Leadership and mentoring in medical physics: The experience of a medical physics international mentoring program

Mentoring aims to improve careers and create benefits for the participants' personal and professional lives. Mentoring can be an individual or a shared experience for a group, while the mentor's role remains the same in both models. Mentors should increase confidence, teach, inspire, and set examples, helping the mentees to mould their path, contributing to the pursuit of their personal and professional goals. This study aims to report on the experience of early-career medical physics professionals and postgraduate students participating in a global mentoring program and to assess the impact of this activity on their professional development. The objectives of this mentoring program are to develop leadership roles among young medical physicists and to provide guidance and support. An online questionnaire was administered to the mentee participants. The analysis of their responses is reported in this work and the current status of the programme was examined using a SWOT analysis. In general, the mentoring experience had a positive impact on the mentees. The mentors were found especially helpful in the decision-making situations and in other conflicts that may arise with career development. Additionally, the mentees felt that mentoring contributed to the development of leadership skills required for the job market and assist in personal development. This paper concludes that participation of young medical physicists in a mentoring group program is beneficial to their career and therefore should be encouraged.

CHARACTERISATION AND EVALUATION OF AL2O3:C-BASED OPTICALLY STIMULATED LUMINESCENT DOSEMETER SYSTEM FOR DIAGNOSTIC X-RAYS: PERSONAL AND IN VIVO DOSIMETRY

This study characterises and evaluates an Al2O3:C-based optically stimulated luminescent dosemeter (OSLD) system, commercially known as the nanoDot™ dosemeter and the InLight® microStar reader, for personal and in vivo dose measurements in diagnostic radiology. The system characteristics, such as dose linearity, reader accuracy, reproducibility, batch homogeneity, energy dependence and signal stability, were explored. The suitability of the nanoDot™ dosemeters was evaluated by measuring the depth dose curve, in vivo dose measurement and image perturbation. The nanoDot™ dosemeters were observed to produce a linear dose with ±2.8% coefficient variation. Significant batch inhomogeneity (8.3%) was observed. A slight energy dependence (±6.1%) was observed between 60 and 140 kVp. The InLight® microStar reader demonstrated good accuracy and a reproducibility of ±2%. The depth dose curve measured using nanoDot™ dosemeters showed slightly lower responses than Monte Carlo simulation results. The total uncertainty for a single dose measurement using this system was 11%, but it could be reduced to 9.2% when energy dependence correction was applied.

A comparative study of radiation doses between phantom and patients via CT angiography of the intra-/extra-cranial, pulmonary, and abdominal/pelvic arteries

This study aimed to evaluate effective dose and size-specific dose estimate (SSDE) of computed tomography angiography (CTA) examination using an anthropomorphic phantom. We included three CTA examination protocols to evaluate the intra- and extra-cranial arteries, pulmonary artery (CTPA), and abdominal vessels. Patient SSDEs were measured retrospectively to estimate patient dose, relative to the bodyweight of the patient and volume CT dose index (CTDI_vol). Our findings revealed that the highest dose was absorbed by the left lobe of the thyroid gland during intra-/extra-cranial CTA and CTPA, that is, 14.11 ± 0.24 mGy and 16.20 ± 3.95 mGy, respectively. However, the highest absorbed dose in abdominal/pelvic CTA was the gonads (8.98 ± 0.30 mGy), while other radiosensitive organs in intra- and extra-cranial CTA, CTPA, and abdominal/pelvic CTA did not demonstrate significant differences between organs/structures with p value 0.88, 0.11, and 0.54, respectively. The estimated effective dose in intra-/extra-cranial CTA was lower in patients (0.80 ± 0.60 mSv) than in the phantom (0.83 mSv), but it was the opposite for CTPA, with the effective dose being higher in patients (7.54 ± 3.09 mSv) than in the phantom (6.68 mSv). Similar to the effective dose, only CTPA SSDEs were significantly higher in men than in women (19.74 ± 4.79 mGy versus 7.9 mGy). Effective dose and SSDE are clinically relevant parameters that can help estimate a more accurate patient dose based on a patient's size.

Diagnostic Efficacy of Synthesized 2D Digital Breast Tomosynthesis in Multi-ethnic Malaysian Population

Synthesized 2D images can be reconstructed from tomosynthesis images in breast imaging. This study aims to investigate the diagnostic efficacy of synthesized 2D images (C-View) in comparison to full field digital mammography (FFDM) when used with digital breast tomosynthesis (DBT) in multi-ethnic Malaysian population. FFDM and C-View images (n = 380) were independently evaluated by three readers through Breast Imaging Reporting and Data System (BI-RADS) categorisation, breast density and lesion characterisation. Statistical analysis was done comparing sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of C-View + DBT with FFDM + DBT as standard of reference. Very good interreader agreement in BI-RADS category and density assessment between C-View + DBT and FFDM + DBT, with high sensitivity, specificity, PPV and NPV of C-View + DBT when compared with FFDM + DBT. There was comparable PPV between C-View + DBT and FFDM + DBT, with histopathology as gold standard. High level of interreader agreement in BI-RADS category and density assessment for FFDM + DBT and C-View + DBT. There was good agreement between FFDM + DBT and C-View + DBT in mass characterization, and almost perfect agreement in calcification and asymmetric density. 52.2% lower radiation dose incurred when using C-View + DBT. Hence, synthesized 2D images are comparable to FFDM with reduction in radiation dose within the limits of Malaysian multi-ethnic population.

Photocatalytic regeneration of brominating agent in the visible light-mediated synthesis of imidazo[1,2-a]pyridines

Regenerating the brominating agent by erythrosine B closes a catalytic cycle for the construction of the imidazo[1,2-a]pyridine framework.

