Perceived Benefits of a Research Fellowship for Dermatology Residency Applicants: Outcomes of a Faculty-Reported Survey

Dermatology continues to represent one of the most competitive specialties for medical students to match into for residency. The number of publications reported by applicants contributes to this competitiveness. Many students hoping to obtain a dermatology residency position are completing research fellowships (RFs) prior to applying. We conducted a survey to determine if those involved in the residency selection process recommend completion of an RF and how they view the perceived benefits of RF completion.

Changes in trends of orthopedic services due to the COVID-19 pandemic: A review

As of June 10, 2022, the World Health Organization has recorded over 532 million documented coronavirus disease 2019 (COVID-19) [(Coronavirus) SARS-CoV-2] cases and almost 6.3 million deaths worldwide, which has caused strain on medical specialties globally. The aim of this review is to explore the impact that COVID-19 has had on orthopedic practices. Providers observed a rapid decline in the number of orthopedic patients’ admissions due to cancellation of elective procedures; however, emergent cases still required treatment. Various observational studies, case reports, and clinical trials were collected through a PubMed database search. Additional sources were found through Google. The search was refined to publications in English and between the years of 2019 and 2021. The keywords used were “COVID-19” and/or “Orthopedic Injuries”. Thirty-seven studies were retained. The pandemic brought on significant changes to the mechanism of injury, number of admissions, type of injuries, and patient outcomes. Mortality rates significantly increased particularly amongst patients with hip fractures and COVID-19. Road traffic injuries remained a common cause of injury and domestic injuries became more prevalent with lockdown. Social isolation negatively affected mental health resulting in several orthopedic injuries. Telehealth services and separation for COVID-positive and COVID-negative patients benefited both patients and providers. While hospitals and medical facilities are still facing COVID-19 case surges, it is important to understand how this pandemic has impacted preparation, care, and opportunities for prevention education and ongoing care.

Intrathecal morphine in combination with bupivacaine as pre-emptive analgesia in posterior lumbar fusion surgery: a retrospective cohort study

Background

The purpose of this study was to evaluate the efficacy of intrathecal morphine (ITM) in combination with bupivacaine as pre-emptive analgesia in patients undergoing posterior lumbar fusion surgery. This is in comparison with traditional opioid analgesics such as intravenous (IV) morphine.

Methods

Two groups were identified retrospectively. The first (ITM group) included patients who had general anaesthesia (GA) with low-dose spinal anaesthesia prior to induction using 1–4 mls of 0.25% bupivacaine and 0.2 mg ITM. 1 ml of 0.25% bupivacaine was administered per hour of predicted surgery time, up to a maximum of 4 ml. The insertion level for the spinal anaesthetic corresponded to the spinal level of the iliac crest line and the level at which the spinal cord terminated. The control group had GA without any spinal anaesthesia. Patients were instead administered opioid analgesia in the form of IV morphine or diamorphine. The primary outcome was the consumption of opioids administered intraoperatively and in recovery, and over the first 48 h following discharge from the post-anaesthesia care unit (PACU). Total opioid dose was measured, and a morphine equivalent dose was calculated. Secondary outcomes included visual analogue scale (VAS) pain scores in recovery and at day two postoperatively, and the length of stay in hospital.

Results

For the ITM group, the median total amount of IV morphine equivalent administered intraoperatively and in recovery, was 0 mg versus 17 mg. The median total amount morphine equivalent, administered over the first 48 h following discharge from PACU was 20 mg versus 80 mg. Both are in comparison with the control group. The median length of stay was over 1 day less and the median VAS for pain in recovery was 6 points lower. No evidence was found for a difference in the worst VAS for pain at day two postoperatively.

Conclusion

ITM in combination with bupivacaine results in a significantly decreased use of perioperative opioids. In addition, length of hospital stay is reduced and so too is patient perceived pain intensity.

Trial registration The study was approved by the ethics committee at The Robert Jones and Agnes Hunt Orthopaedic Hospital as a service improvement project (Approval no. 1617_004).

Therapeutic Strategies in Traumatic Intracranial Hemorrhage and Outcomes

BACKGROUND

 Traumatic intracranial hemorrhage (TICH) and its progression have historically resulted in poor prognosis and functional disability. Such outcomes can impact the daily lives and financial condition of patients' families as well as add burden to the health care system. This review examines the diverse therapeutic intervention that were observed in randomized clinical trials (RCT) on various outcomes. Many demographic and clinical risk factors have been identified for poor prognosis after a TICH. Among the many therapeutic strategies studied, few found to have some beneficial effect in minimizing the progression of hemorrhage and reducing the overall mortality.

METHODS

 A literature review was conducted of all relevant sources using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to include articles that were RCTs for patients aged 18 years and above to include a total of 19 articles.

