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1.
J Oral Maxillofac Pathol ; 27(4): 778, 2023.
Article in English | MEDLINE | ID: mdl-38304493

ABSTRACT

Background: Red ginseng is an herb with many medicinal properties and aids as a mouth rinse with fewer side effects than chlorhexidine. Aim: The study aimed to compare the efficacy of red ginseng herbal mouth rinses with those of chlorhexidine and saline in oral cancer patients. Materials and Methods: The present pilot study was a double-blinded randomized control trial with 45 histopathologically diagnosed oral squamous cell carcinoma patients divided into three groups: two intervention groups (herbal and chlorhexidine mouth rinse) and one control group (saline). Saliva samples for each patient were collected at baseline and after 14 days of using the mouth rinses. A microbiological examination of salivary samples was done by analysing total oral bacterial load along with specific counts for Porphyromonas gingivalis and Fusobacterium nucleatum at baseline and after the usage of mouth rinse. Statistical Analysis: The data normality was analysed using the Shapiro-Wilk test, and following the normal distribution of data, parametric tests were employed. Paired t-test and one-way analysis of variance, followed by post hoc Bonferroni test, were used for inter-group and intra-group differences. Result: There was a significant mean difference in total colony count, Fusobacterium nucleatum, and Porphyromonas gingivalis with oral hygiene index and gingival index improvement in the red ginseng herbal mouth rinse group when compared to the chlorhexidine and saline groups. Conclusion: In this study, red ginseng mouth rinse exhibited an increased antibacterial effect compared to chlorhexidine and saline. Hence, red ginseng mouth rinse can be used in oral cancer patients to maintain oral health, thereby improving the prognosis of these patients.

2.
Clin J Am Soc Nephrol ; 16(10): 1531-1538, 2021 10.
Article in English | MEDLINE | ID: mdl-34233922

ABSTRACT

BACKGROUND AND OBJECTIVES: Residual native kidney function confers health benefits in patients on dialysis. It can facilitate control of extracellular volume and inorganic ion concentrations. Residual kidney function can also limit the accumulation of uremic solutes. This study assessed whether lower plasma concentrations of uremic solutes were associated with residual kidney function in pediatric patients on peritoneal dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Samples were analyzed from 29 pediatric patients on peritoneal dialysis, including 13 without residual kidney function and ten with residual kidney function. Metabolomic analysis by untargeted mass spectrometry compared plasma solute levels in patients with and without residual kidney function. Dialytic and residual clearances of selected solutes were also measured by assays using chemical standards. RESULTS: Metabolomic analysis showed that plasma levels of 256 uremic solutes in patients with residual kidney function averaged 64% (interquartile range, 51%-81%) of the values in patients without residual kidney function who had similar total Kt/Vurea. The plasma levels were significantly lower for 59 of the 256 solutes in the patients with residual kidney function and significantly higher for none. Assays using chemical standards showed that residual kidney function provides a higher portion of the total clearance for nonurea solutes than it does for urea. CONCLUSIONS: Concentrations of many uremic solutes are lower in patients on peritoneal dialysis with residual kidney function than in those without residual kidney function receiving similar treatment as assessed by Kt/Vurea.


Subject(s)
Kidney Diseases/therapy , Kidney Function Tests , Kidney/physiopathology , Mass Spectrometry , Metabolome , Metabolomics , Peritoneal Dialysis , Uremia/therapy , Adolescent , Age Factors , Biomarkers/blood , Child , Child, Preschool , Female , Humans , Infant , Kidney Diseases/blood , Kidney Diseases/diagnosis , Kidney Diseases/physiopathology , Male , Peritoneal Dialysis/adverse effects , Predictive Value of Tests , Treatment Outcome , United States , Uremia/blood , Uremia/diagnosis , Uremia/physiopathology
3.
J Oral Maxillofac Pathol ; 25(3): 503-508, 2021.
Article in English | MEDLINE | ID: mdl-35281141

