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Stability study for dolutegravir bulk drug was performed and the degradation products formed were identified by chromatography (HPLC, LCMS) and spectroscopy (ESI-MS, FTIR, 1H and 13C NMR) techniques. Degradation of the drug in acidic and peroxide environment yielded one common major degradant f ((2,4-difluorophenyl) methanamine) with a mass peak at m/z = 182.44. In addition to this, five more minor degradation products (a, b, c, d and e) were formed. The structure interpretation showed that the drug degraded to its synthetic precursor and no extra structures were formed. Hence, it was suggested that drug dolutegravir should be kept away from acidic and oxygen rich conditions. [ABSTRACT FROM AUTHOR]

With the growing power demand, the need for innovative and novel methods to operate large interconnected power systems has increased. This reflects more complexity and therefore less secure than before. Hence, modern power systems are more prone to widespread failures. The device that has enhanced the safe and reliable operation of the network and has contributed to capacity augmentation is Flexible AC Transmission System (FACTS). But this is very expensive and must be suitably sized and located to maximize the overall benefit to the system. The paper aims at determining the optimal location and size of the Static Var Compensator (SVC) by optimizing the multi-objective function formulated by different factors that define the system security, namely, voltage deviation, system overload and real power losses. The multi-objective optimization function has been optimized using a Modified Bacterial Foraging Optimization Algorithm (MBFOA). The results are presented and analyzed for an IEEE-30 bus test system and compared with the popular Genetic Algorithm (GA). [ABSTRACT FROM AUTHOR]

Power system planners have come to rely on FACTS devices to overcome several operational limitations in terms of thermal stability, voltage stability, and other inherent limitations offered by the transmission lines. One important aspect that has always intrigued the power system planners and researches alike is in regard to the location and sizing of FACTS devices. This work aims to address this intriguing question by identifying the optimal location and size of the Static Var Compensator (SVC). The optimal location and size is proposed to be identified by optimizing the multi-objective function, formulated by different factors that define the system security, namely Voltage Deviation, System Overload, and Real Power Losses. The multi-objective optimization function has been optimized using a Modified Bacterial Foraging Optimization Algorithm (MBFOA). The results are presented and analysed for an IEEE 30 bus test system. [ABSTRACT FROM AUTHOR]

A simple and new colorimetric method was developed for the estimation of emtricitabine. The proposed colorimetric method is based on the diazotisation of amine group present in emtricitabine, followed by colour complex formation using β-naphthol reagent. Parameters affecting the reaction were studied and conditions were optimized. The absorption maximum for the colour complex was observed at 559 nm. Linearity was obtained in the concentration range of 100-500 μg/ml for emtricitabine colour complex. The developed method was optimised and validated. The method was successfully applied for the estimation of emtricitabine in bulk and in tablets. This is the first method reported for colorimetric estimation of emtricitabine. [ABSTRACT FROM AUTHOR]

The three dimensional quantitative structure activity relationships(3D-QSAR) of a series of previously synthesized 1-(1H-1,2,4-triazole-1-yl)-2-(2,4-difluorophenyl)-3-substituted-2-propanol analogs(TDFPP) as antifungal against candida albicans, were studied using kNN(K nearest neighbour) protocol. This was in order to explore the selectivity requirements for fungicidal activity against C. albicans among these congeners. Theoretical active conformers for these TDFPP were generated. The best kNN model(N=44, q2= 0.8650, r2= 0.86504) showed contribution of the steric and electrostatic fields. The models were also external validated using 6 compounds(test set) not included in the model generation process. The statistical parameters from model indicate that the data are well fitted and have predictive ability. Moreover, the resulting contours and isosurface maps provide useful guidance for designing highly active ligands. The model is not only able to predict the activity of new compounds but also explains the important region in the molecules in the quantitative manner. [ABSTRACT FROM AUTHOR]