RESULTS

 Across studies, many therapies have been assessed; however, only few findings including infusion of tranexamic acid (TXA), use of β-blocker, and early operative evacuation of TICH yielded favorable results. Use of steroid and blood transfusion to target higher hemoglobin levels showed evidence of adversely impacting the outcome.

CONCLUSION

 Of the many therapeutic strategies available for TICH, very few therapies have proven to be beneficial.

Timing of tracheostomy in mechanically ventilated COVID-19 patients

According to the World Health Organization as of September 16, 2021, there have been over 226 million documented cases of coronavirus disease 2019 (COVID-19), which has resulted in more than 4.6 million deaths and approximately 14% develop a more severe disease that requires respiratory assistance such as intubation. Early tracheostomy is recommended for patients that are expected to be on prolonged mechanical ventilation; however, supporting data has not yet been provided for early tracheostomies in COVID-19 patients. The aim of this study was to explore established guidelines for performing tracheostomies in patients diagnosed with COVID-19. Factors considered were patient outcomes such as mortality, ventilator-associated pneumonia, intensive care unit length of stay, complications associated with procedures, and risks to healthcare providers that performed tracheostomies. Various observational studies, meta-analyses, and systematic reviews were collected through a PubMed Database search. Additional sources were found through Google. The search was refined to publications in English and between the years of 2003 and 2021. The keywords used were “Coronavirus” and/or “guidelines'' and/or “tracheostomy” and/or “intensive care”. Twenty-three studies were retained. Due to the complex presentation of the respiratory virus COVID-19, previously established guidelines for tracheostomies had to be reevaluated to determine if these guidelines were still applicable to these critically ill ventilated patients. More specifically, medical guidelines state benefits to early tracheostomies in critically ill ventilated non-COVID-19 patients. However, after having conducted this review, the assumptions about the benefits of early tracheostomies in critically ill ventilated patients may not be appropriate for COVID-19 patients.

Experimental characterization and theoretical analysis of cell tip oscillations in directional solidification

Experiments performed in DECLIC-DSI on board the International Space Station evidenced oscillatory modes during the directional solidification of a bulk sample of succinonitrile-based transparent alloy. The interferometric data acquired during a reference experiment, V_{p}=1 μm/s and G=19 K/cm, allowed us to reconstruct the cell shape and thus measure the cell tip position, radius, and growth velocity evolution, in order to quantify the dynamics of the oscillating cells. This study completes our previous reports [Bergeon et al., Phys. Rev. Lett. 110, 226102 (2013)10.1103/PhysRevLett.110.226102; Tourret et al., Phys. Rev. E 92, 042401 (2015)10.1103/PhysRevE.92.042401; Pereda et al., Phys. Rev. E 95, 012803 (2017)10.1103/PhysRevE.95.012803] with, to our knowledge, the first complete monitoring of the geometric cell tip characteristics variations in bulk samples. The evolution of the shape, velocity, and position of the tip of the oscillating cells is associated with an evolution of the concentration field, inaccessible experimentally but mediating the diffusive interactions between the cells. The experimental results are supported by 3D phase-field simulations which evidence the existence of transversal solute fluxes between neighboring cells that play a fundamental role in the oscillation dynamics. The dynamics of oscillation of an individual cell is analyzed using a theoretical model based on classical equations of solidification through the calculation of the phase relationships between oscillation of the different tip characteristics.

Low-molecular weight vs. unfractionated heparin for prevention of venous thromboembolism in general surgery: a meta-analysis

To assess the association between low-molecular weight heparin (LMWH) and unfractionated heparin (UFH) in the prevention of venous thromboembolism (VTE) among participants undergoing general surgery. LMWH and UFH are the standard of practice in the prevention of VTE in surgery. However, in the context of general surgery, studies comparing the effectiveness of these treatments are limited. A systematic search was conducted to find studies which examined the comparative effectiveness between LMWH and UFH in the prophylaxis of VTE in the context of general surgery. The number of events of VTE in groups receiving LMWH or UFH was the primary outcome of interest, and was used to calculate odds-ratios. Amongst 33,068 participants pooled from twelve studies, the rate of VTE was 1.3% in those treated with LMWH, and 3.1% in those treated with UFH. Although there was a wide difference in rates due to clinical heterogeneity, there was no statistically significant difference between treatment effects [OR 0.77; 95% CI 0.58-1.03; p value = 0.0783; I²= 62.3%; 12 studies]. In terms of the sensitivity analysis, sources overly contributing to heterogeneity were removed. The random-effects model continued to show insignificance between LMWH and UFH in the prevention of VTE in participants undergoing general surgery [OR 0.86; 95% CI 0.69-1.08; p value = 0.2005; I²= 0%; 9 studies]. Results show an equal effectiveness in the prevention of VTE between participants undergoing general surgery in those allocated to receive LMWH to those allocated to receive UFH.