AFOMP policy number 6: code of ethics for medical physicists in AFOMP Countries

This policy statement, which is the sixth of a series of documents prepared by the Asia-Oceania Federation of Organizations for Medical Physics (AFOMP) Professional Development Committee, gives guidance on how medical physicists in AFOMP countries should conduct themselves in an ethical manner in their professional practice (Ng et al. in Australas Phys Eng Sci Med 32:175-179, 2009; Round et al. in Australas Phys Eng Sci Med 33:7-10, 2010; Round et al. in Australas Phys Eng Sci Med 34:303-307, 2011; Round et al. in Australas Phys Eng Sci Med 35:393-398, 2012; Round et al. in Australas Phys Eng Sci Med 38:217-221, 2015). It was developed after the ethics policies and codes of conducts of several medical physics societies and other professional organisations were studied. The policy was adopted at the Annual General Meeting of AFOMP held in Jaipur, India, in November 2017.

Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides

Two regiodivergent approaches to intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and amides have been developed, controlled by the reagents employed. With the Brønsted base KOt-Bu and CBrCl3 as radical initiator, benzo[d]imidazo[2,1-b]thiazoles are synthesized via attack at the α-carbon and keto carbon of the β-ketoester moiety. In contrast, switching to the Lewis acid catalyst, In(OTf)3, results in the regioselective nucleophilic attack at both carbonyl groups forming benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones instead.

Unintended and accidental medical radiation exposures in radiology: guidelines on investigation and prevention

This paper sets out guidelines for managing radiation exposure incidents involving patients in diagnostic and interventional radiology. The work is based on collation of experiences from representatives of international and national organizations for radiologists, medical physicists, radiographers, regulators, and equipment manufacturers, derived from an International Atomic Energy Agency Technical Meeting. More serious overexposures can result in skin doses high enough to produce tissue reactions, in interventional procedures and computed tomography, most notably from perfusion studies. A major factor involved has been deficiencies in training of staff in operation of equipment and optimization techniques. The use of checklists and time outs before procedures commence, and dose alerts when critical levels are reached during procedures, can provide safeguards to reduce the risks of these effects occurring. However, unintended and accidental overexposures resulting in relatively small additional doses can take place in any diagnostic or interventional x-ray procedure and it is important to learn from errors that occur, as these may lead to increased risks of stochastic effects. Such events may involve the wrong examinations, procedural errors, or equipment faults. Guidance is given on prevention, investigation, and dose calculation for radiology exposure incidents within healthcare facilities. Responsibilities should be clearly set out in formal policies, and procedures should be in place to ensure that root causes are identified and deficiencies addressed. When an overexposure of a patient or an unintended exposure of a foetus occurs, the foetal, organ, skin, and/or effective dose may be estimated from exposure data. When doses are very low, generic values for the examination may be sufficient, but a full assessment of doses to all exposed organs and tissues may sometimes be required. The use of general terminology to describe risks from stochastic effects is recommended rather than the calculation of numerical values, as these are misleading when applied to individuals.

Synthesis of Disubstituted 3-Phenylimidazo[1,2-a]pyridines via a 2-Aminopyridine/CBrCl3 α-Bromination Shuttle

A versatile protocol for the synthesis of disubstituted 3-phenylimidazo[1,2-a]pyridines by coupling 2-aminopyridine with phenylacetophenones, phenylacetones, or β-tetralone has been developed. Isolated yields of up to 97% were obtained at 80 °C within 5 h. The 2-aminopyridine/CBrCl₃ system acts as an α-bromination shuttle by transferring Br from CBrCl₃ to the α-carbon of the carbonyl moiety. This triggers a series of steps with double C-N/C-N bond formation to the final product. The distinct advantages of this protocol include the use of commercially available inexpensive substrates, simplicity of a metal-free one-pot synthesis, and ease of scale-up to multigram quantities.

Characterization of a MOSkin detector for in vivo skin dose measurements during interventional radiology procedures

PURPOSE

The MOSkin is a MOSFET detector designed especially for skin dose measurements. This detector has been characterized for various factors affecting its response for megavoltage photon beams and has been used for patient dose measurements during radiotherapy procedures. However, the characteristics of this detector in kilovoltage photon beams and low dose ranges have not been studied. The purpose of this study was to characterize the MOSkin detector to determine its suitability for in vivo entrance skin dose measurements during interventional radiology procedures.

METHODS

The calibration and reproducibility of the MOSkin detector and its dependency on different radiation beam qualities were carried out using RQR standard radiation qualities in free-in-air geometry. Studies of the other characterization parameters, such as the dose linearity and dependency on exposure angle, field size, frame rate, depth-dose, and source-to-surface distance (SSD), were carried out using a solid water phantom under a clinical x-ray unit.

RESULTS

The MOSkin detector showed good reproducibility (94%) and dose linearity (99%) for the dose range of 2 to 213 cGy. The sensitivity did not significantly change with the variation of SSD (± 1%), field size (± 1%), frame rate (± 3%), or beam energy (± 5%). The detector angular dependence was within ± 5% over 360° and the dose recorded by the MOSkin detector in different depths of a solid water phantom was in good agreement with the Markus parallel plate ionization chamber to within ± 3%.

CONCLUSIONS

The MOSkin detector proved to be reliable when exposed to different field sizes, SSDs, depths in solid water, dose rates, frame rates, and radiation incident angles within a clinical x-ray beam. The MOSkin detector with water equivalent depth equal to 0.07 mm is a suitable detector for in vivo skin dosimetry during interventional radiology procedures.

