Comparative study of duraplasty and non duraplasty in Chiari 1 malformation with syringomyleia our institute experience

Background: The prevalence of chiari malformation, defined as tonsillar herniations of 3 to 5 mm or greater, is estimated to be in the range of one per 1000 to one per 5000 individuals. The objective was to study the clinical presentation and outcome of ACM syrinx after foramen magnum decompression, c1 posterior arch removal duraplasty and without duraplasty.Methods: The study included 75 cases admitted with ACM with syrinx in neurosurgery ward in King George hospital, Visakhapatnam, Andhra Pradesh, India, during a period of five years.Results: Clinical improvement correlated strongly with enlargement of the subarachnoid cisterns and also correlated with reduction in size of the syrinx cavities. Postoperatively all the patients had decreased neck pain and two third of the patients had improvement in nystagmus, headache and dissociative anaesthesia in few cases.Conclusions: In the available literature, the treatment options offered for ACM syrinx are foramen magnum decompression and c1posterior arch removal, release of compression bands, which were followed in our institute also. We have compared pre-and post of MRI. Clinical improvement has been observed in 2 thirds of patient after a period of 2 year period follow up

Autonomous Navigation with Collision Avoidance using ROS

 Simultaneous navigation and mapping is a modern mapping technique. The aim of SLAM is to develop 2D environment of a location while tracking the robot’s position. This paper aims to develop ROS enabled robot with SLAM features in order to avoid collisions and navigate autonomously. A world is simulated using Gazebo and visualized using a tool called Rviz. Autonomous navigation is achieved by mapping the environment and plotting the odometry. Particle filtering is the algorithm on which SLAM works. This helps in using the odometry values to find the probable path for the robot to move whilst avoiding collision

Thiol-yne \u27Click\u27 Chemistry As a Route to Functional Lipid Mimetics

Thiol-alkyne \u27click\u27 chemistry is a modular, efficient mechanism to synthesize complex A2B 3-arm star polymers. This general motif is similar to a phospholipid where the A blocks correspond to lypophilic chains and the B block represents the polar head group. In this communication we employ thiol-yne chemistry to produce polypeptide-based A2B lipid mimetics. The utility of the thiol-yne reaction is demonstrated by using a divergent and a convergent approach in the synthesis. These polymers self-assemble in aqueous solution into spherical vesicles with a relatively narrow size distribution independent of block composition over the range studied. Using the thiol-yne convergent synthesis, we envision a modular approach to functionalize proteins or oligopeptides with lipophilic chains that can imbed seamlessly into a cell membrane

Nanowired three-dimensional cardiac patches

Engineered cardiac patches for treating damaged heart tissues after a heart attack are normally produced by seeding heart cells within three-dimensional porous biomaterial scaffolds1, 2, 3. These biomaterials, which are usually made of either biological polymers such as alginate4 or synthetic polymers such as poly(lactic acid) (PLA)5, help cells organize into functioning tissues, but poor conductivity of these materials limits the ability of the patch to contract strongly as a unit6. Here, we show that incorporating gold nanowires within alginate scaffolds can bridge the electrically resistant pore walls of alginate and improve electrical communication between adjacent cardiac cells. Tissues grown on these composite matrices were thicker and better aligned than those grown on pristine alginate and when electrically stimulated, the cells in these tissues contracted synchronously. Furthermore, higher levels of the proteins involved in muscle contraction and electrical coupling are detected in the composite matrices. It is expected that the integration of conducting nanowires within three-dimensional scaffolds may improve the therapeutic value of current cardiac patches.National Institutes of Health (U.S.) (NIH, grant GM073626)National Institutes of Health (U.S.) (NIH, grant DE13023)National Institutes of Health (U.S.) (NIH, grant DE016516)American Heart Association (Postdoctoral Fellowship)National Institutes of Health (U.S.) (Ruth L. Kirschstein National Research Service Award (no. F32GM096546)

Exploring Barriers to Medication Adherence Using COM-B Model of Behaviour Among Patients with Cardiovascular Diseases in Low- and Middle-Income Countries: A Qualitative Study.

