EQ-i) validated assessment tool. Applied to psychiatrists and surgeons with postgraduate membership in Greater London.

Results

A total of 148 individuals were recruited. The median scores for Total EQ scores were average, with no difference in Total EQ between psychiatrists and surgeons (P = 0.872). Psychiatrists scored significantly higher in the subscales of emotional self-awareness (P = 0.002), empathy (P = 0.005), social responsibility (P = 0.04) and impulse control (P = 0.011). Surgeons scored significantly higher in the subscales of self-regard (P = 0.005), stress tolerance (P < 0.0001) and optimism (P = 0.009).

Clinical implications

There are significant differences between psychiatrists and surgeons in the component factors that make up the Total EQ score. They seemingly correspond with widely held perceptions.
Psychiatry and politicians: the ‘hubris syndrome’
Authors: Russell Gerald
Published: March 2011

Lord Owen has alerted us to the dangers of ill health in heads of government, especially if they strive to keep their illnesses secret. The description of the hubris syndrome is still at an early stage but Owen has provided psychiatrists and other physicians with useful guidance on how to recognise its appearance in persons who hold positions of power. He has also provided advice to doctors caring for such persons.
Continuing professional development for psychiatrists: surveying current practice in the UK
Authors: Bamrah J. S. , Gray D. A. , Purandare N. , Merve S.
Published: March 2011

Aims and method

The Royal College of Psychiatrists recommends that all psychiatrists undertake continuing professional development (CPD) as part of their personal development plan (PDP) and that, for quality assurance, all CPD activity is approved by their peer groups. We conducted a regional survey (Survey I) of consultant psychiatrists attending a regional conference of the College to assess their current CPD practice, and a more detailed national survey (Survey II) into sessional time for CPD and peer group activity of all consultant psychiatrists and staff grade, associate specialist and specialty (SASS) doctors.

Results

The surveys showed some similarities. Survey I (n = 36) showed that 83% of consultants had a current CPD certificate and that consultants experienced significantly more difficulty in achieving their ‘internal’ compared with ‘external’ CPD requirements (39% v. 20%). Survey II (n = 2632) showed that 98% of our sample thought CPD was important for revalidation. Despite this, over 50% had difficulty accessing CPD time regularly in their timetable. In total, 97.4% of consultants and 85.7% of SASS doctors were in peer groups.

Clinical implications

A revised CPD policy must give credit to peer group meetings and set out more clearly the distinction between the types of CPD activity psychiatrists undertake. We recommend more robust job planning to enable psychiatrists to fulfil their CPD requirements in the face of competing demands on their clinical time and reducing resource.
Service line management and medical education – uncomfortable bed fellows?
Authors: Bailey Alex , Warner James P.
Published: March 2011

The current method of delivery of psychiatric training and education in the UK is still almost solely based on the ‘firm’ or consultant-led system. Traditionally, these units have had fairly wide-ranging loci of clinical responsibility, ensuring a broad exposure to mental health conditions for both undergraduate students and psychiatric trainees. However, changes over the past decade, particularly in terms of functional splits within psychiatric services, have led to some limitation of this exposure. Various strategies have been employed by those responsible for educational provision within services, such as assigning trainees and students to in-patient and community ‘pairs' of teams. Although this has had some success, the introduction of more fundamental restructuring of mental health services and the advent of service lines will have even greater and more wide-ranging implications on education. This editorial examines some of these implications and looks at potential solutions to ensure that training is not forgotten in the wave of far-reaching and strategically driven reorganisations occurring within the National Health Service and more globally.
Risk-Adapted Management of Differentiated Thyroid Cancer Assessed by a Sensitive Measurement of Basal Serum Thyroglobulin
Authors: Malandrino Pasqualino , Latina Adele , Marescalco Salvatore , Spadaro Angela , Regalbuto Concetto , Fulco Rosa Anna , Scollo Claudia , Vigneri Riccardo , Pellegriti Gabriella
Published: March 2011

Context:

Treatment and follow-up of patients thyroidectomized for differentiated thyroid carcinoma (DTC) mainly depends on the identification of the patient's risk of recurrence. Thyroglobulin (Tg) is the most important marker of persistent/recurrent disease. The recent introduction of a new, more sensitive Tg measurement allows for the early detection of the disease by measuring the basal (under l-T4 therapy) serum Tg level without TSH stimulation.

