Dynamic electrical stimulation enhances the recruitment of spinal interneurons by corticospinal input

Highly varying patterns of electrostimulation (Dynamic Stimulation, DS) delivered to the dorsal cord through an epidural array with 18 independent electrodes transiently facilitate corticospinal motor responses, even after spinal injury. To partly unravel how corticospinal input are affected by DS, we introduced a corticospinal platform that allows selective cortical stimulation during the multisite acquisition of cord dorsum potentials (CDPs) and the simultaneous supply of DS. Firstly, the epidural interface was validated by the acquisition of the classical multisite distribution of CDPs and their input-output profile elicited by pulses delivered to peripheral nerves. Apart from increased EMGs, DS selectively increased excitability of the spinal interneurons that first process corticospinal input, without changing the magnitude of commands descending from the motor cortex, suggesting a novel correlation between muscle recruitment and components of cortically-evoked CDPs. Finally, DS increases excitability of post-synaptic spinal interneurons at the stimulation site and their responsiveness to any residual supraspinal control, thus supporting the use of electrical neuromodulation whenever the motor output is jeopardized by a weak volitional input, due to a partial disconnection from supraspinal structures and/or neuronal brain dysfunctions.

Stretchable surface electromyography electrode array patch for tendon location and muscle injury prevention

Surface electromyography (sEMG) can provide multiplexed information about muscle performance. If current sEMG electrodes are stretchable, arrayed, and able to be used multiple times, they would offer adequate high-quality data for continuous monitoring. The lack of these properties delays the widespread use of sEMG in clinics and in everyday life. Here, we address these constraints by design of an adhesive dry electrode using tannic acid, polyvinyl alcohol, and PEDOT:PSS (TPP). The TPP electrode offers superior stretchability (~200%) and adhesiveness (0.58 N/cm) compared to current electrodes, ensuring stable and long-term contact with the skin for recording (>20 dB; >5 days). In addition, we developed a metal-polymer electrode array patch (MEAP) comprising liquid metal (LM) circuits and TPP electrodes. The MEAP demonstrated better conformability than commercial arrays, resulting in higher signal-to-noise ratio and more stable recordings during muscle movements. Manufactured using scalable screen-printing, these MEAPs feature a completely stretchable material and array architecture, enabling real-time monitoring of muscle stress, fatigue, and tendon displacement. Their potential to reduce muscle and tendon injuries and enhance performance in daily exercise and professional sports holds great promise.

Acute Effects of Strength and Skill Training on the Cortical and Spinal Circuits of Contralateral Limb

Unilateral strength and skill training increase strength and performance in the contralateral untrained limb, a phenomenon known as cross-education. Recent evidence suggests that similar neural mechanisms might be responsible for the increase in strength and skill observed in the untrained hand after unimanual training. The aims of this study were to: investigate whether a single session of unimanual strength and skill (force-tracking) training increased strength and skill in the opposite hand; measure ipsilateral (untrained) brain (via transcranial magnetic stimulation, TMS) and spinal (via the monosynaptic reflex) changes in excitability occurring after training; measure ipsilateral (untrained) pathway-specific changes in neural excitability (via TMS-conditioning of the monosynaptic reflex) occurring after training. Participants (N = 13) completed a session of unimanual strength (ballistic isometric wrist flexions) and skill (force-tracking wrist flexions) training on two separate days. Strength increased after training in the untrained hand (p = 0.025) but not in the trained hand (p = 0.611). Force-tracking performance increased in both the trained (p = 0.007) and untrained (p = 0.010) hand. Corticospinal excitability increased after force-tracking and strength training (p = 0.027), while spinal excitability was not affected (p = 0.214). TMS-conditioned monosynaptic reflex increased after force-tracking (p = 0.001) but not strength training (p = 0.689), suggesting a possible role of polysynaptic pathways in the increase of cortical excitability observed after training. The results suggest that cross-education of strength and skill at the acute stage is supported by increased excitability of the untrained motor cortex.New & Noteworthy: A single session of isometric wrist flexion strength and skill straining increased strength and skill in the untrained limb. The excitability of the untrained motor cortex increased after strength and skill training. TMS-conditioned H-reflexes increased after skill but not strength training in the untrained hand, indicating that polysynaptic pathways in the increase of cortical excitability observed after skill training.

Spinal facilitation of descending motor input

Highly varying patterns of electrostimulation (Dynamic Stimulation, DS) delivered to the dorsal cord through an epidural array with 18 independent electrodes transiently facilitate corticospinal motor responses, even after spinal injury. To partly unravel how corticospinal input are affected by DS, we introduced a corticospinal platform that allows selective cortical stimulation during the multisite acquisition of cord dorsum potentials (CDPs) and the simultaneous supply of DS. Firstly, the epidural interface was validated by the acquisition of the classical multisite distribution of CDPs on the dorsal cord and their input-output profile elicited by pulses delivered to peripheral nerves. Apart from increased EMGs, DS selectively increased excitability of the spinal interneurons that first process corticospinal input, without changing the magnitude of commands descending from the motor cortex, suggesting a novel correlation between muscle recruitment and components of cortically-evoked CDPs. Finally, DS increases excitability of post-synaptic spinal interneurons at the stimulation site and their responsiveness to any residual supraspinal control, thus supporting the use of electrical neuromodulation whenever the motor output is jeopardized by a weak volitional input, due to a partial disconnection from supraspinal structures and/or neuronal brain dysfunctions.