0958 The Prevalence of Depression in Children With Chronic Sleep and Respiratory Disorders

Introduction

In 2017, 13.3% of US adolescents aged 12 to 17 had at least one major depressive episode (NIMH, 2019). The risk of depression is higher in children with sleep apnea, and children with depression or anxiety have a 1.2-1.8 times higher rate of asthma related ED visits. Therefore, the purpose of this study was to determine the prevalence of depression symptoms in children with chronic disorders. We hypothesized that subjects with sleep disorders would have a higher prevalence of positive depression scores than subjects with respiratory disease, and that the prevalence would be highest in subjects with both conditions.

Methods

The Patient Health Questionnaire-9 (PHQ-9) was administered to children between the ages of 12 and 18 to screen for depression as part of a pulmonary or sleep clinic visit. Each patient’s PHQ-9 results were scored as normal, mild, moderate, or severe for levels of depression severity. Additionally, a chart review was conducted to gather their demographic and clinical data.

Results

Of a total of 87 subjects,71 (81.6%) had a respiratory disorder and 40 (46.0%) subjects had a sleep disorder. Due to the amount of overlap of respiratory and sleep disorders amongst the subjects, depression severity rather than chronic disease was chosen as the primary outcome. Using multiple linear regression, when all other factors were held constant, the average depression score increased by 5.0 when patients had a combination of asthma and obstructive sleep apnea (p-value = 0.02) and also increased by 2.4 for subjects who were female (p-value = 0.01).

Conclusion

It is important to identify depression in children with chronic illness, as it can lead to higher healthcare utilization. Additionally, as mental health status may significantly impact health outcomes for patients with chronic disease, it would be beneficial to evaluate mental health in all pediatric patients with chronic disease. However, further research is needed to investigate these associations.

Support

None

Barriers in conducting clinical trials in oncology in the developing world: A cross-sectional survey of oncologists

BACKGROUND

Several obstacles impede oncologists from performing clinical trials in the developing world. This study aimed to identify these barriers in order of importance and suggest possible remedial measures.

MATERIALS AND METHODS

Design - cross-sectional survey. Two part questionnaire capturing experience of oncologists in practice and conducting trials (Part 1) and perceived barriers pertaining to investigator (training, time), patient (strict follow-up protocol), infrastructure (funds) and professional environment (encouragement from seniors) (Part 2) were administered to oncologists in two different settings: (1) Online portal (Survey Monkey) (2) In person during a national conference (Best of American Society of Clinical Oncology). Responses were captured on a Likert scale (1-5).

RESULTS

(436/3021) 14.04% responded. A total of 313 (71.8%) had experience in conducting trials, but these were mainly industry-sponsored or small nonpractice changing studies. Lack of patient follow-up was the most significant barrier (inter quartile range [IQR] 4-5) followed by inadequate training, time and funds (IQR 2-5) and lack of encouragement (IQR 2-4) in decreasing order of frequency. Lack of adequate training was a barrier across all specialties (113 [71.97%] radiation oncologists, 71 [60.68%] medical oncologists and 73 [71.56%] surgical oncologists). More than half of the respondents without experience in clinical trials worked in academic institutions (50.48%). They perceived time constraint as a barrier more than their counterparts into private practice (175/242 [72.31%] vs. 119/177 [66.47%] respectively).

CONCLUSION

Inability to maintain patient follow-up, lack of protected time and funds, inadequate training were the most significant barriers. Most of these can be addressed.

Abstract P5-16-12: Pertuzumab and trastuzumab in combination with weekly paclitaxel delivers high pCR rates with favourable toxicity profile in neo-adjuvant treatment of Her-2 positive breast cancer

This abstract was not presented at the symposium.

Experimental observation of oscillatory cellular patterns in three-dimensional directional solidification

We present a detailed analysis of oscillatory modes during three-dimensional cellular growth in a diffusive transport regime. We ground our analysis primarily on in situ observations of directional solidification experiments of a transparent succinonitrile 0.24wt% camphor alloy performed in microgravity conditions onboard the International Space Station. This study completes our previous reports [Bergeon et al., Phys. Rev. Lett. 110, 226102 (2013)10.1103/PhysRevLett.110.226102; Tourret et al., Phys. Rev. E 92, 042401 (2015)10.1103/PhysRevE.92.042401] from an experimental perspective, and results are supported by additional phase-field simulations. We analyze the influence of growth parameters, crystal orientation, and sample history on promoting oscillations, and on their spatiotemporal characteristics. Cellular patterns display a remarkably uniform oscillation period throughout the entire array, despite a high array disorder and a wide distribution of primary spacing. Oscillation inhibition may be associated to crystalline disorientation, which stems from polygonization and is manifested as pattern drifting. We determine a drifting velocity threshold above which oscillations are inhibited, thereby demonstrating that inhibition is due to cell drifting and not directly to disorientation, and also explaining the suppression of oscillations when the pulling velocity history favors drifting. Furthermore, we show that the array disorder prevents long-range coherence of oscillations, but not short-range coherence in localized ordered regions. For regions of a few cells exhibiting hexagonal (square) ordering, three (two) subarrays oscillate with a phase shift of approximately ±120^{∘} (180^{∘}), with square ordering occurring preferentially near subgrain boundaries.

