Association of Chest Pain with Rate Pressure Product and ST-segment Changes after Sub Arachnoid Block in Caesarean Section

When healthy women undergo caesarean section (CS) under sub arachnoid anaesthesia, transient electrocardiographic changes, such as ST-segment depression and T-wave abnormalities, are observed. During an elective caesarean section under sub arachnoid anaesthesia, about one-third of healthy parturient experience chest pain and ECG changes suggestive of myocardial ischemia. To assess the ST-segment and Rate Pressure Product changes with chest pain in patients with elective caesarean section under subarachnoid block. The Department of Anesthesia, Analgesia and Intensive Care Medicine at Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh was the site of this prospective observational study. The study included 86 healthy women between the ages of 20 and 35 who needed an elective caesarean section under a single shot sub arachnoid block and who visited the Department of Anesthesia, Analgesia, and Intensive Care Medicine at BSMMU in Shahbagh, Dhaka from January 2019 to June 2019. In comparison to the no chest pain group, ST-segment changes among the chest pain group at delivery, 5 minute, 10 minute after delivery and at the end of the surgery were highly significant (p=0.001). Comparatively, Rate Pressure Product changes were found to be significantly higher in the group with chest pain than in the group without chest pain (p=0.001). It is concluded that there is a substantial association of chest pain with rate pressure product and ST-segment changes after subarachroid block in caesarean section.

Dexmedetomidine as an Adjuvant to Bupivacaine in Caudal Analgesia in Children Undergoing Infra-Umbilical Surgery

When performing infra-umbilical procedures, caudal epidural analgesia with bupivacaine is frequently used to provide both intra- and post-operative analgesia. Dexmedetomidine, an alpha 2 agonistsare extensively used in neuraxial blocks and peripheral nerve blocks to prolong the action of bupivacaine. To find out the effects of dexmedetomidine as an adjuvant to bupivacaine for caudal analgesia in children undergoing infra-umbilical surgery. This was a randomized, controlled double-blinded prospective observational study and was performed from July 2019 to December 2019. A total of 60 (Sixty) patients with different infra-umbilical surgical problems underwent different procedure under caudal anaesthesia in different operation theatre in Bangabandhu Sheikh Mujib Medical University, Dhaka were enrolled in this study. Elaborate personal history, meticulous clinical examinations and relevant laboratory investigations was done. Post-operative adverse effects also were monitored. All information from history of illness, clinical, laboratory findings, duration of analgesia and post-operative adverse effects were recorded in a preformed data sheet (Appendix-I) and statistical analysis was done by SPSS 22.0. Mean age of the children in Group A (dexmedetomidine + bupivacaine) was 5.50±2.61 years and in Group B (bupivacaine) was 5.66±2.75. Mean weight of the children in Group A was 19.22±8.58 kg and in Group B was 19.70±8.94 kg in this study. Mean duration of anaesthesia was 27.5±6.5 minute in Group A and 28.5±5.5 minute in Group B. The mean duration of analgesia was 4.32±0.54 hours for Group A and 2.12±0.32 hours in Group B. In Group A, 46.7% patients required 1 and 3.3% required 2 rescue analgesic but in Group B, 43.3% patients required single rescue analgesic and 33.3% required two rescue analgesics (p<0.05). In Group A, 6.7% patients had nausea/ vomiting and in Group B, 16.7% patients had nausea/ vomiting (p>0.05). It can be concluded that dexmedetomidine with bupivacaine for caudal analgesia in infra-umbilical surgery significantly prolongs the duration of postoperative analgesia when compared to bupivacaine alone without any side-effects.

Predicting Difficult Intubation by using Modified Mallampati (MMT) with or without Thyromental Height Test (TMHT)