Genetic Interactions Between TRPC6 and NPHS1 Variants Affect Posttransplant Risk of Recurrent Focal Segmental Glomerulosclerosis

Individuals with TRPC6 mutations have variable phenotypes, ranging from healthy carrier to focal segmental glomerulosclerosis (FSGS) leading to renal failure. Here, we describe a family where six members had a novel TRPC6 p.R68W (c.202C>T) mutation, two of whom had renal failure from FSGS, and one had proteinuria. One healthy carrier donated a kidney to her sister. Both donor and recipient had no proteinuria at 20 years posttransplant. Two synonymous NPHS1 polymorphisms, rs2285450 (c.294C>T) and rs437168 (c.2289C>T) segregated with renal failure in this family. These variants had higher allele frequencies in 97 unrelated patients with nephrotic syndrome or FSGS compared to 224 controls. Using patch-clamp experiments in HEK293 and podocytes, we showed that the p.R68W mutation increased TRPC6 current amplitudes, which may be explained by enhanced TRPC6 surface expression. Additionally, while wild-type nephrin suppressed TRPC6 currents, this ability was lost in the presence of NPHS1 c.294C>T polymorphism. When cells were transfected according to combined TRPC6 and NPHS1 genotypes in the family, those representing the donor had lower TRPC6 currents than cells representing the recipient, suggesting that interactions between TRPC6 and NPHS1 variants could possibly account for the variable penetrance of TRPC6 mutations and the absence of recurrence in the graft.

The role of miR156/SPLs modules in Arabidopsis lateral root development

miR156 is an evolutionarily highly conserved miRNA in plants that defines an age-dependent flowering pathway. The investigations thus far have largely, if not exclusively, confined to plant aerial organs. Root branching architecture is a major determinant of water and nutrients uptake for plants. We show here that MIR156 genes are differentially expressed in specific cells/tissues of lateral roots. Plants overexpressing miR156 produce more lateral roots whereas reducing miR156 levels leads to fewer lateral roots. We demonstrate that at least one representative from the three groups of miR156 targets SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes: SPL3, SPL9 and SPL10 are involved in the repression of lateral root growth, with SPL10 playing a dominant role. In addition, both MIR156 and SPLs are responsive to auxin signaling suggesting that miR156/SPL modules might be involved in the proper timing of the lateral root developmental progression. Collectively, these results unravel a role for miR156/SPLs modules in lateral root development in Arabidopsis.

Annual review of children with tuberous sclerosis

Tuberous sclerosis complex is a complex childhood disorder characterised by the formation of hamartomas in multiple organs. Annual review of this disease is recommended to monitor the development of complications. We aim to provide a concise, evidence-based framework to assist clinicians during this annual review. We focus on the following areas: (A) what questions need to be asked during annual review, (B) which areas need emphasis on examination, (C) when is an investigation required and (D) referral to tertiary specialists and other members of the multidisciplinary team. It should also be noted that there are ongoing debates regarding screening intervals in certain areas. These include the frequency, modality of screening and degree of intervention for astrocytomas and renal angiomyolipomas. This review seeks to summarise the product of the ongoing debates, and provide evidence-based suggestions in light of the uncertainty.

The use of radiochromic EBT2 film for the quality assurance and dosimetric verification of 3D conformal radiotherapy using Microtek ScanMaker 9800XL flatbed scanner

Radiochromic and radiographic films are widely used for radiation dosimetry due to the advantage of high spatial resolution and two‐dimensional dose measurement. Different types of scanners, including various models of flatbed scanners, have been used as part of the dosimetry readout procedure. This paper focuses on the characterization of the EBT2 film response in combination with a Microtek ScanMaker 9800XL scanner and the subsequent use in the dosimetric verification of a 3D conformal radiotherapy treatment. The film reproducibility and scanner uniformity of the Microtek ScanMaker 9800XL was studied. A three‐field 3D conformal radiotherapy treatment was planned on an anthropomorphic phantom and EBT2 film measurements were carried out to verify the treatment. The interfilm reproducibility was found to be 0.25%. Over a period of three months, the films darkened by 1%. The scanner reproducibility was ± 2% and a nonuniformity was ±1.9% along the direction perpendicular to the scan direction. EBT2 measurements showed an underdose of 6.2% at high‐dose region compared to TPS predicted dose. This may be due to the inability of the treatment planning system to predict the correct dose distribution in the presence of tissue inhomogeneities and the uncertainty of the scanner reproducibility and uniformity. The use of EBT2 film in conjunction with the axial CT image of the anthropomorphic phantom allows the evaluation of the anatomical location of dose discrepancies between the EBT2 measured dose distribution and TPS predicted dose distribution.

PACS number: 87.55.Qr

Use of methylphenidate for the management of fatigue in Chinese patients with cancer

REASON FOR THE STUDY: Studies on methylphenidate for cancer-related fatigue showed conflicting results. This prospective study aims to determine whether methylphenidate is useful for relieving fatigue in Chinese patients with cancer. Chinese Version of Brief Fatigue Inventory (BFI-C) was administered on days 1, 8, and 29. Methylphenidate dose on day 1 was 5 mg daily then adjusted after day 8 according to response and side effects tolerance.

MAIN FINDINGS

Only 48% of the 25 recruited patients were on methylphenidate by day 29. Overall, no significant improvement in fatigue level was observed after methylphenidate, though benefits were shown in subgroups with age ≤ 65 and higher baseline BFI-C values.

PRINCIPAL CONCLUSIONS

Methylphenidate may be useful for management of cancer-related fatigue in selected Chinese patients.