ABSTRACT

Herbal rinses possess different medicinal properties. Numerous studies have reported the usefulness of various herbal oral rinses. Few studies claimed that herbal rinses are superior to synthetic mouth rinses for certain purposes, but there appears to be a lack of sound scientific evidence to prove the efficacy of herbal rinses in controlling oral plaque in cancer patients. This review analyses the various clinical studies on herbal rinses and aims to find the safety and efficacy of red ginseng mouth rinses over other available mouth rinses in carcinoma patients. A thorough electronic search was conducted in various databases and 10 articles were included in the review based on the inclusion and exclusion criteria. The data extracted were tabulated and analyzed. The risk of bias table was drawn. Meta-analysis was not performed due to the heterogeneity of the included studies. Of the 10 clinical trials included in the review, three studies appeared to have low risk of bias. The mean follow-up period was 14 days, ranging from 7 to 21 days. The sample size in each study was reported to be between 10 and 50, except one study with 240 samples. Seven studies have reported a significant difference between the herbal mouth rinse group and the chlorhexidine group. Of all the herbal rinses, mouth rinses with ginger extracts show more efficacy over other herbal rinses and red ginseng appears to be a more safer herbal rinse. Based on the available evidence, herbal mouth rinses are comparable to synthetic mouth rinses in their anti-bacterial properties. The red ginseng with anti-bacterial, anti-inflammatory and anti-cancerous properties may be an alternative mouth rinse in cancer patients. However, further clinical trials with more samples are required for better evidence.

4.
Neuropharmacology ; 183: 108406, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33212113

ABSTRACT

Hemopressin (PVNFKFLSH in rats, and PVNFKLLSH in humans and mice), a fragment derived from the α-chain of hemoglobin, was the first peptide described to have type 1 cannabinoid receptor activity. While hemopressin was shown to have inverse agonist/antagonistic activity, extended forms of hemopressin (i.e. RVD-hemopressin, also called pepcan-12) exhibit type 1 and type 2 cannabinoid receptor agonistic/allosteric activity, and recent studies suggest that they can activate intracellular mitochondrial cannabinoid receptors. Therefore, hemopressin and hemopressin-related peptides could have location-specific and biased pharmacological action, which would increase the possibilities for fine-tunning and broadening cannabinoid receptor signal transduction. Consistent with this, hemopressins were shown to play a role in a number of physiological processes including antinociceptive and anti-inflammatory activity, regulation of food intake, learning and memory. The shortest active hemopressin fragment, NFKF, delays the first seizure induced by pilocarpine, and prevents neurodegeneration in an experimental model of autoimmune encephalomyelitis. These functions of hemopressins could be due to engagement of both cannabinoid and non-cannabinoid receptor systems. Self-assembled nanofibrils of hemopressin have pH-sensitive switchable surface-active properties, and show potential as inflammation and cancer targeted drug-delivery systems. Upon disruption of the self-assembled hemopressin nanofibril emulsion, the intrinsic analgesic and anti-inflammatory properties of hemopressin could help bolster the therapeutic effect of anti-inflammatory or anti-cancer formulations. In this article, we briefly review the molecular and behavioral pharmacological properties of hemopressins, and summarize studies on the intricate and unique mode of generation and binding of these peptides to cannabinoid receptors. Thus, the review provides a window into the current status of hemopressins in expanding the repertoire of signaling and activity by the endocannabinoid system, in addition to their new potential for pharmaceutic formulations.


Subject(s)
Cannabinoid Receptor Agonists/pharmacology , Endocannabinoids/physiology , Hemoglobins/pharmacology , Peptide Fragments/pharmacology , Animals , Hemoglobins/chemistry , Hemoglobins/genetics , Hemoglobins/physiology , Humans , Mice , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/physiology , Rats , Receptors, Cannabinoid
5.
Neuropharmacology, v. 183, 108406, fev. 2021
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3346

ABSTRACT

Hemopressin (PVNFKFLSH in rats, and PVNFKLLSH in humans and mice), a fragment derived from the α-chain of hemoglobin, was the first peptide described to have type 1 cannabinoid receptor activity. While hemopressin was shown to have inverse agonist/antagonistic activity, extended forms of hemopressin (i.e. RVD-hemopressin, also called pepcan-12) exhibit type 1 and type 2 cannabinoid receptor agonistic/allosteric activity, and recent studies suggest that they can activate intracellular mitochondrial cannabinoid receptors. Therefore, hemopressin and hemopressin-related peptides could have location-specific and biased pharmacological action, which would increase the possibilities for fine-tunning and broadening cannabinoid receptor signal transduction. Consistent with this, hemopressins were shown to play a role in a number of physiological processes including antinociceptive and anti-inflammatory activity, regulation of food intake, learning and memory. The shortest active hemopressin fragment, NFKF, delays the first seizure induced by pilocarpine, and prevents neurodegeneration in an experimental model of autoimmune encephalomyelitis. These functions of hemopressins could be due to engagement of both cannabinoid and non-cannabinoid receptor systems. Self-assembled nanofibrils of hemopressin have pH-sensitive switchable surface-active properties, and show potential as inflammation and cancer targeted drug-delivery systems. Upon disruption of the self-assembled hemopressin nanofibril emulsion, the intrinsic analgesic and anti-inflammatory properties of hemopressin could help bolster the therapeutic effect of anti-inflammatory or anti-cancer formulations. In this article, we briefly review the molecular and behavioral pharmacological properties of hemopressins, and summarize studies on the intricate and unique mode of generation and binding of these peptides to cannabinoid receptors. Thus, the review provides a window into the current status of hemopressins in expanding the repertoire of signaling and activity by the endocannabinoid system, in addition to their new potential for pharmaceutic formulations.