INTRODUCTION: In 2016, cardiovascular diseases (CVDs) led to 17.9 million deaths worldwide, representing 31% of all global deaths. CVDs are the leading cause of mortality worldwide and significant barriers to achieving the sustainable development goals. Modern medicines have been significant in improving health outcomes. However, non-adherence to medication is one of the reasons behind adverse health-related outcomes among patients suffering from atherosclerotic cardiovascular disease in low- and middle-income countries. PATIENTS AND METHODS: This qualitative study was conducted at two tertiary care hospitals in India and Ghana. A total of 35 in-depth interviews were conducted with atherosclerosis cardiovascular disease (ASCVD) patients. The data were analysed thematically using the Capability Opportunity and Motivation (COM-B) framework. FINDINGS: The findings were summarised under three important broad themes of the COM-B framework: capability, opportunity and behaviour. Under capability, comprehension of disease, medication schedule, and unplanned travel affected adherence among patients. Cost of medication, insurance and access were the critical factors under opportunity, which negatively influenced medication adherence. Mood, beliefs about treatment and outcome expectations under motivation led to non-adherence among patients. Apart from these factors, some important health system factors such as health care experience and trust in the facilities and reliance on alternative medication also affected adherence in both countries. CONCLUSION: This study has highlighted that the health system factors have dominantly influenced adherence to medication in India and Ghana. In India, we found participants to be satisfied with their health care provided at the government hospitals. However, limited time for consultation, lack of well-stocked pharmacy and unclear prescription negatively influenced adherence among participants in India and Ghana. The study emphasises that the health system needs to be strengthened, and the patients' belief system needs to be explored to address the issue of medication adherence in LMICs

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Poly(Z-lysine)-Based Organogels: Effect of Interfacial Frustration on Gel Strength

A series of poly(Z-lysine)-based block copolymers were synthesized with poly(propylene oxide), poly(ethylene oxide-stat-propylene oxide), and polyhedral oligomeric silsesquioxane. These copolymers form thermoreversible gels in tetrahydrofuran with critical gel concentrations as low as 0.5 wt %. Infrared spectroscopy indicates that the peptide block adopts an antiparallel beta-sheet conformation whereby the assembly is facilitated by intermolecular H-bonding. The modulus of the gels was determined as a function of poly(Z-lysine) molecular weight and solution concentration (1-4 wt %). It was found that increasing the poly(Z-lysine) molecular weight or concentration increases gel strength and the range of linear viscoelastic response with stress. Remarkably, gel strengths as high as 220 and 348 Pa in THF and chloroform, respectively, were observed. In addition, the gel strength is highly dependent on the solvent interactions with the non-peptide block of the copolymer. We propose a model where interfacial frustration destabilizes beta-sheet assembly of peptide block, leading to weaker gel

Temperature- and pH-Responsive Self-assembly of Poly(propylene oxide)-\u3ci\u3eb\u3c/i\u3e-Poly(lysine) Block Copolymers in Aqueous Solution

A series of poly(propylene oxide)-b-poly(L-lysine) (PPO-PK) block copolymers were synthesized using Huisgen\u27s 1,3-dipolar cydoaddition, and the solution self-assembly was studied using transmission electron microscopy, circular dichroism spectroscopy, and dynamic and static light scattering techniques. In contrast to previous studies of poly(lysine)-based block copolymers, PPO-PK exhibits a significant shift in the pH associated with the helix coil transition of the poly(lysine) block, potentially a result of decreased hydrophobicity in the core PPO block. Given the proximity of the lower critical solution temperature of the PPO block, these materials exhibit both pH and temperature-responsive (i.e., schizophrenic ) self-assembly, the latter of which was interpreted in terms of changes in the second osmotic virial coefficient. Finally, the vesicle morphology obtained from these polymers was studied for the propensity in drug encapsulation and passive release