Oscillatory cellular patterns in three-dimensional directional solidification

We present a phase-field study of oscillatory breathing modes observed during the solidification of three-dimensional cellular arrays in microgravity. Directional solidification experiments conducted onboard the International Space Station have allowed us to observe spatially extended homogeneous arrays of cells and dendrites while minimizing the amount of gravity-induced convection in the liquid. In situ observations of transparent alloys have revealed the existence, over a narrow range of control parameters, of oscillations in cellular arrays with a period ranging from about 25 to 125 min. Cellular patterns are spatially disordered, and the oscillations of individual cells are spatiotemporally uncorrelated at long distance. However, in regions displaying short-range spatial ordering, groups of cells can synchronize into oscillatory breathing modes. Quantitative phase-field simulations show that the oscillatory behavior of cells in this regime is linked to a stability limit of the spacing in hexagonal cellular array structures. For relatively high cellular front undercooling (i.e., low growth velocity or high thermal gradient), a gap appears in the otherwise continuous range of stable array spacings. Close to this gap, a sustained oscillatory regime appears with a period that compares quantitatively well with experiment. For control parameters where this gap exists, oscillations typically occur for spacings at the edge of the gap. However, after a change of growth conditions, oscillations can also occur for nearby values of control parameters where this gap just closes and a continuous range of spacings exists. In addition, sustained oscillations at to the opening of this stable gap exhibit a slow periodic modulation of the phase-shift among cells with a slower period of several hours. While long-range coherence of breathing modes can be achieved in simulations for a perfect spatial arrangement of cells as initial condition, global disorder is observed in both three-dimensional experiments and simulations from realistic noisy initial conditions. In the latter case, erratic tip-splitting events promoted by large-amplitude oscillations contribute to maintaining the long-range array disorder, unlike in thin-sample experiments where long-range coherence of oscillations is experimentally observable.

Investigation of prolonged hypobaric hypoxia-induced change in rat brain using T2 relaxometry and diffusion tensor imaging at 7T

The present study examines the change in water diffusion properties of the corpus callosum (CC) and the hippocampus, in response to prolonged hypobaric hypoxia (HH) stress, using in vivo magnetic resonance imaging (MRI) modalities such as T2 relaxometry and diffusion tensor imaging (DTI). Three groups of rats (n=7/group) were exposed to a simulated altitude of 6700m above sea level for the duration of 7, 14 and 21days, respectively. Data were acquired pre-exposure, post-exposure and after 1week of normoxic follow-up in each group. The increment in T2 values with no apparent diffusion coefficient (ADC) change in the CC after 7 and 14days of HH exposure indicated mixed (vasogenic and cytotoxic) edema formation. After 1week of normoxia, 7-day HH-exposed rats showed a decrease in ADC values in the CC, probably due to cytotoxic edema. A delayed decrease in ADC values was observed in the hippocampus after 1week normoxic follow-up in 7- and 14-day HH groups giving an insight of cytotoxic edema formation. Interestingly, 21-day HH-exposed rats did not show change in ADC values. The decrease in T2 values after 14 and 21days in the hippocampal region depicts iron deposition, which was confirmed by histopathology. This study successfully demonstrated the use of MRI modality to trace water diffusion changes in the brain due to prolonged HH exposure.

Diffusion tensor tractography in hypothyroidism and its correlation with memory function

Diffusion tensor tractography (DTT) was performed to determine the microstructural changes in the white matter fibre tracts of hypothyroid patients compared to controls and to correlate these changes with memory dysfunction scores. DTT and Postgraduate Institute Memory Scale test were performed in eight hypothyroid patients and eight healthy controls. Diffusion tensor imaging (DTI) measures [fractional anisotropy (FA) and mean diffusivity (MD)] from all of the major cerebral tracts were calculated and a comparison was made between the patient group and controls. Pearson's correlation was performed between Memory Dysfunction score and DTI measures. Significant changes in DTI measures were observed in various white matter fibre tracts in hypothyroid patients compared to controls. In hypothyroid patients, an inverse correlation of Memory Dysfunction score with FA was observed in the right and left inferior fronto-occipital fasciculus, whereas a positive correlation with MD was observed in the right anterior thalamic radiation among all white matter tracts. These findings suggest that microstructural changes in white matter fibres may contribute to the underlying dysfunction in memory in hypothyroid patients.

