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1.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38651988

ABSTRACT

The temporal evolution of the electron cloud at room temperature has been recorded through a resonance circuit by observing the axial oscillation frequency of its center of mass. The electron cloud undergoes radial expansion by interacting with the residual gas molecules, and it is finally lost upon hitting the Penning trap electrodes. It has been confirmed through detailed experimental investigations that the unique temporal pattern of frequency variation is a consequence of the cloud's radial expansion. Consequently, this approach offers a non-destructive means for single-shot detection, enabling continuous monitoring of the electron cloud's radial expansion during the confinement time. This technique offers a significant advantage over its destructive alternatives.

2.
Front Oncol ; 12: 859846, 2022.
Article in English | MEDLINE | ID: mdl-35865463

ABSTRACT

Background: Fluoropyrimidines (fluorouracil [5-FU], capecitabine) and irinotecan are commonly prescribed chemotherapy agents for gastrointestinal (GI) malignancies. Pharmacogenetic (PGx) testing for germline DPYD and UGT1A1 variants associated with reduced enzyme activity holds the potential to identify patients at high risk for severe chemotherapy-induced toxicity. Slow adoption of PGx testing in routine clinical care is due to implementation barriers, including long test turnaround times, lack of integration in the electronic health record (EHR), and ambiguity in test cost coverage. We sought to establish PGx testing in our health system following the Exploration, Preparation, Implementation, Sustainment (EPIS) framework as a guide. Our implementation study aims to address barriers to PGx testing. Methods: The Implementing Pharmacogenetic Testing in Gastrointestinal Cancers (IMPACT-GI) study is a non-randomized, pragmatic, open-label implementation study at three sites within a major academic health system. Eligible patients with a GI malignancy indicated for treatment with 5-FU, capecitabine, or irinotecan will undergo PGx testing prior to chemotherapy initiation. Specimens will be sent to an academic clinical laboratory followed by return of results in the EHR with appropriate clinical decision support for the care team. We hypothesize that the availability of a rapid turnaround PGx test with specific dosing recommendations will increase PGx test utilization to guide pharmacotherapy decisions and improve patient safety outcomes. Primary implementation endpoints are feasibility, fidelity, and penetrance. Exploratory analyses for clinical effectiveness of genotyping will include assessing grade ≥3 treatment-related toxicity using available clinical data, patient-reported outcomes, and quality of life measures. Conclusion: We describe the formative work conducted to prepare our health system for DPYD and UGT1A1 testing. Our prospective implementation study will evaluate the clinical implementation of this testing program and create the infrastructure necessary to ensure sustainability of PGx testing in our health system. The results of this study may help other institutions interested in implementing PGx testing in oncology care. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT04736472, identifier [NCT04736472].

3.
Rev Sci Instrum ; 93(1): 014706, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-35104962

ABSTRACT

A helical resonator serves as a key element for the detection of the trapped charged particles in a Penning trap. In order to compare the performance of the helical resonators, the concept of figure of merit (FOM) was introduced by Ulmer et al. [Nucl. Instrum. Methods Phys. Res., Sect. A 705, 55-60 (2013)]. In this work, we optimized the geometrical parameters of a resonator by numerical simulations keeping its outer dimensions and the diameter of the copper wire fixed and obtained the best possible value of FOM under these constraints. The corresponding 95 MHz helical resonator has been designed and fabricated, and its measured value of FOM is in good agreement with the simulated values. An empirical relationship between the total length of the wire to make the helical coil and the resonance frequency has been obtained. The simulations show that the FOM increases considerably with the increase in the conductivity of the building material, and this would be useful in detecting the feeble trap signal in cryogenic environment.

