Inter-Bragg crystallographic phase retrieval from shape transforms, stacking faults and substitutional disorder.

One of the brilliant ideas of John Spence when he saw the first diffraction patterns from the Linac Coherent Light Source was that one could solve the crystallographic phase problem by utilising the intensities between Bragg peaks. Because these intensities are due to the Fourier transform of the shape of the crystal, the approach came to be known as "shape-transform phasing." Shape-transform phasing was developed over the next ten years and formed the basis for many other interesting ideas and pursuits. Here we describe the current best implementation of the original idea using a lattice occupancy formalism and show that certain types of crystal defects can also be modelled via this approach, allowing the molecular structure to be recovered from the additional information offered by the inter-Bragg intensities from these crystal defects.

Joint iterative reconstruction and 3D rigid alignment for X-ray tomography.

X-ray tomography is widely used for three-dimensional structure determination in many areas of science, from the millimeter to the nanometer scale. The resolution and quality of the 3D reconstruction is limited by the availability of alignment parameters that correct for the mechanical shifts of the sample or sample stage for the images that constitute a scan. In this paper we describe an algorithm for marker-free, fully automated and accurately aligned and reconstructed X-ray tomography data. Our approach solves the tomographic reconstruction jointly with projection data alignment based on a rigid-body deformation model. We demonstrate the robustness of our method on both synthetic phantom and experimental data and show that our method is highly efficient in recovering relatively large alignment errors without prior knowledge of a low resolution approximation of the 3D structure or a reasonable estimate of alignment parameters.

Humeral Shaft Fracture Sustained During Arm Wrestling with Review of Factors Contributing to its Causation.

INTRODUCTION: Humeral shaft fractures are the most common injury sustained in arm wrestling, and its various biomechanical, anatomical, kinematic and electromyographic aspects have been studied and reported. We present a series of six cases of humeral shaft fractures in the arm wrestlers and a review of basic science studies to determine the factors contributing to their causation. MATERIALS AND METHODS: Six humeral shaft fractures associated with arm wrestling were treated between December 2018 and January 2020. The medical records and radiographs were retrospectively reviewed. In addition, the characteristics of the patients, their opponents, and the fractures were noted in a pre-designed data sheet. RESULTS: There were six men with an average age of 27.5 years (SD ± 8.9). All were amateurs who were occasional arm wrestlers. Three fractures each were sustained in the sitting and standing position, four in the losing phase, one in the winning phase, and one in the stalling phase. The dominant side humerus was involved in all but one case. The fracture types were 12-A1 (n=4); 12-B1 (n=1); 12-A2 (n=1). Three fractures were treated by open reduction and internal fixation, while three were treated conservatively with satisfactory healing. CONCLUSION: Humeral shaft fractures in arm wrestling are common in amateurs. There is no association of the fracture with the position of the players or the phase of the match. However, arm wrestlers should be aware of this complication and should receive proper guidance to reduce the risk of humeral shaft fractures.

What is the Quality of Life of Transtibial Amputees in Brunei Darussalam?

INTRODUCTION: Lower limb amputations have a profound impact on the quality of life (QoL) of the patients. This study was done to assess the QoL of patients with transtibial (below-the-knee) amputations (TTA) and transtibial amputees fitted with prosthesis. MATERIAL AND METHODS: A case-control study of patients who had undergone TTA from 2015 to 2018 was conducted in Raja Isteri Pengiran Anak Saleha Hospital (RIPAS). Complete data was available for 30 subjects and it was compared with 30 diabetic, non-amputee patients matched for age and gender. QoL was assessed using the RAND 36-Item Health Survey (SF-36) and the functional outcome of prosthesis-fitted transtibial amputees was assessed using the Houghton Scale. RESULTS: Almost all cases of TTA were a result of vascular problems related to diabetes and chronic renal disease (n=29; 97%). Eighteen (60%) participants were fitted with prosthesis and 15 (50%) reported having phantom pain. QoL of participants was found to be significantly lower than that of age and sex-matched diabetic non-amputees with regards to physical functioning, role limitation due to physical health, emotional well-being, social functioning, and bodily pain. The mean Houghton Score for participants fitted with prosthesis was 4.89 (SD= 2.83) suggesting low functional outcome. CONCLUSION: TTA has a negative impact on the QoL of patients, especially in terms of functionality. The availability of prosthesis does not significantly improve the quality of life except in the physical functioning domain. Emotional well-being should be emphasised more in the rehabilitation process as this study found poor emotional well-being among participants.