Demyelinating evidences in CMS rat model of depression: a DTI study at 7 T

Depression is among the most debilitating diseases worldwide. Long-term exposure to stressors plays a major role in development of human depression. Chronic mild stress (CMS) seems to be a valid animal model for depression. Diffusion tensor imaging (DTI) is capable of inferring microstructural abnormalities of the white matter and has shown to serve as non-invasive marker of specific pathology. We developed a CMS rat model of depression and validated with behavioral experiments. We measured the diffusion indices (mean diffusivity (MD), fractional anisotropy (FA), axial (λ∥) and radial (λ⊥) diffusivity) to investigate the changes in CMS rat brain during depression onset. Diffusion indices have shown to be useful to discriminate myelin damage from axon loss. DTI was performed in both control and CMS rats (n=10, in each group) and maps of FA, MD, λ∥ and λ⊥ diffusivity values were generated using in-house built software. The diffusion indices were calculated by region of interest (ROI) analysis in different brain regions like the frontal cortex, hippocampus, hypothalamus, cingulum, thalamus, caudate putamen, corpus callosum, cerebral peduncle and sensory motor cortex. The results showed signs of demyelination, reflected by increased MD, decreased FA and increased λ⊥. The results also suggest a possible role of edema or inflammation concerning the brain morphology in CMS rats. The overall finding using DTI suggests there might be a major role of loss of myelin sheath, which leads to disrupted connectivity between the limbic area and the prefrontal cortex during the onset of depression. Our findings indicate that interpretation of these indices may provide crucial information about the type and severity of mood disorders.

A linguistically informed autosomal STR survey of human populations residing in the greater Himalayan region

The greater Himalayan region demarcates two of the most prominent linguistic phyla in Asia: Tibeto-Burman and Indo-European. Previous genetic surveys, mainly using Y-chromosome polymorphisms and/or mitochondrial DNA polymorphisms suggested a substantially reduced geneflow between populations belonging to these two phyla. These studies, however, have mainly focussed on populations residing far to the north and/or south of this mountain range, and have not been able to study geneflow patterns within the greater Himalayan region itself. We now report a detailed, linguistically informed, genetic survey of Tibeto-Burman and Indo-European speakers from the Himalayan countries Nepal and Bhutan based on autosomal microsatellite markers and compare these populations with surrounding regions. The genetic differentiation between populations within the Himalayas seems to be much higher than between populations in the neighbouring countries. We also observe a remarkable genetic differentiation between the Tibeto-Burman speaking populations on the one hand and Indo-European speaking populations on the other, suggesting that language and geography have played an equally large role in defining the genetic composition of present-day populations within the Himalayas.

miR-542-3p suppresses osteoblast cell proliferation and differentiation, targets BMP-7 signaling and inhibits bone formation

MicroRNAs (miRNAs) are short non-coding RNAs that interfere with translation of specific target mRNAs and thereby regulate diverse biological processes. Recent studies have suggested that miRNAs might have a role in osteoblast differentiation and bone formation. Here, we show that miR-542-3p, a well-characterized tumor suppressor whose downregulation is tightly associated with tumor progression via C-src-related oncogenic pathways, inhibits osteoblast proliferation and differentiation. miRNA array profiling in Medicarpin (a pterocarpan with proven bone-forming effects) induced mice calvarial osteoblast cells and further validation by quantitative real-time PCR revealed that miR-542-3p was downregulated during osteoblast differentiation. Over-expression of miR-542-3p inhibited osteoblast differentiation, whereas inhibition of miR-542-3p function by anti-miR-542-3p promoted expression of osteoblast-specific genes, alkaline phosphatase activity and matrix mineralization. Target prediction analysis tools and experimental validation by luciferase 3′ UTR reporter assay identified BMP-7 (bone morphogenetic protein 7) as a direct target of miR-542-3p. It was seen that over-expression of miR-542-3p leads to repression of BMP-7 and inhibition of BMP-7/PI3K- survivin signaling. This strongly suggests that miR-542-3p suppresses osteogenic differentiation and promotes osteoblast apoptosis by repressing BMP-7 and its downstream signaling. Furthermore, silencing of miR-542-3p led to increased bone formation, bone strength and improved trabecular microarchitecture in sham and ovariectomized (Ovx) mice. Although miR-542-3p is known to be a tumor repressor, we have identified second complementary function of miR-542-3p where it inhibits BMP-7-mediated osteogenesis. Our findings suggest that pharmacological inhibition of miR-542-3p by anti-miR-542-3p could represent a therapeutic strategy for enhancing bone formation in vivo.

