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1.
ACS Pharmacol Transl Sci ; 4(4): 1338-1348, 2021 Aug 13.
Article in English | MEDLINE | ID: mdl-34423270

ABSTRACT

Elevated islet production of prostaglandin E2 (PGE2), an arachidonic acid metabolite, and expression of prostaglandin E2 receptor subtype EP3 (EP3) are well-known contributors to the ß-cell dysfunction of type 2 diabetes (T2D). Yet, many of the same pathophysiological conditions exist in obesity, and little is known about how the PGE2 production and signaling pathway influences nondiabetic ß-cell function. In this work, plasma arachidonic acid and PGE2 metabolite levels were quantified in a cohort of nondiabetic and T2D human subjects to identify their relationship with glycemic control, obesity, and systemic inflammation. In order to link these findings to processes happening at the islet level, cadaveric human islets were subject to gene expression and functional assays. Interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) mRNA levels, but not those of EP3, positively correlated with donor body mass index (BMI). IL-6 expression also strongly correlated with the expression of COX-2 and other PGE2 synthetic pathway genes. Insulin secretion assays using an EP3-specific antagonist confirmed functionally relevant upregulation of PGE2 production. Yet, islets from obese donors were not dysfunctional, secreting just as much insulin in basal and stimulatory conditions as those from nonobese donors as a percent of content. Islet insulin content, on the other hand, was increased with both donor BMI and islet COX-2 expression, while EP3 expression was unaffected. We conclude that upregulated islet PGE2 production may be part of the ß-cell adaption response to obesity and insulin resistance that only becomes dysfunctional when both ligand and receptor are highly expressed in T2D.

2.
Indian J Med Res ; 153(3): 253-255, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33906986
3.
Pharmacol Res Perspect ; 9(2): e00736, 2021 04.
Article in English | MEDLINE | ID: mdl-33694300

ABSTRACT

Chronic elevations in fatty acid metabolites termed prostaglandins can be found in circulation and in pancreatic islets from mice or humans with diabetes and have been suggested as contributing to the ß-cell dysfunction of the disease. Two-series prostaglandins bind to a family of G-protein-coupled receptors, each with different biochemical and pharmacological properties. Prostaglandin E receptor (EP) subfamily agonists and antagonists have been shown to influence ß-cell insulin secretion, replication, and/or survival. Here, we define EP3 as the sole prostanoid receptor family member expressed in a rat ß-cell-derived line that regulates glucose-stimulated insulin secretion. Several other agonists classically understood as selective for other prostanoid receptor family members also reduce glucose-stimulated insulin secretion, but these effects are only observed at relatively high concentrations, and, using a well-characterized EP3-specific antagonist, are mediated solely by cross-reactivity with rat EP3. Our findings confirm the critical role of EP3 in regulating ß-cell function, but are also of general interest, as many agonists supposedly selective for other prostanoid receptor family members are also full and efficacious agonists of EP3. Therefore, care must be taken when interpreting experimental results from cells or cell lines that also express EP3.


Subject(s)
Glucose/metabolism , Insulin Secretion/physiology , Receptors, Prostaglandin E, EP3 Subtype/metabolism , Animals , Cell Line, Tumor , Drug Evaluation, Preclinical/methods , Insulin Secretion/drug effects , Insulin-Secreting Cells , Rats , Receptors, Prostaglandin E, EP3 Subtype/antagonists & inhibitors
4.
Metabolites ; 11(1)2021 Jan 16.
Article in English | MEDLINE | ID: mdl-33467110

ABSTRACT

The transition from ß-cell compensation to ß-cell failure is not well understood. Previous works by our group and others have demonstrated a role for Prostaglandin EP3 receptor (EP3), encoded by the Ptger3 gene, in the loss of functional ß-cell mass in Type 2 diabetes (T2D). The primary endogenous EP3 ligand is the arachidonic acid metabolite prostaglandin E2 (PGE2). Expression of the pancreatic islet EP3 and PGE2 synthetic enzymes and/or PGE2 excretion itself have all been shown to be upregulated in primary mouse and human islets isolated from animals or human organ donors with established T2D compared to nondiabetic controls. In this study, we took advantage of a rare and fleeting phenotype in which a subset of Black and Tan BRachyury (BTBR) mice homozygous for the Leptinob/ob mutation-a strong genetic model of T2D-were entirely protected from fasting hyperglycemia even with equal obesity and insulin resistance as their hyperglycemic littermates. Utilizing this model, we found numerous alterations in full-body metabolic parameters in T2D-protected mice (e.g., gut microbiome composition, circulating pancreatic and incretin hormones, and markers of systemic inflammation) that correlate with improvements in EP3-mediated ß-cell dysfunction.