Simplified Markerless Stride Detection Pipeline (sMaSDP) for Surface EMG Segmentation

To diagnose mobility impairments and select appropriate physiotherapy, gait assessment studies are often recommended. These studies are usually conducted in confined clinical settings, which may feel foreign to a subject and affect their motivation, coordination, and overall mobility. Conducting gait studies in unconstrained natural settings instead, such as the subject's Activities of Daily Life (ADL), could provide a more accurate assessment. To appropriately diagnose gait deficiencies, muscle activity should be recorded in parallel with typical kinematic studies. To achieve this, Electromyography (EMG) and kinematic are collected synchronously. Our protocol sMaSDP introduces a simplified markerless gait event detection pipeline for the segmentation of EMG signals via Inertial Measurement Unit (IMU) data, based on a publicly available dataset. This methodology intends to provide a simple, detailed sequence of processing steps for gait event detection via IMU and EMG, and serves as tutorial for beginners in unconstrained gait assessment studies. In an unconstrained gait experiment, 10 healthy subjects walk through a course designed to mimic everyday walking, with their kinematic and EMG data recorded, for a total of 20 trials. Five different walking modalities, such as level walking, ramp up/down, and staircase up/down are included. By segmenting and filtering the data, we generate an algorithm that detects heel-strike events, using a single IMU, and isolates EMG activity of gait cycles. Applicable to different datasets, sMaSDP was tested in healthy gait and gait data of Parkinson's Disease (PD) patients. Using sMaSDP, we extracted muscle activity in healthy walking and identified heel-strike events in PD patient data. The algorithm parameters, such as expected velocity and cadence, are adjustable and can further improve the detection accuracy, and our emphasis on the wearable technologies makes this solution ideal for ADL gait studies.

Evaluating Muscle Synergies With EMG Data and Physics Simulation in the Neurorobotics Platform

Although we can measure muscle activity and analyze their activation patterns, we understand little about how individual muscles affect the joint torque generated. It is known that they are controlled by circuits in the spinal cord, a system much less well-understood than the cortex. Knowing the contribution of the muscles toward a joint torque would improve our understanding of human limb control. We present a novel framework to examine the control of biomechanics using physics simulations informed by electromyography (EMG) data. These signals drive a virtual musculoskeletal model in the Neurorobotics Platform (NRP), which we then use to evaluate resulting joint torques. We use our framework to analyze raw EMG data collected during an isometric knee extension study to identify synergies that drive a musculoskeletal lower limb model. The resulting knee torques are used as a reference for genetic algorithms (GA) to generate new simulated activation patterns. On the platform the GA finds solutions that generate torques matching those observed. Possible solutions include synergies that are similar to those extracted from the human study. In addition, the GA finds activation patterns that are different from the biological ones while still producing the same knee torque. The NRP forms a highly modular integrated simulation platform allowing these in silico experiments. We argue that our framework allows for research of the neurobiomechanical control of muscles during tasks, which would otherwise not be possible.

Caudal-Rostral Progression of Alpha Motoneuron Degeneration in the SOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis

Mice with transgenic expression of human SOD1G93A are a widely used model of ALS, with a caudal-rostral progression of motor impairment. Previous studies have quantified the progression of motoneuron (MN) degeneration based on size, even though alpha (α-) and gamma (γ-) MNs overlap in size. Therefore, using molecular markers and synaptic inputs, we quantified the survival of α-MNs and γ-MNs at the lumbar and cervical spinal segments of 3- and 4-month SOD1G93A mice, to investigate whether there is a caudal-rostral progression of MN death. By 3 months, in the cervical and lumbar spinal cord, there was α-MN degeneration with complete γ-MN sparing. At 3 months, the cervical spinal cord had more α-MNs per ventral horn than the lumbar spinal cord in SOD1G93A mice. A similar spatial trend of degeneration was observed in the corticospinal tract, which remained intact in the cervical spinal cord at 3- and 4- months of age. These findings agree with the corticofugal synaptopathy model that α-MNs and CST of the lumbar spinal cord are more susceptible to degeneration in SOD1G93A mice. Hence, there is a spatial and temporal caudal-rostral progression of α-MN and CST degeneration in SOD1G93A mice.

Comparison of Serum Uric Acid Levels in Patients with Stable Chronic Obstructive Pulmonary Disease and Patients with Acute Exacerbation

Purine breakdown produces uric acid (UA) as a by-product. Serum UA levels have been reported to be higher in hypoxic people, including Chronic Obstructive Pulmonary Disease (COPD) patients. Serum UA has been suggested as a marker for impaired oxidative metabolism, and it is also thought to play a role in the prognosis and evaluation of respiratory disorders such as COPD.

AIM

To compare serum uric acid levels in patients with stable Chronic Obstructive Pulmonary Disease and in patients with acute exacerbation (AE).

MATERIAL

Study Design: An observational cross sectional comparative study was conducted which included 25 stable COPD patients and 25 patients with AE of COPD, all of them aged more than 40 years. Serum UA levels were measured and compared between the two groups.

MATERIAL AND METHODS

Patients fulfilling inclusion criteria were included in the study after taking informed written consent. Blood sample was taken in plain vial and sent to Biochemistry lab for serum UA analysis. The analysis of serum UA was done using system reagent on Beckman Coulter AU Analyser. Complete blood count, blood urea, serum creatinine, arterial blood gas and oxygen saturation were also measured.

OBSERVATION AND RESULTS

The mean serum UA in the Stable group was 6.19 mg/dL and in AE group was 7.45 mg/ dL. There was a statistically significant difference between the 2 groups in terms of serum UA levels with a p value of 0.021 and the mean serum UA level being highest in the AE group. In this study, statistically significant difference was also found between Stable and AE group in terms of mMRC grading of dyspnea (p< 0.001), Pack years (p< 0.001), pH (p=0.009), pO2 (p< 0.001) and pCO2 (p< 0.001). There was no statistically significant difference between Stable and AE group in terms of age, gender, total leucocyte count, blood urea, serum creatinine and HCO3 Conclusion: Serum UA may be a useful parameter in assessing disease severity and hypoxemia in known COPD patients and may be helpful in early intensive management. Increased serum UA levels denote poor state and bad prognosis. Since serum UA is a simple, inexpensive and readily available routine laboratory test, it can be used in risk stratification in patients with COPD and can help in early management of patients with COPD.