Objective:

The goal of this study is to identify the basal serum Tg threshold value that indicates recurrent disease by using a second-generation Tg assay.

Design and Patients:

A continuous series of 425 DTC patients, all thyroidectomized and treated with 131I after surgery and having basal Tg of no more than 1.0 ng/ml, negative anti-Tg antibodies, and a recombinant human TSH-stimulated Tg measurement was retrospectively analyzed.

Setting:

The study took place at an academic hospital.

Results:

The most accurate basal Tg value for predicting the presence of recurrent/residual disease was more than 0.15 ng/ml (sensitivity 87%, specificity 91%, negative predictive value 98.6%, and positive predictive value 47.8%). When the basal Tg level was no more than 0.15 ng/ml, the risk of disease presence was very low, even in patients classified at an intermediate or high risk. In contrast, when the basal Tg level was more than 0.15 ng/ml, the percentage of recurrent disease was relatively high (12.5% or one in eight cases) in low-risk patients.

Conclusions:

Basal Tg, measured using a second-generation Tg assay allows for the identification of DTC patients who are likely to remain disease free with great accuracy. This simple measurement, therefore, may be sufficient to assess the risk-adapted management of DTC patients.
Study of Platinum Dissolution Mechanism Using a Highly Sensitive Electrochemical Quartz Crystal Microbalance
Authors: Sakurai Takara , Shibata Masayo , Horiuchi Reiko , Yagi Ichizo , Kondo Toshihiro
Published: March 2011

Platinum (Pt) dissolution during oxidation/reduction cycle in various potential cycle ranges and in various pHs of the oxygen-saturated and deaerated H2SO4 and HClO4 electrolyte solutions was monitored by the highly sensitive electrochemical quartz crystal microbalance (EQCM) system. It was found that the Pt mass reduction depended on the potential cycle range and pH of the electrolyte solution with dissolved oxygen. Based on these results, it can be suggested that the dissolution of Pt requires one proton per one Pt and that it also requires dissolved oxygen, and then we can conclude that the dissolution reaction of Pt is as followings; PtO + H+ + 1/2O2 + H2O → Pt(OH)3+ and/or PtOH + H+ + 3/4O2 + 1/2H2O → Pt(OH)3+.
Central washout sign in computer-aided evaluation of breast MRI: preliminary results
Authors: Ko Eun Sook , Choi Hye Young , Lee Byung Hee , Noh Woo-Chul , Kim Rock Bum
Published: March 2011

Background

Although computer-aided evaluation (CAE) programs were introduced to help differentiate benign tumors from malignant ones, the set of CAE-measured parameters that best predict malignancy have not yet been established.

Purpose

To assess the value of the central washout sign on CAE color overlay images of breast MRI.

Material and Methods

We evaluated the frequency of the central washout sign using CAE. The central washout sign was determined so that thin, rim-like, persistent kinetics were seen in the periphery of the tumor. Then, sequentially, plateau and washout kinetics appeared. Two additional CAE-delayed kinetic variables were compared with the central washout sign for assessment of diagnostic utility: the predominant enhancement type (washout, plateau, or persistent) and the most suspicious enhancement type (any washout > any plateau > any persistent kinetics).

Results

One hundred and forty-nine pathologically proven breast lesions (130 malignant, 19 benign) were evaluated. A central washout sign was associated with 87% of malignant lesions but only 11% of benign lesions. Significant differences were found when delayed-phase kinetics were categorized by the most suspicious enhancement type ( P < 0.001) and the presence of the central washout sign ( P < 0.001). Under the criteria of the most suspicious kinetics, 68% of benign lesions were assigned as plateau or washout pattern.

Conclusion

The central washout sign is a reliable indicator of malignancy on CAE color overlay images of breast MRI.
High-resolution TOF MR angiography at 4.7 Tesla for volumetric and morphologic evaluation of coiled aneurysm neck remnants in a rat model
Authors: Marjamaa Johan , Antell Henrik , Abo-Ramadan Usama , Hernesniemi Juha A , Niemelä Mika R , Kangasniemi Marko
Published: March 2011

Background

Detection of morphologic and volumetric changes in aneurysm necks is important when evaluating the effects of endovascular devices for aneurysm occlusion.

