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1.
J Phys Chem B ; 128(28): 6816-6829, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-38959082

ABSTRACT

The effects of two ionic liquids (ILs), 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) and 1-butyl-1-methyl pyrrolidinium tetrafluoroborate ([bmp]BF4), on a mixture of phospholipids (PLs) 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), and 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol (DPPG) (6:3:1, M/M/M, 70% PL) in combination with 30 mol % cholesterol (CHOL) were investigated in the form of a solvent-spread monolayer and bilayer (vesicle). Surface pressure (π)-area (A) isotherm studies, using a Langmuir surface balance, revealed the formation of an expanded monolayer, while the cationic moiety of the IL molecules could electrostatically and hydrophobically bind to the PLs on the palisade layer. Turbidity, dynamic light scattering (size, ζ-potential, and polydispersity index), electron microscopy, small-angle X-ray/neutron scattering, fluorescence spectroscopy, and differential scanning calorimetric studies were carried out to evaluate the effects of IL on the structural organization of bilayer in the vesicles. The ILs could induce vesicle aggregation by acting as a "glue" at lower concentrations (<1.5 mM), while at higher concentrations, the ILs disrupt the bilayer structure. Besides, ILs could result in the thinning of the bilayer, evidenced from the scattering studies. Steady-state fluorescence anisotropy and lifetime studies suggest asymmetric insertion of ILs into the lipid bilayer. MTT assay using human blood lymphocytes indicates the safe application of vesicles in the presence of ILs, with a minimal toxicity of up to 2.5 mM IL in the dispersion. These results are proposed to have applications in the field of drug delivery systems with benign environmental impact.


Subject(s)
Ionic Liquids , Ionic Liquids/chemistry , Imidazoles/chemistry , Phospholipids/chemistry , Cholesterol/chemistry , Lipid Bilayers/chemistry , Surface Properties , 1,2-Dipalmitoylphosphatidylcholine/chemistry
2.
Planta ; 259(2): 37, 2024 Jan 13.
Article in English | MEDLINE | ID: mdl-38217720

ABSTRACT

MAIN CONCLUSION: The study provides nutritional profiling of unexploited little millets from Eastern Ghats, which has ample opportunities for future breeding programs for enhancing the food quality and holds great potential in food industry. Little millet is an important small millet native to the Indian subcontinent and their nutritional value has been underutilized compared to other cereals. It's nutritional and nutraceutical profiling is essential to integrate the plants in developmental interventions. The present study evaluated comprehensive nutritional, nutraceutical and physico-functional properties of 14 selected little millet genotypes originated from Eastern Ghats of India and compared them with an improved variety (OLM 208) of the locality. The proximate compositions (per 100 g) showed significant variations, with moisture content ranging from 4.13 to 8.48 g, ash from 1.90 to 5.15 g, fat from 2.35 to 5.74 g, protein from 10.46 to 13.83 g, carbohydrate from 70.92 to 77.89 g, fiber from 2.03 to 7.82 g and energy from 372.8 to 391.1 kcal. These little millet flours are rich in phenol 5.37-12.73 mg/g, flavonoid 1.06-8.25 µg/g, vitamin C 12.72-22.86 µg/g, antioxidants 7.22-23.17%, iron 20.38 to 61.60 mg/ kg and zinc 17.47 to 37.59 mg/ kg. The first two components of principal component analysis captures 73.0% of the total variation, which reflected huge variability among the investigated genotypes. Maximum heritability and genetic advance were recorded in flavonoid, fiber, iron, zinc, phenol and vitamin C across the populations. Taken together, some indigenous little millet genotypes such as Mami, Kalia and Bada, were exceptionally rich in fiber, protein, energy, flavonoid, vitamin C and antioxidants and are nutritionally superior compared to other varieties from the locality. These nutrition rich little millet genotypes have ample opportunities for future breeding programs to enhance the cereal quality and holds great potential in food industry for making high value functional foods.


Subject(s)
Panicum , Plant Breeding , Dietary Supplements , Antioxidants , Vitamins , Edible Grain/genetics , Iron , Phenols , Flavonoids , Ascorbic Acid , Zinc
3.
Cureus ; 14(4): e24402, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35481239

ABSTRACT

The most common cause of postoperative fever is infection. Other causes include cancer, iatrogenic causes, venous thromboembolism, secondary to prosthetic implants, and pyrexia of unknown origin. Here, we describe five cases of opioid-induced pyrexia. In all cases, an injection of morphine was given for postoperative analgesia and all those patients developed fever. All the possible causes of fever were excluded and then opioid was substituted with non-steroidal anti-inflammatory agents. Fever subsided in all the cases. Cessation of the offending drug led to the resolution of the fever in all five cases, and the patient required subsequent supportive care. However, adjunctive pharmacotherapy may also be needed in some patients.