4.
BMC Cancer ; 22(1): 47, 2022 Jan 08.
Article in English | MEDLINE | ID: mdl-34996412

ABSTRACT

BACKGROUND: Pharmacogenetic (PGx) testing for germline variants in the DPYD and UGT1A1 genes can be used to guide fluoropyrimidine and irinotecan dosing, respectively. Despite the known association between PGx variants and chemotherapy toxicity, preemptive testing prior to chemotherapy initiation is rarely performed in routine practice. METHODS: We conducted a qualitative study of oncology clinicians to identify barriers to using preemptive PGx testing to guide chemotherapy dosing in patients with gastrointestinal malignancies. Each participant completed a semi-structured interview informed by the Consolidated Framework for Implementation Research (CFIR). Interviews were analyzed using an inductive content analysis approach. RESULTS: Participants included sixteen medical oncologists and nine oncology pharmacists from one academic medical center and two community hospitals in Pennsylvania. Barriers to the use of preemptive PGx testing to guide chemotherapy dosing mapped to four CFIR domains: intervention characteristics, outer setting, inner setting, and characteristics of individuals. The most prominent themes included 1) a limited evidence base, 2) a cumbersome and lengthy testing process, and 3) a lack of insurance coverage for preemptive PGx testing. Additional barriers included clinician lack of knowledge, difficulty remembering to order PGx testing for eligible patients, challenges with PGx test interpretation, a questionable impact of preemptive PGx testing on clinical care, and a lack of alternative therapeutic options for some patients found to have actionable PGx variants. CONCLUSIONS: Successful adoption of preemptive PGx-guided chemotherapy dosing in patients with gastrointestinal malignancies will require a multifaceted effort to demonstrate clinical effectiveness while addressing the contextual factors identified in this study.


Subject(s)
Antineoplastic Agents/administration & dosage , Clinical Decision-Making , Gastrointestinal Neoplasms/drug therapy , Pharmacogenomic Testing , Adult , Aged , Antineoplastic Agents/therapeutic use , Female , Health Services Accessibility , Humans , Male , Middle Aged , Oncologists/statistics & numerical data , Practice Patterns, Physicians' , Qualitative Research
5.
Rev Sci Instrum ; 91(7): 074707, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32752874

ABSTRACT

We have developed and tested a compact non-magnetic feedthrough made of epoxy resin and capable of maintaining vacuum leak tightness over a wide temperature range (300 K-4 K). It is equipped with 15 electrical pins and three 50 Ω coaxial lines. The feedthrough has been designed to apply a high voltage (up to 5 kV) and transmit radio-frequency signals for operating a Penning trap over a wide temperature range (300 K-4 K). The characteristic impedances of the coaxial lines have been measured at 300 K and 77 K and found to remain ∼50 Ω over the frequency range of our interest (10 MHz-80 MHz). The details of its fabrication and performance over a wide temperature range have been discussed.

6.
Cancer Chemother Pharmacol ; 80(6): 1141-1146, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29098381

ABSTRACT

PURPOSE: The potential inhibition of CYP3A4 by lapatinib was studied using midazolam as a probe substrate in patients with cancer. METHODS: This was a partially randomized, 4-period, 4-sequence, 4-treatment, cross-over study in 24 patients with advanced cancer. Single 1-mg IV and 3-mg oral doses of midazolam were given 2 days apart, in a partially random order, on study days 1, 3, 9, and 11. Lapatinib 1500-mg was administered orally once daily on study days 4 through 11. Midazolam plasma concentrations were measured up to 24-h post dosing, and lapatinib plasma concentrations measured prior to each midazolam dose. RESULTS: Lapatinib increased the geometric mean (95% CIs) midazolam AUC(o-∞) by 45% (31-60%) after the oral dose and by 14% (0-29%) after the IV dose, and prolonged the midazolam elimination half-life by 48% (22-81%) after the oral dose and by 20% (2-40%) after the IV dose. Lapatinib decreased midazolam total clearance by 13% (1-23%), while total bioavailability was increased 23% (4-46%) without changes in apparent volume of distribution or hepatic bioavailability. CONCLUSION: These data show that lapatinib caused weak inhibition of gastrointestinal CYP3A4 in vivo. This suggests that oral CYP3A4 drug substrates with a narrow therapeutic index may need dose reduction if lapatinib is to be co-prescribed.