Single-photon emission computerized tomography for myocardial perfusion imaging (MPI) is a non-invasive technique. MPI is performed by subjecting the patient to exercise or by using a pharmacological stress agent. Regadenoson is a selective A2A adenosine receptor agonist used when MPI with exercise is contraindicated. It binds to the A2A receptor and stimulates adenylate cyclase, resulting in increased cAMP, which phosphorylates protein kinase A thereby opening the ATP-dependant potassium channels leading to hyperpolarization in the coronary vascular smooth muscle. After a single bolus dose of regadenoson 400 μg, a peak plasma concentration (Cmax) of 13.6 ng/mL is attained in 1-4 min, with a terminal half-life of 2 h. It has a quick onset, short duration sufficient enough for hyperemic response, with comparable efficacy to adenosine, but with fewer side-effects. The adverse effects of this drug are dyspnea, headache, flushing, chest pain and atrioventricular block. Regadenoson is used for MPI in patients with co-morbid conditions like mild-to-moderate reactive airway disease, obstructive lung disease and renal impairment. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study has been to assess the efficacy of duloxetine, a selective inhibitor of serotonin and norepinephrine reuptake, in the treatment of stress urinary incontinence (SUI) in women. Materials and Methods: The study included 50 women aged above 18 years with a predominant symptom of stress urinary incontinence (SUI). The case definition included a predominant symptom of SUI with a weekly incontinence episode frequency (IEF) of seven or greater and a positive cough stress test. All the patients received duloxetine 20 mg twice daily for 12 weeks. The primary outcome variables included the IEF and improvement in quality of life. Paired Student's 't' test was used to analyze changes in IEF. Results: The improvement with duloxetine treatment was found in 40 out of 50 patients. Remaining 10 patients did not show any improvement with duloxetine and discontinued the treatment. In 40 patients, the mean baseline IEF was 12.5/week. At the end of three months treatment, IEF was six/week. This shows a statistically significant reduction in the IEF. Also, there was a good improvement in quality of life with 65% of patients in the "very much better" and "much better" categories according to PGI-I scale. In the remaining 10 patients, there was no significant improvement after one month of treatment and patients underwent surgery. Conclusions: The findings support duloxetine as a potential treatment for women with stress urinary incontinence. [ABSTRACT FROM AUTHOR]

Objectives: To study the effect of nebivolol 5 mg once daily versus (S)-atenolol 25 mg once daily in patients with essential hypertension. Materials and Methods: A prospective study was conducted at RLJH and Research Centre which included 30 patients in each group with essential hypertension. The sex, age, presenting illness, and family history of the patients were recorded. Investigations such as blood sugar, urine analysis, kidney function test, lipid profile, and ECG were performed before starting the treatment. Any adverse effects during the treatment were noted. Blood pressure and heart rate were recorded at baseline and during follow-up. One group received nebivolol 5 mg once daily and other group (S)atenolol 25 mg once daily. Patients were followed-up every 15 days for 3 months. Results: Nebivolol group had 18 males and 12 females with mean age 50.6 ± 9.5 years, (S)-atenolol had 16 males and 14 females with mean age 54.4 ± 9 years. Patients receiving nebivolol and (S)-atenolol showed a significant fall (P <∙0001) in systolic (SBP), diastolic blood pressure (DBP), and heart rate at the end of first, second, and third month when compared to baseline. The difference in fall in SBP and DBP was insignificant between the groups, but fall in heart rate was significant (P <∙0001). Adverse effects such as headache, dizziness, and fatigue were reported with both drugs. Conclusion: Reduction of blood pressure with nebivolol and (S)atenolol was similar, but fall in blood pressure from baseline was highly significant in both groups. [ABSTRACT FROM AUTHOR]

A new, simple, sensitive, and reliable method is presented for the rapid spectrophotometric determination of trace amounts of iron(III) using leuco Xylene cyanol FF. The method is based on the oxidation of leuco Xylene cyanol FF (LXCFF) to its blue form of xylene cyanol FF by iron(III) in sulfuric acid medium (pH 2.0–3.0), the absorbance of the formed dye is measured in an acetate buffer medium (pH2.8–4.4) at 615 nm. The method obeys Beer's law over a concentration range of 0.15–0.9 μg mL-1 iron, having a molar absorptivity of 5.6×104 L mol-1 cm-1 and a Sandell's sensitivity of 0.0001 μg cm-2. The optimum reaction conditions and other analytical parameters have been evaluated. The developed method has been successfully applied to the determination of iron in water, soil, industrial effluent, plant material, pharmaceutical preparations, synthetic mixtures, and aluminum alloys. [ABSTRACT FROM AUTHOR]