6.
Pediatr Nephrol ; 35(2): 305-312, 2020 02.
Article in English | MEDLINE | ID: mdl-31728748

ABSTRACT

BACKGROUND: Dialysis in children as well as adults is prescribed to achieve a target spKt/Vurea, where Vurea is the volume of distribution of urea. Waste solute production may however be more closely correlated with body surface area (BSA) than Vurea which rises in proportion with body weight. Plasma levels of waste solutes may thus be higher in smaller patients when targeting spKt/Vurea since they have higher BSA relative to body weight. This study measured levels of pseudouridine (PU), a novel marker solute whose production is closely proportional to BSA, to test whether prescription of dialysis to a target spKt/Vurea results in higher plasma levels of PU in smaller children. METHODS: PU and urea nitrogen (ureaN) were measured in plasma and dialysate at the midweek hemodialysis session in 20 pediatric patients, with BSA ranging from 0.65-1.87m2. Mathematical modeling was employed to estimate solute production rates and average plasma solute levels. RESULTS: The dialytic clearance (Kd) of PU was proportional to that of ureaN (average KdPU/KdUreaN 0.69 ± 0.13, r2 0.84, p < 0.001). Production of PU rose in proportion with BSA (r2 0.57, p < 0.001). The pretreatment plasma level of PU was significantly higher in smaller children (r2 0.20, p = 0.051) while the pretreatment level of ureaN did not vary with size. CONCLUSIONS: Prescribing dialysis based on urea kinetics may leave uremic solutes at higher levels in small children. Measurement of a solute produced proportional to BSA may provide a better index of dialysis adequacy than measurement of urea.


Subject(s)
Biomarkers/blood , Body Size , Models, Theoretical , Pseudouridine/blood , Renal Dialysis/methods , Adolescent , Body Surface Area , Child , Child, Preschool , Female , Humans , Male , Renal Dialysis/standards , Urea/blood , Young Adult
7.
J Forensic Dent Sci ; 11(3): 163-166, 2019.
Article in English | MEDLINE | ID: mdl-32801590

ABSTRACT

AIM: The aim of this study is to evaluate the efficacy of cheiloscopy (the study of lip prints) and dermatoglyphics (the study of fingerprints) in screening diabetic patients. MATERIALS AND METHODS: The study sample comprised 100 individuals in the age group of 17-60 years, of which fifty were diabetics and fifty controls who reported to the Department of Oral Medicine, Thai Moogambigai Dental College and Hospital. Lip prints were collected and categorized based on the Suzuki and Tsuchihashi system. Fingerprint patterns were obtained and classified according to the Henry's system of classification. RESULTS: Type II and IV lip print patterns were predominant in diabetic patients and Type I lip print patterns in controls. The difference was statistically significant. There was no significant difference in fingerprint patterns between the study groups. Gender-wise analysis for lip print and fingerprint patterns did not yield significant results. CONCLUSION: Cheiloscopy is a potential screening tool for type 2 diabetes mellitus. Dermatoglyphics cannot be used as a screening tool in type 2 diabetes mellitus.

8.
J Oral Maxillofac Pathol ; 22(3): 332-334, 2018.
Article in English | MEDLINE | ID: mdl-30651676

ABSTRACT

AIM: The aim of the study was to compare the efficacy of an herbal mouthwash containing red ginseng extract with different brands of commercially available chemical mouthwashes. OBJECTIVE: The objective of the study was to evaluate the effectiveness of herbal mouthwash (Dr. Dental care liquid) in reducing the oral bacterial count and compare it with the efficacy of commercially available mouthwashes such as Rexidine, Listerine and Colgate Plax. MATERIALS AND METHODS: The study includes sixty normal individuals (aged 18-24 years) who were divided into four groups of 15 individuals each. The participants of each group were given four different mouthwashes (Dr. Dental Care liquid, Colgate Plax, Listerine and Rexidine) and asked to use it twice daily for 5 days. Saliva samples were collected before the use of mouthwash and also after 5 days of using the mouthwashes. Culture and microscopic examination of salivary samples was done, and oral bacterial load present in the saliva samples was counted before and after the mouth rinse use. RESULTS: The results were compared using Wilcoxon sign-rank test. Among the four mouthwashes, the herbal mouthwash, Dr. Dental care liquid exhibited maximum efficacy in reducing the amount of bacteria followed by Colgate Plax, Listerine and Rexidine. CONCLUSION: The herbal mouthwash, Dr. Dental care liquid, contains red ginseng extract, a herb with immense medicinal values. In this study, the herbal mouth rinse exhibited increased antibacterial action compared with other commercially available chemical mouth rinses. Hence, we conclude that the ginseng-containing herbal mouthwash can be considered as a safe and effective oral hygiene aid.