Purpose

To optimize high-resolution 3D-TOF MRA at 4.7 T in order to achieve the best aneurysm-to-background contrast in experimental rat aneurysms, and to quantify the volume of the aneurysm neck by imaging.

Material and Methods

Saccular aneurysms in the abdominal aorta of rats were coiled with platinum coils. Tissue relaxation times were measured, and used in a mathematical simulation. To optimize 3D-TOF angiography, imaging parameters were varied within the range obtained from the simulations. Tissue contrast and contrast-to-noise ratio were measured from MR images. TOF images were compared to conventional spin echo and gradient echo images and to endoscopic and histological analyses.

Results

Parameters yielding the best aneurysm-to-background contrast and contrast-to-noise ratio were determined. The agreement between the results from in vivo imaging and simulation was good. The optimized 3D-TOF MRA sequence (TR/TE/FA = 60 ms/6.6 ms/20°) had an isotropic voxel size of 117 µm, which enabled measurement of the aneurysm neck volume.

Conclusion

High-resolution 3D-TOF angiography enables non-invasive quantification of changes in neck remnants of endovascularly coiled experimental aneurysms. In this model innovations like bioactive coils can be accurately tested for their efficacy for aneurysm occlusion.
Contrast-enhanced ultrasonographic findings of different histopathologic types of breast cancer
Authors: Wang Xiaohong , Xu Ping , Wang Yi , Grant Edward G
Published: March 2011

Background

The new application of contrast-enhanced ultrasonography (CEUS) in the diagnosis of breast masses has evolved quickly only in recent years. Nevertheless, mixed results owing to the overlap in characteristics of benign and malignant lesions are simultaneously discovered by most studies, partially attributed to different histopathologic characteristics of breast cancer.

Purpose

To explore the characteristics of different histopathologic types of breast cancer at real-time gray-scale CEUS and evaluate its diagnostic value.

Material and Methods

One hundred and one histopathologically confirmed malignant lesions were included. We retrospectively reviewed the contrast-enhanced ultrasonographic findings including morphologic features, quantitative parameters, and correlated them with histopathology. True-positive rate was calculated to assess the diagnostic performance of CEUS.

Results

The 101 malignancies displayed irregular shape (72 [71%]), poorly-defined margin (73 [72%]), penetrating or tortuous surrounding vessels (79 [78%]), heterogeneous enhancement (84 [83%]), including focal perfusion defects (24 [24%]). For each histopathologic type, 87% (58/67) of invasive ductal carcinoma (IDC) showed heterogeneous enhancement. Of all the 24 perfusion defects, IDC account for 88% (21/24). Low average peak intensity (PI) of 4.9 was detected in this type. Ductal carcinoma in situ (DCIS) excellently showed the features of irregular shape (82% [14/17]), poorly-defined margin (82% [14/17]), heterogeneous enhancement (94% [16/17]). While 83% (5/6) of medullary carcinoma exhibited regular shape, well-defined margin, homogenous enhancement, and high average PI value of 9.6. Invasive lobular carcinoma showed similar enhancement pattern to that of IDC. Intraductal papillary carcinoma displayed high average PI value of 8.1. The overall true-positive rate for conventional US and CEUS was 88%, 86%, respectively. DCIS, medullary carcinoma, and intraductal papillary carcinoma achieved an improved true-positive rate (94%, 100% and 100%, respectively).

Conclusion

The imaging characteristics of CEUS are variable in different histopathologic types of breast cancer. CEUS does not appear to be superior to conventional ultrasound as a diagnostic tool overall, however, it is a useful adjunct to conventional ultrasound in diagnosing some special types of breast cancer.
Cortical restricted diffusion as the predominant MRI finding in sporadic Creutzfeldt-Jakob disease
Authors: Talbott Sabrina D , Plato Brian M , Sattenberg Ronald J , Parker John , Heidenreich Jens O
Published: March 2011