Planning to Minimize the Human Muscular Effort during Forceful Human-Robot Collaboration

This work addresses the problem of planning a robot configuration and grasp to position a shared object during forceful human-robot collaboration, such as a puncturing or a cutting task. Particularly, our goal is to find a robot configuration that positions the jointly manipulated object such that the muscular effort of the human, operating on the same object, is minimized while also ensuring the stability of the interaction for the robot. This raises three challenges. First, we predict the human muscular effort given a human-robot combined kinematic configuration and the interaction forces of a task. To do this, we perform task-space to muscle-space mapping for two different musculoskeletal models of the human arm. Second, we predict the human body kinematic configuration given a robot configuration and the resulting object pose in the workspace. To do this, we assume that the human prefers the body configuration that minimizes the muscular effort. And third, we ensure that, under the forces applied by the human, the robot grasp on the object is stable and the robot joint torques are within limits. Addressing these three challenges, we build a planner that, given a forceful task description, can output the robot grasp on an object and the robot configuration to position the shared object in space. We quantitatively analyze the performance of the planner and the validity of our assumptions. We conduct experiments with human subjects to measure their kinematic configurations, muscular activity, and force output during collaborative puncturing and cutting tasks. The results illustrate the effectiveness of our planner in reducing the human muscular load. For instance, for the puncturing task, our planner is able to reduce muscular load by compared to a user-based selection of object poses.

The effect of limb position on a static knee extension task can be explained with a simple spinal cord circuit model

The influence of proprioceptive feedback on muscle activity during isometric tasks is the subject of conflicting studies. We performed an isometric knee extension task experiment based on two common clinical tests for mobility and flexibility. The task was carried out at four preset angles of the knee, and we recorded from five muscles for two different hip positions. We applied muscle synergy analysis using nonnegative matrix factorization on surface electromyograph recordings to identify patterns in the data that changed with internal knee angle, suggesting a link between proprioception and muscle activity. We hypothesized that such patterns arise from the way proprioceptive and cortical signals are integrated in neural circuits of the spinal cord. Using the MIIND neural simulation platform, we developed a computational model based on current understanding of spinal circuits with an adjustable afferent input. The model produces the same synergy trends as observed in the data, driven by changes in the afferent input. To match the activation patterns from each knee angle and position of the experiment, the model predicts the need for three distinct inputs: two to control a nonlinear bias toward the extensors and against the flexors, and a further input to control additional inhibition of rectus femoris. The results show that proprioception may be involved in modulating muscle synergies encoded in cortical or spinal neural circuits.NEW & NOTEWORTHY The role of sensory feedback in motor control when limbs are held in a fixed position is disputed. We performed a novel experiment involving fixed position tasks based on two common clinical tests. We identified patterns of muscle activity during the tasks that changed with different leg positions and then inferred how sensory feedback might influence the observations. We developed a computational model that required three distinct inputs to reproduce the activity patterns observed experimentally. The model provides a neural explanation for how the activity patterns can be changed by sensory feedback.

Heterogeneity in form and function of the rat extensor digitorum longus motor unit

The motor unit comprises a variable number of muscle fibres that connect through myelinated nerve fibres to a motoneuron (MN), the central drivers of activity. At the simplest level of organisation there exist phenotypically distinct MNs that activate corresponding muscle fibre types, but within an individual motor pool there typically exists a mixed population of fast and slow firing MNs, innervating groups of Type II and Type I fibres, respectively. Characterising the heterogeneity across multiple levels of motor unit organisation is critical to understanding changes that occur in response to physiological and pathological perturbations. Through a comprehensive assessment of muscle histology and ex vivo function, mathematical modelling and neuronal tracing, we demonstrate regional heterogeneities at the level of the MN, muscle fibre type composition and oxygen delivery kinetics of the rat extensor digitorum longus (EDL) muscle. Specifically, the EDL contains two phenotypically distinct regions: a relatively oxidative medial and a more glycolytic lateral compartment. Smaller muscle fibres in the medial compartment, in combination with a greater local capillary density, preserve tissue O₂ partial pressure (PO₂) during modelled activity. Conversely, capillary supply to the lateral compartment is calculated to be insufficient to defend active muscle PO₂ but is likely optimised to facilitate metabolite removal. Simulation of in vivo muscle length change and phasic activation suggest that both compartments are able to generate similar net power. However, retrograde tracing demonstrates (counter to previous observations) that a negative relationship between soma size and C‐bouton density exists. Finally, we confirm a lack of specificity of SK3 expression to slow MNs. Together, these data provide a reference for heterogeneities across the rat EDL motor unit and re‐emphasise the importance of sampling technique.

C-bouton components on rat extensor digitorum longus motoneurons are resistant to chronic functional overload

Mammalian motor systems adapt to the demands of their environment. For example, muscle fibre types change in response to increased load or endurance demands. However, for adaptations to be effective, motoneurons must adapt such that their properties match those of the innervated muscle fibres. We used a rat model of chronic functional overload to assess adaptations to both motoneuron size and a key modulatory synapse responsible for amplification of motor output, C‐boutons. Overload of extensor digitorum longus (EDL) muscles was induced by removal of their synergists, tibialis anterior muscles. Following 21 days survival, EDL muscles showed an increase in fatigue resistance and a decrease in force output, indicating a shift to a slower phenotype. These changes were reflected by a decrease in motoneuron size. However, C‐bouton complexes remained largely unaffected by overload. The C‐boutons themselves, quantified by expression of vesicular acetylcholine transporter, were similar in size and density in the control and overload conditions. Expression of the post‐synaptic voltage‐gated potassium channel (K_V2.1) was also unchanged. Small conductance calcium‐activated potassium channels (SK3) were expressed in most EDL motoneurons, despite this being an almost exclusively fast motor pool. Overload induced a decrease in the proportion of SK3⁺ cells, however, there was no change in density or size of clusters. We propose that reductions in motoneuron size may promote early recruitment of EDL motoneurons, but that C‐bouton plasticity is not necessary to increase the force output required in response to muscle overload.