5.
Indian J Med Res ; 151(6): 550-553, 2020 06.
Article in English | MEDLINE | ID: mdl-32719227

ABSTRACT

There is a great interest among various international agencies/countries in developing partnership with Indian research organizations, particularly with the Indian Council of Medical Research (ICMR) for biomedical research. The ICMR is actively involved in governance and co-ordination of partnerships with several international organizations and agencies. Various MoUs (Memorandum of Understanding)/agreements of ICMR with international partners bring together the researchers and resources towards progression through shared research and innovation agenda. Growing collaboration during recent years is reflected through increased number of internationally funded/technically coordinated research projects in health research. However, for any international collaborative research study to be undertaken in India, certain regulatory requirements are to be fulfilled. This article summarizes the international partnerships of ICMR as well as the details of guidelines regarding submission of international collaborative research projects for the Health Ministry's Screening Committee (HMSC), which is a mandatory requirement before undertaking such projects.


Subject(s)
Biomedical Research , Humans , India , International Cooperation
6.
Saudi J Anaesth ; 12(2): 272-278, 2018.
Article in English | MEDLINE | ID: mdl-29628839

ABSTRACT

BACKGROUND: The aim of the study was to compare the ease the intubation using GlideScope video laryngoscope and Macintosh laryngoscope in adult patients undergoing elective surgery under general anesthesia. MATERIALS AND METHODS: A total of 200 American Society of Anesthesiologists I-II patients of either sex, in the age group of 18-60 years were included in the study. Patients were randomly allocated to two groups. We assessed ease of intubation depending on time to tracheal intubation, number of attempts, glottic view (Cormack-Lehane grade [CL grade] and percentage of glottis opening [POGO]) and intubation difficulty score (IDS), hemodynamic variables and any intra- and post-operative adverse events. RESULTS: The rate of successful endotracheal intubation (ETI) in both groups was 100% in the first attempt. The time required for successful ETI was 24.89 ± 5.574 in Group G and 20.68 ± 3.637 in Group M (P < 0.001) found to be statistically significant. There was significant improvement in glottic view with GlideScope (as assessed by POGO score 66.71 ± 29.929 and 94.40 ± 10.476 in group G and 75.85 ± 26.969 and 74.20 ± 29.514 Group M and CL grading [P < 0.001]). A comparison of mean IDS between two groups revealed intubation was easier with the use of GlideScope. The hemodynamic response to intubation was significantly lesser with the use of GlideScope when compared with Macintosh laryngoscope. The incidence of adverse events, though minor like superficial lip or tongue bleed, was similar in two groups. CONCLUSIONS: GlideScope offers superiority over Macintosh laryngoscope in terms of laryngeal views and the difficulty encountered at ETI in an unselected population.

7.
J Pharm Sci ; 107(1): 372-379, 2018 01.
Article in English | MEDLINE | ID: mdl-28923318

ABSTRACT

The objective of the study was to select solid-state plasticizers for hot-melt extrusion (HME) process. The physical and mechanical properties of plasticizers, in selected binary (polymer:plasticizer) and ternary (active pharmaceutical ingredient:polymer:plasticizer) systems, were evaluated to assess their effectiveness as processing aids for HME process. Indomethacin and Eudragit® E PO were selected as model active pharmaceutical ingredient and polymer, respectively. Solubility parameters, thermal analysis, and rheological evaluation were used as assessment tools. Based on comparable solubility parameters, stearic acid, glyceryl behenate, and polyethylene glycol 8000 were selected as solid-state plasticizers. Binary and ternary physical mixtures were evaluated as a function of plasticizer concentration for thermal and rheological behavior. The thermal and rheological assessments also confirmed the miscibility predictions from solubility parameters. The understanding of thermal and rheological properties of the various mixtures helped in predicating plasticization efficiency of stearic acid, glyceryl behenate, and polyethylene glycol 8000. The evaluation also provided insight into the properties of the final product. An empirical model was also developed correlating rheological property of physical mixtures to actual HME process. Based on plasticizer efficiency, solid-state plasticizers and processing conditions can be selected for a HME process.