Creutzfeldt-Jakob disease is a rare and fatal neurodegenerative disorder with MR findings predominantly limited to the grey matter of the cortex and the basal ganglia. Sporadic Creutzfeldt-Jakob disease can produce a spectrum of MR imaging findings of the brain, most notably on DWI and FLAIR sequences. Involvement of the basal ganglia and neocortex is the most common finding, but isolated involvement of the cortex can also be seen. We describe the clinical history and MRI findings of three patients with sporadic Creutzfeldt-Jakob disease confirmed by brain biopsy or autopsy and review the literature of imaging manifestations of this disease.
Endovenous laser ablation and foam sclerotherapy for varicose veins: does the presence of perforating vein insufficiency affect the treatment outcome?
Authors: Köroğlu Mert , Eriş Hüseyin Naim , Aktaş Aykut Recep , Kayan Mustafa , Yeşildağ Ahmet , Çetin Meltem , Parlak Cem , Gürses Cemil , Akhan Okan
Published: March 2011

Background

Superficial venous insufficiency is a common problem associated with varicose veins. Endovenous laser ablation (EVLA) and concomitant ultrasound (US)-guided foam sclerotherapy are recent treatment methods alternative to surgery in the treatment of superficial venous insufficiency.

Purpose

To compare the effectiveness of EVLA and concomitant US-guided foam sclerotherapy prospectively in two different subgroups of the disease (isolated truncal vs. truncal with perforating vein insufficiency).

Material and Methods

The study was approved by the institutional review board. Fifty-five patients with symptomatic saphenous vein insufficiency and varicose veins were included in the study. Seventy-three EVLA and concomitant foam sclerotherapy were performed for 60 lower extremities. To determine the severity of the venous disease, Venous Clinical Severity Score (VCSS) and Visual Analogue Scale (VAS) were carried out before and 6 months after the treatment. Patients were followed up clinically and with Doppler ultrasonography for 6 months after the procedures.

Results

At the sixth month of the follow-up; the total occlusion rate for the saphenous veins was 98.64% (72/73), and re-canalization rate was 1.36% (1/73). The total occlusion rate for the perforating veins was 75% (18/24), re-canalization rate was 25% (6/24). There was no notable major complication. VCSS and VAS scores were decreased significantly following the treatment (p < 0.05). The patients who had isolated saphenous vein insufficiency (Group I: 36/60) and those who had saphenous and perforating vein reflux (Group II: 24/60) were compared. VAS scores were more prominently decreased after the treatment in the isolated saphenous vein insufficiency group (p < 0.05). VCSS were also decreased more prominently in Group I when compared to Group II.

Conclusion

EVLA and concomitant US-guided foam sclerotherapy are effective, safe, and minimally invasive treatment options, yielding good cosmetic and clinical results in both isolated truncal and truncal with perforating vein insufficiency groups. However, clinical results and satisfaction of the patients were remarkably superior in cases with isolated truncal vein insufficiency compared to truncal and perforating vein insufficiency.
Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging of bone marrow in healthy individuals
Authors: Hillengass Jens , Stieltjes Bram , Bäuerle Tobias , McClanahan Fabienne , Heiss Christiane , Hielscher Thomas , Wagner-Gund Barbara , Habetler Verena , Goldschmidt Hartmut , Schlemmer Heinz-Peter , Delorme Stefan , Zechmann Christian M
Published: March 2011

Background

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) displays microcirculation and permeability by application of contrast-media and diffusion-weighted imaging (DWI) is a tool for quantification of cellularity in the investigated area. Recently published examples cover breast cancer, CNS tumors, head and neck cancer, gastrointestinal cancer, prostate cancer as well as hematologic malignancies.

Purpose

To investigated the influence of age, sex, and localization of the investigated region on findings of DCE-MRI and DWI.

Material and Methods

DCE-MRI-parameters amplitude A and exchange rate constant kep as well as the DWI-parameter ADC of the bone marrow of the lumbar vertebral column of 30 healthy individuals covering the typical range of age of tumor patients were evaluated. ADC was calculated using b=0 and a maximal b value of either 400 or 750 s/mm2.

Results

Amplitude A of DCE-MRI decreased with age ( P = 0.01) and amplitude A, exchange rate constant kep as well as ADC based on b = 400 s/mm2and b = 750 s/mm2,respectively, decreased significantly from the first to the fifth lumbar vertebra with P = 0.02, P = 0.05, P = 0.003, and P = 0.002, respectively.