9.
Ther Adv Psychopharmacol ; 5(3): 172-8, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26199720

ABSTRACT

Persons with schizophrenia are at a high risk, almost 4.6 times more likely, of having drug abuse problems than persons without psychiatric illness. Among the influential proposals to explain such a high comorbidity rate, the 'self-medication hypothesis' proposed that persons with schizophrenia take to drugs in an effort to cope with the illness and medication side effects. In support of the self-medication hypothesis, data from our earlier clinical study confirmed the strong association between neuroleptic dysphoria and negative subjective responses and comorbid drug abuse. Though dopamine has been consistently suspected as one of the major culprits for the development of neuroleptic dysphoria, it is only recently our neuroimaging studies correlated the emergence of neuroleptic dysphoria to the low level of striatal dopamine functioning. Similarly, more evidence has recently emerged linking low striatal dopamine with the development of vulnerability for drug addictive states in schizophrenia. The convergence of evidence from both the dysphoria and comorbidity research, implicating the role of low striatal dopamine in both conditions, has led us to propose that the person with schizophrenia who develops dysphoria and comorbid addictive disorder is likely to be one and the same.

10.
J Biomed Nanotechnol ; 10(6): 970-81, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24749392

ABSTRACT

The scaffolds for bone tissue engineering should be porous to harbor the growth of new tissue ingrowths, biodegradable with no toxic end products, and biocompatible with no cytotoxicity. In this study we report that Diopside (CaMgSi2O6) (Dp) particles can be synthesized at a more economical route using the agricultural waste rice straw. Along with chitosan (CS) matrix, the CS/Dp scaffolds were synthesized and evaluated for their physico-chemical properties by SEM, EDS, XRD, FT-IR studies. Addition of Dp particles to chitosan matrix decreased water retention capacity but there was no change in their degradation properties. Dp particles in CS/Dp scaffolds exhibited good affinity for protein adsorption. Apatite forming ability of the CS/Dp scaffolds depicted their bioactivity. These scaffolds were found to be compatible with human osteoblastic cells (MG-63) and the cells were able to attach and proliferate with extended morphology on the CS/Dp membranes. The CS/Dp scaffolds supported up regulation of mRNA expression of osteoblast differentiation marker genes such alkaline phosphatase (ALP), type I collagen (COL-I) in the presence of osteogenic environment suggesting their osteo-conductive nature. In vivo rat model system identified that the CS/Dp scaffolds are biocompatible and may have the property of recruiting cells due to deposition of collagen. Hence, these studies suggest that the prepared CS/Dp scaffolds have potential applications towards bone tissue engineering.


Subject(s)
Bone Substitutes/chemical synthesis , Chitosan/chemistry , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Silicic Acid/chemistry , Tissue Engineering/instrumentation , Tissue Scaffolds , Animals , Chitosan/adverse effects , Elastic Modulus , Equipment Design , Equipment Failure Analysis , Male , Materials Testing , Nanoparticles/adverse effects , Particle Size , Rats , Rats, Wistar , Silicic Acid/adverse effects , Tensile Strength
11.
J Phys Condens Matter ; 23(8): 086006, 2011 Mar 02.
Article in English | MEDLINE | ID: mdl-21411909

ABSTRACT

We examine the magneto-transport, static and dynamic magnetic responses of the single phase glassy insulating compound La(0.67)Ca(0.33)Mn(1-x)Zn(x)O(3) (x = 0.10). This compound undergoes a field induced metal-insulator transition and exhibits colossal magnetoresistance for H ≥ 2 T. Many experimental features, such as a frequency dependent cusp in the in-phase component of linear ac susceptibility at a temperature T'(f), a broad maximum (at T(a)) in the ZFC cooled thermo-magnetization close to T'(f), large thermo-magnetic irreversibility below T(a), non-saturation of magnetization at 5 K even under 12 T with a characteristic S shape in the virgin curve, monotonic increase of the coercivity at low fields under ZFC condition as one approaches the T'(f), logarithmic relaxation of thermo-magnetization and ageing effects below T(a) and a characteristic maximum in the magnetic viscosity below the spin-glass transition temperature (T(g)) indicate a spin-glass-like state at low temperatures. This is further substantiated by the absence of second order non-linear ac susceptibility, a characteristic negative maximum at T(g) in third order non-linear ac susceptibility (χ'(3)), the critical divergence of χ'(3) as a function of temperature and ac probe field and an unusually large linear term in the low temperature specific heat.