Reliability of the TMS-conditioned monosynaptic reflex in the flexor carpi radialis muscle

A subthreshold pulse of transcranial magnetic stimulation (TMS) on the motor cortex can modulate the amplitude of the monosynaptic reflex (H-reflex) elicited in the flexor carpi radialis (FCR) muscle, a method known as TMS-conditioning of the H-reflex. The purpose of this study was to establish the intersession reliability of this method over the course of three sessions. Eleven healthy participants received either peripheral nerve stimulation (PNS), TMS or a combination of the two. The intensity of the PNS stimuli was set to evoke a monosynaptic response (H-reflex) corresponding to 10 % of the maximum motor response (M_max), H_{M10 %}. The conditioning effect of TMS on the monosynaptic reflex was assessed by delivering subthreshold cortical pulses at different conditioning-test intervals (from -7 ms to 7 ms) from peripheral nerve stimulation. The first interval at which facilitation could be observed was deemed early facilitation (EF). Using intraclass correlation coefficients (ICCs), we found excellent reliability for M_max amplitudes (ICC = 0.98), H_{M10 %} amplitudes (ICC = 0.85) and TMS-conditioned H-reflexes recorded at the interval following EF (EF + 2 ms) (ICC = 0.87). Good reliability (ICCs ranging from 0.67 to 0.77) was found for the other conditioning-test intervals. We conclude that TMS-conditioned H-reflexes are reliable parameters to assess the excitability of corticospinal circuits.

Toward a Closed Loop, Integrated Biocompatible Biopolymer Wound Dressing Patch for Detection and Prevention of Chronic Wound Infections

Chronic wound infections represent a significant burden to healthcare providers globally. Often, chronic wound healing is impeded by the presence of infection within the wound or wound bed. This can result in an increased healing time, healthcare cost and poor patient outcomes. Thus, there is a need for dressings that help the wound heal, in combination with early detection of wound infections to support prompt treatment. In this study, we demonstrate a novel, biocompatible wound dressing material, based on Polyhydroxyalkanoates, doped with graphene platelets, which can be used as an electrochemical sensing substrate for the detection of a common wound pathogen, Pseudomonas aeruginosa. Through the detection of the redox active secondary metabolite, pyocyanin, we demonstrate that a dressing can be produced that will detect the presence of pyocyanin across clinically relevant concentrations. Furthermore, we show that this sensor can be used to identify the presence of pyocyanin in a culture of P. aeruginosa. Overall, the sensor substrate presented in this paper represents the first step toward a new dressing with the capacity to promote wound healing, detect the presence of infection and release antimicrobial drugs, on demand, to optimized healing.

Abstract P5-08-07: Study of diphenylamine analogs as inducers of mesenchymal to epithelial transition in breast cancer

The organization of cell cytoskeleton is altered in events of epithelial to mesenchymal transition (EMT), promotion of cell motility, and cancer metastases. EMT is associated with decreased cell-cell adhesion, downregulation of epithelial markers like E-Cadherin, cytokeratins, and occludins, and upregulation of mesenchymal markers such as N-cadherin, vimentin, and various transcription factors such as slug and ZEB. Epithelial to mesenchymal transition is also a consequence of drug resistance and is responsible for cancer metastases. Triple negative breast cancer is highly aggressive cancer and patients show poor prognosis and disease-free survival due to the lack of targeted therapy. Mitogen activated protein kinase pathway, including extracellular activated kinase ERK1/2 and ERK5, and phosphoinositide 3-kinase (PI3K) pathway are known to alter the cytoskeleton through the downstream activation of oncogenes such as FRA-1 and loss of focal adhesions. Of these pathways, the MEK5-ERK5 pathway is understudied in triple negative breast cancer TNBC, and there are few research tools available to selectively inhibit this pathway. The diphenylamine analogs were derived from the parent molecule Mekinist, a FDA approved MEK1/2 inhibitor for melanoma, and modified to gain selectivity towards MEK5. SC-1-151, a type-III allosteric inhibitor of MEK5 is a dual MEK1/2 (98.6%) and MEK5 (59%) inhibitor; the molecule inhibits cell viability and colony formation, and attenuates tumor growth.

SC-1-151 was serendipitously identified as a mesenchymal to epithelial transition activator in TNBC cell line MDA-MB-231. E-cadherin protein expression and cell morphology were examined to study MET after the treatment of MDA-MB-231 cells with different structural analogs of SC-1-151 after treatment for 5 days. The compound was further found to induce E-cadherin expression and epithelial phenotype in tamoxifen resistant estrogen positive MCF-7 cell line that underwent EMT. The compound is identified to promote this activity by targeting at least the ERK-FRA1-ZEB1 axis. Alkyl or N-Methyl piperazine substituents on the amide of ring 1 produced similar result as SC-1-151, and substituting the amide group with acid or ester also induced MET. In contrast, ortho-fluoro, para-iodo functional groups of the arene ring 2, when replaced with a meta-bromo substituent did not induce MET. We aim to test the compounds on EGF treated MDA-MB-468 cells to observe the attenuation of EGF induced EMT. Future studies will be performed to determine the specific protein interactions of the promising compounds.

Citation Format: Bhatt AB, Wright TD, Anna K, Gupta M, Chakrabarty S, Flaherty PT, Hoang V, Burow M, Cavanaugh JE. Study of diphenylamine analogs as inducers of mesenchymal to epithelial transition in breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-08-07.