Subject(s)
Antineoplastic Agents/therapeutic use , Cytochrome P-450 CYP3A/metabolism , Midazolam/therapeutic use , Neoplasms/drug therapy , Quinazolines/therapeutic use , Adult , Aged , Antineoplastic Agents/pharmacokinetics , Cross-Over Studies , Female , Humans , Lapatinib , Male , Midazolam/pharmacokinetics , Middle Aged , Quinazolines/pharmacokinetics
7.
Naunyn Schmiedebergs Arch Pharmacol ; 387(7): 659-65, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24722817

ABSTRACT

Sepsis is often associated with upregulation of nitric oxide production and fever, and it is common to control an excessive febrile response with antipyretic therapy and external cooling. Our aim was to evaluate the effect of hypothermia on NO production in a model of septic shock. Rats were anesthetized, ventilated, and instrumented for hemodynamic monitoring and divided into four groups. Normothermic controls (NC) received saline intravenously and were maintained at 37 °C. Hypothermic controls (HC) received saline but were allowed to become hypothermic. Normothermic endotoxic (NE) received Escherichia Coli lipopolysaccharides (LPS) intravenously to induce endotoxic shock and was maintained at 37 °C. Hypothermic endotoxic (HE) received LPS intravenously and was allowed to become hypothermic. Exhaled NO (NOe) was measured from mixed expired gas at time zero and every 30 min, for 5 h. After injection of LPS, NOe increased substantially in the NE group (700 ± 24 ppb), but increased only to 25 ± 2 ppb in the HE group. NOe increased to 90 ± 3 ppb in the NC group, and to 17.6 ± 3.1 ppb in the HC group after 5 h (P < 0.05), whilst blood pressure remained stable. In the HE group, blood pressure fell immediately after injection of the LPS, but thereafter remained stable despite the rise in NOe. In the NE group, the blood pressure fell gradually, and the animals became hypotensive. During the natural course of endotoxemia in anesthetized rats, allowing severe hypothermia to ensue by not actively managing temperature and hemodynamics resulted in significantly reduced expired NO concentrations, lung injury, and prolonged survival. The clinical benefits of such a finding currently remain unclear and merit further investigation.


Subject(s)
Endotoxemia/metabolism , Hypothermia/metabolism , Nitric Oxide/metabolism , Shock, Septic/metabolism , Anesthesia , Animals , Lung/metabolism , Male , Peroxidase/metabolism , Rats, Sprague-Dawley
9.
Clin Toxicol (Phila) ; 48(10): 967-73, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21192754

ABSTRACT

INTRODUCTION: Ethylene glycol, diethylene glycol and methanol are widely available chemicals and are found in a variety of common household products including antifreeze, windshield washer fluid, brake fluid and lubricants. Following ingestion of these glycols and methanol, patients frequently develop an early neurological syndrome consisting of inebriation, ataxia, and if severe, seizures and coma. Though uncommon, a neurological syndrome may also develop as a delayed complication. METHODS: Using Pub Med 438 references were identified of which 45 were relevant. FEATURES: Ethylene glycol poisoning has produced cranial nerve deficits (usually VII nerve dysfunction) after a delay of 5-20 days, Parkinsonism and cerebral edema. Diethylene glycol ingestion has been associated with the development of optic nerve injury, cranial nerve deficits, quadraparesis and peripheral neuropathy. Methanol poisoning has led to Parkinsonism and polyneuropathy. MECHANISMS OF TOXICITY: Oxalate crystal deposition likely causes the cranial neuropathies related to ethylene glycol and 2-hydroxyethoxyacetic acid is thought to be the causal moiety in cranial neuropathies resulting from diethylene glycol toxicity. Formic acid is implicated in the optic nerve damage associated with methanol. CONCLUSIONS: Uncommonly, delayed neurological syndromes may develop as complications of poisoning due to ethylene glycol, diethylene glycol and methanol; the onset of such neurological damage is often days or even weeks post-ingestion. Further research is required to explain why the facial nerve is the cranial nerve most commonly involved and why the basal ganglia are predisposed to injury.