Conclusion

Quantitative parameters of functional imaging techniques in bone marrow are influenced by the age of the examined individual and the anatomical location of the investigated region.
Outcome and prognostic factors of spontaneous ruptured hepatocellular carcinoma treated with transarterial embolization
Authors: Shin Byung Seok , Park Mi-Hyun , Jeon Gyeong Sik
Published: March 2011

Background

Rupture of hepatocellular carcinoma (HCC) is a life-threatening condition accompanied by hemorrhage. Transarterial embolization/chemoembolization (TAE/TACE) can be used as the first-line treatment to achieve initial homeostasis.

Purpose

To investigate the outcome of TAE/TACE for spontaneous ruptured HCC and to determine the prognostic factors affecting survival.

Material and Methods

We retrospectively reviewed the clinicoradiologic data of 47 patients (8 women, 39 men; median age 64.4 years) with serum bilirubin levels <3.0 mg/dL that underwent TAE/TACE for ruptured HCC between January 2004 and June 2010. Survival rates were estimated using the Kaplan-Meier method and prognostic factors of poor survival were obtained by univariate and multivariate analyses.

Results

The clinical success rate of TAE/TACE was 94% (44/47). The median survival time was 179.6 days. The 1-month, 3-month, 6-month, and 12-month survival rates were 75%, 54%, 48%, and 43%, respectively. Old age, a previous history of TACE for HCC, low initial hemoglobin level, higher blood transfusion requirement, Child-Pugh class C, high serum bilirubin level, low serum albumin level, prolonged prothrombin time, high serum creatinine level on admission, presence of encephalopathy, severe ascites, lobar TAE/TACE, presence of portal vein thrombosis, and tumors involving both lobes were associated with poor survival. Multivariate analysis revealed that higher blood transfusion requirement, Child-Pugh class C, presence of portal vein thrombosis, and tumors involving both lobes were significant predictors of poor survival.

Conclusion

TAE/TACE is effective for achieving initial hemostasis, which is critical to survival. Regardless of successful TAE/TACE, the survival rate in patients with Child-Pugh class C remains poor. Portal vein thrombosis and tumor extent are significant image parameters for predicting survival after TAE/TACE for ruptured HCC.
MRI features of intraductal papilloma of the breast: sheep in wolf's clothing?
Authors: Kurz Kathinka D , Roy Sumit , Saleh Andreas , Diallo-Danebrock Raihana , Skaane Per
Published: March 2011

Background

Intraductal papillomas often present as small, smooth masses, dilated ducts or microcalcifications at mammography and as smooth, hypoechoic masses at sonography. At magnetic resonance imaging (MRI), intraductal papillomas often present as small smooth masses, however, often with strong enhancement with type 2 or 3 time intensity curves. The result of the MR analysis is therefore not infrequently inconclusive in order to characterize the mass as benign or malignant.

Purpose

To characterize the appearance of intraductal papillomas of the breast at MRI, and determine whether the application of diagnostic rules described in literature could contribute to correctly classifying the lesions as benign.

Material and Methods

Twenty patients with histologically proven intraductal papillomas were included. Two radiologists independently reviewed the MR images of the breast. The BI-RADS® nomenclature was used to describe morphology and contrast-enhancement kinetics. Interobserver agreement in the interpretation of the MR images by the two investigators was performed. Kappa coefficient was calculated as index for the level of agreement. Subsequently, three sets of diagnostic rules, including the Göttinger score described by Fischer and the interpretation flowcharts according to Kinkel and to Tozaki were applied to characterize whether a biopsy should be recommended or not.

Results

All papillomas presented as masses on dynamic contrast-enhanced MRI. Only five papillomas showed a round, oval, or lobulated shape combined with smooth margins and continuous rise of the time intensity curve. Using the Göttingen score, biopsy would be recommended in 16 patients. Based on the interpretation flowcharts of Kinkel and of Tozaki, an additional 13 and 10 papillomas, respectively, were correctly classified as benign. Dilated ducts were visible in 10 patients. The interobserver agreement was good or excellent for all included variables.

Conclusion

Including systematic analysis of breast MRI to the diagnostic protocol and interpreting the images according to predetermined diagnostic rules, most solitary intraductal papillomas of the breast may be correctly characterized as benign.
Using intervention mapping to develop a family-based childhood weight management programme
Authors: Pittson Helen , Wallace1 Louise
Published: April 2011

Objectives

To develop, implement and evaluate a family-based childhood weight management programme.