12.
Eye (Lond) ; 21(8): 1102-8, 2007 Aug.
Article in English | MEDLINE | ID: mdl-16858437

ABSTRACT

AIMS: To evaluate the epidemiology, microbiological features, as well as antibiotic susceptibility patterns of Nocardiafrom cases with ocular nocardial infections seen over a period of 8 years in a tertiary eye care hospital. METHODS: Microbiology records of 164 cases of culture-proven ocular nocardial infection diagnosed between March 1997 and February 2005 were reviewed retrospectively. The outcome data included isolation rate, predisposing factors, demography (age and sex), and category of infection, utility of conventional diagnostic methods, microbiological profile, and antibiogram-resistogram patterns. RESULTS: A total of 164 (3.1%) Nocardiaspecies were identified among 5378 culture-proven cases. Ninety-six (58.5%) isolates were from corneal scrapings followed by vitreous biopsy (17.0%). Most (58.0%) of the cases were between 51 and 80 age groups. Male preponderance was obvious. All the 164 (100%) nocardial infections were identified by culture. Of 125 ocular specimens subjected to Gram's staining, nocaridal filaments were identified in 70 (56%) specimens. In addition to KOH mounting, modified AFB staining was also found to be helpful. Upon in vitrosusceptibility testing, 98.7 and 90.2% of nocardial isolates showed sensitivity towards amikacin and ciprofloxacin, respectively. CONCLUSIONS: Ocular nocardiosis is relatively rare among ocular infections. Amikacin and ciprofloxacin are highly effective in treating ocular nocardiasis. Prompt and accurate microbiological diagnosis and early administration of these antibiotics may have a positive effect on the ocular outcome as well as in controlling nocardial prevalence.


Subject(s)
Cornea/microbiology , Eye Infections, Bacterial/drug therapy , Nocardia Infections/drug therapy , Adolescent , Adult , Aged , Aged, 80 and over , Amikacin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Child , Child, Preschool , Ciprofloxacin/therapeutic use , Cornea/anatomy & histology , Eye Infections, Bacterial/epidemiology , Female , Humans , India/epidemiology , Infant , Infant, Newborn , Male , Microbial Sensitivity Tests , Middle Aged , Nocardia Infections/epidemiology , Nocardia Infections/microbiology , Treatment Outcome
13.
Infect Immun ; 74(10): 5763-72, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16988254

ABSTRACT

In this study, we demonstrated that the methyltransferase activity associated with Dam was essential for attenuation of Aeromonas hydrophila virulence. We mutated aspartic acid and tyrosine residues to alanine within the conserved DPPY catalytic motif of Dam and transformed the pBAD/damD/A, pBAD/damY/A, and pBAD/damAhSSU (with the native dam gene) recombinant plasmids into the Escherichia coli GM33 (dam-deficient) strain. Genomic DNA (gDNA) isolated from either of the E. coli GM33 strains harboring the pBAD vector with the mutated dam gene was resistant to DpnI digestion and sensitive to DpnII restriction endonuclease cutting. These findings were contrary to those with the gDNA of E. coli GM33 strain containing the pBAD/damAhSSU plasmid, indicating nonmethylation of E. coli gDNA with mutated Dam. Overproduction of mutated Dam in A. hydrophila resulted in bacterial motility, hemolytic and cytotoxic activities associated with the cytotoxic enterotoxin (Act), and protease activity similar to that of the wild-type (WT) bacterium, which harbored the pBAD vector and served as a control strain. On the contrary, overproduction of native Dam resulted in decreased bacterial motility, increased Act-associated biological effects, and increased protease activity. Lactone production, an indicator of quorum sensing, was increased when the native dam gene was overexpressed, with its levels returning to that of the control strain when the dam gene was mutated. These effects of Dam appeared to be mediated through a regulatory glucose-inhibited division A protein. Infection of mice with the mutated Dam-overproducing strains resulted in mortality rates similar to those for the control strain, with 100% of the animals dying within 2 to 3 days with two 50% lethal doses (LD50s) of the WT bacterium. Importantly, immunization of mice with a native-Dam-overproducing strain at the same LD50 did not result in any lethality and provided protection to animals after subsequent challenge with a lethal dose of the control strain.


