Evaluation of architectural distortion with contrast-enhanced mammography.

Architectural distortion (AD) is the third most common abnormality detected on mammograms. In the absence of an accurate non-invasive tool to evaluate ADs, clinical management often requires surgical excision for histological diagnosis. This problem is expected to worsen with the growing use of digital breast tomosynthesis (DBT) and the resultant increasing detection of ADs. There is therefore a great clinical need for a diagnostic imaging tool to complement non-enhanced mammography for the evaluation of AD. Contrast-enhanced mammography (CEM) is an emerging breast imaging method that uses contrast media and the principle of dual-energy subtraction to evaluate vascularity of suspicious breast lesions. CEM, a cost-effective alternative to breast magnetic resonance imaging (MRI), can be used to evaluate AD by juxtaposing CEM images with non-enhanced mammograms for comparison. In this review, the authors aim to provide readers with an overview of the interpretation of AD on CEM using imaging examples. Relevant imaging features of CEM and their respective significance will be matched with information from a literature review. Finally, the authors would like to highlight the added value of CEM in relevant clinical applications in the assessment of AD.

Solid state fermentation of mung beans by Bacillus subtilis subsp. natto on static, shaking flask and soft elastic tubular reactors.

Given that mung beans constitute a significant nutrient source in many cultures, it is worthwhile to investigate ways to improve their nutritional and functional properties. The effect of fermentation of mung beans by Bacillus subtilis subsp. natto was investigated in various reactor designs, including static, shaking flasks, and soft elastic tubular reactors (SETR). The results showed that all three processes might affect the substrate, resulting in changes in the protein and carbohydrate fractions. We noticed an increase in soluble protein and serine levels, which we attribute to the proteases produced during fermentation. Through XRD, FTIR, and DSC analyses, it was also discovered that whereas static and shaking flask fermentation might raise relative crystallinity and peak temperature, fermentation performed on the SETR decreased these values. It was also possible to notice that SETR might induce a change in the particle size distribution of the substrate through a complex impact of mechanical forces, mixing, and microbial activity, which could be helpful to some aspects of the process. To summarize, fermentation of mung beans by Bacillus. subtilis subsp. natto could be an attractive approach for producing a food ingredient with various functional and nutritional properties. Furthermore, the SETR has been shown to be a viable technique for dealing with high solid load substrates, whether as the reactor for the entire process or as a first stage/pre-treatment step, and its applicability in bioprocesses should be explored further.

The effect of parenting styles on enforcement of oral health behaviours in children.

PURPOSE: To examine the relationship between parenting styles and parental attitudes towards oral health practices in children. METHODS: Parents of children aged 4-6 years presenting to four public dental clinics completed the Parenting Styles Dimensions Questionnaire (PSDQ) and a questionnaire on parental attitudes, child diet and oral hygiene practices. Child oral health was evaluated using Plaque Index (PI) and dmft-Index. RESULTS: Three hundred and eighty-nine children (mean age: 62.3 ± 9.8 months) were recruited. The median dmft was 4 (IQR = 9) and median PI was 1.5 (IQR = 0.8). An authoritative parenting style was observed in 95.1% of parents. Authoritative parents were more likely to monitor sweets/snacks intake (P = 0.004) and less inclined to offer sweets/snacks in exchange for good behaviour (P = 0.04) than permissive parents. However, actual between-meal snacking frequency did not differ between styles (P = 0.43). Permissive parents were less likely to ensure bedtime toothbrushing (P = 0.001) or brush thoroughly when busy or tired (P = 0.03) compared to authoritative parents; these attitudes were associated with higher frequencies of actual omission of bedtime toothbrushing (P = 0.006) in their children. A higher frequency of omitting bedtime toothbrushing significantly predicted a permissive parenting style (OR = 12.1, P = 0.009). Parenting styles were not associated with dmft (P = 0.72) and/or PI (P = 0.34). CONCLUSIONS: Authoritative parenting was associated with positive attitudes regarding both preventive dietary and oral hygiene practices. Actual oral hygiene practices were more ideal in children with authoritative parents, but parenting styles had no impact on actual dietary habits.

Recovery of Lactobacillus casei strain Shirota (LcS) from faeces of healthy Singapore adults after intake of fermented milk.

To validate survival of Lactobacillus casei strain Shirota (LcS) during passage through the gastrointestinal tract of healthy Singaporean young adults, 21 participants (18-25 years old) were asked to consume a 100 ml of fermented milk drink containing 1.0×108 cfu/ml of LcS daily for 14 days, and to maintain their dietary habit and life style. During and at the end of the ingestion period, both culture method (identity confirmed by ELISA) and 16s rRNA sequencing results revealed that viable LcS (7.27 and 7.64 log10 cfu/g of faeces at the ingestion period Day 7 and Day 14, respectively) and Lactobacillus could be recovered from the faeces of all the subjects. The viable LcS count from male and female were comparable for each time point. Before consumption (baseline) and 14 days after cessation of consumption of the fermented milk, LcS was not detected in most of the subjects. In this study condition, the composition of the major gut microbiota (>0.1% in relative abundance of genus) and characteristics of defaecation such as stool consistency and frequency of defecation did not change throughout the study before and after ingestion of LcS. LcS was able to survive passage through the gastrointestinal tract of Singapore adults without sustainable colonisation, but the effect of LcS on microbiota modulation, stool consistency and frequency was not observed under this study condition.