Methods

Programme development utilized Bartholomew's Intervention Mapping framework. This six step structured approach provides planners with a framework that links determinants of health behaviours with performance objectives and strategies to be incorporated into programme design. Using this process a needs analysis and literature review were undertaken, a steering group formed, six focus groups (with a total of n = 47 pupils) were completed and six interviews took place with parents. The determinants were combined with relevant theories to develop the programme. Y W8? is a 12 week course for families with children aged 8-13 years designed to assist with weight management. Participants’ height, weight and physical activity levels along with self-esteem scores for children are recorded pre- and post-intervention and at three, six and 12 month follow-up. This paper documents post-course results at 12 weeks.

Results

Preliminary results showed children (mean pre-BMI = 28.48 (+4.44), mean post-BMI = 27.48 (+4.45; P = <0.001) and parents (mean pre-BMI = 30.77 (+6.21), mean post-BMI = 30.41 (+6.17; P = 0.017) decreased their BMI over the 12 weeks. These results compare favourably with similar programmes in the UK.

Conclusions

Intervention mapping was a useful approach for developing a theory based intervention. Results suggest Y W8? improves the body mass index (BMI) of children and parents at 12 weeks. Further work, including a randomized controlled trial (RCT), will confirm this, investigate the longer-term effectiveness and determine how the effects are mediated by psychological processes.
The challenges of undertaking root cause analysis in health care: A qualitative study
Authors: Nicolini Davide , Waring1 Justin , Mengis2 Jeanne
Published: April 2011

Objectives

Root cause analysis (RCA) is a framework for structured investigations of safety incidents. Our aim was to identify the barriers to successful learning in health care and to make recommendations for service development.

Methods

A qualitative study that ‘tracked’ the investigation procedures and practices of ten patient safety incidents in two National Health Service (NHS) hospitals. Non-participant observations of the complete investigation process in various managerial and administrative settings, together with semi-structured qualitative interviews with those involved in the process, and following the completion of the final report.

Results

There are several challenges to undertaking root cause analysis in health care. These are associated with forming and leading the investigation team; gathering and analysing supporting evidence; and formulating and implementing service improvements. Undertaking root cause analysis remains a complex non-linear task which entails balancing a multiplicity of concerns and expectations. Supporting enhanced incident investigation requires keeping in focus the instrumental aim of triggering sustainable service improvement and not for the investigation to become an end in itself.

Conclusions

Health services leaders need to provide open endorsement of root cause analysis and of the staff carrying it out; enhance staff participation within learning activities and new analytic tools; and develop capabilities in change management.
Multiple mechanisms collaborate to repress nanos translation in the Drosophila ovary and embryo
Authors: Andrews Shane , Snowflack Danielle R. , Clark Ira E. , Gavis Elizabeth R.
Published: April 2011

Translational control of gene expression is essential for development in organisms that rely on maternal mRNAs. In Drosophila, translation of maternal nanos (nos) mRNA must be restricted to the posterior of the early embryo for proper patterning of the anterior-posterior axis. Spatial control of nos translation is coordinated through the localization of a small subset of nos mRNA to the posterior pole late in oogenesis, activation of this localized mRNA, and repression of the remaining unlocalized nos mRNA throughout the bulk cytoplasm. Translational repression is mediated by the interaction of a cis-acting element in the nos 3′ untranslated region with two proteins, Glorund (Glo) and Smaug (Smg), that function in the oocyte and embryo, respectively. The mechanism of Glo-dependent repression is unknown. Previous work suggests that Smg represses translation initiation but this model is not easily reconciled with evidence for polysome association of repressed nos mRNA. Using an in vitro translation system, we have decoupled translational repression of nos imposed during oogenesis from repression during embryogenesis. Our results suggest that both Glo and Smg regulate translation initiation, but by different mechanisms. Furthermore, we show that, during late oogenesis, nos translation is also repressed post-initiation and provide evidence that Glo mediates this event. This post-initiation block is maintained into embryogenesis during the transition to Smg-dependent regulation. We propose that the use of multiple modes of repression ensures inactivation of nos RNA that is translated at earlier stages of oogenesis and maintenance of this inactivate state throughout late oogenesis into embryogenesis.
On some classes of inverse problems for parabolic equations
Authors: Pyatkov Sergey Grigir'evich
Published: April 2011