Comparing contractile apparatus-driven cytokinesis mechanisms across kingdoms

Cytokinesis is the final stage of the cell cycle during which a cell physically divides into two daughters through the assembly of new membranes (and cell wall in some cases) between the forming daughters. New membrane assembly can either proceed centripetally behind a contractile apparatus, as in the case of prokaryotes, archaea, fungi, and animals or expand centrifugally, as in the case of higher plants. In this article, we compare the mechanisms of cytokinesis in diverse organisms dividing through the use of a contractile apparatus. While an actomyosin ring participates in cytokinesis in almost all centripetally dividing eukaryotes, the majority of bacteria and archaea (except Crenarchaea) divide using a ring composed of the tubulin-related protein FtsZ. Curiously, despite molecular conservation of the division machinery components, division site placement and its cell cycle regulation occur by a variety of unrelated mechanisms even among organisms from the same kingdom. While molecular motors and cytoskeletal polymer dynamics contribute to force generation during eukaryotic cytokinesis, cytoskeletal polymer dynamics alone appears to be sufficient for force generation during prokaryotic cytokinesis. Intriguingly, there are life forms on this planet that appear to lack molecules currently known to participate in cytokinesis and how these cells perform cytokinesis remains a mystery waiting to be unravelled.

Coronary CT angiography: current status and continuing challenges

Coronary CT angiography has been increasingly used in the diagnosis of coronary artery disease owing to rapid technological developments, which are reflected in the improved spatial and temporal resolution of the images. High diagnostic accuracy has been achieved with multislice CT scanners (64 slice and higher), and in selected patients coronary CT angiography is regarded as a reliable alternative to invasive coronary angiography. With high-quality coronary CT imaging increasingly being performed, patients can benefit from an imaging modality that provides a rapid and accurate diagnosis while avoiding an invasive procedure. Despite the tremendous contributions of coronary CT angiography to cardiac imaging, study results reported in the literature should be interpreted with caution as there are some limitations existing within the study design or related to patient risk factors. In addition, some attention must be given to the potential health risks associated with the ionising radiation received during cardiac CT examinations. Radiation dose associated with coronary CT angiography has raised serious concerns in the literature, as the risk of developing malignancy is not negligible. Various dose-saving strategies have been implemented, with some of the strategies resulting in significant dose reduction. The aim of this review is to present an overview of the role of coronary CT angiography on cardiac imaging, with focus on coronary artery disease in terms of the diagnostic and prognostic value of coronary CT angiography. Various approaches for dose reduction commonly recommended in the literature are discussed. Limitations of coronary CT angiography are identified. Finally, future directions and challenges with the use of coronary CT angiography are highlighted.

High-frequency hearing loss among mobile phone users

The objective of this study is to assess high frequency hearing (above 8 kHz) loss among prolonged mobile phone users is a tertiary Referral Center. Prospective single blinded study. This is the first study that used high-frequency audiometry. The wide usage of mobile phone is so profound that we were unable to find enough non-users as a control group. Therefore we compared the non-dominant ear to the dominant ear using audiometric measurements. The study was a blinded study wherein the audiologist did not know which was the dominant ear. A total of 100 subjects were studied. Of the subjects studied 53% were males and 47% females. Mean age was 27. The left ear was dominant in 63%, 22% were dominant in the right ear and 15% did not have a preference. This study showed that there is significant loss in the dominant ear compared to the non-dominant ear (P < 0.05). Chronic usage mobile phone revealed high frequency hearing loss in the dominant ear (mobile phone used) compared to the non dominant ear.

Strawberry gingivitis as the first presenting sign of Wegener's granulomatosis: report of a case

Wegener's granulomatosis is a rare multi-system disease characterized by the classic triad of necrotizing granulomas affecting the upper and lower respiratory tracts, disseminated vasculitis and glomerulonephritis. Oral lesions as a presenting feature are only encountered in 2% of these cases. Hyperplastic gingival lesions or strawberry gingivitis, is a characteristic sign of Wegener's granulomatosis. The latter consists of reddish-purple exophytic gingival swellings with petechial haemorrhages thus resembling strawberries. Recognition of this feature is of utmost importance for timely diagnosis and definitive management of this potentially fatal disease. A case of strawberry gingivitis as the first presenting sign of Wegener's granulomatosis affecting a 50-year-old Malay male is reported here. The differential diagnosis of red lesions that may present in the gingiva is discussed.

AFOMP Policy Statement No. 3: recommendations for the education and training of medical physicists in AFOMP countries

AFOMP recognizes that clinical medical physicists should demonstrate that they are competent to practice their profession by obtaining appropriate education, training and supervised experience in the specialties of medical physics in which they practice, as well as having a basic knowledge of other specialties. To help its member countries to achieve this, AFOMP has developed this policy to provide guidance when developing medical physicist education and training programs. The policy is compatible with the standards being promoted by the International Organization for Medical Physics and the International Medical Physics Certification Board.

Cardiac geometry in children receiving chronic peritoneal dialysis: findings from the International Pediatric Peritoneal Dialysis Network (IPPN) registry

BACKGROUND AND OBJECTIVES

Left ventricular hypertrophy (LVH) is an independent risk factor and an intermediate end point of dialysis-associated cardiovascular comorbidity. We utilized a global pediatric registry to assess the prevalence, incidence, and predictors of LVH as well as its evolution in the longitudinal follow-up in dialyzed children.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Cross-sectional echocardiographic, clinical, and biochemical data were evaluated in 507 children on peritoneal dialysis (PD), and longitudinal data were evaluated in 128 patients. The 95(th) percentile of LV mass index relative to height age was used to define LVH.