Effect of staining beverages on color and translucency of CAD/CAM composites.

This study investigated the color (ΔE) and translucency changes (ΔTP) of CAD/CAM composites after exposure to staining solutions using both spectrophotometer and shade-matching device. Direct (Filtek Z350XT [ZT]), indirect (Shofu Ceramage [CE]) and CAD/CAM (Shofu HC Block [HC], Lava Ultimate [LU], Vita Enamic [EN]) composite specimens measuring 12 × 14 × 1.5 mm were fabricated, divided into five groups (n = 8), and immersed in cola, tea, coffee, red wine, distilled water (control) at 37°C for 7 days. Color parameters were determined with both spectrophotometer and shade-taking device at baseline and 1 week. Delta E (ΔE) with white and black backgrounds, and Delta TP (ΔTP) were computed. Statistical testing was performed with ANOVA and Tukey post hoc test (P < .05). Mean ΔE (white) values ranged from 0.20 ± 0.06 to 12.26 ± 1.95 while mean ΔE (black) varied from 0.22 ± 0.11 to 14.21 ± 2.37. Mean ΔTP values ranged from 0.13 ± 0.17 to -3.87 ± 2.16. CAD/CAM composites fared better in red wine than direct and indirect materials. Clinically perceptible color changes (ΔE > 3.3) were observed for almost all materials when exposed to wine, coffee and tea. Direct, indirect, and CAD/CAM composites are all susceptible to various degrees of discoloration and translucency changes after exposure to staining beverages. Red wine caused the most discoloration and translucency changes. Limitations of these materials must be considered when placing an aesthetic restoration. CLINICAL SIGNIFICANCE: Direct, indirect, and CAD/CAM composites are all susceptible to various degrees of discoloration and translucency changes after exposure to staining beverages. Red wine generally caused the most discoloration and translucency changes. Although CAD/CAM composites were more color stable than direct and indirect materials when exposed to red wine, color changes were still clinically perceptible.

Small particle size lipid emulsions, satiety and energy intake in lean men.

Lipid emulsions have been proposed to suppress hunger and food intake. Whilst there is no consensus on optimal structural properties or mechanism of action, small particle size (small-PS) stable emulsions may have greatest efficacy. Fabuless®, a commercial lipid emulsion reported in some studies to decrease energy intake (EI), is a small-PS, 'hard' fat emulsion comprising highly saturated palm oil base (PS, 82nm). To determine whether small-PS dairy lipid emulsions can enhance satiety, firstly, we investigated 2 'soft' fat dairy emulsions generated using dairy and soy emulsifying agents (PS, 114nm and 121nm) and a non-emulsified dairy control. Secondly, we investigated a small-PS palmolein based 'hard' fat emulsion (fractionated palm oil, PS, 104nm) and non-emulsified control. This was a 6 arm, randomized, cross-over study in 18 lean men, with test lipids delivered in a breakfast meal: (i) Fabuless® emulsion (FEM); (ii) dairy emulsion with dairy emulsifier (DEDE); (iii) dairy emulsion with soy lecithin emulsifier (DESE); (iv) dairy control (DCON); (v) palmolein emulsion with dairy emulsifier (PEDE); (vi) palmolein control (PCON). Participants rated postprandial appetite sensations using visual analogue scales (VAS), and ad libitum energy intake (EI) was measured at a lunch meal 3.5h later. Dairy lipid emulsions did not significantly alter satiety ratings or change EI relative to dairy control (DEDE, 4035kJ; DESE, 3904kJ; DCON, 3985kJ; P>0.05) nor did palm oil based emulsion relative to non-emulsified control (PEDE, 3902 kJ; PCON, 3973kJ; P>0.05). There was no evidence that small-PS dairy lipid emulsions or commercial Fabuless altered short-term appetite or food intake in lean adults.

Recurrent abdominal pain in children: a clinical approach.

The term 'recurrent abdominal pain', or RAP, refers mainly to the duration of painful period and frequency of pain. The commonly accepted duration is at least three months in the preceding period, and over this three-month period, there are at least three episodes of pain that are severe enough to affect the daily activities of the affected patients. Over the years, with advances in medical technology and better understanding of the pathophysiology of abdominal pain, more and more organic causes have been identified. However, the most common cause of RAP in children is still functional in origin.