Failed Tracheal Intubation with Subsequent inability to maintain an open airway and adequate oxygenation is the most frequent cause of brain damage or death during anesthesia. Recognizing before anesthesia the potential for difficult intubation allows time for optimal preparation. Proper Selection of equipment and techniques is needed to avoid unwanted situation. To find out difficulties associated with endotracheal intubation using Modified Mallampati Test (MMT) combined with Thyromental Height Test (TMHT) and MMT without TMHT. This prospective observational study was conducted at the Department of Anesthesia in Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from April 2018 to September 2018. Two hundred two patients with different surgical procedures under general anaesthesia in different operation theaters of BSMMU, Dhaka were selected as study population. After taking written consents from each patient or his/her attendant elaborate history of illness, meticulous clinical examinations were performed and relevant laboratory investigations were done. All information was recorded in a preformed data sheet and statistical analysis was done by SPSS-22.0. Mean age ±SD of the study subjects was 42.49±14.29 years in MMT with TMHT group and 43.40±15.39 years in MMT without TMHT group. Females were enrolled more than males in both the groups. BMI was 28.75±3.59kg/m² in MMT with TMHT group and 29.44±8.64kg/m² in MMT without TMHT group. There were no significant differences in age, gender and BMI between the groups. Sensitivity, specificity, PPV, NPV and accuracy were 100.0%, 96.0%, 96.2%, 100.0% and 98.0% respectively of MMT with TMHT in predicting intubation difficulty. Sensitivity, specificity, PPV, NPV and accuracy were 100.0%, 96.0%, 96.2%, 100.0% and 98.0% respectively of MMT only in predicting intubation difficulty. MMT combined with TMHT is a better predictor of intubation difficulty than MMT alone.

Incomplete Medical Charts: Impacts And Possible Solutions

Introduction

Proper documentation and relevant updating of patients’ health status has become a cumbersome task with the inception of electronic medical records.Inpatient, ED, and ambulatory patient evaluation generate billions of records each year.It brings about a burden on the workload of the providers regarding registering and completing patients’ records.Incomplete medical records set up complications in patient management and subsequent administrative operations.Specifically, denials for reimbursement because of incomplete medical records emerge as a critical concern.Effective measures, consisting of both technical and administrative enforcements are required to reduce number of open charts.

Objectives

To understand the reasons,consequences and solutions for Incomplete/Delinquent medical records.

Methods

We searched Google scholar and Pubmed database using keywords “Incomplete medical records”, “Imapacts” and “Solutions”.Articles popped up.We selected 4 based on internal and external validity.

Results

Incomplete/Delinquent medical records are nowadays imposing a critical challenge upon financial, administrative and legal affairs in practicing Medicine.Our review shows that CMS recovery audit with hospital denials went high from 7-10% in recent years because of open/incomplete medical records.Provider’s documentation time increases as well with implementation of EHR.Appropriate measures could be taken to resolve this issue, broadly we can try two ways- training and administrative courses.

Conclusions

Physicians,residents and all respective providers should get training on a regular basis regarding EMR/EHR to complete medical records duly and effectively.The other way is administrative surveillance.If providers fail repeatedly to comply with HIM standard and complete delinquent medical records, warnings, suspensions or other regulatory actions can be executed strictly to keep them on track.

Disclosure

No significant relationships.

Measuring αβ T-Cell Receptor-Mediated Mechanosensing Using Optical Tweezers Combined with Fluorescence Imaging

T-cell antigen receptors (TCRs) are mechanosensors, which initiate a signaling cascade upon ligand recognition resulting in T-cell differentiation, homeostasis, effector and regulatory functions. An optical trap combined with fluorescence permits direct monitoring of T-cell triggering in response to force application at various concentrations of peptide-bound major histocompatibility complex molecules (pMHC). The technique mimics physiological shear forces applied as cells crawl across antigen-presenting surfaces during immune surveillance. True single molecule studies performed on single cells profile force-bond lifetime, typically seen as a catch bond, and conformational change at the TCR-pMHC bond on the surface of the cell upon force loading. Together, activation and single molecule single cell studies provide chemical and physical triggering thresholds as well as insight into catch bond formation and quaternary structural changes of single TCRs. The present methods detail assay design, preparation, and execution, as well as data analysis. These methods may be applied to a wide range of pMHC-TCR interactions and have potential for adaptation to other receptor-ligand systems.

Association of Modified Sequential Organ Failure Assessment (MSOFA) Score and C-reactive protein (CRP) With the Outcome of Patients under Mechanical Ventilation