RESULTS

The overall LVH prevalence was 48.1%. In the prospective analysis, the incidence of LVH developing de novo in patients with normal baseline LV mass was 29%, and the incidence of regression from LVH to normal LV mass 40% per year on PD. Transformation to and regression from concentric LV geometry occurred in 36% and 28% of the patients, respectively. Hypertension, high body mass index, use of continuous ambulatory peritoneal dialysis, renal disease other than hypo/dysplasia, and hyperparathyroidism were identified as independent predictors of LVH. The use of renin-angiotensin system (RAS) antagonists and high total fluid output (sum of urine and ultrafiltration) were protective from concentric geometry. The risk of LVH at 1 year was increased by higher systolic BP standard deviation score and reduced in children with renal hypo/dysplasia.

CONCLUSIONS

Using height-adjusted left ventricular mass index reference data, LVH is highly prevalent but less common than previously diagnosed in children on PD. Renal hypo/dysplasia is protective from LVH, likely because of lower BP and polyuria. Hypertension, fluid overload, and hyperparathyroidism are modifiable determinants of LVH.

Laparoscopic sphincter-preserving total mesorectal excision: 10-year report

AIM

Total mesorectal excision (TME) is currently the gold standard for resection of mid or low rectal cancer and is associated with a low local recurrence rate. However, few studies have reported the long-term oncological outcome following use of a laparoscopic approach. The aim of this study was to evaluate the long-term oncological outcome after laparoscopic sphincter-preserving TME with a median follow up of about 4 years.

METHOD

Patients with mid or low rectal cancer who underwent laparoscopic sphincter-preserving TME with curative intent between March 1999 and March 2009 were prospectively recruited for analysis.

RESULTS

During the 10-year study period, 177 patients underwent laparoscopic sphincter-preserving TME with curative intent for rectal cancer. Conversion was required in two (1%) patients. There was no operative mortality. At a median follow-up period of 49 months, local recurrence had occurred in nine (5.1%) patients. The overall metastatic recurrence rate after curative resection was 22%. The overall 5-year survival and 5-year disease-free survival in the present study were 74% and 71%, respectively.

CONCLUSION

The results of this study show that laparoscopic sphincter-preserving TME is safe with long-term oncological outcomes comparable to those of open surgery.

Immunolocalization of notch signaling protein molecules in a maxillary chondrosarcoma and its recurrent tumor

Background

Notch receptors are critical determinants of cell fate in a variety of organisms. Notch signaling is involved in the chondrogenic specification of neural crest cells. Aberrant Notch activity has been implicated in numerous human diseases including cancers; however its role in chondrogenic tumors has not been clarified.

Method

Tissue samples from a case of primary chondrosarcoma of the maxilla and its recurrent tumor were examined immunohistochemically for Notch1-4 and their ligands (Jagged1, Jagged2 and Delta1) expression.

Results

Both primary and recurrent tumors were histopathologically diagnosed as conventional hyaline chondrosarcoma (WHO Grade I). Hypercellular tumor areas strongly expressed Notch3 and Jagged1 in spindle and pleomorphic cells suggesting up-regulation of these protein molecules at sites of tumor proliferation. Expression patterns were distinct with some overlap. Differentiated malignant and atypical chondrocytes demonstrated variable expression levels of Jagged1, and weak to absent staining for Notch1, 4 and Delta1. Protein immunolocalization was largely membranous and cytoplasmic, sometimes outlining the lacunae of malignant chondrocytes. Hyaline cartilage demonstrated a diffuse or granular precipitation of Jagged1 suggesting presence of soluble Jagged1 activity at sites of abnormal chondrogenesis. No immunoreactivity for the other Notch members was observed. Calcified cartilage was consistently Notch-negative indicating down-regulation of Notch with cartilage maturation. Stromal components namely endothelial cells and fibroblasts variably expressed Notch1, 3 and Jagged1 but were mildly or non-reactive for the other members.

Conclusions

Results indicate that Notch signaling pathway may participate in cellular differentiation and proliferation in chondrosarcoma. Findings implicate Notch3 and Jagged1 as key molecules that influence the differentiation and maturation of cells of chondrogenic lineage.

Publication ethics and scientific misconduct

To maintain the readers' trust and to uphold the journal's reputation, it is paramount for the entire research, peer reviewer and publication process to follow ethical principles and decisions. Studies involving humans, animals, medical records and human tissues/organs need to be conducted ethically, and the appropriate approvals obtained. The privacy and confidentiality of patients, authors and reviewers should be respected. When required, rights and permissions should be sought. Common forms of scientific misconduct include misappropriation of ideas, violation of generally accepted research practices, failure to comply with legislative and regulatory requirements, falsification of data, and inappropriate behaviour in relation to misconduct. Authors can expect editorial action to be taken, should duplicate publication, plagiarism and other forms of scientific misconduct be attempted or detected.