We study solvability of inverse problems of finding the right-hand side together with a solution itself for vector-valued parabolic equations. The usual boundary conditions are supplemented with the overdetermination conditions which are the values of a solution on some system of surfaces.
Recombinant Mycobacterium smegmatis vaccine candidates
Authors: Faludi Ildikó , Szabó Ágnes , Burián Katalin , Endrész Valéria , Miczák A.
Published: March 2011

Mycobacterium smegmatisis a species of rapidly growing saprophytes with a number of properties that make it an effective vaccine vector. RecombinantM. smegmatisexpressing protective antigens of different pathogens and molecules modulating the immune responses offers some potential for reduction of the burden of tuberculosis, HIV and hepatitis B infections. This paper discusses the molecular methods used to generate recombinantM. smegmatisand the results obtained with some of these recombinants.
Phylogenetic analysis of a nosocomial transmission of hepatitis B virus at a paediatric haematology ward
Authors: Dencs Ágnes , Farkas Ágnes , Gyugos Mónika , Kurcz Andrea , Puskás Erzsébet , Tresó B. , Rusvai Erzsébet , Barcsay Erzsébet , Takács Mária
Published: March 2011

A nosocomial Hepatitis B virus (HBV) outbreak at a paediatric onco-haematology unit was investigated using molecular biological methods to determine the origin of the infections. The National Reference Laboratory of Hepatitis Viruses received seven HBsAg positive sera from patients and one from the brother of a patient. A fragment of the preS1/preS2/S genes from all samples was amplified, the PCR products were sequenced and a rooted phylogenetic tree was constructed. All nucleotide sequences from the different patients were very similar and 6 of the 8 sequences were identical, suggesting a common origin of the infections. These sequences were closely related to those amplified from a nosocomial HBV epidemic in another hospital in Hungary. The on-scene investigation revealed several malpractices. The two hospital departments had close connections and some of the patients were treated in both institutions. Present report underlines the importance of developing screening protocols for hepatitis viruses and that of the introduction of regular training programs for health care professionals in the field of hospital hygiene.
Molecular analysis and antimicrobial susceptibility of methicillin resistant Staphylococcus aureus in one of the hospitals of Tehran University of Medical Sciences: High prevalence of sequence type 239 (ST239) clone
Authors: Shahsavan Shadi , Jabalameli Leila , Maleknejad Parviz , Aligholi Marzieh , Imaneini Hossein , Jabalameli Fereshteh , Halimi Shahnaz , Taherikalani Morovat , Khoramian Babak , Eslampour Mohammad , Feizabadi Mohammad , Emaneini Mohammad
Published: March 2011

Methicillin-resistantStaphylococcus aureus(MRSA), particularly the multidrug-resistant clones, is an increasing worldwide problem. The average incidence rate of MRSA in Tehran was found to be over 40%. A total of 140 MRSA isolates obtained from patients attending a teaching hospital in Tehran, from May 2009 to December 2009, were included in this study. The antimicrobial susceptibility profile of MRSA isolates was determined by the agar disk diffusion method. Molecular analysis of MRSA strains was accomplished by Pulsed-Field Gel Electrophoresis (PFGE) and Multi-locus sequence typing (MLST). Detection ofmecAgene was used to confirm resistance to methicillin among the MRSA isolates. All the MRSA isolates were susceptible to chloramphenicol, teicoplanin, tigecycline and vancomycin. All MRSAisolates were resistant to oxacillin, whilst 139 strains showed resistance against ciprofloxacin, erythromycin, gentamicin, tetracycline and trimethoprim-sulfamethoxazole. PFGE analysis of all the 140 MRSA isolates produced five distinct pulsotypes designated as pulsotypes A-E. Most of the isolates (n=132) were clustered into pulsotype A. The most prevalent sequence type (ST) was ST 239 (pulsotype A) found in 82% (37/45) of the tested isolates. The second most prevalent type was ST 1238 (pulsotypes B, C and D) found in 15% (7/45) of the isolates. The remaining type, ST 8 (pulsotype E) was found in a single isolate. The results of this study indicated that the MRSA clone ST 239 was a major clone in the selected university hospital of Tehran and that it was widely spread among the different wards as well as all the age groups of patients.