Subject(s)
Aeromonas hydrophila/enzymology , Aeromonas hydrophila/pathogenicity , Bacterial Proteins/metabolism , Site-Specific DNA-Methyltransferase (Adenine-Specific)/metabolism , Transcriptional Activation , Aeromonas hydrophila/immunology , Amino Acid Sequence/genetics , Animals , Bacterial Proteins/genetics , Catalytic Domain/genetics , DNA Methylation , Enterotoxins/metabolism , Genetic Vectors/genetics , Gram-Negative Bacterial Infections/prevention & control , Lactones/metabolism , Mice , Phenotype , Plasmids/genetics , Site-Specific DNA-Methyltransferase (Adenine-Specific)/genetics , Virulence/genetics
14.
J Phys Condens Matter ; 18(17): 4427-42, 2006 May 03.
Article in English | MEDLINE | ID: mdl-21690793

ABSTRACT

In this paper, we examine the possible influence of extrinsic factors on the electrical and magnetotransport of La(0.67)Ca(0.33)Mn(1-x)Ru(x)O(3) (x≤0.10). Ru substitution results in double metal-insulator transitions (MITs) at T(MI1) and T(MI2), both exhibiting magnetoresistance (MR). No additional magnetic signal corresponding to a second low-temperature maximum (LTM) at T(MI2) could be observed, either in ac susceptibility (χ(')) or in specific heat (C(p)). Typical grain sizes of ∼18 000-20 000 nm, as estimated from the scanning electron microscope (SEM) micrographs, are not so small as to warrant an LTM. The absence of additional peaks in the high statistics powder x-ray diffraction (XRD), a linear systematic increase of the unit cell parameters, close matching of the transition temperatures in resistivity, χ(') and C(p) and their linear systematic decrease with x, and an homogeneous distribution of Mn, Ru and O at arbitrarily selected regions within and across the grains exclude chemical inhomogeneity in the samples. The insensitivity of grain boundary MR at 5 K to Ru composition indicates that the grain boundary is not altered to result in an LTM. Oxygen stoichiometry of all the compounds is close to the nominal value of 3. These results not only exclude the extrinsic factors, but also establish that double MITs, both exhibiting MR, are intrinsic to Ru substituted La(0.67)Ca(0.33)MnO(3).

15.
Indian J Med Res ; 109: 157-63, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10402764

ABSTRACT

Very little information is available on the changes in the erythrocyte membrane composition during storage of blood at 4 degrees C, particularly with respect to the glycosaminoglycans and glycoproteins. In view of this, a detailed study was carried out on the changes in the membrane proteins, glycosaminoglycans (GAG), carbohydrate components of glycoproteins, cholesterol, phospholipids and vitamin E in blood stored in glass bottles and a di-(2-ethyl hexyl) phthalate (DEHP) plasticized PVC bag (Penpol blood bag). Blood was collected in CPDA solution in glass bottles and in Penpol blood bags and kept at 4 +/- 1 degrees C. Analysis was made immediately after blood collection and after 28 and 42 days. Significant increase in the total protein in the erythrocyte membrane was observed during storage of whole blood in glass bottles and Penpol blood bag at 4 degrees C. This increase was progressively more with increase in storage time. Significant changes were also observed in GAG, carbohydrate components of glycoproteins, cholesterol, phospholipids and vitamin E in the erythrocyte membrane under these conditions. The protein:GAG ratio, protein:carbohydrate ratio, cholesterol:phospholipid ratio as well as protein:lipid ratio showed significant increase in the membrane. The extent of these changes was lower in the Penpol bag, indicating the stabilizing effect of DEHP on the erythrocyte membrane.


Subject(s)
Blood Preservation/instrumentation , Cryopreservation , Diethylhexyl Phthalate , Erythrocyte Membrane/metabolism , Plastics , Polyvinyl Chloride , Humans
16.
Vox Sang ; 76(4): 220-5, 1999.
Article in English | MEDLINE | ID: mdl-10394141