Withaferin A: a proteasomal inhibitor promotes healing after injury and exerts anabolic effect on osteoporotic bone

Withania somnifera or Ashwagandha is a medicinal herb of Ayurveda. Though the extract and purified molecules, withanolides, from this plant have been shown to have different pharmacological activities, their effect on bone formation has not been studied. Here, we show that one of the withanolide, withaferin A (WFA) acts as a proteasomal inhibitor (PI) and binds to specific catalytic β subunit of the 20S proteasome. It exerts positive effect on osteoblast by increasing osteoblast proliferation and differentiation. WFA increased expression of osteoblast-specific transcription factor and mineralizing genes, promoted osteoblast survival and suppressed inflammatory cytokines. In osteoclast, WFA treatment decreased osteoclast number directly by decreasing expression of tartarate-resistant acid phosphatase and receptor activator of nuclear factor kappa-B (RANK) and indirectly by decreasing osteoprotegrin/RANK ligand ratio. Our data show that in vitro treatment of WFA to calvarial osteoblast cells decreased expression of E3 ubiquitin ligase, Smad ubiquitin regulatory factor 2 (Smurf2), preventing degradation of Runt-related transcription factor 2 (RunX2) and relevant Smad proteins, which are phosphorylated by bone morphogenetic protein 2. Increased Smurf2 expression due to exogenous treatment of tumor necrosis factor α (TNFα) to primary osteoblast cells was decreased by WFA treatment. This was corroborated by using small interfering RNA against Smurf2. Further, WFA also blocked nuclear factor kappa-B (NF-kB) signaling as assessed by tumor necrosis factor stimulated nuclear translocation of p65-subunit of NF-kB. Overall data show that in vitro proteasome inhibition by WFA simultaneously promoted osteoblastogenesis by stabilizing RunX2 and suppressed osteoclast differentiation, by inhibiting osteoclastogenesis. Oral administration of WFA to osteopenic ovariectomized mice increased osteoprogenitor cells in the bone marrow and increased expression of osteogenic genes. WFA supplementation improved trabecular micro-architecture of the long bones, increased biomechanical strength parameters of the vertebra and femur, decreased bone turnover markers (osteocalcin and TNFα) and expression of skeletal osteoclastogenic genes. It also increased new bone formation and expression of osteogenic genes in the femur bone as compared with vehicle groups (Sham) and ovariectomy (OVx), Bortezomib (known PI), injectible parathyroid hormone and alendronate (FDA approved drugs). WFA promoted the process of cortical bone regeneration at drill-holes site in the femur mid-diaphysis region and cortical gap was bridged with woven bone within 11 days of both estrogen sufficient and deficient (ovariectomized, Ovx) mice. Together our data suggest that WFA stimulates bone formation by abrogating proteasomal machinery and provides knowledge base for its clinical evaluation as a bone anabolic agent.

Spatiotemporal dynamics of oscillatory cellular patterns in three-dimensional directional solidification

We report results of directional solidification experiments conducted on board the International Space Station and quantitative phase-field modeling of those experiments. The experiments image for the first time in situ the spatially extended dynamics of three-dimensional cellular array patterns formed under microgravity conditions where fluid flow is suppressed. Experiments and phase-field simulations reveal the existence of oscillatory breathing modes with time periods of several 10's of minutes. Oscillating cells are usually noncoherent due to array disorder, with the exception of small areas where the array structure is regular and stable.

Isoformononetin, a methoxydaidzein present in medicinal plants, reverses bone loss in osteopenic rats and exerts bone anabolic action by preventing osteoblast apoptosis

PURPOSE

Daidzein (Daid) has been implicated in bone health for its estrogen-'like' effects but low bioavailability, unfavorable metabolism and uterine estrogenicity impede its clinical potential. This study was aimed at assessing isoformononetin (Isoformo), a naturally occurring methoxydaidzein, for bone anabolic effect by overcoming the pitfalls associated with Daid.

METHODS

Sprague-Dawley ovariectomized (OVx) rats with established osteopenia were administered Isoformo, 17β-oestradiol (E2) or human parathyroid hormone. Efficacy was evaluated by bone microarchitecture using microcomputed tomography and determination of new bone formation by fluorescent labeling of bone. Osteoblast apoptosis was measured by co-labeling of bone sections with Runx-2 and TUNEL. Biochemical markers of bone metabolism were measured by ELISA. Plasma and bone marrow levels of Isoformo and Daid were determined by LC-MS-MS. Rat bone marrow stromal cells were harvested to study osteoblastic differentiation by Isoformo and Daid. New born rat pups were injected with Isoformo and Daid to study the effect of the compounds on the expression of osteogenic genes in the calvaria by real time PCR.