Subject(s)
Plasticizers/chemistry , Fatty Acids/chemistry , Hot Temperature , Indomethacin/chemistry , Polyethylene Glycols/chemistry , Polymers/chemistry , Polymethacrylic Acids/chemistry , Rheology/methods , Solubility/drug effects , Stearic Acids/chemistry , Technology, Pharmaceutical/methods
8.
J Immunol ; 200(3): 1220-1226, 2018 02 01.
Article in English | MEDLINE | ID: mdl-29288205

ABSTRACT

Following activation, T cells rapidly divide and acquire effector functions. This energetically demanding process depends upon the ability of T cells to undergo metabolic remodeling from oxidative phosphorylation to aerobic glycolysis, during which glucose is converted into lactate and released extracellularly. In this article, we demonstrate that extracellular lactate can be used to dynamically assess human T cell responses in vitro. Extracellular lactate levels strongly correlated with T cell proliferation, and measuring lactate compared favorably with traditional methods for determining T cell responses (i.e., [3H]thymidine incorporation and the use of cell proliferation dyes). Furthermore, we demonstrate the usefulness of measuring lactate as a read-out in conventional suppression assays and high-throughput peptide-screening assays. Extracellular lactate was stably produced over 7 d, and results were reproducibly performed over several freeze-thaw cycles. We conclude that the use of extracellular lactate measurements can be a sensitive, safe, stable, and easy-to-implement research tool for measuring T cell responses and cellular metabolic changes in vitro.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cell Proliferation/physiology , Lactic Acid/analysis , Cells, Cultured , Cytomegalovirus/immunology , Glycolysis/physiology , Humans , Lactic Acid/metabolism , Lymphocyte Activation/immunology , Oxidative Phosphorylation , Viral Proteins/immunology
9.
J Clin Diagn Res ; 11(7): XD03-XD05, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28893026

ABSTRACT

Breast carcinoma is the most common invasive cancer in women worldwide. It metastasizes commonly to bone, lungs, regional lymph nodes and brain. Cardiac metastasis of lung and breast cancers is a known but rare complication of advanced disease with tumour metastasising to pericardium via the locoregional lymphatic system. Here we present a case of 59-year-old female presenting with right upper limb oedema, facial puffiness and features of Superior Vena Cava (SVC) syndrome 15 years after mastectomy and adjuvant chemotherapy, radiotherapy for carcinoma of the right breast. Further evaluation revealed extensive thrombus invading the right internal jugular vein, subclavian vein, SVC with intraluminal extension into right atrium causing ball in a loop obstruction at tricuspid valve. Whole body Positron emission tomography scan confirmed the diagnosis of extensive metastatic disease and patient was managed on palliative therapy. Haematogenous spread and intraluminal growth of metastatic deposits from breast carcinoma 15 years ago is rare and clinical presentation as SVC obstruction has not been reported in our review of literature.

10.
J Clin Diagn Res ; 11(5): OD22-OD23, 2017 May.
Article in English | MEDLINE | ID: mdl-28658837

ABSTRACT

Acute Aorto-Iliac Occlusive Disease (AIOD) is a rare clinical entity which when presents with buttock claudication, erectile dysfunction and absent femoral pulses is termed as Leriche syndrome. A 59-year-old male patient with past history of smoking and dyslipidaemia presented with acute onset lower back pain, paraplegia, intense lower limb pain and was initially evaluated for compressive myelopathy. On further clinical examination there were absent femoral pulses and Computed Tomography (CT) aortogram was done which confirmed the diagnosis of diffuse AIOD. Clinically, it is often challenging to differentiate between vascular or neurogenic origin of acute onset painful paraplegia. A high index of suspicion and careful clinical examination is therefore essential to avoid misdiagnosis of a major vascular event which can result in significant morbidity and mortality.