Good outcomes with mycophenolate-cyclosporine-based induction protocol in children with severe proliferative lupus nephritis

The outcomes of children with severe proliferative lupus nephritis (LN) were examined using a new mycophenolate and cyclosporine-based (MMF-CSA) induction protocol. Sixteen children with LN (WHO class III and IV), 31.3% of whom required dialysis at induction, were retrospectively studied. Median MMF dose was 942 mg/m( 2)/day. Thirteen patients (81%) with persistent proteinuria received CSA. Clinical and laboratory parameters were compared at pre-induction, 6 and 12 months. Treatment outcome was defined by Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), renal function, haematuria, proteinuria and serological markers (complements C3, C4 and anti-dsDNA). Comparing these parameters at induction, 6 months and 12 months, respectively, SLEDAI (25.4 +/- 8.7 versus 3.2 +/- 2.9 versus 2.9 +/- 2.8), serum C3 (47 +/- 21 versus 107 +/- 27 versus 111 +/- 38 mg/dl), C4 (12 +/- 14 versus 23 +/- 14 versus 22 +/- 11 mg/dl) and urine protein (6.97 +/- 7.09 versus 0.98 +/- 1.56 versus 0.21 +/- 0.13 g/ day/1. 73 m(2)) improved significantly (p < 0.05). Anti-dsDNA titres decreased in 73% by 6 and 12 months (p < 0.05). Complete renal remission was achieved in 7/16 (43.8%) at 6 months and 12/16 (75%) at 12 months, the rest achieving partial remission with no treatment failures. In conclusion, a combination MMF-CSA protocol is an effective therapeutic alternative for induction of children with severe proliferative LN, resulting in significant clinical and serological improvement with minimal adverse effects.

Conflict-of-interest, copyright and other declarations

Declarations of exclusive publication, author contribution, conflict-of-interest and copyright transfer are important formalities required by most biomedical journals. Conflict-of-interest may be personal, commercial, political, academic or financial. It is particularly important for authors to provide a full and complete disclosure of any financial relationship with a commercial organisation that may have an interest in the contents of the submitted manuscript. Editors, editorial board members and reviewers should also declare any possible conflicts-of-interest. The handling of conflict-of-interest during manuscript preparation, peer review and editorial decision making impacts the credibility of published articles and scientific research in general.

Getting to know journal bibliographic databases

A bibliographic database is an organised digital collection of references to published literature. A bibliographic database may be general in scope or may cover a specific academic discipline. There are many types of medical and general bibliographic databases. They cover biomedical and scientific literature, morbidity and mortality statistics, therapeutic regimens, medical records, images and reviews of evidence-based medicine. Getting to know these databases will help researchers and authors to enhance their writing and publishing endeavours.

Writing a book review

A book review is a form of academic writing that provides a succinct yet critical analysis evaluating the content, style, merit and significance of a book. The reader should gain insight into the strengths and weaknesses of the book, aided by input from the reviewer. The four stages of writing a book review are: introducing the book, outlining its contents, highlighting parts of the book by selecting particular chapters or themes, and giving a detailed evaluation.

Squamous odontogenic tumor of the mandible: a case report demonstrating immunoexpression of Notch1, 3, 4, Jagged1 and Delta1

Background

Squamous odontogenic tumor (SOT) is a rare benign odontogenic epithelial neoplasm. A slow-growing painless expansive swelling is the common presenting symptom. Histopathologically, SOT can be easily misdiagnosed as an acanthomatous ameloblastoma. Although Notch receptors and ligands have been shown to play a role in cell fate decisions in ameloblastomas, the role of these cell signaling molecules in SOT is unknown.

Case report

This paper describes a case of SOT affecting the anterior mandible of a 10-year-old Indian female. The patient was treated by local surgical excision and there has been no follow-up clinical record of recurrence 5 years after primary treatment. Histopathological examination revealed a solid, locally-infiltrative neoplasm composed of bland-looking squamatoid islands scattered in a mature fibrous connective tissue stroma and the diagnosis was SOT. Immunohistochemical evaluation showed positive reactivity of varying intensity in the neoplastic epithelial cells for Notch1, Notch3, Notch4, and their ligands Jagged1 and Delta1. Expression patterns showed considerable overlap. No immunoreactivity was detected for Notch2 and Jagged2.

Conclusions

Present findings suggest that Notch receptors and their ligands play differential roles in the cytodifferentiation of SOT.

Usefulness of plasma tissue inhibitors of metalloproteinases as markers of prognosis after acute myocardial infarction

Alterations in the balance of matrix metalloproteinase to tissue inhibitor of metalloproteinase (TIMP) are seen after acute myocardial infarction (AMI) and are associated with adverse left ventricular remodeling and prognosis in this setting. We aimed to investigate the association between TIMP levels and the occurrence of major adverse cardiac events (MACEs) after AMI. We measured plasma TIMP-1, -2, and -4 levels in 1,313 patients presenting with AMI. Subjects were followed over a median period of 520 days for the occurrence of MACEs. Clinical risk was assessed using the Global Registry of Acute Coronary Events (GRACE) score. All TIMP levels correlated with patient age and inversely with estimated glomerular filtration rate (all p values <0.001). Levels were higher in women versus men (p <0.001) and in subjects with a history of diabetes (TIMP-1, p <0.001; TIMP-2, p = 0.002; TIMP-4, p <0.001) or hypertension (TIMP-1, p = 0.031; TIMP-2, p <0.001; TIMP-4, p <0.001). TIMP-1 and TIMP-4 were higher in subjects with previous MI or angina (p <0.001). TIMP levels increased incrementally with quartiles of GRACE score (p <0.001). All TIMPs showed univariate association with the occurrence of MACEs (p <0.001). Areas under the receiver operator characteristic curve for prediction of MACE at 1 year were 0.61 for TIMP-1, 0.57 for TIMP-2, and 0.64 for TIMP-4. Combination of TIMPs with GRACE risk score revealed a greater area under the curve than GRACE score alone (0.72 vs 0.69, p = 0.0015). On multivariable Cox proportional hazards analysis, GRACE score (p <0.001) and plasma TIMPs (log TIMP-1, p = 0.017; log TIMP-2, p <0.001; log TIMP-4, p = 0.011) independently predicted MACEs. Using Kaplan-Meier analysis, the risk of MACEs increased incrementally with the number of TIMPs above their respective median (p <0.001 for all comparisons, log-rank test). In conclusion, higher plasma TIMP-1, -2, and -4 after AMI are associated with MACEs and provide additional prognostic information to that obtained from GRACE clinical risk scores alone.