4.
ACS Omega ; 5(31): 19315-19330, 2020 Aug 11.
Article in English | MEDLINE | ID: mdl-32803025

ABSTRACT

The authors report on the effect of manganese (Mn) substitution on the crystal chemistry, morphology, particle size distribution characteristics, chemical bonding, structure, and magnetic properties of cobalt ferrite (CoFe2O4) nanoparticles (NPs) synthesized by a simple, cost-effective, and eco-friendly one-pot aqueous hydrothermal method. Crystal structure analyses indicate that the Mn(II)-substituted cobalt ferrites, Co1-x Mn x Fe2O4 (CMFO, x = 0.0-0.5), were crystalline with a cubic inverse spinel structure (space group Fd 3 m ). The average crystallite size increases from 8 to 14 nm with increasing Mn(II) content; the crystal growth follows an exponential growth function while the lattice parameters follow Vegard's law. Chemical bonding analyses made using Raman spectroscopic studies further confirm the cubic inverse spinel phase. The relative changes in specific vibrational modes related to octahedral sites as a function of Mn content suggest a gradual change of measure of inversion of the ferrite lattice at nanoscale dimensions. Small-angle X-ray scattering and electron microscopy revealed a narrow particle size distribution with the spherical shape morphology of the CMFO NPs. The zero-field-cooled and field-cooled magnetic measurements revealed the superparamagnetic behavior of CMFO NPs at room temperature. The sample with x = 0.3 indicates a lower value of blocking temperature (9.16 K) with the improved (maximum) value of saturation magnetization. The results and the structure-composition-property correlation suggest that the economic, eco-friendly hydrothermal approach can be adopted to process superparamagnetic nanostructured magnetic materials at a relatively lower temperature for practical electronic and electromagnetic device applications.

5.
Acta Trop ; 156: 122-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26780552

ABSTRACT

From May to June 2014, an outbreak of dengue virus (DENV) illness occurred in the Havelock Island, South Andaman. Entomological investigations were undertaken during the peak of the outbreak, from 26th May-4th June, to identify the primary vector(s) involved in the transmission so that appropriate public health measures could be implemented. Adult mosquitoes were collected by BG-Sentinel traps in houses and neighborhoods of clinically ill patients. Water holding containers were inspected for the presence of mosquito larvae and pupae. Adult mosquitoes were analyzed by RT-PCR for the presence of nucleic acids of DENV and CHIKV. A total of 498 mosquitoes were collected and processed in 27 pools. The species composition comprised of 58.3% Aedes albopictus, 7.5% Aedes aegypti and 4.2% Aedes edwardsi and 3.1% constituted others. Two A. albopictus pools were found to be positive for DENV RNA. Sequencing of the RT PCR 511 base pair amplicon positive samples showed homology with DENV-3, suggesting that serotype-3 was responsible for the outbreak and A. albopictus was the primary vector responsible. This was supported by high container (10.1%), premise (25.4%) and Breteau (27.9) indices, with miscellaneous receptacles (2.4%), tree holes (1.2%) and discarded tires (1.2%) registering relatively higher container indices. This is the first report of detection of DENV in A. albopictus from Andaman and Nicobar Islands.


Subject(s)
Aedes/virology , Dengue Virus/isolation & purification , Dengue/transmission , Disease Outbreaks , Insect Vectors/virology , Aedes/classification , Animals , Female , Humans , India/epidemiology , Insect Vectors/classification , Islands , Male , Phylogeny , Serogroup
7.
ACS Nano ; 8(3): 2077-86, 2014 Mar 25.
Article in English | MEDLINE | ID: mdl-24494773