Statistical atlas-based morphological variation analysis of the asian humerus: towards consistent allometric implant positioning.

PURPOSE: Positioning existing humeral implants into Asian patients poses significant challenges due to the inconsistent statistical shapes between Western population and Asian population. Current humeral orthopedic fixation devices and implants have a generic shape and are not designed for Asian patients who exhibit different sizes and shapes compared to their Western counterparts for which present day designs have been based on. To address this problem, it is necessary to develop Asian-specific implants that accommodate the morphology of Asian humeri. Existing morphological studies of humeri in Asian populations are rare and most previous analyses are either based on the manual measurement of dry bones or the use of dual energy X-ray absorptiometry scans. The purpose of this pilot morphological study is to explore the characteristics of Asian humeri using statistical atlas-based analysis. METHODS: Forty-four CT scans of normal upper limbs were obtained from the National University Hospital, Singapore and used to construct statistical humerus atlases. The atlases were subsequently used to study the morphology of the humeri in an Asian population. Humeral shapes of different patient clusters were analyzed based on statistical shape models. Comparison between different clusters was conducted with regard to centerline, length, width and surface curvature. RESULTS: The statistical humerus atlases reflected the mean shape and modes of variation of humeri in an Asian population. Analyses based on these atlases indicated that curvature and shape of the internal humeral canal were similar in males and females while humeral length and width were greater in males. Most importantly, surface curvatures were explicitly different between clusters. CONCLUSION: Morphologic analysis based on statistical atlases is novel and useful to characterize the Asian humerus. The humerus demonstrates gender-specific morphology. This unique approach provides information that is useful to the clinician and biomedical engineer, not only in the modification of current or design of future humeral implants, but also in the precise dynamic positioning of Asian-specific humeral implants to Asian patients. Our findings support the need for further development of humeral implants, curvilinear robotics, and the questioning of whether gender-specific devices are necessary.

On the failure load and mechanism of polycrystalline graphene by nanoindentation.

Nanoindentation has been recently used to measure the mechanical properties of polycrystalline graphene. However, the measured failure loads are found to be scattered widely and vary from lab to lab. We perform molecular dynamics simulations of nanoindentation on polycrystalline graphene at different sites including grain center, grain boundary (GB), GB triple junction, and holes. Depending on the relative position between the indenter tip and defects, significant scattering in failure load is observed. This scattering is found to arise from a combination of the non-uniform stress state, varied and weakened strengths of different defects, and the relative location between the indenter tip and the defects in polycrystalline graphene. Consequently, the failure behavior of polycrystalline graphene by nanoindentation is critically dependent on the indentation site, and is thus distinct from uniaxial tensile loading. Our work highlights the importance of the interaction between the indentation tip and defects, and the need to explicitly consider the defect characteristics at and near the indentation site in polycrystalline graphene during nanoindentation.

Inverse pseudo Hall-Petch relation in polycrystalline graphene.

Understanding the grain size-dependent failure behavior of polycrystalline graphene is important for its applications both structurally and functionally. Here we perform molecular dynamics simulations to study the failure behavior of polycrystalline graphene by varying both grain size and distribution. We show that polycrystalline graphene fails in a brittle mode and grain boundary junctions serve as the crack nucleation sites. We also show that its breaking strength and average grain size follow an inverse pseudo Hall-Petch relation, in agreement with experimental measurements. Further, we find that this inverse pseudo Hall-Petch relation can be naturally rationalized by the weakest-link model, which describes the failure behavior of brittle materials. Our present work reveals insights into controlling the mechanical properties of polycrystalline graphene and provides guidelines for the applications of polycrystalline graphene in flexible electronics and nano-electronic-mechanical devices.

Coarctation of the aorta: nonsurgical treatment using stent implantation.

INTRODUCTION: Coarctation of the aorta (CoA) accounts for 5%-8% of all congenital heart defects. If left untreated, most patients with significant CoA will have varying degrees of morbidity (e.g. hypertension, stroke, collateral formation and ventricular hypertrophy), possibly even mortality. Traditionally, treatment for this condition is surgical. Herein, we report stenting during catheterisation as an alternative nonsurgical treatment option for patients with CoA, and present the treatment outcomes of patients who underwent this treatment option. METHODS: We retrospectively reviewed four patients (2 men and 2 women; age range 20-41 years) who underwent CoA stenting under general anaesthesia for the treatment of native CoA or restenosis of CoA at our institution. Three patients had a 40-mm Palmaz stent inserted, while one had a 39-mm Cheatham-Platinum covered stent inserted. Angiography and measurement of pressure gradients were performed before and after stent implantation to ensure good treatment outcomes. RESULTS: The patients' treatment outcomes were good, with a significant reduction in pressure gradients across the narrowed segments. Angiography showed relief of CoA. The patients were followed up for 1-3 years, during which no complications were noted. CONCLUSION: This is the first reported series in Singapore on the nonsurgical treatment of CoAs in adult patients using stents during interventional cardiac catheterisation. This less invasive procedure may lead to a new paradigm shift with regard to the treatment of CoA.