Subject(s)
Ethylene Glycol/poisoning , Ethylene Glycols/poisoning , Methanol/poisoning , Animals , Ethylene Glycol/metabolism , Ethylene Glycols/metabolism , Humans , Methanol/metabolism
10.
Article in English | WHO IRIS | ID: who-170919

ABSTRACT

Dengue is a notifiable disease in the National Capital Territory of Delhi (NCT Delhi), India. All hospitals, both in the public and private sectors, are under obligation to report serologically confirmed cases of dengue to local health authorities. During the period 2005 to 2009, a total of 7402 serologically confirmed dengue cases were reported from the National Capital Territory of Delhi. Records of 5603 dengue cases (76%) admitted in hospitals were analysed for severity of disease. The trend of dengue has changed from cyclic to annual occurrence. DHF/DSS accounted for 518 (9.2%) of the admitted hospital cases in all age groups. The proportion of males found positive for dengue infection was 68% while females constituted 32%. The transmission season in NCT Delhi is the rainy season (July to October). Container indices monitored in six major hospitals remained persistently high in all the five years (range 1.5 to 23.9) and carried high potential for spatial spread of dengue infection to other parts of the NCT, Delhi region.


Subject(s)
Disaster Vulnerability , Hospitals , Aedes
11.
J Clin Oncol ; 27(31): 5262-9, 2009 Nov 01.
Article in English | MEDLINE | ID: mdl-19738123

ABSTRACT

PURPOSE: This phase I, first-in-human study evaluated the safety, tolerability, pharmacokinetics, and maximum-tolerated dose (MTD) of an oral platelet-derived growth factor receptor inhibitor, CP-868,596. PATIENTS AND METHODS: Patients with advanced solid tumors were eligible. Dose escalations were performed in three groups with two formulations: uncoated on an empty stomach (UES), uncoated with food (UFED), and film-coated (FC) without food. Initial dose escalation in the UES group was followed by parallel escalations in the UFED and FC groups. RESULTS: Fifty-nine patients enrolled. CP-868,596 was escalated from 100 mg to 340 mg daily in the UES group, from 60 mg to 100 mg twice daily in the UFED group, and from 100 mg once daily to 140 mg twice daily in the FC group. MTDs were 200 mg daily in the UES group and 100 mg twice daily in the FC group; MTD was not reached at 100 mg twice daily in the UFED group. Dose-limiting toxicities included hematuria, increased gamma-glutamyltransferase or ALT, insomnia, and nausea/vomiting. Most treatment-related AEs were of grades 1 to 2 severity; nausea, vomiting, and diarrhea were reported most frequently. Administration with food generally improved tolerability. CP-868,596 was absorbed slowly; systemic exposure parameters appeared to increase greater than proportionally with dose. Mean serum concentrations exceeded the preclinically predicted minimal efficacious concentration (ie, 16 ng/mL) at all dosages. Food and film coating apparently increased interpatient variability of the maximum observed plasma concentration and the area under the concentration-time curve. No objective responses were reported, and eight patients achieved stable disease (mean duration, 5.7 months). CONCLUSION: CP-868,596 potentially demonstrated greater than dose-proportional pharmacokinetics. The recommended dosage of 100 mg twice daily with food was well tolerated. Additional development as a single agent in selected populations or in combination with chemotherapy in broader populations is warranted.


Subject(s)
Antineoplastic Agents/administration & dosage , Benzimidazoles/administration & dosage , Neoplasms/drug therapy , Protein Kinase Inhibitors/administration & dosage , Receptors, Platelet-Derived Growth Factor/antagonists & inhibitors , Administration, Oral , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Benzimidazoles/adverse effects , Benzimidazoles/pharmacokinetics , Dose-Response Relationship, Drug , Female , Humans , Male , Maximum Tolerated Dose , Middle Aged , Piperidines , Protein Kinase Inhibitors/adverse effects , Protein Kinase Inhibitors/pharmacokinetics , Receptors, Platelet-Derived Growth Factor/drug effects , Young Adult
12.
J Clin Oncol ; 27(8): 1191-6, 2009 Mar 10.
Article in English | MEDLINE | ID: mdl-19188677