Transient Osteoporosis of the Hip: A Case Report.

Transient osteoporosis of the hip (TOH) is a benign, selflimiting condition characterised by acute onset groin pain in adults. Early diagnosis is important to differentiate it from progressive conditions such as osteonecrosis. We report on a middle-aged male who presented with right groin pain without any prior trauma. The diagnosis of transient osteoporosis of hip was confirmed by Magnetic Resonance Imaging (MRI) and he was successfully treated with a course of Alendronate sodium, anti-inflammatory analgesics and a period of non-weight bearing ambulation.

Benign Subcutaneous Emphysema of the Upper Limb: A Case Report.

Subcutaneous emphysema is the presence of gas or air in the subcutaneous tissue plane. The term is generally used to describe any soft tissue emphysema of the body wall or limbs, it can result from benign causes, most commonly secondary to trauma or from a life-threatening infection by gas gangrene or necrotising fasciitis. A case of subcutaneous emphysema involving the upper limb resulting from a trivial laceration to the elbow is reported and the importance of distinguishing between the two causes of subcutaneous emphysema is highlighted.

Simulations on time-resolved structure determination of uncrystallized biomolecules in the presence of shot noise.

Determination of fast structural changes of biomolecules is usually performed on crystalline samples in a time-resolved pump-probe experiment. Changes in the structure are found by the difference Fourier method using phases of a known reference structure. As we showed recently, such changes can also be determined from diffraction of uncrystallized molecules in random orientations. In this case, the difference in the angular correlations of the diffraction patterns is used to find structural changes. Similar to the difference Fourier method, there is no need for iterative phasing. We validated this approach previously with simulations in the absence of noise. In this paper, we show that the effects of noise can be adequately suppressed by averaging over a sufficiently large ensemble as they can be obtained using an X-ray free electron laser.

The Use of Passive Straight Leg Raising Test: A Survey of Clinicians.

INTRODUCTION: Passive Straight Leg Raising Test (PSLRT) is one of the most commonly performed test in clinical practice. The purpose of this study was to survey the practice and interpretation of PSLRT amongst clinicians working in a tertiary care hospital. METHODS: A 15 item questionnaire survey was developed covering various aspects of PSLRT. Orthopaedic surgeons(n=15), neurosurgeons (n=7) and physiotherapists (n=9)were identified as clinicians performing this test regularly and were approached to take part in the survey. RESULTS: The PSLRT was used in all cases of back and leg pain by 68% and correctly performed by 30/31. There was a wide variation in the angle at which it was considered positive (median 45 degrees; range 10-90 degrees). Only 7/31 correctly recognised reproduction of leg pain as indicative of a positive PSLRT. The sitting /distraction SLRT andwell leg / cross SLRT was performed only by 3/31 and 16/31 of clinicians respectively. 90% felt that a positive PSLRT suggested nerve root irritation and 57% thought it was due to stretch of dura and / or nerve root. 23/31 clinicians felt that PSLRT was useful or very useful and 90% reported that result of PSLRT would affect the way they treat a patient. CONCLUSIONS: PSLRT is widely used, correctly performed and felt to be useful in practice. But the interpretation of a positive test, understanding of its mechanism and useof variations is poor. There is a need to improve the interpretation and understanding of PSLRT amongst its users.

Deducing fast electron density changes in randomly orientated uncrystallized biomolecules in a pump-probe experiment.

We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump-probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes.

Vibrational Excitations and Low Energy Electronic Structure of Epoxide-decorated Graphene.