11.
Acta Med Acad ; 46(2): 105-115, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29338274

ABSTRACT

OBJECTIVE: To investigate the frequency and uniqueness of different lip print patterns, fingerprint patterns in relation to gender and ABO Rh blood groups among a semi-urban population of Sriganganagar, Rajasthan. MATERIALS AND METHODS: The study was conducted on 1200 healthy volunteers aged 18-30 years. The cheiloscopic and dermatographic data of each subject were obtained and were analysed according to the Suzuki and Tsuchihashi and Henry systems of classification, respectively. Two forensic experts analyzed the patterns independently. The ABO Rh blood group was also recorded for each subject. The Chi square statistical analysis was done and tests were considered significant when p value <0.001 and Cohen kappa test was applied to analyze inter-observer reliability. RESULTS: The B+ blood group was noted as most common in both genders while least common were A- among males and AB- in females. Type II lip pattern was most predominant while the least common was Type I' in males and Type I' and Type V in females. The UL fingerprint pattern was the most common, while RL was least noted in both genders. All the fingerprint patterns showed correlation with different lip print patterns. A correlation was found between different blood groups and lip print patterns except Type I (vertical) lip pattern. A positive correlation was observed between all the blood groups and fingerprint patterns, except for RL pattern. CONCLUSION: There is an association between lip print patterns, fingerprint patterns and ABO blood groups in both the genders. Thus, correlating the uniqueness of these physical evidences sometimes helps the forensic team members in accurate personal identification or it can at least narrow the search for an individual where there are no possible data referring to the identity of the subject.


Subject(s)
Biometric Identification , Blood Group Antigens , Dermatoglyphics , Lip , Adolescent , Adult , Blood Grouping and Crossmatching , Chi-Square Distribution , Female , Forensic Medicine , Humans , India , Male , Records , Young Adult
12.
J Cyst Fibros ; 16(1): 70-77, 2017 01.
Article in English | MEDLINE | ID: mdl-27515017

ABSTRACT

BACKGROUND: Increased patient longevity and aggressive antibiotic treatment are thought to impact on the microbial composition of the airways of adults with cystic fibrosis (CF). In this study, we sought to determine if a temporal change in the airway microbiology of adults with CF has occurred over time. METHODS: Longitudinal analysis of sputum microbiology results was undertaken on patients attending a large adult CF centre. Clinical status and health outcomes of transitioning patients were also assessed. RESULTS: A decrease in the prevalence of Pseudomonas aeruginosa, Staphylococcus aureus, Burkholderia cepacia complex and Aspergillus spp. (p=0.001, p<0.001, p=0.002 and p<0.001, respectively) occurred. Improvements in lung function among transitioning patients infected with P. aeruginosa were observed. CONCLUSION: Overtime, a decline in the prevalence of many CF airway pathogens has occurred. Significantly, an incremental improvement in lung function was reported for transitioning patients with current P. aeruginosa infections.


Subject(s)
Burkholderia Infections , Burkholderia cepacia complex/isolation & purification , Cystic Fibrosis , Pseudomonas Infections , Pseudomonas aeruginosa/isolation & purification , Respiratory Tract Infections , Staphylococcal Infections , Staphylococcus aureus/isolation & purification , Adolescent , Adult , Anti-Bacterial Agents/therapeutic use , Australia/epidemiology , Burkholderia Infections/diagnosis , Burkholderia Infections/drug therapy , Burkholderia Infections/epidemiology , Cystic Fibrosis/drug therapy , Cystic Fibrosis/epidemiology , Cystic Fibrosis/microbiology , Female , Humans , Longitudinal Studies , Male , Prevalence , Pseudomonas Infections/diagnosis , Pseudomonas Infections/drug therapy , Pseudomonas Infections/epidemiology , Respiratory Function Tests/methods , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/microbiology , Sputum/microbiology , Staphylococcal Infections/diagnosis , Staphylococcal Infections/drug therapy , Staphylococcal Infections/epidemiology , Transition to Adult Care/statistics & numerical data
13.
J Clin Diagn Res ; 10(5): ZC138-42, 2016 May.
Article in English | MEDLINE | ID: mdl-27437349