Writing an editorial

An editorial may be written by the editor or someone invited by the editor. It serves many other purposes, including critiques of original articles published in the same issue of the journal, concise reviews of topics that do not warrant a full-length invited review, and other topics on very recent developments that are deemed by the editor to be important to readers of the journal and the community. As there is typically a limited space in which to deliver its contents, the message contained in the editorial needs to be well thought out and concisely delivered. It should contain the correct sequence of the elements of critical argument, ideally supported by evidence, and end with a clear conclusion.

418 cases of laparoscopic colorectal resections: a single-institution experience and literature review

INTRODUCTION

Evidence from randomised controlled trials has shown that laparoscopic colon and rectal cancer resection not only confers short-term benefits but also does not differ considerably in terms of its long-term oncological outcomes, as compared with open surgery.

METHODS

All laparoscopic colon and rectal resections performed between January 2005 and December 2007 were included. Patient records were reviewed from a prospective database and the relevant clinical data was obtained, with a subgroup analysis of cancer procedures performed.

RESULTS

418 patients (247 male), median age 63 years (range 24 to 88), underwent laparoscopic resection of the colon and rectum. The median Body Mass Index (BMI) was 22.5 (range 13.5 to 39.3). The majority of the procedures were performed for malignant disease (81.3 percent) and the most common procedure was anterior resection (79.4 percent). The median duration of surgery was 135 minutes (range 65 to 330), with conversions to open surgery in 44 patients (10.5 percent). Complications occurred in 78 patients (18.7 percent), including anastomotic leaks in five (1.20 percent). The median length of hospital stay was five days (range 3 to 90) and the median follow-up was 19 months (range 1 to 46). In the 340 patients with malignant disease, the median number of lymph nodes harvested was 13 (range 5 to 48), and at the latest review, 230 patients (67.6 percent) were disease-free, with locoregional recurrence in 2.9 percent and systemic recurrence in 10 percent.

CONCLUSION

To date, this is the largest series of laparoscopic colorectal resections reported locally, and our results show that it is safe, feasible and produces favourable results.

Writing a letter to the Editor

A letter to the Editor is a short communication. It can be written on any subject of interest to the journal reader, and is published at the Editor's discretion. Comments on previously published articles are probably the most common reason for writing a letter. A variety of other types of letters exist, depending on individual journal policy. Letters to the Editor should be objective, constructive and purposeful. They should provide new or useful information that merits publication, or additional or alternative viewpoint or experience to a previously published article. Letters should be short and concise, with clear and specific points.

Single-incision laparoscopic surgery for right hemicolectomy: our initial experience with 10 cases

BACKGROUND

Published data has confirmed the oncological safety and efficacy of laparoscopic colorectal surgery. Continued surgical innovation has seen the recent resurgence of single-port laparoscopic surgery. We present a series of 10 cases of single-incision laparoscopic surgery (SILS) for right hemicolectomy, with the aim of reaffirming the feasibility and favourable short-term results of this technique.

METHODS

Ten patients underwent SILS for right hemicolectomy using the SILS port, between June 2009 and August 2009. A longitudinal periumbilical incision was used as the access point for all cases. Data analysed included age, gender, American Society of Anaesthesiology score, body mass index (BMI), location of disease, duration of surgery, length of incision and duration of hospital stay. Inclusion criteria were no prior abdominal surgery, no intra-abdominal sepsis, no distant metastases and a BMI of <30.

RESULTS

All 10 cases of right hemicolectomy were successfully performed using the SILS port through a single periumbilical incision. The median age of patients was 64 years (range 48-83 years), with a median body mass index of 21.5 kg/m(2) (range 18.9-25.6 kg/m(2)). The median duration of surgery and hospital stay was 83 min (range 60-125 min) and 6 days (range 5-11 days), respectively. No morbidity or mortality was associated with this technique, and all patients recovered uneventfully.

CONCLUSION

This case series illustrates that SILS for right hemicolectomy is feasible and safe. However, the routine use of this innovative technique in malignant disease cannot be recommended without further large-scale prospective trials.

Writing an invited commentary

An invited commentary is a short article that describes an author's personal experience of a specific topic. Unlike a review article, the author gives his own opinions and perspectives. It typically addresses a current, hot and often controversial subject. It may take two formats, namely, provide an expert author's personal views of and insight into a current hot topic, or add balance to another paper being commented upon, with addition of the author's own perspective.

Is utilisation of computed tomography justified in clinical practice? Part IV: applications of paediatric computed tomography

Computed tomography (CT) has been recognised as the most widely used imaging technique in both adults and children, owing to technological developments, especially with the recent innovations in multislice CT. This has resulted in an increase in the use of CT examinations in children younger than 15 years of age in developed countries. The increasing use of paediatric CT in clinical practice has raised concerns regarding the potential risk of radiation-induced malignancy. This is because CT examinations deliver a much higher radiation dose than conventional radiographic techniques. Children are more sensitive to radiation exposure than adults and have a longer time ahead of them to manifest radiation-induced effects and injuries. Therefore, it is of paramount importance to reduce or minimise the radiation dose to children when choosing CT as the major imaging modality for diagnostic purposes. This article reviews the clinical applications of paediatric CT with regard to the adjustment of imaging protocols in routine clinical practice and in the emergency department, the justification of CT use in paediatric imaging, clinical awareness of CT-associated radiation risk and strategies to minimise radiation exposure to children.