ABSTRACT

PURPOSE: This study was conducted to characterize the effect of food on the relative bioavailability of lapatinib. PATIENTS AND METHODS: A single 1,500-mg, oral dose of lapatinib was administered to 27 patients with advanced solid tumors on each of three occasions that were 1 week apart, in random order: after an overnight fast, with a low-fat breakfast, and with a high-fat breakfast. RESULTS: The low-fat breakfast produced mean increases in lapatinib area under the concentration-time curve (AUC) of 167% (2.67-fold) and maximum concentration (C(max)) of 142% (2.42-fold). The high-fat breakfast produced mean increases in lapatinib AUC of 325% (4.25-fold) and C(max) of 203% (3.03-fold) compared with the fasted state. Increased bioavailability in the fed state did not significantly decrease relative variability. Therefore, absolute variability in systemic exposure was increased. CONCLUSION: These large increases in lapatinib bioavailability and absolute variability support the recommendation for dosing in the fasted state to achieve consistent therapeutic exposure. Prescribers and patients should consider the potential consequences of toxicity or diminished efficacy that might result from dosing without regard to variations in diet.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Food-Drug Interactions , Neoplasms/drug therapy , Quinazolines/pharmacokinetics , Adult , Aged , Biological Availability , Cross-Over Studies , Female , Humans , Lapatinib , Male , Middle Aged , Quinazolines/adverse effects , Solubility
13.
Article in English | WHO IRIS | ID: who-170480

ABSTRACT

Dengue is endemic in the National Capital Territory (NCT) of Delhi. During the period 2003 to 2008,9737 confirmed cases of dengue fever (DF)/dengue haemorrhagic fever (DHF) and 115 deaths were recorded compared with 1341 cases and 6 deaths that happened during 1997 to 2002, representingan increase of 626%. During this period two outbreak peaks were also recorded. In addition, the satellite town of Gurgaon (Haryana) bordering Delhi also suffered a severe outbreak of DF/DHF during 2008.Aedes aegypti, the responsible vector, is fully entrenched in both urban and rural areas. DF/DHF transmission in years of extended winter rains occurs both during the summer and rainy seasons.Evaporation coolers during summer maintain low temperature and high humidity to ensure dengue transmission in some highly congested localities.


Subject(s)
Aedes , /deficiency
14.
Dig Dis Sci ; 51(8): 1426-33, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16838118

ABSTRACT

The effect of hyperbaric oxygenation (HBO2) was investigated in a rat model of indomethacin-induced enteropathy. Enteropathy was induced by two subcutaneous injections of indomethacin (7.5 mg/kg) 24 hr apart. Six groups of rats (n=8) were treated with and without HBO2 (100% oxygen at 2.3 atm absolute) for 1 hr once or twice a day for 2 or 5 days. Disease activity index (DAI) and total ulcer length were measured. Other rats were randomized into two groups (n=16) with and without HBO2 (1 hr once a day) and four rats were killed in each group at 12, 24, 48, and 72 hr after the final injection of indomethacin. Serum and intestinal mucosal TNF-alpha, IL-1beta, myeloperoxidase (MPO), and iNOS expression was measured. HBO2 treatment significantly attenuated indomethacin -induced intestinal ulceration and improved DAI. Indomethacin increased MPO activity and iNOS expression, and these were reduced by HBO2 treatment, with a concomitant reduction in TNF-alpha and IL-1beta. Our data suggest that HBO2 treatment has a beneficial effect on indomethacin-induced enteropathy and this effect is possibly mediated by decreased production of TNF-alpha and IL-1beta.


Subject(s)
Hyperbaric Oxygenation , Interleukin-1/biosynthesis , Intestinal Diseases/therapy , Tumor Necrosis Factor-alpha/biosynthesis , Ulcer/therapy , Animals , Biomarkers/blood , Disease Models, Animal , Disease Progression , Electrophoresis, Polyacrylamide Gel , Indomethacin/toxicity , Intestinal Diseases/chemically induced , Intestinal Diseases/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Male , Nitric Oxide Synthase Type II/biosynthesis , Peroxidase/metabolism , Rats , Rats, Sprague-Dawley , Severity of Illness Index , Treatment Outcome , Ulcer/chemically induced , Ulcer/metabolism
16.
Dig Dis Sci ; 50(9): 1677-83, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16133968