ABSTRACT

FeSe has been an interesting member of the Fe-based superconductor family ever since the discovery of superconductivity in this simple binary chalcogenide. Simplicity of composition and ease of synthesis has made FeSe, in particular, very lucrative as a test system to understand the unconventional nature of superconductivity, especially in low-dimensional models. In this article we report the synthesis of composite nanoparticles containing FeSe nanoislands entrapped within an ent-FeSe-Pd16Se15-Au nanoparticle and sharing an interface with Pd17Se15. This assembly exhibits a significant enhancement in the superconducting Tc (onset at 33 K) accompanied by a noticeable lattice compression of FeSe along the <001> and <101> directions. The Tc in FeSe is very sensitive to application of pressure and it has been shown that with increasing external pressure Tc can be increased almost 4-fold. In these composite nanoparticles reported here, immobilization of FeSe on the Pd17Se15 surface contributes to increasing the effect of interfacial pressure, thereby enhancing the Tc. The effect of interfacial pressure is also manifested in the contraction of the FeSe lattice (up to 3.8% in <001> direction) as observed through extensive high-resolution TEM imaging. The confined FeSe in these nanoparticles occupied a region of approximately 15-25 nm, where lattice compression was uniform over the entire FeSe region, thereby maximizing its effect in enhancing the Tc. The nanoparticles have been synthesized by a simple catalyst-aided vapor transport reaction at 800 °C where iron acetylacetonate and Se were used as precursors. Morphology and composition of these nanoparticles have been studied in details through extensive electron microscopy.

8.
Chin J Nat Med ; 11(5): 466-71, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24359768

ABSTRACT

INTRODUCTION: Cystone is an approved Ayurvedic polyherbal proprietary medicine used in India for various urinary disorders, including urolithiasis. AIM: To evaluate the protective effect of Cystone against hyperoxaluria-induced oxidative stress and calcium oxalate crystal deposition in urolithiasis. METHODS: Ethylene glycol (EG) (0.75%, V/V) in drinking water was given to rats for 28 days to induce urolithiasis with simultaneous treatment of Cystone (500 and 750 mg/kg body weight), and various urinary risk factors of urolithiasis and antioxidant markers were assessed. RESULTS: EG treatment lead to increased urine volume and lowered urinary pH, along with increased urinary excretion of oxalate, calcium and phosphate in untreated animals. These changes caused extensive calcium oxalate crystal deposition, increased lipid peroxidation and decreased activity of antioxidant enzymes (SOD, catalase and GPx) in the kidney of untreated rats. Cystone prevented these hyperoxaluric manifestations and inhibited calcium oxalate crystal deposition in treated rats at both doses. CONCLUSIONS: Cystone therapy provides protection against hyperoxaluria-induced oxidative stress and calcium oxalate crystal deposition by improving renal tissue antioxidant status and diuresis.


Subject(s)
Calcium Oxalate/metabolism , Hyperoxaluria/drug therapy , Oxidative Stress/drug effects , Plant Extracts/administration & dosage , Plants, Medicinal/chemistry , Urolithiasis/drug therapy , Animals , Calcium Oxalate/chemistry , Chemistry, Pharmaceutical , Humans , Hyperoxaluria/metabolism , India , Kidney/drug effects , Kidney/metabolism , Lipid Peroxidation/drug effects , Male , Rats , Rats, Wistar , Urolithiasis/metabolism
9.
Biomacromolecules ; 14(11): 4108-15, 2013 Nov 11.
Article in English | MEDLINE | ID: mdl-24164501

ABSTRACT

Dendrimer chemistries have virtually exploded in recent years with increasing interest in this class of polymers as gene delivery vehicles. An effective nucleic acid delivery vehicle must efficiently bind its cargo and form physically stable complexes. Most importantly, the nucleic acid must be protected in biological fluids and tissues, as RNA is extremely susceptible to nuclease degradation. Here, we characterized the association of nucleic acids with generation 4 PEGylated poly(amidoamine) dendrimer (mPEG-PAMAM-G4). We investigated the formation, size, and stability over time of the nanoplexes at various N/P ratios by gel shift and dynamic light scatter spectroscopy (DLS). Further characterization of the mPEG-PAMAM-G4/nucleic acid association was provided by atomic force microscopy (AFM) and by circular dichroism (CD). Importantly, mPEG-PAMAM-G4 complexation protected RNA from treatment with RNase A, degradation in serum, and various tissue homogenates. mPEG-PAMAM-G4 complexation also significantly enhanced the functional delivery of RNA in a novel engineered human melanoma cell line with splice-switching oligonucleotides (SSOs) targeting a recombinant luciferase transcript. mPEG-PAMAM-G4 triconjugates formed between gold nanoparticle (GNP) and particularly manganese oxide (MnO) nanorods, poly IC, an anticancer RNA, showed enhanced cancer-killing activity by an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell viability assay.