ABSTRACT

BACKGROUND AND OBJECTIVES: There is increase in lipid peroxidation with consequent increase in hemolysis when blood is stored in di-(2-ethyl hexyl)phthalate (DEHP) plasticized bags. Studies carried out by us and others have indicated the ability of red cells to synthesize NAD+ from added nicotinic acid. Apart from the role of NAD+ in glycolysis, NADPH is required for reduction of oxidized glutathione to its reduced form by glutathione reductase. Reduced glutathione is an important antioxidant, which protects cell membrane from oxidative damage. Reduced glutathione is also involved in the regeneration of vitamin E, another important membrane antioxidant. In view of these, a study was undertaken to find out the effect of addition of nicotinic acid to the citrate-phosphate-dextrose-adenine (CPDA) solution on lipid peroxidation and integrity of red cells when whole blood is stored in DEHP plasticized bags. MATERIALS AND METHODS: Blood was collected in Penpol blood storage bags (which is a DEHP plasticized bag) in CPDA solution in the presence and absence of nicotinic acid. Various parameters of lipid peroxidation and membrane stability - level of malondialdehyde (MDA), conjugated dienes, vitamin E, reduced glutathione, plasma Hb and K+, levels of adenosine triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) were studied in the blood samples after various periods. RESULTS: Plasma Hb and K+ concentrations were significantly lower in the presence of added nicotinic acid both after 28 and 42 days. Concentration of MDA and conjugated dienes was lower and the levels of reduced glutathione and vitamin E higher in the presence of nicotinic acid. ATP levels were not significantly different, but 2,3-DPG levels were higher. pH of the blood was nearer to 7.0 in the presence of nicotinic acid, while leaching out of DEHP into the blood was significantly lower. CONCLUSION: Inclusion of nicotinic acid in the CPDA solution has a beneficial effect in that (1) it reduces plasma Hb and K+; (2) reduces lipid peroxidation and increases antioxidant protection; (3) maintains pH nearer to 7.0, and (4) decreases the leaching out of DEHP into the blood.


Subject(s)
Blood Preservation , Hemolysis/drug effects , Lipid Peroxidation/drug effects , Niacin/pharmacology , 2,3-Diphosphoglycerate/blood , Adenine/pharmacology , Adenosine Triphosphate/blood , Citrates/pharmacology , Diethylhexyl Phthalate/blood , Diethylhexyl Phthalate/pharmacology , Erythrocyte Membrane/physiology , Erythrocytes/chemistry , Glucose/pharmacology , Hemoglobins/analysis , Humans , Hydrogen-Ion Concentration , Malondialdehyde/blood , Phosphates/pharmacology , Potassium/blood
17.
Vox Sang ; 75(3): 198-204, 1998.
Article in English | MEDLINE | ID: mdl-9852407

ABSTRACT

BACKGROUND AND OBJECTIVES: Previous work in this laboratory has shown significant decrease in vitamin E in erythrocytes in blood stored in polyvinyl chloride (PVC) bags plasticized with di-[2-ethyl hexyl] phthalate (DEHP), and in erythrocytes incubated in vitro with DEHP. Since vitamin E is a major antioxidant, a study was carried out to find out whether this decrease observed in vitamin E has an effect on lipid peroxidation in blood stored in DEHP-plasticized PVC blood bags. MATERIALS AND METHODS: Blood was collected in Penpol blood storage bags (which is a DEHP-plasticized PVC bag) and parameters of lipid peroxidation, i.e. activity of superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione reductase, concentration of malondialdehyde (MDA), conjugated dienes, hydroperoxides, glutathione and vitamin E studied in erythrocytes after various periods of storage as compared to glass bottles. Erythrocytes were also incubated in vitro with DEHP with and without vitamin E, and changes in lipid peroxidation studied. RESULTS: Blood stored in Penpol bags showed increased lipid peroxidation in erythrocytes as compared to that stored in glass bottles, as is evident from a greater increase in MDA and a greater decrease in glutathione and a significant decrease in vitamin E. The addition of vitamin E decreased the formation of MDA and conjugated dienes and prevented the decrease in vitamin E. However in spite of increased lipid peroxidation in the presence of DEHP, the release of K+ and hemoglobin from erythrocytes was lower. When there was an increase in DEHP taken up by erythrocytes, there was a corresponding decrease in vitamin E. More important, whenever there was an increase in vitamin E in erythrocytes (when RBCs in the presence of DEHP were incubated with vitamin E), there was a progressive decrease in DEHP. CONCLUSION: DEHP caused increased lipid peroxidation in erythrocytes. At the same time, it decreased the release of K+ and hemoglobin from erythrocytes. It is possible that the stabilizing effect of DEHP on the erythrocyte membrane may offset the detrimental effects of the increased lipid peroxidation it causes.