RESULTS

In osteopenic rats, Isoformo treatment restored trabecular microarchitecture, increased new bone formation, increased the serum osteogenic marker (procollagen N-terminal propeptide), decreased resorptive marker (urinary C-terminal teleopeptide of type I collagen) and diminished osteoblast apoptosis in bone. At the most effective osteogenic dose of Isoformo, plasma and bone marrow levels were comprised of ~90% Isoformo and the rest, Daid. Isoformo at the concentration reaching the bone marrow achieved out of its most effective oral dosing induced stromal cell mineralization and osteogenic gene expression in the calvaria of neonatal rats. Isoformo exhibited uterine safety.

CONCLUSIONS

Our study demonstrates that Isoformo reverses established osteopenia in adult OVx rats likely via its pro-survival effect on osteoblasts. Given its bone anabolic and anti-catabolic effects accompanied with safety at uterine level we propose its potential in the management of postmenopausal osteoporosis.

Correlation of quantitative diffusion tensor tractography with clinical grades of subacute sclerosing panencephalitis

BACKGROUND AND PURPOSE

SSPE is a persistent infection of the central nervous system caused by the measles virus. The correlation between the clinical staging and conventional MR imaging is usually poor. The purpose of this study was to determine whether tract-specific DTI measures in the major white mater tracts correlate with clinical grades as defined by the Jabbour classification for SSPE.

MATERIALS AND METHODS

Quantitative DTT was performed on 20 patients with SSPE (mean age, 9 years) and 14 age- and sex-matched controls. All patients were graded on the basis of the Jabbour classification into grade II (n=9), grade III (n=6), and grade IV (n=5) SSPE. The major white matter tracts quantified included the CC, SLF, ILF, CST, CNG, SCP, MCP, ICP, ATR, STR, and PTR.

RESULTS

Although a successive decrease in mean FA values was observed in all the fiber tracts except for the SCP and ICP, moving from controls to grade IV, a significant inverse correlation between clinical grade and mean FA values was observed only in the splenium (r=-0.908, P<.001), CST (r=-0.663, P=.013), SLF (r=-0.533, P=.050), ILF (r=-0.776, P=.001), STR (r=-0.538, P=.047), and PTR (r=-0.686, P=.035) fibers. No significant correlation of mean MD values from these white matter tracts was observed with clinical grades of the disease.

CONCLUSIONS

We conclude that the grade of encephalopathy correlates inversely with the tract-specific mean FA values. This information may be valuable in studying the disease progression with time and in assessing the therapeutic response in the future.

Anabolics in osteoporosis: the emerging therapeutic tool

Anabolic therapy for osteoporosis has become the most desirable therapeutic option for menopausal osteoporosis. The anabolic agents currently in clinical use are reviewed. Teriparatide (recombinant human 1-34 parathyroid hormone) is used to treat women with menopausal osteoporosis and men at high risk for fractures. Despite PTH's clinical use, the mechanism underlying its anabolic action requires greater elucidation. Proteol (strontium ranelate) acts by inhibiting bone resorption and presumably promoting bone formation. Though clinical trials have shown that strontium ranelate reduces the frequency of both vertebral and non-vertebral fractures, its molecular target remains controversial. Lately, with the discontinuation of estrogen replacement therapy, phytoestrogens are gaining much attention, chiefly as prophylactic agents. Though ipriflavone stimulates osteoblast function in vitro and favorably influences bone turnover and spinal bone mineral density in peri- and postmenopausal women, its clinical use is currently rather limited. As with PTH and strontium ranelate, the mode of action of ipriflavone requires much greater elucidation. Since osteoporosis therapies are long-term, safety is a major consideration. PTH has been reported to be associated with incidence of osteosarcoma and strontium ranelate with DRESS syndrome. Therefore, target-based (and osteoblast-specific) development of molecules is expected to improve the safety profile of anabolics. Calcium-sensing receptor, insulin-like growth factor-1, members of wingless tail signaling family, and sclerostin are emerging concepts in bone anabolic therapy. We will cover the preclinical development of some bone anabolic agents under active investigation.

Diffusion tensor MR imaging in children with pantothenate kinase-associated neurodegeneration with brain iron accumulation and their siblings

BACKGROUND AND PURPOSE

It has been reported that iron concentration influences DTI metrics in deep gray matter nuclei. We hypothesized that increased FA in the deep gray nuclei may indicate abnormal iron accumulation in patients with PKAN and their siblings.

MATERIALS AND METHODS

Seven patients with the characteristic "eye-of-the-tiger sign," their 5 siblings, and 5 age-matched controls were prospectively studied. One-way ANOVA with Bonferroni post hoc multiple comparisons was used to compare DTI metrics (FA and MD) among subject groups in the putamen, CN, GP, SN, and ALIC. In addition, hypointense and hyperintense regions of the eye-of-the-tiger sign were segmented, and their DTI metrics were compared. In the patient group, the values of DTI metrics in hypointense regions were also compared with those of the ALIC.