Subject(s)
Alternative Splicing/genetics , Dendrimers/chemistry , Nylons/chemistry , Oligonucleotides/genetics , Poly I-C/metabolism , Polyethylene Glycols/chemistry , Ribonuclease, Pancreatic/metabolism , Animals , Antineoplastic Agents/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Circular Dichroism , Dendrimers/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacology , Female , Humans , Melanoma/genetics , Melanoma/pathology , Mice , Microscopy, Atomic Force , Molecular Structure , Nanostructures/chemistry , Nylons/pharmacology , Oligonucleotides/metabolism , Poly I-C/genetics , Polyethylene Glycols/pharmacology , RNA/genetics , RNA/metabolism , RNA Stability/drug effects
10.
J Indian Assoc Pediatr Surg ; 18(1): 16-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23599577

ABSTRACT

AIM: Review of the clinical presentation, types (histology), and stages of presentation and overall outcome of ovarian tumors. MATERIALS AND METHODS: This is a retrospective study. Forty nine girls from 3 days to 12 years were included in the study. RESULTS: Fourteen girls had benign and thirty three had malignant ovarian tumors. One girl had bilateral ovarian non-Hodgkin lymphoma. Dysgerminoma (40%) was the commonest malignant tumor followed by malignant teratoma (16.6%). CONCLUSION: Pain and abdominal lump are the most common modes of presentation. Prognosis depends on the size of the tumor, stage and histology of the tumor. Conservative surgery should be the aim. Multidisciplinary management gives good prognosis.

11.
Electrochim Acta ; 97: 99-104, 2013 May 01.
Article in English | MEDLINE | ID: mdl-25684785

ABSTRACT

We describe the synthesis of zinc oxide (ZnO) nanoparticles and demonstrate their attachment to multiwalled carbon tubes, resulting in a composite with a unique synergistic effect. Morphology and size of ZnO nanostructures were controlled using hydrothermal synthesis, varying the hydrothermal treatment temperature, prior to attachment to carboxylic acid functionalized multi-walled carbon nanotubes for sensing applications. A strong dependence of electrocatalytic activity on nanosized ZnO shape was shown. High activity for H2O2 reduction was achieved when nanocomposite precursors with a roughly semi-spherical morphology (no needle-like particles present) formed at 90 °C. A 2.4-fold increase in cyclic voltammetry current accompanied by decrease in overpotential from the composites made from the nanosized, needle-like-free ZnO shapes was observed as compared to those composites produced from needle-like shaped ZnO. Electrocatalytic activity varied with pH, maximizing at pH 7.4. A stable, linear response for H2O2 concentrations was observed in the 1-20 mM concentration range.

12.
Article in English | WPRIM (Western Pacific) | ID: wpr-812636

ABSTRACT

INTRODUCTION@#Cystone is an approved Ayurvedic polyherbal proprietary medicine used in India for various urinary disorders, including urolithiasis.@*AIM@#To evaluate the protective effect of Cystone against hyperoxaluria-induced oxidative stress and calcium oxalate crystal deposition in urolithiasis.@*METHODS@#Ethylene glycol (EG) (0.75%, V/V) in drinking water was given to rats for 28 days to induce urolithiasis with simultaneous treatment of Cystone (500 and 750 mg/kg body weight), and various urinary risk factors of urolithiasis and antioxidant markers were assessed.@*RESULTS@#EG treatment lead to increased urine volume and lowered urinary pH, along with increased urinary excretion of oxalate, calcium and phosphate in untreated animals. These changes caused extensive calcium oxalate crystal deposition, increased lipid peroxidation and decreased activity of antioxidant enzymes (SOD, catalase and GPx) in the kidney of untreated rats. Cystone prevented these hyperoxaluric manifestations and inhibited calcium oxalate crystal deposition in treated rats at both doses.@*CONCLUSIONS@#Cystone therapy provides protection against hyperoxaluria-induced oxidative stress and calcium oxalate crystal deposition by improving renal tissue antioxidant status and diuresis.


Subject(s)
Animals , Humans , Male , Rats , Calcium Oxalate , Chemistry , Metabolism , Chemistry, Pharmaceutical , Hyperoxaluria , Drug Therapy , Metabolism , India , Kidney , Metabolism , Lipid Peroxidation , Oxidative Stress , Plant Extracts , Plants, Medicinal , Chemistry , Rats, Wistar , Urolithiasis , Drug Therapy , Metabolism
13.
J Indian Assoc Pediatr Surg ; 17(4): 176-7, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23243373

ABSTRACT

A rare case of unilateral scrotoschisis in a full term infant delivered by Caesarean section is reported.