Subject(s)
Antioxidants/pharmacology , Blood Preservation/instrumentation , Diethylhexyl Phthalate/chemistry , Erythrocyte Membrane/chemistry , Lipid Peroxidation , Membrane Lipids/chemistry , Plasticizers/chemistry , Polyvinyl Chloride/chemistry , Vitamin E/pharmacology , Adult , Catalase/blood , Diethylhexyl Phthalate/pharmacology , Erythrocyte Membrane/drug effects , Glass , Glutathione Peroxidase/blood , Humans , Lipid Peroxidation/drug effects , Malondialdehyde/blood , Membrane Lipids/blood , Superoxide Dismutase/blood , Vitamin E/blood
18.
Indian J Biochem Biophys ; 35(4): 236-40, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9854904

ABSTRACT

Synthesis of NAD+ from nicotinic acid by erythrocytes incubated in SAGM phosphate solution and effect of di-[2-ethyl hexyl] phthalate, a plasticizer commonly used in PVC blood/component storage bags, on this synthesis was studied. Erythrocytes are able to synthesise NAD+ in SAGM (sodium chloride, adenine, glucose, mannitol) phosphate solution and this synthesis was more in the presence of added nicotinic acid (optimum concentration 1 mM). The level of NAD+ decreased when the incubation period was increased from 24 to 48 hr. Glutamine had a deleterious effect on this synthesis, possibly due to the decrease in pH. Di-[2-ethyl hexyl] phthalate had an inhibitory effect on NAD+ synthesis when the cells were incubated in SAGM phosphate solution, either alone or in the presence of added nicotinic acid. There was significant decrease in the release of potassium and haemoglobin from the cells in the presence of nicotinic acid, indicating increased red cell stability.


Subject(s)
Erythrocytes/metabolism , NAD/biosynthesis , Adenine , Adenosine Triphosphate/blood , Blood Preservation , Diethylhexyl Phthalate/pharmacology , Erythrocytes/drug effects , Glucose , Humans , In Vitro Techniques , Mannitol , NAD/blood , Niacin/metabolism , Niacin/pharmacology , Plasticizers/pharmacology , Sodium Chloride
19.
Vox Sang ; 75(2): 139-44, 1998.
Article in English | MEDLINE | ID: mdl-9784668

ABSTRACT

BACKGROUND AND OBJECTIVES: Significant amounts of di(2-ethylhexyl) phthlate (DEHP) leach into blood stored in DEHP-plasticized PVC bags. The aim of this study was to find out whether DEHP at these low levels has any effect on the concentration of vitamin E, an antioxidant which affords protection against free radical damage. MATERIALS AND METHODS: DEHP was administered in low doses (150-750 microg/100 g body weight) to rats intraperitoneally and the concentration of vitamin E in the liver and testes was measured. Concentration of vitamin E was also measured in blood stored in glass bottles in the presence and absence of DEHP and in blood stored in DEHP-plasticized PVC bags. RESULTS: A decrease in the concentration of vitamin E was observed in all cases. Administration of vitamin E to rats and incorporation of vitamin E in the additive solution in the case of blood prevented this decrease. CONCLUSION: DEHP even at very low doses caused a decrease in the concentration of vitamin E in liver and tests of rats given this substance. Blood stored in DEHP-plasticized bags also showed a decrease in the concentration of vitamin E.


Subject(s)
Diethylhexyl Phthalate/pharmacology , Plasticizers/pharmacology , Vitamin E/analysis , Animals , Blood Preservation/instrumentation , Diethylhexyl Phthalate/analysis , Diethylhexyl Phthalate/blood , Erythrocytes/chemistry , Humans , Liver/chemistry , Liver/drug effects , Male , Rats , Rats, Wistar , Testis/chemistry , Testis/drug effects , Vitamin E/blood
20.
Indian J Med Res ; 108: 17-23, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9745214

ABSTRACT

The effect of DEHP [di-(2-ethly hexyl) phthalate] on lipid peroxidation in the liver in rats and in primary cultures of rat hepatocytes incubated with it was studied. The doses of DEHP used in this study corresponded to the low levels of this substance leaching into blood stored in DEHP plasticised PVC bags. Increased activity of superoxide dismutase (SOD) and catalase, increased concentration of malondialdehyde (MDA) and conjugated dienes and decrease in the concentration of glutathione and vitamin E have been observed in the liver of rats administered DEHP. Primary cultures of rat hepatocytes incubated with DEHP also showed increase in the activity of these enzymes, increase in the concentration of MDA and decrease in vitamin E. These results indicate that DEHP promotes lipid peroxidation. Incorporation of vitamin E along with DEHP into the culture medium containing hepatocytes counteracted these effects.


Subject(s)
Diethylhexyl Phthalate/pharmacology , Lipid Peroxidation/drug effects , Liver/drug effects , Animals , Catalase/biosynthesis , Cells, Cultured , Liver/cytology , Liver/metabolism , Male , Rats , Rats, Wistar , Superoxide Dismutase/biosynthesis , Vitamin E/metabolism
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