Different scoring systems has been discovered in medical practice, more specifically for ICU treatment, are designed to objectively quantify physiologic derangements and comorbid conditions for estimating mortality, length of stay and ICU resource use. This observational and descriptive study was carried out in the ICU, BSMMU, Dhaka, during March 2014 to May 2016, to determine the association of MSOFA score, CRP level with the outcome of patients on mechanical ventilation as well as compare the MSOFA and CRP combined with MSOFA alone. For this purpose, a total of 60 critically ill patients admitted in the above hospital were included in this study. Patients with an ICU stay of less than 48 hours, readmissions not considered, known case of neuromuscular disease, connective tissue disorder, renal disease and pregnancy and Patients refused to give written consent were excluded from the study. Patients who had MSOFA ≥7, their mean duration of ICU stay were 10.9±6.7 days and mean duration of mechanical ventilation 7.63±5.2 days. Patients who had CRP >11mg/L, their mean duration of ICU stay was 10.8±7.2 days and mean duration of mechanical ventilation was 7.35±5.1 days. Patients who had MSOFA score ≥7 and CRP ≥11mg/L with mean duration of ICU stay was 10.82±7.2 days and mean duration of mechanical ventilation was 7.12±5.2 days. 69.2% patients were CRP status positive (≥11) in death group and 33.3% had alive group. 92.3% patients were Positive (CRP ≥7 or MSOFA ≥11) in death group and 14.3% had alive group. MSOFA identified true positive 32 cases for death, false positive 5 cases, false negative 7 cases and true negative 16 cases confirmed by patient's outcome. CRP level identified true positive 27 cases for death, false positive 7 cases, false negative 12 cases and true negative 14 cases confirmed by patients outcome. Combined (CRP ≥11mg/L and MSOFA score ≥7) identified true positive 33 cases for death, false positive 1 case, false negative 6 cases and true negative 20 cases confirmed by patient's outcome. We concluded that there is a positive correlation (r=0.323; p=0.014) between CRP status with MSOFA score, positive correlation (r=0.402; p=0.002) between MSOFA score with MSOFA score and CRP combined and a positive correlation (r=0.999; p=0.001) between CRP level with MSOFA score and CRP combined.

Demographic and Clinical Profile of COVID-19 ICU Patients of Bangabandhu Sheikh Mujib Medical University, Bangladesh

Corona viruses are a group of RNA viruses that cause infection in humans and animals. In human Corona viruses cause respiratory tract infections ranging from mild to critical illness. Corona virus disease 2019 (COVID-19) is caused by strain of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2). The disease was first identified in Wuhan city, of China, in December 2019 and since spread all around the world. In Bangladesh first case has been declared by Institute of Epidemiology, Disease Control and Research (IEDCR) in 8th March, 2020 and first death on 18th march in an ICU and by 13th December total 489,178 cases and 7,020 deaths occurred in this country. The main objective of this study was to determine the Demographic and Clinical Profile of COVID-19 ICU patients in Bangladesh. This retrospective descriptive study on clinical profile along with short term treatment outcomes of COVID-19 patients conducted from COVID-19 dedicated Intensive care unit of Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh during July 2020 to November 2020. Total 300 ICU patients was included in this study. The age range of the patients was from 15 to 91 years. The highest percentage of patients about 49.00%, which was 147 patients were belonged to 61-75 years age group. The patients mean age was 62.80 years. Regarding gender distribution, among those 300 patients; 77.00% which is 231 were male and only 23.00% which is 69 were female. Patients admitted with symptoms like, respiratory distress/shortness of breath (100.00%), persistent worsening cough (60.00%), fatigue (55.00%) and fever (40.00%). Patients were also present with sore throat (35.00%), rhinorrhea (30.00%), altered mental status (20.00%), diarrhoea (10.00%) and chest pain (5.00%). Regarding co-morbidities, around half of the patients were suffering from Diabetes (60.22%) and Hypertension (53.44%). Significant amount of patients were also suffering from chronic obstructive pulmonary disease (27.00%) and bronchial asthma (16.78%). Ischemic heart disease was (10.33%), chronic kidney disease (10.89%), hypothyroidism (9.78%) and multiple co-morbidities (15.12%) at the time of admission. Mortality rate in this case were 71.00% and most of the death cases were in between 61 to 75 years of age group (40.00%). After improvement 27.00% patients were transferred to cabin for further management. We could discharge to home directly only 2.00% of patients.