Writing a systematic review

Evidence-based medicine (EBM) aims to combine the best available scientific evidence with clinical experience and individual judgment of patient needs. In the hierarchy of scientific evidence, systematic reviews (along with meta-analyses) occupy the highest levels in terms of the quality of evidence. A systematic review is the process of searching, selecting, appraising, synthesising and reporting clinical evidence on a particular question or topic. It is currently considered the best, least biased and most rational way to organise, gather, evaluate and integrate scientific evidence from the rapidly-changing medical and healthcare literature. Systematic reviews could be used to present current concepts or serve as review articles and replace the traditional expert opinion or narrative review. This article explains the structure and content of a systematic review.

Multislice CT angiography in cardiac imaging. Part III: radiation risk and dose reduction

With the introduction of 64- or more-slice computed tomography (CT) technology, multislice CT angiography has been increasingly used as a non-invasive modality for the diagnosis of coronary artery disease. Despite its potential advantages and promising clinical results, multislice CT angiography suffers from high radiation dose which contributes to radiation-induced malignancy in patients undergoing cardiac CT examinations. This has raised serious concerns in clinical practice. A number of strategies have been recommended and implemented to reduce the radiation dose associated with multislice CT angiography in cardiac imaging. The aim of this review is to present an overview of the various approaches used for radiation dose reduction. Future directions of multislice CT angiography with regard to the judicious use of this promising technique and increased awareness of the radiation risk are highlighted.

Multislice CT angiography in cardiac imaging. Part II: clinical applications in coronary artery disease

Multislice computed tomography (CT) angiography represents a technological evolution in cardiac imaging due to improved spatial and temporal resolution. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a viable and effective alternative to invasive coronary angiography in selected patients. Multislice CT angiography has demonstrated high sensitivity and specificity, and in particular, a very high negative predictive value, which makes it a valuable imaging modality for screening patients suspected of coronary artery disease. In addition, multislice CT angiography demonstrates accuracy in the detection and characterisation of coronary plaques, and it has been reported to play an important role in predicting disease progression and cardiac events. The aim of this review was to present an overview of the clinical applications of multislice CT angiography in coronary artery disease, with regard to its diagnostic accuracy and predictive value in coronary artery disease. Emerging areas of multislice CT, including dual-energy CT and CT myocardial perfusion, are also discussed. Limitations of multislice CT angiography and future directions of cardiac multislice CT are highlighted.

Writing an invited review

An invited review provides a detailed and comprehensive narrative analysis of recent developments in a specific topic, and highlights important points that have been previously published. It usually consists of a short unstructured abstract, introduction, subheadings to organise the topic, and a summary. The text is usually relatively long compared to other paper categories, typically up to 15 manuscript pages or 4,000 words. The reference list is expected to comprehensively cover all the major published work, with up to 50-75 references being typical. The ideal invited review should be topical, current, balanced, accurate, quotable and easily understood, with clear take-home messages.

An unsuspected ameloblastoma in the subpontic region of the mandible with consideration of pathogenesis from the radiographic course

The purpose of this report is to document a case of unsuspected ameloblastoma involving the right man dibular subpontic region in a 38-year-old Cambodian female patient. This lesion was purportedly preceded by multiple radiolucencies which were diagnosed as radi cular cysts and treated a few times in the past years by enucleation followed by endodontic therapy of the affected teeth. Bridgework restoration of the partially edentulous area was performed. This case report de monstrates radiographic changes that occurred in the periods before and after the diagnosis of amelo blas to ma. The case may represent an example of radicular cysts and ameloblastoma occurring as a collision phenomenon, or the ameloblastoma may have arisen as a result of neoplastic transformation of the lining epi thelium in an inflammatory odontogenic epithelial cyst.

Writing a pictorial essay

A pictorial essay is a type of educational article that aims to provide both textual and visual portrayals of a topical issue. It usually consists of a short unstructured abstract, brief introduction, subheadings to organise the material and a summary. The number of references is limited to a few key articles, typically, eight to 15, or fewer. The text is usually short, often approximately 1,000 to 2,000 words in length, with much of the message contained in the figure legends. This type of article allows for a large number of figures, typically up to 20 figures or 30 figure parts. The main criteria for publication are currency, educational value and high quality of illustrations.

Is utilisation of computed tomography justified in clinical practice? Part I: application in the emergency department

Computed tomography (CT) is currently a widely available imaging technique in clinical practice. Technical developments of CT imaging, especially the emergence of multislice CT, with increased scanning speed and volume as well as higher spatial and temporal resolution, have significantly enhanced the diagnostic value of CT in many clinical applications. CT has become an important diagnostic imaging modality in the emergency department, with high diagnostic accuracy and efficacy in both traumatic and non-traumatic conditions. There is, however, a growing concern about the risk of associated radiation exposure in the population exposed to CT examination. Justification of the application of CT is one of the main principles that physicians need to be aware of when choosing CT as the first-line technique for diagnosis. This article reviews the clinical applications of CT imaging in the emergency department, with a focus on patients presenting with headache, repeat and multiple CT imaging and whole body screening for trauma patients, and explores whether the applications are clinically justified.

Writing a technical note

A technical note is a short article giving a brief description of a specific development, technique or procedure, or it may describe a modification of an existing technique, procedure or device applicable to medicine. The technique, procedure or device described should have practical value and should contribute to clinical diagnosis or management. It could also present a software tool, or an experimental or computational method. Technical notes are variously referred to as technical innovations or technical developments. The main criteria for publication will be the novelty of concepts involved, the validity of the technique and its potential for clinical applications.