Activity-Based Therapies for Repair of the Corticospinal System Injured during Development

This review presents the mechanistic underpinnings of corticospinal tract (CST) development, derived from animal models, and applies what has been learned to inform neural activity-based strategies for CST repair. We first discuss that, in normal development, early bilateral CST projections are later refined into a dense crossed CST projection, with maintenance of sparse ipsilateral projections. Using a novel mouse genetic model, we show that promoting the ipsilateral CST projection produces mirror movements, common in hemiplegic cerebral palsy (CP), suggesting that ipsilateral CST projections become maladaptive when they become abnormally dense and strong. We next discuss how animal studies support a developmental “competition rule” whereby more active/used connections are more competitive and overtake less active/used connections. Based on this rule, after unilateral injury the damaged CST is less able to compete for spinal synaptic connections than the uninjured CST. This can lead to a progressive loss of the injured hemisphere’s contralateral projection and a reactive gain of the undamaged hemisphere’s ipsilateral CST. Knowledge of the pathophysiology of the developing CST after injury informs interventional strategies. In an animal model of hemiplegic CP, promoting injured system activity or decreasing the uninjured system’s activity immediately after the period of a developmental injury both increase the synaptic competitiveness of the damaged system, contributing to significant CST repair and motor recovery. However, delayed intervention, despite significant CST repair, fails to restore skilled movements, stressing the need to consider repair strategies for other neural systems, including the rubrospinal and spinal interneuronal systems. Our interventional approaches harness neural activity-dependent processes and are highly effective in restoring function. These approaches are minimally invasive and are poised for translation to the human.

Case report on carotid body tumor

A 40 years old lady presented to us with the complaints of repeated attack of syncope with left sided neck swelling. Ultrasonography, Color Doppler study and arteriography were done which revealed a solid vascular mass in the carotid bifurcation. Mass was resected and histopathology was done. Histopathologic findings were typical of a carotid body tumour. As carotid body tumour is a rare disease. So, we are going to present this in this article.

Association of premature androgenetic alopecia and metabolic syndrome in a young Indian population

Context:

Although evidences for association of androgenetic alopecia (AGA) with metabolic syndrome (MetS) are accruing, inconclusiveness with respect to the gender specificity and differential association of MetS with increasing severity of AGA continues to persist. Furthermore, data specific to Indian settings are relatively sparse.

Aims:

The present study aimed at assessing the frequency of MetS in individuals with early AGA in Indian settings.

Settings and Design:

A case-control study was conducted at a trichology clinic in Bengaluru between April 2012 and September 2012 with a total of 85 cases of AGA and 85 age-matched controls.

Materials and Methods:

The Norwood-Hamilton classification was used to assess the grade of AGA. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Blood pressure, blood glucose, lipid parameters, and body mass index along with anthropometric measurements were assessed in all study participants.

Statistical Analysis Used:

Chi-square test was used to compare proportions between groups. Means were compared between groups using Student's t-test.

Results:

MetS was seen in a higher proportion of patients with AGA (43.5%) as compared to the control group (2.4%) and the differences were statistically significant (P < 0.001). As compared to controls, patients with AGA had higher triglycerides (P < 0.001), systolic blood pressure (P < 0.001), diastolic blood pressure (P < 0.001) along with significantly lower high-density lipoprotein cholesterol levels (P < 0.001). Severity of AGA was not associated with MetS.

Conclusions:

AGA is associated with MetS in male Indian patients aged <30 years. Studies with large sample sizes may be required to conclusively define any putative associations between AGA grades and MetS.

Percutaneous Coronary Intervention (PCI) of Chronic Total Occlusion (CTO) lesion in Bangladeshi patient population: a single center experience- In hospital and 90 days outcome

Objectives Aim of the study was to evaluate the primary in-hospital success and 90 days outcome of PCI in patients with CTO lesions, using either Bare-metal stents (BMS) or Drug Eluting Stent (DES) like Sirolimus-eluting or Paclitaxel-eluting stent. Methods Total 71 patients were included in this non-randomized prospective cohort as per the definition of CTO, from a total of 875 patients who had PCI at our center in the quantifying period. Total 92 stents were deployed in 71 patients. After the guide wire crossing and the balloon dilation, measurement of the culprit lesion were done by using Siemens QCA measuring system. Among the patients, Male: 59 and Female: 12. Mean age were for Male: 53yrs, for Female: 65yrs. Associated CAD risk factors were Dyslipidemia, High Blood pressure, Diabetes Mellitus, Positive FH for CAD and Smoking (all male). Results Our study shows 71 patients (8.1%) had CTO lesion out of total 875 PCI procedures. Among the study group; 56 (79%) were Dyslipidemic, 50 (70%) were hypertensive: 40 (56%) patients were Diabetic, 25 (42%) were all male smoker. Female patients were more obese (BMI M 26: F 27) and developed CAD in advance age. We found that the incidences of CTO lesions were more in LAD territory 27 (38%) followed by RCA 26 (37%) and LCX 18 (25%). Average length and diameter of stented vessel was greater in RCA than LAD and LCX. Stents used: BMS 34 (36.9%), Sirolimus 25 (27.2%), Paclitaxel 18 (19.6%), Biolimus 10 (10.8%) and Everolimus 5 (5.4%). Post procedural, in-hospital and 90 days out come was 100% in our present study. Conclusion Our study has revealed that PCI in patients with CTO lesion has shown good success rate in our hospital with no procedural complication both in-hospital and 90 days after, either treated with BMS or DES. DOI: http://dx.doi.org/10.3329/pulse.v5i1.20185 Pulse Vol.5 January 2011 p.19-26

General route to synthesize of metal (Ni, Co, Mn, Fe) oxide nanostructure and their optical and magnetic behaviour

Here we report a generalised way to prepare transitional metal (Ni, Co, Mn, Fe) oxide nanostructures via solvothermal route followed by controlled heat treatment. The method has been successfully involved to produce structurally uniform and well crystalline phase of the different metal (Ni, Co, Mn) oxide faceted nanoparticles and porous nanorods (Fe2O3) with highly anisotropic surfaces. The product materials were characterized by the X-ray powder diffraction and electron microscope (SEM, TEM) to investigate the structural and morphological details. Optical absorption study was carried out by UV-VIS spectrophotometer and the results are analysed on the basis of their electronic transitions of 3d shell and band energies. The details magnetic investigation was carried out by the measurement of magnetization with varying magnetic field and temperature. The observed magnetic behaviour is explained on the basis of uncompensated spins lying on the surface which is extremely anisotropic in the present systems of the synthesized materials.