Single Molecule Force Spectroscopy Reveals Distinctions in Key Biophysical Parameters of αβ T-Cell Receptors Compared with Chimeric Antigen Receptors Directed at the Same Ligand

Chimeric antigen receptor (CAR) T-cell therapies exploit facile antibody-mediated targeting to elicit useful immune responses in patients. This work directly compares binding profiles of CAR and αβ T-cell receptors (TCR) with single cell and single molecule optical trap measurements against a shared ligand. DNA-tethered measurements of peptide-major histocompatibility complex (pMHC) ligand interaction in both CAR and TCR exhibit catch bonds with specific peptide agonist peaking at 25 and 14 pN, respectively. While a conformational transition is regularly seen in TCR-pMHC systems, that of CAR-pMHC systems is dissimilar, being infrequent, of lower magnitude, and irreversible. Slip bonds are observed with CD19-specific CAR T-cells and with a monoclonal antibody mapping to the MHC α2 helix but indifferent to the bound peptide. Collectively, these findings suggest that the CAR-pMHC interface underpins the CAR catch bond response to pMHC ligands in contradistinction to slip bonds for CARs targeting canonical ligands.

National Clinical Guidance for the Management of Cardiovascular Intervention in the COVID-19 Pandemic: From Bangladesh Society of Cardiovascular Interventions (BSCI)

Since the first recorded case of SARS-CoV-2 in Bangladesh on 8th March 2020, COVID-19 has spread widely through different regions of the country, resulting in a necessity to re-evaluate the delivery of cardiovascular services, particularly procedures pertaining to interventional cardiology in resource-limited settings. Given its robust capacity for human-to-human transmission and potential of being a nosocomial source of infection, the disease has specific implications on healthcare systems and health care professionals faced with performing essential cardiac procedures in patients with a suspected or confirmed diagnosis of COVID-19. The limited resources in terms of cardiac catheterization laboratories that can be designated to treat only COVID positive patients are further compounded by the additional challenges of unavailability of widespread rapid testing on-site at tertiary cardiac hospitals in Bangladesh. This document prepared for our nation by the Bangladesh Society of Cardiovascular Interventions (BSCI) is intended to serve as a clinical practice guideline for cardiovascular health care professionals, with a focus on modifying standard practice of care during the COVID-19 pandemic, in order to ensure continuation of adequate and timely treatment of cardiovascular emergencies avoiding hospital-based transmission of SARS-COV-2 among healthcare professionals and the patients. This is an evolving document based on currently available global data and is tailored to healthcare systems in Bangladesh with particular focus on, but not limited to, invasive cardiology facilities (cardiac catheterization, electrophysiology & pacing labs). This guideline is limited to the provision of cardiovascular care, and it is expected that specific targeted pharmaco-therapeutics against SARS-CoV-2 be prescribed as stipulated by the National Guidelines on Clinical Management of Corona virus Disease 2019 (COVID-19) published by the Director General of Health Services, Ministry of Health and Family Welfare of Bangladesh.

Nitrous Oxide versus Medical Air Using in General Anaesthesia During Laparoscopic Cholecystectomy: A Comparative Study

This study was designed to observe the haemodynamic changes, recovery status and cost effectiveness during anaesthesia in laparoscopic cholecystectomy with medical air in comparison to anaesthesia with nitrous oxide associated with maintain of adequate analgesia and was conducted in the department of Analgesia and Intensive Care Medicine, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2017 to June 2017. Nitrous oxide is popularly using as an analgesic in current balanced general anesthesia in addition carrier agent for anesthetic. Intraoperative pain intensity depends on many variables including, type of surgery, surgical stimulation and surgical incision. It is difficult to measure intraoperative pain properly under general anesthesia therefore anesthetist depends on the surrogate marker of inadequate analgesia like raised heart rate, blood pressure, sweating and lacrimation. However, unfortunately, these parameters may changes in same direction with light plane of anesthesia, hypercarbia and ongoing procedural status of the patient.

Self-Assembly of Amphiphiles into Vesicles and Fibrils: Investigation of Structure and Dynamics Using Spectroscopy and Microscopy Techniques

Amphiphiles are a class of molecules which are known to assemble into a variety of nanostructures. The understanding and applications of self-assembled systems are based on what has been learned from biology. Among the vast number of self-assemblies, in this article, we have described the formation, characterization, and dynamics of two important biologically inspired assemblies: vesicles and fibrils. Vesicles, which can be classified into several categories depending on the sizes and components, are of great interest due to their potential applications in drug delivery and as nanoscale reactors. The structure and dynamics of vesicles can also mimic the complex geometry of the cell membrane. On the other hand, the self-assembly of proteins, peptides, and even single amino acids leads to a number of degenerative disorders. Thus, a complete understanding of these self-assembled systems is necessary. In this article, we discuss recent work on vesicular aggregates composed of phospholipids, fatty acids, and ionic as well as nonionic surfactants and single amino acid-based fibrils such as phenylalanine and tyrosine. Beside the characterization, we also emphasize the excited-state dynamics inside the aggregates for a proper understanding of the organization, reactivity, and heterogeneity of the aggregates.