14.
J Indian Assoc Pediatr Surg ; 17(1): 23-5, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22279360

ABSTRACT

Human tail is a curiosity, a cosmetic stigma and presents as an appendage in the lumbosacral region. Six patients of tail in the lumbosacral region are presented here to discuss the spectrum of presentation of human tails. The embryology, pathology and treatment of this entity are discussed along with a brief review of the literature.

15.
Pharm Biol ; 49(12): 1224-33, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21846174

ABSTRACT

INTRODUCTION: Boerhaavia diffusa Linn. (Nyctaginaceae) is widely used in traditional Indian medicines against renal afflictions including calcium oxalate (CaOx) urolithiasis and is known for antioxidant activity. OBJECTIVE: The present study was designed to investigate the ameliorating effect of aqueous extract of B. diffusa roots (BDE) in hyperoxaluric oxidative stress and renal cell injury. MATERIAL AND METHODS: In vitro antioxidant activity of BDE was estimated in terms of total phenolic content and 1,1-diphenyl-2-picryl hydrazyl free radical scavenging activity. Wistar albino rats were given 0.75% v/v ethylene glycol in drinking water to induce chronic hyperoxaluria and simultaneously BDE was given to nephrolithiasic treated rats at the dose of 100 and 200 mg/kg b.w. orally for 28 days. Urinary volume, oxalate, serum creatinine, blood urea nitrogen (BUN), malondialdehyde (MDA) and antioxidant enzyme (SOD, CAT, GST, GPx) were evaluated. RESULTS AND DISCUSSION: BDE extract was found to posses a high total phenolic content and exhibited significant free radicals scavenging activity. Oxalate excretion significantly increased in hyperoxaluric animals as compared to control which was protected in BDE-treated animals. BDE treatment significantly reduced level of MDA and improved the activity of antioxidant enzymes followed by reduction in BUN and serum creatinine. In addition, BDE reduced the number of CaOx monohydrate crystals in the urine. Histological analysis depicted that BDE treatment inhibited deposition of CaOx crystal and renal cell damage. CONCLUSION: The present study reveals that antioxidant activity of BDE significantly protects against hyperoxaluric oxidative stress and renal cell injury in urolithiasis.


Subject(s)
Acute Kidney Injury/drug therapy , Hyperoxaluria/drug therapy , Nyctaginaceae/chemistry , Oxidative Stress/drug effects , Plant Extracts/therapeutic use , Acute Kidney Injury/chemically induced , Acute Kidney Injury/pathology , Animals , Antioxidants/metabolism , Biphenyl Compounds , Catalase/metabolism , Chromatography, Thin Layer , Ethylene Glycol , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Hyperoxaluria/chemically induced , Kidney/pathology , Kidney Function Tests , Male , Malondialdehyde/metabolism , Oxalic Acid/metabolism , Picrates , Plant Extracts/chemistry , Plant Roots/chemistry , Rats , Rats, Wistar , Superoxide Dismutase/metabolism , Water
16.
Chem Commun (Camb) ; 46(15): 2551-3, 2010 Apr 21.
Article in English | MEDLINE | ID: mdl-20461846

ABSTRACT

We present the surprising result that the combination of the monotopic benzoate ligand with lanthanide ions leads to a 3D network which also possesses the chiral srs-topology.

17.
Dalton Trans ; 39(20): 4740-3, 2010 May 28.
Article in English | MEDLINE | ID: mdl-21488268

ABSTRACT

Using glycerol (H3gly) as a primary ligand, the decanuclear aggregate [Mn(II)2Mn(III)2Dy6(µ3-OH)2(Hgly)4(H2gly)2-(PhCO2)16(H2O)2]·10CH3CN (1) has been synthesised; it has a structure built up from two Mn2Dy2 heterocubane units linked through a central Dy2(µ-benzoate)4 paddle-wheel dimer and shows slow relaxation of its magnetisation.