Physical growth and nutritional status of Car Nicobarese and Moplah children of Andaman-Nicobar Islands in India

The objective of this cross-sectional study was to assess growth and nutritional status of Car Nicobarese children and compare it with Moplah children, who live in a similar environment. A total of 436 Car Nicobarese children and 438 Moplah children, aged 6-10 years, were selected for the study. The anthropometric measurements included stature, body weight, sitting height, bi-acromial breadth, bi-iliac breadth, mid-upper arm circumference, skinfold thickness of biceps, triceps and subscapular region. 50th percentile (median) growth curves were calculated among the studied children and compared with Centers for Disease Control and Prevention (CDC) 2000 reference. Z scores of weight for age (WAZ), height for age (HAZ) and BMI for age (BMIZ) were computed using growth references of the CDC 2000. It was observed that the Car Nicobarese children were shorter but heavier than Moplah children of both sexes all through the age range, which was also reflected in median value of anthropometric variables. Car Nicobarese children were nutritionally better compared to Moplah children based on the nutritional indices. The major differences between Car Nicobarese and Moplah children were found in their arm muscularity rather than arm adiposity. Overall, Car Nicobarese children were nutritionally in normal and better condition than Moplah children. However, present dietary change (intake of high calories and fat diet) of Car Nicobarese population may be reflected in the form of childhood obesity in the recent future, which has already been observed in their adult population.

Pathophysiological mechanisms of impaired limb use and repair strategies for motor systems after unilateral injury of the developing brain

The corticospinal tract (CST) is important for limb control. In humans, it begins developing prenatally but CST connections do not have a mature pattern until about 6 months of age and its capacity to evoke muscle contraction does not mature until mid-adolescence. An initially bilateral projection is subsequently refined, so that most ipsilateral CST connections are eliminated. Unilateral brain damage during refinement leads to bilateral developmental impairments. The damaged side develops sparse and weak contralateral spinal connections and the non-involved hemisphere maintains its ipsilateral projection to develop an aberrant bilateral spinal projection. In a kitten model of unilateral spastic cerebral palsy, we replicate key features of the CST circuit changes: robust bilateral CST projections from the non-involved hemisphere, sparse contralateral connections from the affected hemisphere, and motor impairments. We discuss the role of activity-dependent synaptic competition in development of bilateral CSTs and consider several experimental strategies for restoring a more normal pattern of CST connections from the damaged and non-involved sides. We highlight recent results stressing the importance of combined repair of CST axons, restoration of a more normal motor cortex motor representation, and key involvement of spinal cholinergic interneurons in restoring skilled motor function.

Electronic absorption spectrum of triacetylene cation for astronomical considerations

The A(2)Πg ← X(2)Πu electronic transition (4800-6000 Å) of triacetylene cation was measured in an ion trap, where the vibrational and rotational degrees of freedom were equilibrated to 25 K. The rotational profile of the origin band is predicted by a collisional-radiative rate model under conditions expected in diffuse interstellar clouds. Variation in the density of the surrounding gas, rotational temperature, and velocity dispersion are taken into account.

Endosulfan and flutamide, alone and in combination, target ovarian growth in juvenile catfish, Clarias batrachus

Juvenile Catfish(es), Clarias batrachus of 50 days post hatch (dph) were exposed to endosulfan (2.5 parts per billion [ppb]) and flutamide (33 ppb), alone and in combination for 50 days to access their impact on ovarian development. The doses used in this study were nominal considering pervious reports. Sampling was done at 100 dph to perform histology and measurement of various transcripts, estradiol-17β and aromatase activity. In general, treatments enhanced expression of ovary-specific transcription factors, steroidogenic enzymes steroidogenic acute regulatory protein and aromatases while transcripts of tryptophan hydroxylase2 (tph2) and catfish gonadotropin-releasing hormone declined in the brain of all treated groups with maximum reduction in the endosulfan group. Significant reduction of tph2 immunoreactivity in the forebrain/telencephalon-preoptic area endorsed our results. Increased number of pre-vitellogenic and less immature oocytes in the treated groups indicated hastened ovarian growth. Elevated ovarian aromatase activity and plasma estradiol-17β levels were noticed in the treated groups with maximum being in the endosulfan group. These data together demonstrate that the exposure of endosulfan causes synchronous precocious ovarian development better than flutamide, alone or in combination. Our results suggest that both endosulfan and flutamide alter ovarian growth by triggering precocious development in catfish.

Endosulfan and flutamide impair testicular development in the juvenile Asian catfish, Clarias batrachus

Endosulfan and flutamide, a widely used pesticide and a prostate cancer/infertility drug, respectively, have an increased risk of causing endocrine disruption if they reach water bodies. Though many studies are available on neurotoxicity/bioaccumulation of endosulfan and receptor antagonism of flutamide, only little is known about their impact on testicular steroidogenesis at molecular level. Sex steroids play an important role in sex differentiation of lower vertebrates including fishes. Hence, a small change in their levels caused by endocrine disruptors affects the gonadal development of aquatic vertebrates significantly. The aim of this study was to evaluate the effects of endosulfan and flutamide on testis-related transcription factor and steroidogenic enzyme genes with a comparison on the levels of androgens during critical period of catfish testicular development. We also analyzed the correlation between the above-mentioned genes and catfish gonadotropin-releasing hormone (cfGnRH)-tryptophan hydroxylase2 (tph2). The Asian catfish, Clarias batrachus males at 50 days post hatch (dph) were exposed to very low dose of endosulfan (2.5 μg/L) and flutamide (33 μg/L), alone and in combination for 50 days. The doses used in this study were far less than those used in the previous studies of flutamide and reported levels of endosulfan in surface water and sediments. Sampling was done at end of the treatments (100 dph) to perform testicular germ cell count (histology), measurements of testosterone (T) and 11-ketotestosterone (11-KT) by enzyme immunoassay and transcript quantification by quantitative real-time PCR. In general, treatments decreased the expression of several genes including testis-related transcription factors (dmrt1, sox9a and wt1), steroidogenic enzymes (11β-hsd2, 17β-hsd12 and P450c17), steroidogenic acute regulatory protein and orphan nuclear receptors (nr2c1 and Ad4BP/SF-1). In contrast, the transcripts of cfGnRH and tph2 were elevated in the brain of all treated groups with maximum elevation in the endosulfan group. However, combination of endosulfan and flutamide (E+F) treatment showed minor antagonism in a few results of transcript quantification. Levels of T and 11-KT were elevated after flutamide and E+F treatments while no change was seen in the endosulfan group signifying the effect of flutamide as an androgen receptor antagonist. All the treatments modulated testis growth by decreasing the progression of differentiation of spermatogonia to spermatocytes. Based on these results, we suggest that the exposure to endosulfan and flutamide, even at low doses, impairs testicular development either directly or indirectly at the level of brain.