Anomalous Dynamics in tert-Butyl Alcohol-Water and Trimethylamine N-Oxide-Water Binary Mixtures: A Femtosecond Transient Absorption Study

In this article, we have investigated the unusual dynamics of tert-butyl alcohol (TBA)-water and trimethylamine N-oxide (TMAO)-water binary mixtures using solvation dynamics as a tool. For this purpose, femtosecond transient absorption spectroscopy has been employed. Although these two molecules are isosteres to each other, a significant difference in water dynamics has been observed. The solvation times in TBA-water binary mixtures are found to be between 1.5 and 15.5 ps. On the contrary, we have observed very fast dynamics in TMAO-water binary mixtures (between 210 and 600 fs). Interestingly, unusual retardation in dynamics is observed at 0.10 mole fraction of TBA and TMAO in both the binary mixtures.

Role of Oral Clonidine Premedication on Intra-operative Haemodynamics and PONV in Laparoscopic Cholecystectomy

Laparoscopic cholecystectomy is a gold standard surgical procedure for gallbladder operation. It causes altered haemodynamic responses due to pneumoperitoneum and surgical procedure also causes high incidence of postoperative nausea &vomiting. Clonidine has been shown to reduce intraoperative haemodynamic instability. This randomized prospective single blind clinical study was designed to evaluate the efficacy of oral clonidine premedication for attenuation of haemodynamic responses associated with pneumoperitoneum & also reduce the incidence of postoperative nausea & vomiting and carried out in the department of Anaesthesia Analgesia and Intensive care Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from January 2010 to June 2010. Sixty adult patients of ASA physical status I & II scheduled for elective laparoscopic cholecystecomy were recruited for a prospective randomized single blind study. They were selected randomized into two equal groups, thirty in each group. Group A received no premedication & Group B (Clonidine) received clonidine (100μgm) orally 60 minutes before induction of anaesthesia. Pulse rate, mean arterial pressure were recorded prior to induction, 2 minutes after endotracheal intubation, before pneumoperitoneum, 10 minutes & 20 minutes after pneumoperitoneum, 10 minutes after release of carbon dioxide & 10 minutes after extubation. Patients in Group B (Clonidine) maintained greater haemodynamic stability intraoperatively compare to Group A after intubation, during pneumoperitoneum and also extubation. Pulse rate & mean arterial pressure significantly varies in Group A compare with Group B (Clonidine) at different times of intraoperative period (p<0.05). Postoperative nausea & vomiting was significantly less in Group B (Clonidine). Premedication with oral clonidine attenuates the haemodynamic responses produced by pneumoperitoneum during laparoscopic cholecystectomy and also significantly nausea and vomiting, results better patient satisfaction and cost effective.

Assessment of Difficulties Associated with Endotracheal Intubation using Modified Mallampati and Upper Lip Bite Test

This study was aimed at finding the parameters for prediction of difficulty in endotracheal intubation, that are easy to examine and that could better predict difficulty. The current observational prospective, cross sectional study was conducted in the department of Anaesthesia, Analgesia and Intensive Care Medicine, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from March 2015 to September 2015 comprising 180 patient of both sexes requiring endotracheal intubation were arranged into two groups, Group A: Modified Mallampati test Group and Group B: Modified Mallampati & upper lip bite test group (combined) Assessment of difficulty in intubation was done by Cormack & Lehane direct Laryngoscopic grading. Outcome was measured as no difficulty or difficulty in intubation. In Group A 33 cases were true positive, 15 false negative, 26 false positive, 16 true negative. In Group B 53 cases were true positive, 1 false positive, 8 false negative, 28 true negative. The validity tests for Group A for evaluation of difficult intubation were indicated by sensitivity 55.9%, Specificity 51.6%, Accuracy 54.41%, Positive predictive value 68.8% and Negative predictive value 38.1%. The values for Group-B were 86.9%, 96.6%, 90.0%, 98.1% and 77.8% respectively. Combined modified Mallampati & Upper Lip Bite Test has definite value in the diagnosis of difficulty in intubation and can be regarded as sensitive & specific test for operative discrimination of the patient.