ABSTRACT

TNF-alpha, including other proinflammatory cytokines alone or in combination, induces iNOS expression and upregulates inflammatory responses. We evaluated the relationship between TNF-alpha and iNOS expression in indomethacin-induced jejunoileitis in male Sprague-Dawley rats. Rats were fed a daily dose of a phosphodiesterase inhibitor-either theophylline or pentoxifylline-for 2 days. Jejunoileitis was induced with two subcutaneous injections of indomethacin (7.5 mg/kg) 24 hr apart and theophylline or pentoxifylline continued for 12 hr or 4 days. Other rats received a single intraperitoneal injection of anti-TNF-alpha monoclonal antibody (TNF-Ab) 30-min before indomethacin. At 4 days TNF-Ab, theophylline, or pentoxifylline treatment significantly decreased indomethacin-induced ulceration, myeloperoxidase activity, and disease activity index. Although indomethacin significantly increased serum TNF-alpha and nitrate/nitrite levels over the control value as early as 12 hr, iNOS expression was detected only after 4 days. Serum IL-1beta level did not change at 12 hr but increased fourfold at 4 days. Treatment with TNF-Ab, theophylline, or pentoxifylline significantly reduced serum/tissue TNF-alpha, IL-1beta, nitrate/nitrite, and iNOS expression. The downregulation of nitrate/nitrite by these inhibitors suggests that TNF-alpha modulates iNOS expression.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Ileitis/chemically induced , Indomethacin/pharmacology , Indomethacin/toxicity , Jejunal Diseases/chemically induced , Nitric Oxide Synthase/biosynthesis , Tumor Necrosis Factor-alpha/physiology , Animals , Antibodies, Monoclonal , Down-Regulation , Ileitis/immunology , Ileitis/veterinary , Inflammation , Jejunal Diseases/immunology , Jejunal Diseases/veterinary , Male , Nitrates , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites , Pentoxifylline/administration & dosage , Pentoxifylline/pharmacology , Phosphodiesterase Inhibitors/administration & dosage , Phosphodiesterase Inhibitors/pharmacology , Rats , Rats, Sprague-Dawley , Theophylline/administration & dosage , Theophylline/pharmacology , Up-Regulation
17.
Plant Cell Rep ; 24(9): 556-60, 2005 Nov.
Article in English | MEDLINE | ID: mdl-15875192

ABSTRACT

Transgenic corn (MON 810), expressing the Bacillus thuringiensis (Bt) protein, Cry1Ab, was evaluated under greenhouse conditions for its tolerance to the maize stem borer, Chilo partellus. Bt corn (MON 810) provided effective protection against the stem borer even under a high level of larval infestation in the greenhouse. The observed tolerance is examined and discussed in the light of the susceptibility of C. partellus to the Cry1Ab protein in laboratory bioassays. The implications of the tissue concentrations of Cry1Ab in MON 810, and baseline susceptibility recorded in the current study, for insect-resistance management are discussed.


Subject(s)
Adaptation, Physiological , Moths/physiology , Zea mays/parasitology , Animals , Larva/physiology , Moths/growth & development
18.
Dig Dis Sci ; 46(11): 2536-41, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11713966

ABSTRACT

The role of nitric oxide (NO) synthase inhibitors in indomethacin (INDO) -induced enteropathy was investigated in male Sprague-Dawley rats. Rats were subcutaneously administered 5% sodium bicarbonate (controls), two doses of INDO 7.5 mg/kg, and three different inducible NO synthase (iNOS) inhibitors at various concentrations 24 hr, apart; aminoguanidine (AG), guanidinoethyldisulfide (GED), and n-(3-aminomethyl)benzylacetamidine (1400W). Rats were killed four days after the initial injection and small intestinal mucosa was assayed for myeloperoxidase (MPO) activity and iNOS expression by western blot analysis. Serum nitrite/nitrate (NOx) concentration was measured colorimetrically. INDO produced acute ulcers along the mesenteric border from the ileum to proximal jejunum. Rats treated with AG (25 and 50 mg/kg), GED (2.5 mg/kg), and 1400W (0.1 mg/kg) showed decreased total ulcer length and MPO activity by 51, 72, 53, and 61% and by 58, 88, 68, and 70%, respectively, compared to INDO alone. All inhibitors similarly reduced INDO-enhanced serum NOx concentrations to its basal levels. Significant iNOS expression was detected in INDO-treated rats, but the inhibitors did not alter iNOS expression. Our data suggest that NO derived from iNOS may be a key factor in the pathogenesis of acute INDO-induced enteropathy in rats.