Molecular imaging for depressive disorders.

Molecular imaging is the visualization, characterization, and measurement of biologic processes at the molecular and cellular levels in humans and other living systems. Molecular imaging techniques such as MR spectroscopy and PET have been used to explore the molecular pathophysiology of depression and assess treatment responses. MR spectroscopy is a noninvasive technique that assesses the levels of biochemical metabolites in the brain, while PET uses radioligands injected in the bloodstream that have high binding affinity for target molecules. MR spectroscopy findings suggest a role for glutamate/glutamine and gamma-aminobutyric acid in depression. PET has generally failed to find a correlation between radioligand binding potential and depression severity or treatment response, though it may offer promise in distinguishing responders and nonresponders to treatment. A major challenge for both modalities is that depression is a heterogeneous, multifactorial disorder, while MR spectroscopy and PET are limited to examining a few metabolites or a single radioligand at a time. This difference makes a comprehensive evaluation of neurochemical changes in the brain difficult.

Isolated cleft mitral valve with severe regurgitation resulting in a left inferior pulmonary vein varix diagnosed from cardiovascular magnetic resonance imaging.

Isolated cleft mitral valve (ICMV) is a rare entity not known to be related to pulmonary atresia with ventricular septal defect (PA-VSD). This report describes the use of cardiovascular magnetic resonance (CMR) imaging to diagnose ICMV in a patient with repaired PA-VSD who presented with incidental severe mitral regurgitation (MR) on follow-up echocardiography. An associated pulmonary varix secondary to the severe MR also was shown by CMR.

A power-law rheology-based finite element model for single cell deformation.

Physical forces can elicit complex time- and space-dependent deformations in living cells. These deformations at the subcellular level are difficult to measure but can be estimated using computational approaches such as finite element (FE) simulation. Existing FE models predominantly treat cells as spring-dashpot viscoelastic materials, while broad experimental data are now lending support to the power-law rheology (PLR) model. Here, we developed a large deformation FE model that incorporated PLR and experimentally verified this model by performing micropipette aspiration on fibroblasts under various mechanical loadings. With a single set of rheological properties, this model recapitulated the diverse micropipette aspiration data obtained using three protocols and with a range of micropipette sizes. More intriguingly, our analysis revealed that decreased pipette size leads to increased pressure gradient, potentially explaining our previous counterintuitive finding that decreased pipette size leads to increased incidence of cell blebbing and injury. Taken together, our work leads to more accurate rheological interpretation of micropipette aspiration experiments than previous models and suggests pressure gradient as a potential determinant of cell injury.

A re-look at an old disease: a multimodality review on gout.

Gout, the most common form of microcrystalline arthropathy has always interested radiologists. The diagnosis of gout is primarily based on clinical and laboratory findings; however, it has well known and characteristic radiographic manifestations. Radiographs remain the examination of choice in the diagnosis of joint involvement. Plain radiographs are less sensitive to early changes in gout than other imaging techniques. Recently, magnetic resonance imaging (MRI), ultrasound (US), and computed tomography (CT) have demonstrated an increasing role in early diagnosis of gouty arthritis, for assessing the extent of soft-tissue involvement and as problem-solving tools for diagnostically difficult cases. Cross-sectional imaging can also be used for guiding needle aspirations in patients with an acute attack of gout, which may simulate an infective process clinically. This pictorial review illustrates the main imaging features of gout on radiographs, MRI, CT, and ultrasound with the aim of helping the radiologist to make a confident diagnosis in radiographically typical cases and to serve as a problem-solving tool in cases that present a diagnostic dilemma.

Relating energy level alignment and amine-linked single molecule junction conductance.

Using photoemission spectroscopy, we determine the relationship between electronic energy level alignment at a metal-molecule interface and single-molecule junction transport data. We measure the position of the highest occupied molecular orbital (HOMO) relative to the Au metal Fermi level for three 1,4-benzenediamine derivatives on Au(111) and Au(110) with ultraviolet and resonant X-ray photoemission spectroscopy. We compare these results to scanning tunnelling microscope-based break-junction measurements of single molecule conductance and to first-principles calculations. We find that the energy difference between the HOMO and Fermi level for the three molecules adsorbed on Au(111) correlate well with changes in conductance and agree well with quasiparticle energies computed from first-principles calculations incorporating self-energy corrections. On the Au(110) that presents Au atoms with lower-coordination, critical in break-junction conductance measurements, we see that the HOMO level shifts further from the Fermi level. These results provide the first direct comparison of spectroscopic energy level alignment measurements with single molecule junction transport data.