We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.

Epidemiology of burns in a major referral hospital in Brunei Darussalam.

INTRODUCTION: Burn injuries are a public health concern across the world, particularly in Southeast Asia, where epidemiological data is lacking. This retrospective study was conducted to assess the epidemiology of patients with burns treated at a major referral hospital in Brunei Darussalam, with particular reference to demographics and aetiology. METHODS: All patients were referred to and treated at the Burns Unit, where data was recorded by the on-duty nurse on a pre-designed form at the first attendance. A total of 211 patients (111 male, 100 female), comprising 10 inpatients and 201 outpatients, were treated during the study period. RESULTS: The average age of the patients was 19.6 ± 20.9 (median 10, range < 1-90) years. 67 (32%) patients were under two years of age. Scalding due to hot liquids was the most common cause (78.2%), followed by flame and contact burns. The majority of burns were sustained indoors either at home or at work (87.2%). The total body surface area (TBSA%) for the whole sample was 3.7% ± 7.9% (median 2%; range 1%-90%). Patients with flame burns (n = 19) were older and had larger TBSA% (p < 0.05). Inpatients had significantly higher TBSA% compared to outpatients (28.2% ± 26% versus 2.5% ± 2.1%; p < 0.005). CONCLUSION: Scald burns sustained indoors are the most common across all age groups. Although the TBSA is small, a large number of children are affected. There is a need for burns prevention education programme in Brunei Darussalam.

Low bone mineral density in Indian patients with fragility fractures.

OBJECTIVE: Low bone mineral density (BMD) is a major risk factor for fragility fractures in osteoporosis. In recent studies, its use with clinical risk factors has been shown to enhance prediction of fragility fractures. The present study was done to assess BMD in Indian patients with fragility fractures using digital X-ray radiogrammetry (DXR-BMD). METHODS: A total of 228 patients (64 male and 164 female) admitted to an Orthopedic Hospital for management of fragility fracture were recruited. For each patient, DXR-BMD was obtained from an anteroposterior radiograph of the non-dominant hand. RESULTS: The number of subjects with hip fracture was 104 (40 male, 64 female). Vertebral fractures were seen in 67 patients (11 male, 56 female) and distal radial fracture in 57 patients (13 male, 44 female). The DXR-BMD (g/cm(2)) was significantly lower in subjects with any fragility fracture (0.51 vs. 0.58 in men and 0.41 vs. 0.54 in women). When compared to the age-matched normative reference data by decade, all subjects with fragility fracture had significantly lower DXR-BMD except male subjects in the age decade of 40-49 years. CONCLUSION: This study confirms lower DXR-BMD in Indian subjects with fragility fractures. This may have a potential role in fracture prediction when used with clinical risk factors in the Indian population.

Melioidosis of the extremities in Brunei Darussalam.

INTRODUCTION: Melioidosis caused by Burkholderia pseudomallei is an infectious disease endemic to Southeast Asia and northern Australia. It has a broad spectrum of clinical manifestations and high mortality, and can mimic other infectious diseases. The aim of this study was to review cases of melioidosis of the extremities in Brunei Darussalam. METHODS: Culture-positive cases for Burkholderia pseudomallei in Raja Isteri Pengiran Anak Saleha Hospital were identified from records in the Microbiology Department. The case notes were reviewed to identify patients who were treated for problems affecting the extremities. 14 (13 males and one female) out of 48 patients were identified. RESULTS: The median age of the patients was 45 (range 14-55) years. Septicaemia was the most common presenting feature in 11 patients. Multisystem involvement was noted in eight patients, diabetes mellitus in nine patients and other risk factors in two patients. Blood culture was positive in ten patients and pus culture in 11 patients. The presentations noted were cellulitis of the limbs, abscess, osteomyelitis (three patients each) and septic arthritis (five patients). Orthopaedic intervention (joint washout/incision and drainage/curettage) was required in 11 patients. The median hospital stay was 27.5 (range 13-63) days; two patients required admission to intensive care. No mortality was reported. CONCLUSION: Melioidosis of the extremities is not uncommon in Brunei Darussalam. It is associated with significant morbidity, and a large number of patients require surgical intervention. Thus, a high index of suspicion is required for early diagnosis and institution of appropriate antibiotic therapy.