Subject(s)
Enzyme Inhibitors/pharmacology , Indomethacin , Intestinal Diseases/chemically induced , Nitric Oxide Synthase/antagonists & inhibitors , Ulcer/chemically induced , Amidines/pharmacology , Animals , Benzylamines/pharmacology , Blotting, Western , Guanidines/pharmacology , Intestinal Diseases/prevention & control , Intestinal Mucosa/enzymology , Male , Nitric Oxide Synthase Type II , Peroxidase/metabolism , Rats , Rats, Sprague-Dawley , Ulcer/prevention & control
19.
J Lab Clin Med ; 138(4): 270-6, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11574821

ABSTRACT

We investigated the pathogenic mechanism(s) of small intestinal injury during acidosis in relation to circulating nitric oxide (NO) in an experimental rat model. Rats were anesthetized, paralyzed, and mechanically ventilated with room air. Hydrochloric acid (0.16 mmol bolus followed by 0.132 mmol/kg/h) was infused through the jugular vein for 5 hours. Control rats received a saline infusion. Arterial blood gases, blood pressure, and blood pH were measured every 30 minutes. The involvement of NO in this acidosis model was assessed by measuring plasma concentration of nitrite/nitrate (NOx) and by evaluating inducible NO synthase (iNOS) expression in small intestinal mucosa. Intestinal injury was assessed by measuring myeloperoxidase (MPO) activity, thiobarbituric acid reactants (TBARS), and histologic scores. HCl infusion was associated with hypotension, decreased blood pH, increased plasma concentration of NOx, augmented intestinal mucosal iNOS expression, MPO activity, TBARS, and histopathologic injury scores. Pretreatment with an iNOS inhibitor, aminoguanidine (AG, 50 mg/kg), reversed HCl-induced hypotension without a change in blood pH. HCl-induced lesions, MPO activity, TBARS, and plasma NOx production were decreased by AG. Our data show that the pathogenic mechanisms of acidosis-induced small intestinal lesions involve up-regulation of NO production by increased expression of iNOS and augmentation of superoxide radicals and MPO activity.


Subject(s)
Acidosis/complications , Intestinal Diseases/etiology , Intestine, Small , Nitric Oxide/physiology , Anesthesia , Animals , Blood Pressure , Carbon Dioxide/blood , Disease Models, Animal , Hemodynamics , Hydrogen-Ion Concentration , Intestinal Diseases/pathology , Intestinal Mucosa/enzymology , Intestine, Small/enzymology , Intestine, Small/pathology , Kinetics , Lipid Peroxidation , Male , Nitrates/blood , Nitric Oxide Synthase/analysis , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites/blood , Oxygen/blood , Peroxidase/analysis , Rats , Rats, Sprague-Dawley , Thiobarbituric Acid Reactive Substances/analysis
20.
Virology ; 277(1): 6-13, 2000 Nov 10.
Article in English | MEDLINE | ID: mdl-11062030

ABSTRACT

As a simian species, the langurs are not known to harbor simian retroviruses, except for one report on a simian Type D endogenous retrovirus from the spectacled langur (Trachypithecus obscurus) from Malaysia. The present report describes for the first time natural infection of the common Hanuman langur (Semnopithecus entellus) from India by a novel simian retrovirus (SRV). The new SRV is phylogenetically related to but distinct from the three molecularly characterized serotypes, SRV 1-3, of the five known serotypes of SRVs, based on sequence analyses from the 3'orf and env regions of the viral genome. The novel SRV isolated from the Indian Hanuman langur is provisionally named SRV-6.


Subject(s)
Cercopithecidae/virology , Gene Products, env/genetics , Phylogeny , Primate Diseases/virology , Retroviridae Infections/veterinary , Retroviruses, Simian/classification , Tumor Virus Infections/veterinary , Amino Acid Sequence , Animals , Evolution, Molecular , Gene Products, env/chemistry , Genes, env , India , Malaysia , Molecular Sequence Data , Retroviridae Infections/virology , Retroviruses, Simian/genetics , Retroviruses, Simian/isolation & purification , Sequence Alignment , Sequence Homology, Amino Acid , Serotyping , Tumor Virus Infections/virology
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