A Comparative Study of the Influence of Sugars Sucrose, Trehalose, and Maltose on the Hydration and Diffusion of DMPC Lipid Bilayer at Complete Hydration: Investigation of Structural and Spectroscopic Aspect of Lipid-Sugar Interaction

It is well-known that sugars protect membrane structures against fusion and leakage. Here, we have investigated the interaction between different sugars (sucrose, trehalose, and maltose) and phospholipid membrane of 1,2-dimyristoyl-sn-glycero-3-phoshpocholine (DMPC) using dynamic light scattering (DLS), transmission electron microscopy (TEM), and other various spectroscopic techniques. DLS measurement reveals that the addition of sugar molecule results a significant increase of the average diameter of DMPC membrane. We have also noticed that in the presence of different sugars the rotational relaxation and solvation time of coumarin 480 (C480) and coumarin 153 (C153) surrounding DMPC membrane increases, suggesting a marked reduction of the hydration behavior at the surface of phospholipid membrane. In addition, we have also investigated the effect of sugar molecules on the lateral mobility of phospholipids. Interestingly, the relative increase in rotational, solvation and lateral diffusion is more prominent for C480 than that of C153 because of their different location in lipid bilayer. It is because of preferential location of comparatively hydrophilic probe C480 in the interfacial region of the lipid bilayer. Sugars intercalate with the phospholipid headgroup through hydrogen bonding and replace smaller sized water molecules from the membrane surface. Therefore, overall, we have monitored a comparative analysis regarding the interaction of different sugar molecules (sucrose, trehalose, and maltose) with the DMPC membrane through DLS, TEM, solvation dynamics, time-resolved anisotropy, and fluorescence correlation spectroscopy (FCS) measurements to explore the structural and spectroscopic aspect of lipid-sugar interaction.

Unveiling the Mode of Interaction of Berberine Alkaloid in Different Supramolecular Confined Environments: Interplay of Surface Charge between Nano-Confined Charged Layer and DNA

In this Article, we demonstrate a detailed characterization of binding interaction of berberine chloride (BBCl) with calf-thymus DNA (CT-DNA) in buffer solution as well as in two differently charged reverse micelles (RMs). The photophyscial properties of this alkaloid have been modulated within these microheterogeneous bioassemblies. The mode of binding of this alkaloid with DNA is of debate to date. However, fluorescence spectroscopic measurements, circular dichroism (CD) measurement, and temperature-dependent study unambiguously establish that BBCl partially intercalates into the DNA base pairs. The nonplanarity imposed by partial saturation in their structure causes the nonclassical types of intercalation into DNA. Besides the intercalation, electrostatic interactions also play a significant role in the binding between BBCl and DNA. DNA structure turns into a condensed form after encapsulation into RMs, which is followed by the CD spectra and microscopy study. The probe location and dynamics in the nanopool of the RMs depended on the electrostatic interaction between the charged surfactants and cationic berberine. The structural alteration of CT-DNA from B form to condensed form and the interplay of surface charge between RMs and DNA determine the interaction between the alkaloid and DNA in RMs. Time-resolved study and fluorescence anisotropy measurements successfully provide the binding interaction of BBCl in the nanopool of the RMs in the absence and in the presence of DNA. This study motivates us to judge further the potential applicability of this alkaloid in other biological systems or other biomimicking organized assemblies.

Solvation, rotational relaxation and fluorescence correlation spectroscopic study on ionic liquid-in-oil microemulsions containing triple-chain surface active ionic liquids (SAILs)

In this article, solvation dynamics and rotational relaxation approaches have been applied to explore the microheterogeneity of surface active ionic liquid (SAIL) containing microemulsions, i.e. [P₁₃][Tf₂N] or [N₃₁₁₁][Tf₂N]/[BHD][AOT]/[IPM].

A new strategy to prepare giant vesicles from surface active ionic liquids (SAILs): a study of protein dynamics in a crowded environment using a fluorescence correlation spectroscopic technique

A simple procedure for the preparation of giant vesicles using surface active ionic liquids (SAILs) has been provided in this paper.