Detection of hidden structures for arbitrary scales in complex physical systems

Recent decades have experienced the discovery of numerous complex materials. At the root of the complexity underlying many of these materials lies a large number of contending atomic- and largerscale configurations. In order to obtain a more detailed understanding of such systems, we need tools that enable the detection of pertinent structures on all spatial and temporal scales. Towards this end, we suggest a new method that applies to both static and dynamic systems which invokes ideas from network analysis and information theory. Our approach efficiently identifies basic unit cells, topological defects, and candidate natural structures. The method is particularly useful where a clear definition of order is lacking, and the identified features may constitute a natural point of departure for further analysis.

Detecting hidden spatial and spatio-temporal structures in glasses and complex physical systems by multiresolution network clustering

We elaborate on a general method that we recently introduced for characterizing the "natural" structures in complex physical systems via multi-scale network analysis. The method is based on "community detection" wherein interacting particles are partitioned into an "ideal gas" of optimally decoupled groups of particles. Specifically, we construct a set of network representations ("replicas") of the physical system based on interatomic potentials and apply a multiscale clustering ("multiresolution community detection") analysis using information-based correlations among the replicas. Replicas may i) be different representations of an identical static system, ii) embody dynamics by considering replicas to be time separated snapshots of the system (with a tunable time separation), or iii) encode general correlations when different replicas correspond to different representations of the entire history of the system as it evolves in space-time. Inputs for our method are the inter-particle potentials or experimentally measured two (or higher order) particle correlations. We apply our method to computer simulations of a binary Kob-Andersen Lennard-Jones system in a mixture ratio of A(80)B(20) , a ternary model system with components "A", "B", and "C" in ratios of A(88)B(7)C(5) (as in Al(88)Y(7)Fe(5) , and to atomic coordinates in a Zr(80)Pt(20) system as gleaned by reverse Monte Carlo analysis of experimentally determined structure factors. We identify the dominant structures (disjoint or overlapping) and general length scales by analyzing extrema of the information theory measures. We speculate on possible links between i) physical transitions or crossovers and ii) changes in structures found by this method as well as phase transitions associated with the computational complexity of the community detection problem. We also briefly consider continuum approaches and discuss rigidity and the shear penetration depth in amorphous systems; this latter length scale increases as the system becomes progressively rigid.

Co-development of proprioceptive afferents and the corticospinal tract within the cervical spinal cord

In maturity, skilled movements depend on coordination of control signals by descending pathways, such as the corticospinal tract (CST), and proprioceptive afferents (PAs). An important locus for this coordination is the spinal cord intermediate zone. Convergence of CST and PA terminations onto common regions leads to interactions that may underlie afferent gating and modulation of descending control signals during movements. We determined establishment of CST and PA terminations within common spinal cord regions and development of synaptic interactions in 4-week-old cats, which is before major spinal motor circuit refinement, and two ages after refinement (weeks 8, 11). We examined the influence of one or the other system on monosynaptic responses, on the spinal cord surface and locally in the intermediate zone, evoked by either CST or deep radial nerve (DRN) stimulation. DRN stimulation suppressed CST monosynaptic responses at 4 weeks, but this converted to facilitation by 8 weeks. This may reflect a strategy to limit CST movement control when it has aberrant immature connections, and could produce errant movements. CST stimulation showed delayed development of mixed suppression and facilitation of DRN responses. We found development of age-dependent overlap of PA and CST terminations where interactions were recorded in the intermediate zone. Our findings reveal a novel co-development of different inputs onto common spinal circuits and suggest a logic to CST-PA interactions at an age before the CST has established connectional specificity with spinal circuits.

Synthesis and Optical Manifestation of NiO-Silica Nanocomposite

NiO-silica nanocomposites with average diameter ranging from 2–40 nm were prepared by sol-gel method followed by the heat treatment varying from 400°C to 1000°C. The details of morphology and crystalline nature of all the as prepared samples were characterized by TEM, HRTEM, and XRD analysis. The planes obtained from SAED pattern supports the planes originated from XRD study. From the optical absorption study, it is revealed that the band gap energy of NiO can extensively be manipulated by composite formation with silica and the size variation of that nanocomposite. Absorption peak position varies almost linearly with the oxidation temperature of the samples. Photoluminescence spectroscopy reveals that NiO-silica nanocomposite, prepared at 600°C and below, shows strong emission at 3.62 eV, but the nanocomposites with bigger size greatly hinder the effect of selective emissivity.

Postnatal refinement of proprioceptive afferents in the cat cervical spinal cord

Proprioceptive afferent (PA) information is integrated with signals from descending pathways, including the corticospinal tract (CST), by spinal interneurons in the dorsal horn and intermediate zone for controlling movements. PA spinal projections, and the reflexes that they evoke, develop prenatally. The CST projects to the spinal cord postnatally, and its connections are subsequently refined. Consequently, the tract becomes effective in transmitting control signals from motor cortex to muscle. This suggests sequential development of PAs and the CST rather than co-development. In this study we determined if there was also late postnatal refinement of PA spinal connections, which would support PA-CST co-development. We examined changes in PA spinal connections at 4 weeks of age, when CST terminations are immature, at 8 weeks, after CST refinement, and at 11 weeks, when CST terminations are mature. We electrically stimulated PA afferents in the deep radial nerve. Evoked PA responses were small and not localized at 4 weeks. By 8 and 11 weeks, responses were substantially larger and maximal in laminae VI and dorsal VII. We used intramuscular injection of cholera toxin β subunit to determine the distribution of PAs from the extensor carpii radialis muscle in the cervical enlargement at the same ages as in the electrophysiological studies. We found a reduction of the distribution of PAs with age that paralleled the physiological changes. This age-related sharpening of PA spinal connections also paralleled CST development, suggesting coordinated PA-CST co-development rather than sequential development. This is likely to be important for the development of adaptive motor control.