Can fall risk be incorporated into fracture risk assessment algorithms: a pilot study of responsiveness to clodronate.

SUMMARY: Fall risk does not significantly impact on the efficacy of the bisphosphonate clodronate in reducing the incidence of fracture. INTRODUCTION: The debate about the efficacy of skeletal therapies on fracture risk in women at increased risk of falling continues. We determined whether fall risk impeded the efficacy of clodronate to reduce osteoporotic fracture incidence. METHODS: This is a post hoc analysis of a 3-year placebo-controlled study of bisphosphonate clodronate involving 5,212 women aged 75 years or more. At entry, self-reported multiple falls in the previous month and ability to rise from a chair were documented. Their interaction with treatment efficacy was examined using Poisson regression. RESULTS: Oral doses of clodronate at 800 mg daily reduced osteoporotic fracture incidence by 24% (hazard ration (HR) 0.76, 95% confidence interval 0.63-0.93). The efficacy was similar in women with recent multiple falls compared to those without (HR 0.61 vs. 0.77, p value for interaction >0.30) or impaired ability in rising compared to those with no impairment (HR 0.79 vs. 0.74, respectively; p value > 0.30). CONCLUSION: Fall risk does not significantly impact on the anti-fracture efficacy of clodronate. If confirmed with other agents, fall risk may be incorporated into risk assessment tools designed to target skeletal therapies.

Ten-year fracture probability identifies women who will benefit from clodronate therapy--additional results from a double-blind, placebo-controlled randomised study.

UNLABELLED: Fracture risk prediction can be enhanced by the concurrent assessment of other clinical risk factors. This study demonstrates that the estimation of an individual's 10-year probability of fracture by the FRAX algorithm identifies patients at high risk of fracture who will respond to bisphosphonate therapy. INTRODUCTION: Treatments for osteoporosis are targeted largely to patients with low bone density (BMD) or a prior fragility fracture. Fracture risk prediction can be enhanced by the concurrent assessment of other clinical risk factors, but it is important to determine whether the risk so identified can be reduced by intervention. We determined the effect of a bisphosphonate on fracture rates when risk was calculated using a new risk algorithm (FRAX). METHODS: Women aged 75 years or more were recruited to a randomised, double-blind controlled trial of 800 mg oral clodronate (Bonefos) daily over 3 years. Baseline clinical risk factors were entered in the FRAX model to compute the 10-year probability of major osteoporotic fractures with or without input of femoral neck BMD. The interaction between fracture probability and treatment efficacy was examined by Poisson regression. RESULTS: In 3,974 women, the interaction between fracture probability and treatment efficacy was significant when probability was assessed without BMD (p = 0.043), but not when BMD was included (p = 0.10). Efficacy was more evident in those deemed at highest risk. For example women lying at the 75th percentile of fracture probability in the absence of BMD (10-year probability 24%) treatment reduced fracture risk by 27% (HR 0.73, 95%CI 0.58-0.92). In those with a fracture probability of 30% (90th percentile), the fracture risk reduction was 38% (HR 0.62, 0.46-0.84). CONCLUSIONS: The estimation of an individual's 10-year probability of fracture by the FRAX algorithm identifies patients at high risk of fracture who will respond to bisphosphonate therapy.

Poor knowledge about osteoporosis in learned Indian women.