Spectroscopy and Fluorescence Lifetime Imaging Microscopy To Probe the Interaction of Bovine Serum Albumin with Graphene Oxide

The interaction of graphene oxide (GO) with bovine serum albumin (BSA) in aqueous buffer solution has been investigated with various spectroscopic and imaging techniques. At single molecular resolution this interaction has been performed using fluorescence correlation spectroscopy (FCS) and fluorescence lifetime imaging microscopy (FLIM) techniques. The conformational dynamics of BSA on GO's influence have been explored by FCS and circular dichroism (CD) spectroscopy. For the FCS studies BSA was labeled covalently by a fluorophore, Alexa Fluor 488. On the addition of GO in phosphate buffer of 10 mM at pH 7.4 the diffusion time (τD) and the hydrodynamic radius (Rh) of BSA increase due to adsorption of BSA. Conformational relaxation time components of native BSA drastically vary with the addition of GO, signifying the change of conformational dynamics of BSA after addition of GO. The adsorption isotherm also indicates significant adsorption of BSA on the GO surface. Adsorption of BSA on the GO surface has shown in direct images of atomic force microscopy (AFM) and FLIM. Fluorescence quenching study of BSA with addition of GO also indicates that there is strong interaction between BSA and GO.

How does the surface charge of ionic surfactant and cholesterol forming vesicles control rotational and translational motion of rhodamine 6G perchlorate (R6G ClO₄)?

The rotational dynamics and translational diffusion of a hydrophilic organic molecule, rhodamine 6G perchlorate (R6G ClO4) in small unilamellar vesicles formed by two different ionic surfactants, cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS), with cholesterol have been investigated using fluorescence spectroscopic methods. Moreover, in this article the formation of vesicle using anionic surfactant, SDS at different cholesterol-to-surfactant molar ratio (expressed by Q value (Q = [cholesterol]/[surfactant])) has also been reported. Visual observation, dynamic light scattering (DLS) study, turbidity measurement, steady state fluorescence anisotropy (r0) measurement, and eventually microscopic images reveal the formation of small unilamellar vesicles in aqueous solution. Also, in this study, an attempt has been made to observe whether the cationic probe molecule, rhodamine 6G (R6G) experiences similar or different microenvironment in cholesterol-SDS and cholesterol-CTAB assemblies with increase in cholesterol concentration. The influence of cholesterol on rotational and translational diffusion of R6G molecules has been investigated by monitoring UV-vis absorption, fluorescence, time-resolved fluorescence anisotropy, and finally fluorescence correlation spectroscopy (FCS) measurements. In cholesterol-SDS assemblies, due to the strong electrostatic attractive interaction between the negatively charged surface of vesicle and cationic R6G molecules, the rotational and diffusion motion of R6G becomes slower. However, in cholesterol-CTAB aggregates, the enhanced hydrophobicity and electrostatic repulsion induces the migration of R6G from vesicle bilayer to aqueous phase. The experimental observations suggest that the surface charge of vesicles has a stronger influence than the hydrophobicity of the vesicle bilayer on the rotational and diffusion motion of R6G molecules.

How does bile salt penetration affect the self-assembled architecture of pluronic P123 micelles? – light scattering and spectroscopic investigations

The triblock copolymer of the type (PEO)₂₀–(PPO)₇₀–(PEO)₂₀ (P123) forms a mixed supramolecular aggregate with different bile salts, sodium deoxycholate (NaDC) and sodium taurocholate (NaTC), having different hydrophobicity.

Modulation of the aggregation properties of sodium deoxycholate in presence of hydrophilic imidazolium based ionic liquid: water dynamics study to probe the structural alteration of the aggregates

In this article, we have investigated the effect of hydrophilic 1-butyl-3-methylimidazolium tetrafluoroborate on the aggregation properties of sodium deoxycholate (NaDC).

Effect of encapsulation of curcumin in polymeric nanoparticles: how efficient to control ESIPT process?

This paper demonstrates the photophysics of curcumin inside polymeric nanoparticles (NPs), which are being recently used as targeted drug delivery vehicles. For this purpose, we have prepared three polymeric NPs by ultrasonication method from three well-defined water-insoluble random copolymers. These copolymers having various degrees of hydrophobicity were synthesized via reversible addition-fragmentation transfer (RAFT) method using styrene and three different functional monomers, namely, 2-hydroxyethyl acrylate, 4-formylphenyl acrylate, and 4-vinylbenzyl chloride. The photophysics of the curcumin molecules inside the polymeric NPs have been monitored by applying tools like steady state and time-resolved fluorescence spectroscopy. An increase in fluorescence intensity along with an increase in the lifetime values indicated a perturbation of the excited state intramolecular proton transfer (ESIPT) process of curcumin inside the polymeric NPs.