A new, simple, highly sensitive and rapid spectrophotometric method has been described for the determination of platinum(IV). The method is based on the oxidation of leuco xylene cyanol FF (LXCFF) to its blue form of xylene cyanol FF by platinum(IV) in sulfuric acid medium (pH 1.0–2.5), the formed dye shows an absorption maximum at 620 nm in acetate buffer medium (pH 3.0–4.5). The method obeys Beer's law over a concentration range of 0.3 to 2.6 µg mL–1 platinum, having molar absorptivity and Sandell's sensitivity of 5.1×104 L mol–1 cm–1 and 0.0038 µg cm–2, respectively. The optimum reaction conditions and other analytical parameters have been evaluated. The developed method has been successfully applied to the determination of platinum in pharmaceutical preparations, soil, natural water, plant material, platinum-containing catalyst, and synthetic alloy samples. [ABSTRACT FROM AUTHOR]

Objective: The present investigation aims to predict the pharmacokinetic aspects and assessing the anti-Alzheimer's activity using both molecular docking platform and ex vivo pharmacological studies on muscle contraction. Materials and Methods: 2-Methyl Anthraquinone (MAQ) and Quinizarine (QNZ) were isolated from Rubia cordifolia L., and evaluated for absorption, distribution, metabolism, excretion, and toxicity. Molecular docking was performed with the help of Mcule software on five drug targets acetylcholinesterase enzyme (AChE), cyclin-dependent kinase5 (CDK5), glycogen synthase kinase 3ß (GSK3ß), monoamine oxidase (MAO-B), and ß-secretase enzyme (BACE). The pharmacological activity was screened by recording the muscle contractions of chick ileum. Results: The selected compounds were following Lipinski rule of five and the in silico studies have shown that the compounds possess drug likeliness, appreciated absorption, distribution, admired bioavailability, acceptable toxicity profile, and ability to cross the blood-brain barrier. The multi-target screening of AChE, CDK5, MAOB, GSK3ß, and BACE for MAQ and QNZ showed greater binding energy of -9.9, -10, -10.5, -9.4, and 8.2 kcal/mol and -9.6, -9.1, -9.9, -8.9, and 7.8 kcal/mol, respectively. The ex vivo studies have shown to possess synergistic effect in increasing the muscle contractility response of MAQ and QNZ with acetylcholine. Conclusion: The in silico parameters have shown good pharmacokinetic profile of the isolated compounds. The binding energy and affinity of amino acids with ligands have similar behavior in the ex vivo studies. It is suggested that the isolated compounds have promising anti-Alzheimer's activity. Further studies are required to confirm the possibility of anti-Alzheimer's activity of the selected compounds. [ABSTRACT FROM AUTHOR]

Therapy related AML (t- AML) accounts for 10-20% of all cases of AML. Cytotoxic agents implicated are alkylating agents, topoisomerase II inhibitors and rarely anti metabolites and anti tubulin agents. A growing incidence of therapy related acute promyelocytic leukemia (t-APL) has been reported over the last few decades in malignant and non malignant conditions. To the best of our knowledge this is the first t-APL case report to be reported in NSGCT post etoposide based therapy. [ABSTRACT FROM AUTHOR]

A response by G. M. Bengalorkar and colleagues to a letter to the editor about their article "Fospropofol: Clinical Pharmacology," published in the 2011 issue is presented.

This article presents several cases of patients who were given tacrolimus ointment to treat their localized vilitigo. The patients received Psoralen Ultra-Violet A (PUVA) phototherapy, cancer chemotherapy, immunosuppressants and corticosteroids. A majority of the patients showed response to the treatment. They demonstrated an improvement in their vitiligo area scoring index (VASI) scores.

A novel stability indicating reverse phase liquid chromatographic method has been developed for the simultaneous estimation of Losartan Potassium, Ramipril and Hydrochlorothiazide in bulk and Pharmaceutical formulations by using reverse phase Kromasil 100-5 C18 column [250mm x 4.6mm].The mobile phase (Methanol: phosphate buffer-pH 4.0) in the ratio of 70:30% v/v was pumped at a flow rate of 0.8ml/min and the column effluents were monitored at 233nm using Variable Wavelength UV detector. Linearity was obtained in the concentration range of 100-500 µg/ml for Losartan Potassium, 10-50 µg/ml for Ramipril and 20-100µg/ml for Hydrochlorothiazide. The established method was statistically validated according to the ICH Q2B guidelines and the percentage relative standard deviation for precision, robustness and ruggedness was found to be less than 2% indicating high degree of precision and robustness. The percentage recovery for the accuracy was found to be 100.76%, 96% and 98% for Losartan Potassium, Ramipril, and Hydrochlorothiazide respectively which were within the specified limits of recovery. Assay for the marketed formulation proved that 100.76% of Losartan Potassium and 96% of Ramipril and 98.22% of Hydrochlorothiazide. The proposed analytical method was observed for various stress condition and it was proved that more stable even under acidic, alkaline, peroxide and thermal degradation conditions. Hence due to its simplicity, rapidity, precision, accuracy and stability the developed HPLC method can be applied for the estimation of Losartan Potassium, Ramipril and Hydrochlorothiazide in pure and marketed formulations by a modern analyst. [ABSTRACT FROM AUTHOR]