ABSTRACT

INTRODUCTION: The morphological characteristics and dimensions of external ear vary in different human ethnic races which can be utilized in forensics for personal identification of living or deceased. AIM: To determine uniqueness of morphological and biometric variations of both ears for individualization among North East (NE) and North West (NW) subpopulation of India. MATERIALS AND METHODS: The study was conducted on randomly selected 80 students, 40 from each subgroup. Nine ear parameters were recorded twice using digital Vernier's caliper by single investigator and two indices (Ear Index and Lobule Index) were calculated for both the ears. Morphological ear shapes and lobule attachment were also noted. Pearson's coefficient correlation test was performed on cross-tabulations to evaluate significant relationship between different variables. RESULTS: Of the total 35% free and 65% attached ear lobes were noted in both population groups. Oval ear shape was most commonly noted followed by triangular, rectangular and round in both populations. On comparing anthropometric measurements of ears in two populations it was found that except the tragus length and lobule index all other values were noted more in NW population. No statistical difference was found in ear and lobular indices of males and females although the left ear index and lobule index were found to be higher than right in both populations except in NW females where right lobule index was recorded more than left. CONCLUSION: The results obtained can be used in anthropological and forensic sciences for the inclusion and exclusion of persons for identification on the basis of ear variations.

14.
PLoS One ; 11(7): e0158327, 2016.
Article in English | MEDLINE | ID: mdl-27438997

ABSTRACT

Multiple sclerosis is an autoimmune disease of the central nervous system. Genome wide association studies have identified over 100 common variants associated with multiple sclerosis, the majority of which implicate immunologically relevant genes, particularly those involved in T-cell development. SNP rs13204742 at the THEMIS/PTPRK locus is one such variant. Here, we have demonstrated mutually exclusive use of exon 1 and 2 amongst 16 novel THEMIS isoforms. We also show inverse correlation between THEMIS expression in human CD4+ T-cells and dosage of the multiple sclerosis risk allele at rs13204742, driven by reduced expression of exon 1- containing isoforms. In silico analysis suggests that this may be due to cell-specific, allele-dependent binding of the transcription factors FoxP3 and/or E47. Research exploring the functional implications of GWAS variants is important for gaining an understanding of disease pathogenesis, with the ultimate aim of identifying new therapeutic targets.


Subject(s)
Genetic Predisposition to Disease , Intracellular Signaling Peptides and Proteins/genetics , Multiple Sclerosis/genetics , Quantitative Trait Loci/genetics , Adult , Alleles , CD4-Positive T-Lymphocytes/metabolism , Exons/genetics , Female , Gene Expression Regulation , Genome-Wide Association Study , Genotype , Humans , Intracellular Signaling Peptides and Proteins/biosynthesis , Male , Middle Aged , Multiple Sclerosis/immunology , Multiple Sclerosis/pathology , Polymorphism, Single Nucleotide , Protein Isoforms/biosynthesis , Protein Isoforms/genetics
16.
Pharm Res ; 33(6): 1456-71, 2016 06.
Article in English | MEDLINE | ID: mdl-26951566

ABSTRACT

PURPOSE: The purpose of this study was to develop an amorphous solid dispersion (SD) of an extremely water-insoluble and very weakly basic drug, itraconazole (ITZ), by interaction with weak organic acids and then drying that would enhance dissolution rate of drug and physical stability of formulation. METHODS: Aqueous solubility of ITZ in concentrated solutions of weak organic acids, such as glutaric, tartaric, malic and citric acid, was determined. Solutions with high drug solubility were dried using vacuum oven and the resulting SDs having 2 to 20% drug load were characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The dissolution of SDs was initially studied in 250 mL of 0.1 N HCl (pH 1.1), and any undissolved solids were collected and analyzed by PXRD. The pH of the dissolution medium was then changed from 1.1 to 5.5, particle size of precipitates were measured, and drug concentrations in solution were determined by filtration through membrane filters of varying pore sizes. RESULTS: The aqueous solubility of ITZ was greatly enhanced in presence of weak acids. While the solubility of ITZ in water was ~4 ng/ mL, it increased to 25-40 mg per g of solution at 25°C and 200 mg per g of solution at 65°C at a high acid concentration leading to extremely high solubilization. PXRD of SDs indicated that ITZ was present in the amorphous form, wherein the acid formed a partially crystalline matrix. ATR-FTIR results showed possible weak interactions, such as hydrogen bonding, between drug and acid but there was no salt formation. SDs formed highly supersaturated solutions at pH 1.1 and had superior dissolution rate as compared to amorphous drug and physical mixtures of drug and acids. Following the change in pH from 1.1 to 5.5, ITZ precipitated as mostly nanoparticles, providing high surface area for relatively rapid redissolution. CONCLUSIONS: A method of highly solubilizing an extremely water-insoluble drug, ITZ, in aqueous media and converting it into an amorphous form in a physically stable SD was successfully investigated. The dissolution rate and the extent of supersaturation of the drug in dissolution media improved greatly, and any precipitate formed at high pH had very small particle size.