Effect of confinement on excited-state proton transfer of firefly's chromophore D-luciferin in AOT reverse micelles

Excited-state intermolecular proton transfer of D-luciferin in reverse micelles has been investigated using steady-state and time-resolved fluorescence spectroscopy measurement. The different polar cores have been chosen for the study of proton transfer dynamics in aerosol-OT (AOT) reverse micelles. It is shown that aqueous reverse micelle is the suitable environment for the photoprotolytic reaction of D-luciferin. The neutral form of the chromophore is present both in ground and excited state at W0 = 0. The proton transfer in nanometer size water pool of water/AOT/n-heptane begins at W0 = 8 and increases with increasing W0 values. However, the intermolecular excited-state proton transfer (ESPT) of D-luciferin is inhibited in nonaquous reverse micelles with DMF and DMSO as a polar core. Thus, the requirement of ESPT of D-luciferin to take place in reverse micelles consists of polar protic solvent like water as a polar core.

Hard x-ray correlation analysis as a diagnostic tool for the measurement of magnetic turbulence in tokamaks

A diagnostic has been developed for the measurement and characterization of the magnetic turbulence occurring in the core region of a tokamak. A specially shielded detector looking in the tangential direction has been employed to measure the thin target bremsstrahlung from the core plasma. The thick target bremsstrahlung from the limiter is also recorded at the same time. Auto- and cross-correlation analyses have been shown to yield, respectively, the stochasticity of the magnetic fluctuations in the core region and the consequent diffusion coefficient of the nonthermal electrons. The measured stochasticity bears a relationship with the diffusion coefficient. Data obtained from internal magnetic probes corroborate the above trend but the hard x-ray measurement data are shown to be more reliable than those obtained from magnetic probes.

Prolonged analgesia by adding midazolam and hyperbaric bupivacaine in subarachnoid block for lower uterine caesarian section

Antinociceptive effect and safety of sub-arachnoid (SAB) midazolam is well established in animals and human beings. In this randomized, prospective placebo control clinical study, we investigated the addition of 2.5mg midazolam to bupivacaine on the quality of surgical anaesthesia and duration of first analgesic in the post operative period after lower uterine caesarean section (LUCS). Sixty ASA I or II pregnant women scheduled for elective lower uterine caesarean section were selected for the study. The patients were randomly allocated to receive 2ml of 0.5% hyperbaric bupivacaine with either 0.5ml of 5% dextrose in aqua or 2.5 mg (0.5ml) midazolam. The duration of first analgesic demand, quality of anaesthesia, haemodynamic changes and neonatal condition were assessed. The duration of analgesia (the time interval in minutes between the sub-arachnoid injection and the first analgesic demand by the patient) was significantly longer in the Group II than Group I (197min vs. 112min; p<0.001). The quality of surgical anaesthesia was excellent or good throughout the surgical procedure in 90% (n = 27) of the patients in Group II (p = 0.01). Systolic Blood pressure was significantly lower in the group I at 10 min and 20 min after administration of SAB than group II (p = 0.005 and p = 0.007) but comparable at other times. Sedation level, Apgar score was comparable in both groups. No neurological deficit or other significant adverse effects were recorded. The addition of midazolam with hyperbaric low dose bupivacaine in SAB significantly improves the quality of surgical anaesthesia and prolongs the duration of analgesia without any adverse effects.

Intrathecal neostigmine for postoperatrive analgesia in caesarean section

This study was done for intrathecal adjuncts often are used to enhance small dose spinal bupivacaine anaesthesia. We designed this study to evaluate the postoperative analgesic efficacy and safety of intrathecal neostigmine. A randomized, double-blind prospective study was conducted in 90 healthy term pregnant patients scheduled to undergoing elective caesarean section using spinal anaesthesia. Women were administered 12.5 mg bupivacaine alone or with 75 microgram and 150 microgram of neostigmine as intrathecal drug. Parametric data were analyzed using ANOVA. Chi-square test was used to analyze the incidence data. Neostigmine significantly increased the duration sensory and motor block (p<0.05) and the time until for achieving discharge criteria. The addition of neostigmine produced dose-dependent nausea and vomiting and had no significant effect on haemodynamic or respiratory parameters. Addition of neostigmine to intrathecal bupivacaine extends the duration of postoperative analgesia with fewer side-effects without adverse effects on fetus following caesarean section.