Introduction: Arthroscopic anterior cruciate ligament (ACL) reconstruction is a very commonly done procedure in recent times. There is a need for a long-term outcome study of ACL reconstruction with a comparison between different types of fixation techniques. The graft fixation methods vary from aperture fixation (interference screws) to suspensory fixation methods (endobutton). Failure of graft incorporation and the development of tunnel widening (TW) after ACL reconstruction have been frequently reported in the long term in present literature. TW especially complicates revision ACL surgery. This is a prospective non-randomized clinical study of arthroscopic ACL reconstruction comparing the functional results between aperture fixation and suspensory fixation., Materials and Methods: Two groups of 14 patients who underwent autogenous hamstring ACL reconstruction with a minimum of 2-year follow-up evaluation were included in the study. The first group underwent aperture fixation with bioabsorbable interference screw at tibial and femoral side. The second group underwent suspensory fixation with endobutton fixation on the femoral side and biointerference screw on the tibial side. Both group patients were examined clinically before surgery, and at 3 months, 6 months, 1 year, and at 2 years. They were compared for functional outcome with Tegner Lysholm knee score., Observation and Results: There was a significant improvement in functional outcome in both the groups for base and at 3 months, also for 3 months and 6 months but for 6 months-1 year. Group 2 is almost significant. This improvement in outcome in Group 2 is consistent from 1 year to 2 years., Conclusion: In our prospective study comparing the outcomes of functional outcomes of ACL reconstruction with aperture fixation versus suspensory fixation on the femur, which was evaluated using Tegner Lysholm knee score over a period of 2 years, suspensory fixation was found to be better. However, further studies involving a larger series of cases are required for a better evaluation of the outcome., Competing Interests: Conflict of Interest: Nil, (Copyright: © Indian Orthopaedic Research Group.)

Polyethylene terephthalate (PET) is one of the highly produced synthetic polymers worldwide and had acquired attention due to its impact resistance, high clarity, and light weight. PET has become the first choice in making disposable bottles, leading to massive scales of production resulting in very high utilization across various facets of our daily life. Unfortunately, PET accumulates as waste and is highly resistant to biodegradation, thus presenting a serious threat to the ecosystem. Degradation of PET by enzymatic hydrolysis is a promising strategy to depolymerize the PET into its monomers. In recent studies, a plastic-degrading enzyme known as PETase ( Is PETase) from the Ideonella sakaiensis has been identified to hydrolyze PET. The wild-type enzyme from Ideonella sp., has been engineered to improve the catalytic activity. While the Is PETase and its variants have been the subject of extensive structural and biochemical studies, the corresponding computational studies to support the improved activity of the mutant enzyme is not fully understood. In this work, we employed all-atom classical molecular dynamics simulations of the wild-type and double mutant Is PETase enzymes to investigate the underlying reason for the improved catalytic activity in the double mutant by means of structure-dynamics-function relationship. Our results show that the engineered mutations reshape the active site structure, volume, and dynamics of the protein loops which is crucial for substrate binding. We also demonstrate that addition of aromatic and hydrogen bond-forming residues near catalytic site improves binding affinity. This work will enable the rational design of mutants for enhanced PET degrading activity.Communicated by Ramaswamy H. Sarma.

Leptospirosis is an emerging public health problem affecting people mainly from tropical and subtropical regions. Therefore, there is a need for rapid and sensitive tests for proper and prompt treatment. Recently we have demonstrated Carbo-Lip probe, which was fabricated through immuno recognition method with fluorescent dye functionalized LipL32 monoclonal antibodies, secondary antibody and Leptospira for rapid and accurate diagnosis. In an effort to validate Carbo-Lip, we collected clinical samples from a cohort of 104, consisting of 26 positive, 40 negative and 38 unconfirmed cases of Leptospirosis. Subsequently, the test was also compared and validated with the gold standard method microscopic agglutination test (MAT), IgM ELISA, IgM spot test, and culture. Carbo-Lip exhibited a sensitivity of 75% with specificity of 92.3% for Leptospirosis in comparison with MAT. The fabricated Carbo-Lip sensor could be used as a potential diagnostic tool for early detection of Leptospirosis in patients from endemic areas., (Copyright © 2022. Published by Elsevier B.V.)