18.
Biomed Pharmacother ; 56 Suppl 2: 257s-265s, 2002.
Article in English | MEDLINE | ID: mdl-12653178

ABSTRACT

Autonomic functions, such as increased sympathetic and parasympathetic activity and the brain's suprachiasmatic nucleus, higher nervous centres, depression, hostility and aggression appear to be important determinants of heart rate variability (HRV), which is, itself, an important risk factor of myocardial infarction, arrhythmias, sudden death, heart failure and atherosclerosis. The circadian rhythm of these complications with an increased occurrence in the second quarter of the day may be due to autonomic dysfunction as well as to the presence of excitatory brain and heart tissues. While increased sympathetic activity is associated with increased levels of cortisol, catecholamines, serotonin, renin, aldosterone, angiotensin and free radicals; increased parasympathetic activity may be associated with greater levels of acetylecholine, dopamine, nitric oxide, endorphins, coenzyme Q10, antioxidants and other protective factors. Recent studies indicate that hyperglycemia, diabetes, hyperlipidemia, ambient pollution, insulin resistance and mental stress can increase the risk of low HRV. These risk factors, which are known to favour cardiovascular disease, seem to act by decreasing HRV. There is evidence that regular fasting may modulate HRV and other risk factors of heart attack. While exercise is known to decrease HRV, exercise training may not have any adverse effect on HRV. In a recent study among 202 patients with acute myocardial infarction (AMI), the incidence of onset of chest pain was highest in the second quarter of the day (41.0%), mainly between 4.0-8.0 AM, followed by the fourth quarter, usually after large meals (28.2%). Emotion was the second most common trigger (43.5%). Cold weather was a predisposing factor in 29.2% and hot temperature (> 40 degrees celsius) was common in 24.7% of the patients. Dietary n-3 fatty acids and coenzyme Q10 have been found to prevent the increased circadian occurrence of cardiac events in our randomized controlled trials, possibly by increasing HRV. We have also found that n-3 fatty acids plus CoQ can decrease TNF-alpha and IL-6 in AMI which are pro-inflammatory agents. There is evidence that dietary n-3 fatty acids canenhance hippocampal acetylecholine levels, which may be protective. Similarly, the stimulation of the vagus nerve may inhibit TNF synthesis in the liver and acetylecholine, the principal vagal neurotransmitter, significantly attenuates the release of pro-inflammatory cytokines TNF-alpha, interleukin 1,6 and 18, but not the anti-inflammatory cytokine IL-10 in experiments. Therefore, any agent which can enhance brain acetylecholine levels, may be used as a therapeutic agent in protecting the suprachiasmatic nucleus, higher nervous centres, vagal activity and sympathetic nerve activity which are known to regulate the body clock and HRV and the risk of SCD and heart attack.


Subject(s)
Brain/physiology , Heart/physiology , Myocardial Infarction/etiology , Myocardial Infarction/physiopathology , Brain/blood supply , Circadian Rhythm/physiology , Heart Rate/physiology , Humans , Myocardial Infarction/psychology , Risk Factors , Stress, Psychological/physiopathology , Stress, Psychological/psychology
19.
Biomed Pharmacother ; 55 Suppl 1: 115s-124s, 2001.
Article in English | MEDLINE | ID: mdl-11774858

ABSTRACT

Recent studies indicate that there is an interaction between biorhythms, the biological clock and triggers, which may be important in the pathogenesis of altered heart rate variability (HRV) and blood pressure variability (BPV). Circadian rhythms are under the influence of, and physiological variables are mediated by the activation of the adrenals, sympathetic/parasympathetic, hypothalamic and pituitary activity. Emotional stress, physical exertion, sleep deprivation and large fatty meals are major triggers of myocardial ischemia, angina, infarction, sudden cardiac death (SCD) and stroke. These events have been reported to exhibit a circadian variation with increased frequency in the second quarter of the day, which has also been observed in our studies on Indians. Recent studies indicate that altered HRV and BPV are also important in the pathogenesis and progression of heart failure, atheroma and thrombosis. Mediation via beta-blockers, oestrogens, n-3 fatty acids, vitamin E and coenzyme Q10 and fasting appears to have a beneficial influence whereas progestins, nifedipine, stress and exercise may have an adverse effect on HRV and BPV. We have reported that plasma levels of vitamin E and C are lower in the second quarter of the day than at other times, indicating their role in the pathogenesis of variability and cardiac events. Prospective studies also indicate that HRV and BPV are important and independent risk factors for cardiovascular events. However, no study has yet been conducted in patients with abnormal HRV and BPV in a randomized, placebo-controlled intervention trial to find out whether improvement in variability can cause a significant reduction in cardiovascular events. There is a need to study the role of n-3 fatty acids, coenzyme Q10, the effect of regular physical training, medication and ACE inhibitors in patients with abnormal HRV and BPV to demonstrate that improving variability can modulate cardiovascular events.


Subject(s)
Circadian Rhythm/physiology , Heart Rate/physiology , Nutritional Physiological Phenomena , Animals , Blood Pressure/physiology , Cardiovascular Diseases/mortality , Cardiovascular Diseases/physiopathology , Humans , Life Style
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