RESULTS

A significant increase in FA values of the GP and SN from controls to the patient group to siblings was observed. In the GP, MD values were significantly higher in patients compared with controls and siblings. The patients showed significantly increased FA with decreased MD in hypointense compared with hyperintense regions of the eye-of-the-tiger sign. No difference in FA values were observed between the ALIC and hypointense regions of the eye-of-the-tiger sign in patients.

CONCLUSIONS

High FA values in siblings of patients with PKAN suggest the presence of abnormal iron in deep gray matter nuclei, even in the absence of its demonstration on T2*-weighted GRE.

Antiquity, geographic contiguity and genetic affinity among Tibeto-Burman populations of India: A microsatellite study

BACKGROUND

The Tibeto-Burman (TB) populations are one of the four major linguistic population groups of India. They are considered belonging to different stocks and show wide variation in culture and language; however, their genetic relationship, antiquity and migration history among the regional populations has been little investigated. Molecular genetic studies are expected to clearly show the antiquity and genetic diversity of these populations.

AIM

This paper seeks to understand the extent and magnitude of genetic affinities and diversities among 14 TB populations (12 Indian and two global groups), investigate the findings based on classical genetic markers and verify the historical accounts of their migration and genetic history based on 12 microsatellite markers.

SUBJECTS AND METHODS

The allele frequency data for 12 STR loci of 13 Asian (Tibeto-Burman) populations were obtained from the literature and the Adi Pasi data was obtained by microsatellite typing of their blood samples. The 12 loci studied are D5S818, FGA, D8S1179, D21S11, D7S820, CSF1PO, D3S1358, THO1, D13S317, vWa, TPOX, D18S51. Three different distance measures, two phylogenetic trees and PCA plot have been employed to understand the genetic relationship of the studied populations.

RESULTS

Average heterozygosity values range from 68 to 79% and the average G(ST) value is 4.7%. The dendrogram, based on the D(A) distance, shows the clustering of populations based on their diversities and geographical contiguity; the Mizoram and Arunachal Pradesh populations especially cluster together, populations from Sikkim form a separate subcluster and Manipur populations along with the Garo of West Bengal separate out from the other clusters. The Harpending and Ward regression model shows isolated populations positioned below the regression line and others, who experience external gene flow, placed above the line. The results support folklore migration accounts of their possible antiquity with the Tibetan and southern Chinese populations.

CONCLUSIONS

Overall, geographic contiguity, punctuated by isolating barriers, is a major influencing factor of genetic affinity among the TB population; contiguous populations within a region show greater genetic relationship than with distant TB populations over a wide geographical area. The results of the microsatellite study also support the history of diverse routes of migration of these populations.

Characterisation of carotid atheroma in symptomatic and asymptomatic patients using high resolution MRI

BACKGROUND AND PURPOSE

To prospectively evaluate differences in carotid plaque characteristics in symptomatic and asymptomatic patients using high resolution MRI.

METHODS

20 symptomatic and 20 asymptomatic patients, with at least 50% carotid stenosis as determined by Doppler ultrasound, underwent preoperative in vivo multispectral MRI of the carotid arteries. Studies were analysed both qualitatively and quantitatively in a randomised manner by two experienced readers in consensus, blinded to clinical status, and plaques were classified according to the modified American Heart Association (AHA) criteria.

RESULTS

After exclusion of poor quality images, 109 MRI sections in 18 symptomatic and 19 asymptomatic patients were available for analysis. There were no significant differences in mean luminal stenosis severity (72.9% vs 67.6%; p = 0.09) or plaque burden (median plaque areas 50 mm(2) vs 50 mm(2); p = 0.858) between the symptomatic and asymptomatic groups. However, symptomatic lesions had a higher incidence of ruptured fibrous caps (36.5% vs 8.7%; p = 0.004), haemorrhage or thrombus (46.5% vs 14.0%; p<0.001), large necrotic lipid cores (63.8% vs 28.0%; p = 0.002) and complicated type VI AHA lesions (61.5% vs 28.1%; p = 0.001) compared with asymptomatic lesions. The MRI findings of plaque haemorrhage or thrombus had an odds ratio of 5.25 (95% CI 2.08 to 13.24) while thin or ruptured fibrous cap (as opposed to a thick fibrous cap) had an odds ratio of 7.94 (95% CI 2.93 to 21.51) for prediction of symptomatic clinical status.

CONCLUSIONS

There are significant differences in plaque characteristics between symptomatic and asymptomatic carotid atheroma and these can be detected in vivo by high resolution MRI.

Deep vein thrombosis associated with osteomyelitis

Three children developed deep vein thrombosis (DVT) along with osteomyelitis of the femur. Although DVT was recognized early, the diagnosis of associated osteomyelitis was delayed due to overlapping clinical signs and the absence of radiological changes in the initial X-rays.