Background: Tuberculosis is one of the leading causes of deaths due to infectious disease worldwide. There is an urgent need for developing new drugs due to the rising incidents of drug resistance. Previously, triazole molecules showing antitubercular activity, were reported. Various computational tools pave the way for a rational approach to understanding the structural importance of these compounds in inhibiting the growth of Mycobacterium Tuberculosis., Objective: The aim of this study is to develop and compare two different QSAR models based on a set of previously reported triazole molecules and use the best one for gaining structural insights into those molecules., Methods: In this current study, two separate models were made with CoMFA and CoMSIA descriptors based on a dataset of triazole molecules showing antitubercular activity. Several one dimensional (1D) descriptors were added to each of the models and the validation results and contour data generated from them were compared. The best model was analysed to give a detailed understanding of the triazole molecules and their role in the antitubercular activity., Results: The r 2 , q 2 , predicted r 2 and SEP (Standard error of prediction) for the CoMFA model were 0.866, 0.573, 0.119 and 0.736 respectively and for the CoMSIA model, the r 2 , q 2 , predicted r 2 and SEP were calculated to be 0.998, 0.634, 0.013 and 0.869 respectively. Although both the QSAR models produced acceptable internal and external validation scores, but the CoMSIA results were significantly better. The CoMSIA contours also provided a better match than CoMFA with most of the features of the active compound 30b. Hence, the CoMSIA model was chosen and its contours were explored for gaining structural insights into the triazole molecules., Conclusion: The CoMSIA contours helped us understand the role of several atoms and groups of the triazole molecules in their biological activity. The possibilities for substitution in the triazole compounds that would enhance the activity were also analyzed. Thus, this study paves the way for designing new antitubercular drugs in future., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Competing Interests: There are no conflicts of interest.

The global problem of acute poisoning has steadily increased over the past few years. It is an important cause of morbidity and mortality in developing countries. Better preventive and management strategies can be developed if the incidence and pattern of acute poisoning is known. The study aims at analyzing the pattern, cause and mortality rate of poisoning. The study was conducted in a rural area in South India. This retrospective study was conducted from January 2003-December 2003. The data was analysed using descriptive statistics. Out of the 225 cases 139 were males and 86 females. Poisoning was common in the age group of 21-30 years which was 84 cases and 11-20 years was 73 cases. The poisons consumed were as follows: Organophosphorous 135 cases, aluminum and zinc phosphide 50 cases, phenobarbitone 18 cases, benzodiazepines 7 cases, paracetamol 2 cases, miscellaneous 13 cases. 94% were suicides and 6% accidental. Mortality rate was 12.8%. Establishment of strict policies against the sale and availability of pesticides and over the counter drugs is an effective way to control organophosphorous and drug poisoning., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A simple and sensitized spectrophotometric method for the determination of trace amounts of beryllium has been described. The method is based on the formation of a ternary complex by the reaction of beryllium with haematoxylin in the presence of micellar medium (cationic surfactant, cetyltrimethylammonium bromide). The ternary complex of beryllium has a maximum absorbance at 592 nm and showed an excellent sensitivity (molar absorption coefficient of 7.07 x 10(4)L mol(-1)cm(-1) and the Sandell's sensitivity being 1.27 x 10(-4) microg cm(-2)) and reproducibility (within-day precision: R.S.D.

A highly sensitive and selective spectrophotometric method was developed for the determination of trace amounts of chromium with leuco Xylene cynaol FF. The method is based on the oxidation of leuco Xylene cyanol FF (LXCFF) to its blue form of Xylene cyanol FF by chromium(VI) in sulphuric acid medium (pH 1.2-2.4), the absorbance of the formed dye is measured in an acetate buffer medium (pH 3.0-4.6) at 615 nm. The method obeys Beer's law in the concentration range of 0.05-0.45 mug ml(-l) chromium, having molar absorptivity and Sandell's sensitivity of 8.23x10(4) l mol(-1) cm(-l) and 0.00063 mug cm(-2), respectively. All the variables were studied in order to optimise the reaction conditions. The developed method has been successfully applied to the determination of chromium in steels, pharmaceutical samples, industrial effluents, natural water, and soil.