Subject(s)
Antifungal Agents/chemistry , Citric Acid/chemistry , Desiccation , Itraconazole/chemistry , Technology, Pharmaceutical/methods , Calorimetry, Differential Scanning , Crystallization , Crystallography, X-Ray , Dicarboxylic Acids/chemistry , Drug Compounding , Drug Stability , Glutarates/chemistry , Hydrochloric Acid/chemistry , Hydrogen-Ion Concentration , Kinetics , Malates/chemistry , Particle Size , Powder Diffraction , Solubility , Spectroscopy, Fourier Transform Infrared , Tartrates/chemistry
17.
Insect Biochem Mol Biol ; 70: 170-83, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26792242

ABSTRACT

Bark beetles (Coleoptera: Scolytinae) are pests of many forests around the world. The mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, is a significant pest of western North American pine forests. The MPB is able to overcome the defences of pine trees through pheromone-assisted aggregation that results in a mass attack of host trees. These pheromones, both male and female produced, are believed to be biosynthesized in the midgut and/or fat bodies of these insects. We used metabolite analysis, quantitative proteomics (iTRAQ) and transcriptomics (RNA-seq) to identify proteins and transcripts differentially expressed between sexes and between tissues when treated with juvenile hormone III. Juvenile hormone III induced frontalin biosynthesis in males and trans-verbenol biosynthesis in females, as well as affected the expression of many proteins and transcripts in sex- and tissue-specific ways. Based on these analyses, we identified candidate genes involved in the biosynthesis of frontalin, exo-brevicomin, and trans-verbenol pheromones.


Subject(s)
Coleoptera/metabolism , Fat Body/metabolism , Metabolome , Pheromones/biosynthesis , Proteome , Transcriptome , Animals , Coleoptera/genetics , Male
18.
J Clin Diagn Res ; 10(11): OD05-OD06, 2016 Nov.
Article in English | MEDLINE | ID: mdl-28050425

ABSTRACT

Endomyocardial Fibrosis (EMF) is a form of progressive restrictive cardiomyopathy of unclear aetiology prevalent in areas within 150 of equator including coastal areas of Kerala a few decades back. It inflicts young adults and carries a poor prognosis due to limited options for treatment. Fortunately, the incidence of cases is now declining due to improvement in health and hygiene standards. Here, we review the aetiology and pathogenesis of EMF and report a case of a young male from Mumbai (non-endemic area) presenting with progressively worsening breathlessness and signs of heart failure unresponsive to conventional medical treatment. To delineate the extent of the disease transthoracic echocardiography and cardiac Magnetic Resonance Imaging (MRI) was done which revealed infiltrative lesions in left ventricular apex with grade 2/3 mitral regurgitation. Due to progressive and severe nature of the disease the patient was managed conservatively. Through this report we would like to rekindle the interest of reader in a forgotten tropical disease which is considered rare in this geographical area but should not be missed as a cause heart failure considering its significant mortality.