Abstract P3-04-08: Epigenetic Changes Due to DNA Methylation in CpG Islands during Breast Cancer Progression

DNA methylation has been associated with several key events of gene regulation and to human cancer. It is not yet known how the epigenome of various populations is associated with clinical manifestations during the course of the disease. In this poster we describe a method for stratifying breast cancer patients from Indian origin using CpG island microarray from the University Healthcare Network (UHN) Toronto (human CpG island 12k microarray chip, HCGI12K). DNA samples were obtained from a prospective study cohort which consisted of 51 female primary breast cancers. All patients had been undergoing treatment in a tertiary care hospital and its associated centers in the southern part of India between 2007 and 2009. We have identified and classified the DNA methylation in CpG islands of patient samples using various clinical parameters such as age of disease onset, menopausal status, hormone receptor status and Her2 status. We present the methods to analyze the data from UHN CpG island arrays used in a high throughput methylation study in order to derive decision rules of stratifying the data into basic classes such as normal and benign conditions, and infiltrating ductal carcinoma. Results will be presented pertaining to differential methylation status of patients in different categories such as age of disease onset, menopausal status, hormone receptor status and Her2 status.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-04-08.

Socioeconomic impact on child immunisation in the districts of West Bengal, India

INTRODUCTION

Knowledge of inter-district variations in immunisation coverage and the reasons for their existence is of utmost importance in a region in which variations in the socioeconomic factors are known to have a marked influence on immunisation coverage.

METHODS

This study was based on a sample of 1,279 children aged 12-35 months. Data was obtained from the District Level Household Survey under the Reproductive and Child Health project (DLHS-RCH-2) that was conducted from 2002 to 2004. Descriptive studies and logistic regression analyses were conducted to examine the variations in immunisation coverage.

RESULTS

Approximately 54 percent of children in West Bengal were covered for immunisation. The results for receiving full immunisation varied greatly between the various districts, ranging from 23.3 percent in Murshidabad to 72.2 percent in Hugli. Low rates of coverage were found among the vulnerable groups of poor minorities, especially in rural areas. No evidence of gender differences was found. The educational level of the parents was found to have a significant influence on child immunisation coverage.

CONCLUSION

In order to improve upon the rates of child immunisation coverage in West Bengal, efforts should be concentrated on poor children from minority groups and those living in rural areas.

Growth and nutritional status of Bengali adolescent girls

OBJECTIVE

Assessment of the growth and nutritional status among healthy Bengali adolescent schoolgirls at peri-urban area.

METHODS

In this cross sectional study, sample consists of 527 school going adolescent girls, aged 10 to 18 years. The sample of the present study was collected from a peri-urban area (Duttapukur) of north 24 parganas district of West Bengal, India. Standard anthropometric measurements including linear, curvilinear and skinfold thickness were collected from each subject. Percentile curves and nutritional indices were used to determine the growth and nutritional status respectively.

RESULTS

The nature of distance curves and percentile curves of the body measurements showed a high rate of increase in 10-11 years of age group corresponding to an earlier adolescent growth spurt than average Indian girls. The adolescent girls in the current study were found to be significantly (p<0.0001) taller than Indian girls and heavier than both Indian and urban Bengali girls but slightly shorter than urban Bengali girls. They are significantly (p<0.0001) shorter and lighter than American girls, which also corresponded to 50(th) percentile curves. Age specific nutritional assessment shows different grades of malnutrition among them. Gomez's classification indicates about 60 % to 70 % adolescent girls show either moderate to mild malnutrition during their growth period. Both the indices of Waterlow's classification show least percentage of least malnutrition among the girls.

CONCLUSION

The growth pattern and nutritional status observed among adolescent girls in peri-urban situation show heterogeneity with respect to some anthropometric traits and in conformity with the growth pattern and nutritional status of urban girls.

Activity-dependent plasticity improves M1 motor representation and corticospinal tract connectivity

Motor cortex (M1) activity between postnatal weeks 5 and 7 is essential for normal development of the corticospinal tract (CST) and visually guided movements. Unilateral reversible inactivation of M1, by intracortical muscimol infusion, during this period permanently impairs development of the normal dorsoventral distribution of CST terminations and visually guided motor skills. These impairments are abrogated if this M1 inactivation is followed by inactivation of the contralateral, initially active M1, from weeks 7 to 11 (termed alternate inactivation). This later period is when the M1 motor representation normally develops. The purpose of this study was to determine the effects of alternate inactivation on the motor representation of the initially inactivated M1. We used intracortical microstimulation to map the left M1 1 to 2 mo after the end of left M1 muscimol infusion. We compared representations in the unilateral inactivation and alternate inactivation groups. Alternate inactivation converted the sparse proximal M1 motor representation produced by unilateral inactivation to a complete and high-resolution proximal-distal representation. The motor map was restored by week 11, the same age that our present and prior studies demonstrated that alternate inactivation restored CST spinal connectivity. Thus M1 motor map developmental plasticity closely parallels plasticity of CST spinal terminations. After alternate inactivation reestablished CST connections and the motor map, an additional 3 wk was required for motor skill recovery. Since motor map recovery preceded behavioral recovery, our findings suggest that the representation is necessary for recovering motor skills, but additional time, or experience, is needed to learn to take advantage of the restored CST connections and motor map.