A simple, rapid, and sensitive spectrophotometric method has been developed for the determination of selenium in real samples of water, soil, plant materials, human hair, and synthetic cosmetic and in pharmaceutical preparations. The method is based on the reaction of selenium with potassium iodide in an acidic medium to liberate iodine. The liberated iodine bleaches the violet color of thionin, and which is measured at 600 nm. This decrease in absorbance is directly proportional to selenium concentration and obeys Beer's law in the range 1-5 micro g selenium in a final volume of 10 mL (0.1-0.5 microg mL(-1)). The molar absorptivity and Sandell's sensitivity of the method were found to be 7.33 x 10(4) L mol(-1) cm(-1) and 0.0011 microg cm(-2), respectively. The optimum reaction conditions and other analytical conditions were evaluated. The effect of interfering ions on the determination is described.

A rapid and sensitive spectrophotometric method is described for the determination of trace amounts of selenium using Variamine Blue (VB) as a chromogenic reagent. The proposed method is based on the reaction of selenium with potassium iodide in an acidic medium to liberate iodine, which oxidizes Variamine Blue to form a violet-colored species having an absorption maximum at 546 nm. Beer's law is obeyed in the range 2-20 g of selenium in a final volume of 10 ml. The molar absorptivity and Sandell's sensitivity were found to be 2.6 x 10(4) l mol-1 cm-1 and 0.003 microgram cm-2, respectively. The optimum reaction conditions and other analytical parameters were evaluated. The effect of interfering ions on the determination is described. The proposed method has been successfully applied to the determination of selenium in real samples of water, soil, plant materials, human hair, and synthetic samples of cosmetics and pharmaceutical preparations.

It was recently reported that inducible nitric oxide synthase was expressed in advanced atheromatous plaques. So we investigated the effect of NO or peroxynitrite reactive product of NO or O(2)(-) released by iNOS induced in macrophages or T lymphocytes on inflammatory cells in atheromatous plaques of human coronary arteries by immunohistochemistry. We found that iNOS was expressed in T lymphocytes and macrophages in T lymphocytes and macrophages coexisted advanced atheromatous areas. Most of the smooth muscle cells are not coexisted with T lymphocytes. We could not find iNOS in those smooth muscle cells. Only a small number of iNOS-positive smooth muscle cells were found close to T lymphocytes and macrophages. Markers for apoptotic cells induced in situ terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) showed that many apoptotic T lymphocytes and macrophages existed near iNOS induced cells. Fas and Fas ligand were expressed in almost same areas that iNOS was expressed. By double-label immunostaining, Fas was expressed in T lymphocytes but Fas ligand was expressed in macrophages and in some T lymphocytes. These results suggest that NO from iNOS induces Fas and Fas ligand-mediated apoptosis and associates with regression of atherosclerosis. On the other hand, nitrotyrosine was detected wider areas than iNOS. So peroxynitrite from iNOS damages cells and tissues widely and may associate with progression of atherosclerosis. These results suggest an important role of iNOS in mediating both regressive changes and progressive change in atheromatous plaques., (Copyright 2000 Academic Press.)

While endothelial nitric oxide synthase is expressed in the endothelial cells of normal and atherosclerotic vessels, there are few reports about inducible nitric oxide synthase (iNOS) in atheroma. We investigated the expression of iNOS and its relation to inflammatory cells in atheroma. New Zealand White rabbits received a 1% cholesterol diet for 9 weeks (atherogenic diet) or a 1% cholesterol diet for 9 weeks then a normal diet for 36 weeks (reversible diet). The aortas were examined by immunohistochemical staining for anti-iNOS antibody, as well as antibodies for macrophages, T lymphocytes, and muscle actin. No iNOS was detected in normal aortas, intimal thickening, or fatty streaks. Although iNOS was detected in advanced plaques, it was not seen in smooth muscle-derived cells or endothelial cells, but was found in some macrophage-derived cells and in T lymphocytes. In regressive atherosclerotic aortas, iNOS was detected only in advanced plaques and not in macrophage-derived cells, but in T lymphocytes. These findings suggest that T lymphocytes and some macrophages induce iNOS through cytokine production in atheroma.