19.
Acta Anaesthesiol Taiwan ; 53(4): 123-30, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26510669

ABSTRACT

OBJECTIVES: Dexmedetomidine, an α2 agonist, has been evaluated for its hypnotic, analgesic, and anxiolytic properties in the intraoperative period and critical care setting. However, data on the effect of dexmedetomidine on attenuation of pressor response to direct laryngoscopy and tracheal intubation are limited. We studied the effect of a single preinduction intravenous dose of dexmedetomidine of 0.5 µg/kg on hemodynamic responses to tracheal intubation, and dose requirements of anesthetics for induction and their adverse effects. METHODS: Eighty adult patients scheduled for elective surgery under general anesthesia requiring tracheal intubation were included. Patients were randomized into two groups: dexmedetomidine and placebo (n = 40 each). The study drug was administered intravenously over a period of 10 minutes prior to induction. Direct laryngoscopy and endotracheal intubation were performed. Hemodynamic parameters, the total dose of propofol, and adverse effects were recorded during induction and postintubation periods for 15 minutes. RESULTS: The maximum percentage increase in the heart rate after intubation was 19.6% less in the dexmedetomidine group than that in the placebo group (12.96% vs. 32.57%). The maximum percentage increases in systolic blood pressure, diastolic blood pressure, and mean blood pressure after intubation were significantly lower in the dexmedetomidine group than in the placebo group (12.38% vs. 45.63%, 19.36% vs. 60.36%, and 15.34% vs. 50.33%, respectively). There was a significant reduction of the mean total dose of propofol required for induction, 1.04 mg/kg in the dexmedetomidine group versus 2.01 mg/kg in the placebo group (p < 0.001). No serious side effects or adverse reactions were observed in either group. CONCLUSION: Administration of a single preinduction intravenous dose of dexmedetomidine of 0.5 µg/kg resulted in significant attenuation of the rise in the heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure, until 5 minutes postintubation. It significantly reduced the dose requirements of propofol for induction and caused minimal side effects.


Subject(s)
Dexmedetomidine/administration & dosage , Laryngoscopy , Blood Pressure/drug effects , Heart Rate/drug effects , Hemodynamics/drug effects , Humans , Intubation, Intratracheal , Prospective Studies
20.
Plant J ; 83(5): 783-93, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26119826

ABSTRACT

Grindelia robusta or gumweed, is a medicinal herb of the sunflower family that forms a diverse suite of diterpenoid natural products. Its major constituents, grindelic acid and related grindelane diterpenoids accumulate in a resinous exudate covering the plants' surfaces, most prominently the unopened composite flower. Recent studies demonstrated potential pharmaceutical applications for grindelic acid and its synthetic derivatives. Mining of the previously published transcriptome of G. robusta flower tissue identified two additional diterpene synthases (diTPSs). We report the in vitro and in vivo functional characterization of an ent-kaurene synthase of general metabolism (GrTPS4) and a class II diTPS (GrTPS2) of specialized metabolism that converts geranylgeranyl diphosphate (GGPP) into labda-7,13E-dienyl diphosphate as verified by nuclear magnetic resonance (NMR) analysis. Tissue-specific transcript abundance of GrTPS2 in leaves and flowers accompanied by the presence of an endocyclic 7,13 double bond in labda-7,13E-dienyl diphosphate suggest that GrTPS2 catalyzes the first committed reaction in the biosynthesis of grindelic acid and related grindelane metabolites. With the formation of labda-7,13E-dienyl diphosphate, GrTPS2 adds an additional function to the portfolio of monofunctional class II diTPSs, which catalytically most closely resembles the bifunctional labda-7,13E-dien-15-ol synthase of the lycopod Selaginella moellendorffii. Together with a recently identified functional diTPS pair of G. robusta producing manoyl oxide, GrTPS2 lays the biosynthetic foundation of the diverse array of labdane-related diterpenoids in the genus Grindelia. Knowledge of these natural diterpenoid metabolic pathways paves the way for developing biotechnology approaches toward producing grindelic acid and related bioproducts.


Subject(s)
Alkyl and Aryl Transferases/metabolism , Diterpenes, Kaurane/metabolism , Diterpenes/metabolism , Grindelia/genetics , Grindelia/metabolism , Intramolecular Lyases/metabolism , Plant Proteins/metabolism , Alkyl and Aryl Transferases/genetics , Diterpenes, Kaurane/genetics , Gene Expression Profiling , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Plant , Intramolecular Lyases/genetics , Molecular Sequence Data , Phylogeny , Plant Proteins/genetics , Plants, Genetically Modified , Nicotiana/genetics
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