OBJECTIVES: The present study was done to assess knowledge about osteoporosis in learned Indian women, identify their source of knowledge and to study the correlation of level of knowledge with other variables. METHODS: A total of 73 female staff members (average age 44.7 years) of a teaching institute completed the Osteoporosis Questionnaire (OPQ). The mean +/- SD of total score for the sample was 4.1 +/- 4.1 (range -8 to 15; maximum possible score 20). RESULTS: The correct definition of osteoporosis was given by 74%, but there was general lack of awareness in all the areas assessed. There was statistically significant difference in the total score depending on the faculty of education, with staff members from the science faculty having the maximum mean score (p < 0.05). We found no influence of age, menopausal status, previous history of fracture and family history of osteoporosis on the level of knowledge. Media (74%) was the commonest source of knowledge followed by friends (49%) and doctors (25%). CONCLUSIONS: This study highlights the general lack of knowledge about osteoporosis in learned Indian women and also the need for increased involvement of medical professionals in patient education.

Modified calcaneal index: a new screening tool for osteoporosis based on plain radiographs of the calcaneum.

PURPOSES: To assess osteoporosis using plain radiography of the calcaneum by studying the performance characteristics of the modified calcaneal index through inter- and intra-observer agreement. To study the correlation of the modified calcaneal index to quantitative ultrasound of the calcaneus and bone mineral density (BMD) of the femoral neck and distal radius. METHODS: Lateral calcaneal radiographs of 252 women who participated in a clinical trial for osteoporosis were reviewed. The BMD of the hip and distal radius was measured and the calcanea were assessed using ultrasound. The calcaneal radiographs were graded by 3 clinicians according to a previously described 5-grade calcaneal index. A modified 3-grade calcaneal index was then developed. RESULTS: The highest scores of intra- and inter-observer reliability of the modified calcaneal index were 0.45 and 0.40, respectively, which were higher than those of the 5-grade calcaneal index. The correlation of the modified calcaneal index with other measures was significant (hip BMD, r=0.31; distal radius BMD, r=0.28; calcaneal speed of sound, r=0.20; broadband ultrasound attenuation, r=0.36) [p<0.005]. There were significant differences in hip BMD, distal radial BMD, calcaneal speed of sound, and broadband ultrasound attenuation between the 3 grades of the modified calcaneal index (Kruskal-Wallis 1-way ANOVA; p<0.0001). CONCLUSION: The modified calcaneal index can be used to measure bone structure and skeletal strength and is a suitable screening tool for osteoporosis in places where advanced approaches to bone-status assessment are not available.

Application of polyaniline/sol-gel derived tetraethylorthosilicate films to an amperometric lactate biosensor.

The electrochemical entrapment of polyaniline (PANI) onto sol-gel derived tetraethylorthosilicate (TEOS) films deposited onto indium-tin-oxide (ITO) coated glass has been utilized for immobilization of lactate dehydrogenase (LDH). The performance of these sol-gel/PANI/LDH electrodes has been investigated as a function of the lactate concentration, applied potential, pH of the medium and interferents. The amperometric response of the electrodes under optimum conditions exhibited a linear relationship from 1 mM to 4 mM. An attempt has been made to extend the linearity up to 10 mM for lactate by coating an external layer of polyvinyl chloride (PVC) over the sol-gel/PANI/LDH electrodes with a correlation coefficient of 0.89. These sol-gel/PANI/LDH electrodes have a response time of about 60 s, a shelf life of about 8 weeks at 0-4 degrees C and have implications in a lactate biosensor.

Identification of toxicologically predictive gene sets using cDNA microarrays.

We have developed an approach to classify toxicants based upon their influence on profiles of mRNA transcripts. Changes in liver gene expression were examined after exposure of mice to 24 model treatments that fall into five well-studied toxicological categories: peroxisome proliferators, aryl hydrocarbon receptor agonists, noncoplanar polychlorinated biphenyls, inflammatory agents, and hypoxia-inducing agents. Analysis of 1200 transcripts using both a correlation-based approach and a probabilistic approach resulted in a classification accuracy of between 50 and 70%. However, with the use of a forward parameter selection scheme, a diagnostic set of 12 transcripts was identified that provided an estimated 100% predictive accuracy based on leave-one-out cross-validation. Expansion of this approach to additional chemicals of regulatory concern could serve as an important screening step in a new era of toxicological testing.